Humanized antibodies to the tnf-like ligand 1a (TL1a) and uses thereof

Abstract

To provide humanized anti- TL1A antibodies for the treatment of inflammatory bowel diseases (IBD), such as Crohn's (CD) and ulcerative cholitis (UC).SOLUTION: The present invention relates to antibodies or antigen binding fragments thereof that bind to the tumor necrosis factor-like ligand 1A (TL1A), wherein the antibodies or antigen binding fragments thereof comprise a heavy chain variable framework region comprising a human IGHV1 - 46 * 02 framework, or a modified human IGHV1 - 46 * 02 framework, comprising a specific sequence, and a light chain variable framework region comprising a human IGKV3 - 20 framework, or a modified human IGKV3 - 20 framework, comprising another specific sequence, wherein said heavy chain variable framework region and said light chain variable framework region may comprise from 1 to 8 amino acid modifications at particular positions.SELECTED DRAWING: Figure 3A

Description

[Technical Field]

[0001] cross reference This application claims the benefit of U.S. Provisional Patent Application No. 62 / 925,736, filed October 24, 2019, which is incorporated herein by reference in its entirety.

[0002] Sequence Listing This application contains a Sequence Listing that has been submitted electronically in ASCII format and is incorporated herein by reference in its entirety. The ASCII copy, created on October 23, 2020, is named 56884-767_601_SL.txt and is 376,991 bytes in size. [Background technology]

[0003] Inflammatory bowel disease (IBD) refers to a group of intestinal disorders that cause an inflammatory state in the digestive tract. The major types of IBD are ulcerative colitis (UC) and Crohn's disease (CD). These diseases are common, with approximately 1.86 million people diagnosed with UC and approximately 1.3 million people diagnosed with CD worldwide. Severe forms of IBD can be characterized by intestinal fibrosis, which is the accumulation of scar tissue in the intestinal wall. The number of treatments available to IBD patients is limited, and the development of new therapies has been hampered by suboptimal results in clinical trials. Furthermore, a significant number of patients experience a lack of or reduced response to existing anti-inflammatory therapies. Patients are treated with these ineffective anti-inflammatory therapies, but the disease worsens. Currently, the only treatment for patients who do not respond to first-line therapy is surgery in the form of stricture formation (reconstruction of the intestinal tract) or resection (removal of the intestinal tract). Surgical treatment for IBD is invasive and poses postoperative risks, such as anastomotic leakage, infection, and bleeding, for approximately one-third of patients undergoing surgery.

[0004] The pathogenesis of IBD is believed to involve uncontrolled immune response, which can be triggered by certain environmental factors in genetically susceptible hosts.The heterogeneity of pathogenesis and clinical course, combined with the variable response to treatment and its related side effects, suggests that targeted therapy approach is the desired treatment strategy for treating these diseases.However, there are few targeted therapies available for IBD patients, especially for those who cannot respond to existing IBD treatments.Therefore, there is a need for new therapeutic approaches for treating IBD that specifically target IBD pathogenesis. Summary of the Invention

[0005] The present disclosure provides tumor necrosis factor ligand 1A (TL1A)-binding antibodies for the treatment of IBD, including severe forms of IBD characterized by intestinal fibrosis. In various embodiments, the antibodies described herein have characteristics useful for therapeutic use, such as low immunogenicity, and / or characteristics that facilitate antibody production, such as a high percentage of monomer fraction as measured by size exclusion chromatography and / or high expression.

[0006] In one aspect, provided herein is an antibody or antigen-binding fragment thereof that binds to TL1A, wherein the antibody or antigen-binding fragment thereof is selected from the group consisting of human IGHV1-46, * 02 framework or modified human IGHV1-46 * 02 framework, and a light chain variable framework region comprising a human IGKV3-20 framework or a modified human IGKV3-20 framework; the heavy chain variable framework region and the light chain variable framework region together comprise a human IGHV1-46 *02 framework and the human IGKV3-20 framework. In some embodiments, the amino acid modifications include (a) a modification at amino acid position 47 in the heavy chain variable region; (b) a modification at amino acid position 45 in the heavy chain variable region; (c) a modification at amino acid position 55 in the heavy chain variable region; (d) a modification at amino acid position 78 in the heavy chain variable region; (e) a modification at amino acid position 80 in the heavy chain variable region; (f) a modification at amino acid position 82 in the heavy chain variable region; (g) a modification at amino acid position 89 in the heavy chain variable region; or (h) a modification at amino acid position 91 in the heavy chain variable region, according to the Kabat numbering; or a combination of two or more modifications selected from (a)-(h). In some embodiments, (a) the amino acid modification is at position 47 in the heavy chain variable region, and the amino acid at position 47 is R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V; (b) the amino acid modification is at position 45 in the heavy chain variable region, and the amino acid at position 45 is A, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V. or V; (c) the amino acid modification is at position 55 in the heavy chain variable region, and the amino acid at position 55 is A, R, N, D, C, Q, E, G, H, I, L, K, F, P, S, T, W, Y, or V; (d) the amino acid modification is at position 78 in the heavy chain variable region, and the amino acid at position 78 is A, R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, or V. or Y; (e) the amino acid modification is at position 80 in the heavy chain variable region and the amino acid at position 80 is A, R, N, D, C, Q, E, G, H, I, L, K, F, P, S, T, W, Y, or V; (f) the amino acid modification is at position 82 in the heavy chain variable region and the amino acid at position 82 is A, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V; (g) the amino acid modification is at position 89 in the heavy chain variable region and the amino acid at position 89 is A, R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, or Y; or (h) the amino acid modification is at position 91 in the heavy chain variable region and the amino acid at position 91 is A, R, N, D, C, Q, E, G, H, I, L, K, F, P, S, T, W, or Y.or V; or a combination of two or more modifications selected from (a)-(h). In some embodiments, the amino acid modifications comprise one or more of A47R, R45K, M55I, V78A, M80I, R82T, V89A, M91L in the heavy chain variable region according to the Kabat numbering. In some embodiments, the amino acid modifications comprise (a) a modification at amino acid position 54 in the light chain variable region; and / or (b) a modification at amino acid position 55 in the light chain variable region according to the Kabat numbering. In some embodiments, (a) the amino acid modification is at position 54 of the light chain variable region, where the amino acid at position 54 is A, R, N, D, C, Q, E, G, H, I, K, M, F, P, S, T, W, Y, or V; and / or (b) the amino acid modification is at position 55 of the light chain variable region, where the amino acid at position 55 is A, R, N, D, C, Q, E, G, H, I, K, M, F, P, S, T, W, Y, or V. In some embodiments, the amino acid modification comprises L54P and / or L55W in the light chain variable region according to Kabat numbering. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR1 set forth in SEQ ID NO: 1, a heavy chain CDR2 set forth in any one of SEQ ID NOs: 2 to 5, a heavy chain CDR3 set forth in any one of SEQ ID NOs: 6 to 9, a light chain CDR1 set forth in SEQ ID NO: 10, a light chain CDR2 set forth in SEQ ID NO: 11, and a light chain CDR3 set forth in any one of SEQ ID NOs: 12 to 15. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR1 set forth in SEQ ID NO: 1, a heavy chain CDR2 set forth in SEQ ID NO: 2, a heavy chain CDR3 set forth in SEQ ID NO: 6, a light chain CDR1 set forth in SEQ ID NO: 10, a light chain CDR2 set forth in SEQ ID NO: 11, and a light chain CDR3 set forth in SEQ ID NO: 12. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain framework (FR) 1 represented by SEQ ID NO: 304, a heavy chain FR2 represented by SEQ ID NO: 305 or SEQ ID NO: 313, a heavy chain FR3 represented by any one of SEQ ID NOs: 306, 307, 314, or 315, a heavy chain FR4 represented by SEQ ID NO: 308, a light chain FR1 represented by SEQ ID NO: 309, a light chain FR2 represented by SEQ ID NO: 310,In some embodiments, the antibody or antigen-binding fragment comprises a light chain FR3 set forth in SEQ ID NO: 311, or a light chain FR4 set forth in SEQ ID NO: 312, or a combination thereof, according to the Kabat numbering: (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329 Y or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, if or 373S, (kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A,(xx) L234A, L235A, and P329G, (yy) L234F, L235E, and P331S, (zz) L234A, L235E, and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329 In some embodiments, the antibody or antigen-binding fragment comprises a human IgG1 Fc region comprising the following residues: A, (ddd) G236R and L328R, (eee) G237A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or any combination of two or more selected from (nnn)(a)-(uu). In some embodiments, the antibody or antigen-binding fragment comprises a human IgG4 Fc region. In some embodiments, the antibody or antigen-binding fragment comprises an Fc region comprising a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 320-362. In some embodiments, the antibody or antigen-binding fragment comprises at least about 80% monomer fraction as determined by size exclusion chromatography. In some embodiments, the antibody or antigen-binding fragment expresses at least about 20 μg / ml total antibody, optionally between about 20 μg / ml and 70 μg / ml total antibody.

[0007] In another aspect, provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), the antibody or antigen-binding fragment thereof comprising a heavy chain variable domain comprising an amino acid sequence at least 96% identical to SEQ ID NO: 104, and a light chain variable domain comprising an amino acid sequence at least 97% identical to SEQ ID NO: 201. In some embodiments, the heavy chain variable domain comprises an amino acid sequence at least 97% identical to SEQ ID NO: 104. In some embodiments, the heavy chain variable domain comprises an amino acid sequence at least 98% identical to SEQ ID NO: 104. In some embodiments, the heavy chain variable domain comprises an amino acid sequence at least 99% identical to SEQ ID NO: 104. In some embodiments, the heavy chain variable domain comprises SEQ ID NO: 104. In some embodiments, the light chain variable domain comprises an amino acid sequence at least 98% identical to SEQ ID NO: 201. In some embodiments, the light chain variable domain comprises an amino acid sequence at least about 99% identical to SEQ ID NO: 201. In some embodiments, the light chain variable domain comprises SEQ ID NO: 201.

[0008] In another aspect, provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), the antibody or antigen-binding fragment thereof comprising a heavy chain variable domain comprising an amino acid sequence at least about 99% identical to any one of SEQ ID NOs: 101-135, and a light chain variable domain comprising an amino acid sequence at least about 99% identical to any one of SEQ ID NOs: 201-206.

[0009] In some embodiments, the antibodies or antigen-binding fragments thereof described herein are selected from the group consisting of: (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329 Y or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, or 37 6Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G, (yy) L234F, L235E,and P331S, (zz) L234A, L235E, and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R , (eee) G237A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of two or more selected from (a)-(uu). In some embodiments, the antibodies or antigen-binding fragments thereof described herein comprise a human IgG4 Fc region. In some embodiments, the antibodies or antigen-binding fragments thereof described herein comprise an Fc region comprising a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 320-362. In some embodiments, the antibodies or antigen-binding fragments thereof described herein comprise a monomer fraction of at least about 80% as determined by size exclusion chromatography. In some embodiments, the antibodies or antigen-binding fragments thereof described herein express at least about 20 μg / ml total antibody, optionally between about 20 μg / ml and 70 μg / ml total antibody.

[0010] In another aspect, provided herein is an antibody or antigen-binding fragment thereof that binds to TL1A, the antibody or antigen-binding fragment thereof comprising: a heavy chain variable region comprising: (a) an HCDR1 comprising the amino acid sequence set forth in SEQ ID NO: 1; (b) an HCDR2 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 2-5; and (c) an HCDR3 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 6-9; and a light chain variable region comprising: (d) an LCDR1 comprising the amino acid sequence set forth in SEQ ID NO: 10; (e) an LCDR2 comprising the amino acid sequence set forth in SEQ ID NO: 11; and (f) an LCDR3 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 12-15; and a crystal-forming fragment (Fc) region comprising reduced antibody-dependent cell-mediated cytotoxicity (ADCC) function compared to human IgG1 and / or reduced complement-dependent cytotoxicity (CDC) compared to human IgG1. In some embodiments, the human IgG1 comprises SEQ ID NO: 320. In some embodiments, the ADCC function of the Fc region comprising reduced ADCC is reduced by at least about 50% compared to human IgG1. In some embodiments, the CDC function of the Fc region comprising reduced CDC is reduced by at least about 50% compared to human IgG1. In some embodiments, the Fc region is selected from the group consisting of: (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, or (k) 329G, according to the Kabat numbering system. 329Y or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A,(t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339 L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E2 33P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G, (yy) L234F, L235E, and P331S, (zz) L234A, L235E, and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (eee) G237A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of (a) to (uu). In some embodiments, the antibody or antigen-binding fragment comprises (i) a human IgG4 Fc region or (ii) a human IgG4 Fc region comprising: (a) S228P, (b) S228P and L235E, or (c) S228P, F234A, and L235A, according to the Kabat numbering.The antibody or antigen-binding fragment comprises a human IgG2 Fc region; an IgG2-IgG4 cross-subclass Fc region; an IgG2-IgG3 cross-subclass Fc region; an IgG2 comprising H268Q, V309L, A330S, P331S (IgG2m4); or an IgG2 comprising V234A, G237A, P238S, H268A, V309L, A330S, P331S (IgG2σ). In some embodiments, the Fc region comprises the amino acids 329A, 329G, 329Y, 331S, 236F, 236R, 238A, 238E, 238G, 238H, 238I, 238V, 238W, 238Y, 248A, 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q according to the Kabat numbering. , 254T, 254V, 264S, 265H, 265K, 265S, 265Y, 265A, 267G, 267H, 267I, 267K, 434I, 438G, 439E, 439H, 439Q, 440A, 440D, 440E, 440F, 440M, 440T, and 440V. In some embodiments, the antibody or antigen-binding fragment comprises a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 320-362. In some embodiments, HCDR1 comprises SEQ ID NO: 1, HCDR2 comprises any one of SEQ ID NOs: 2-5, HCDR3 comprises any one of SEQ ID NOs: 6-9, LCDR1 comprises SEQ ID NO: 10, LCDR2 comprises SEQ ID NO: 11, and LCDR3 comprises any one of SEQ ID NOs: 12-15. In some embodiments, the Fc region comprises any one of SEQ ID NOs: 401-413, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 401-413. In some embodiments, the heavy chain comprises any one of SEQ ID NOs: 501-513, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 501-513. In some embodiments, the light chain has a sequence identical to any one of SEQ ID NOs: 514, or ...In some embodiments, the antibody or antigen-binding fragment comprises a sequence at least about 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 2, SEQ ID NO: 6, and SEQ ID NO: 12. In some embodiments, the antibody or antigen-binding fragment comprises any one of SEQ ID NOs: 401-413, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 401-413. In some embodiments, the antibody or antigen-binding fragment comprises at least about 80% monomer fraction as determined by size exclusion chromatography. In some embodiments, the antibody or antigen-binding fragment expresses at least about 20 μg / ml total antibody, optionally between about 20 μg / ml and 70 μg / ml total antibody.

[0011] Also provided are methods of treating fibrosis or an intestinal inflammatory condition, disease, or disorder in a subject in need thereof, comprising administering to the subject an antibody or antigen-binding fragment of any of the antibodies or antigen-binding fragments disclosed herein. In some embodiments, the subject suffers from fibrosis. In some embodiments, the subject suffers from an intestinal inflammatory condition, disease, or disorder. In some embodiments, the intestinal inflammatory condition, disease, or disorder comprises inflammatory bowel disease (IBD). In some embodiments, the IBD comprises Crohn's disease. In some embodiments, the IBD comprises ulcerative colitis.

[0012] In some embodiments, the antibody or antigen-binding fragment described herein is present in the liquid composition at a concentration of 10 mg / ml to 170 mg / ml of antibody or antigen-binding fragment. In some embodiments, the antibody or antigen-binding fragment is at a concentration of 10 mg / ml to 170 mg / ml. In some embodiments, the viscosity is about 4 to about 30 mPa-s (milliPascal seconds (mPa·s)). In some embodiments, the viscosity is about 4 to about 10 mPa-s (milliPascal seconds (mPa·s)).

[0013] In another aspect, provided herein is an antibody or antigen-binding fragment thereof that binds to TL1A, wherein the antibody or antigen-binding fragment thereof is selected from the group consisting of human IGHV1-46, * 02 framework or modified human IGHV1-46 * a heavy chain variable framework region comprising a human IGKV3-20 framework or a modified human IGKV3-20 framework, and a light chain variable framework region comprising a human IGKV3-20 framework or a modified human IGKV3-20 framework; the heavy chain variable framework region and the light chain variable framework region together comprise a human IGHV1-46 * In some embodiments, the heavy chain variable framework region and the light chain variable framework region are collectively represented by the human IGHV1-46 framework. *The IGKV3-20 framework may comprise 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, or no amino acid modifications from the IGKV3-20 framework and the human IGKV3-20 framework. In some embodiments, the amino acid modification comprises a modification at amino acid position 1 in the heavy chain variable region according to the Kabat numbering. In some embodiments, the amino acid at position 1 comprises A, R, N, D, C, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V. In some embodiments, the amino acid at position 1 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 1 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amidic amino acid. In some embodiments, the amino acid at position 1 comprises an E. In some embodiments, the amino acid modification comprises a modification at amino acid position 45 in the heavy chain variable region according to the Kabat numbering. In some embodiments, the amino acid at position 45 comprises A, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V. In some embodiments, the amino acid at position 45 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 45 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 45 comprises a K. In some embodiments, the amino acid modification comprises a modification at amino acid position 47 in the heavy chain variable region according to the Kabat numbering system. In some embodiments, the amino acid at position 47 comprises R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V. In some embodiments, the amino acid at position 47 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 47 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 47 comprises an R. In some embodiments, the amino acid modification comprises a modification at amino acid position 55 in the heavy chain variable region according to the Kabat numbering.In some embodiments, the amino acid at position 55 comprises A, R, N, D, C, Q, E, G, H, I, L, K, F, P, S, T, W, Y, or V. In some embodiments, the amino acid at position 55 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 55 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 55 comprises I. In some embodiments, the amino acid modification comprises a modification at amino acid position 78 in the heavy chain variable region according to the Kabat numbering. In some embodiments, the amino acid at position 78 comprises A, R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, or Y. In some embodiments, the amino acid at position 78 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 78 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 78 comprises an A. In some embodiments, the amino acid modification comprises a modification at amino acid position 80 in the heavy chain variable region according to the Kabat numbering. In some embodiments, the amino acid at position 80 comprises A, R, N, D, C, Q, E, G, H, I, L, K, F, P, S, T, W, Y, or V. In some embodiments, the amino acid at position 80 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 80 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 80 comprises an I. In some embodiments, the amino acid modification comprises a modification at amino acid position 82 in the heavy chain variable region according to the Kabat numbering. In some embodiments, the amino acid at position 82 comprises A, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V. In some embodiments, the amino acid at position 82 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid.In some embodiments, the amino acid at position 82 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 82 comprises a T. In some embodiments, the amino acid modification comprises a modification at amino acid position 89 in the heavy chain variable region according to the Kabat numbering. In some embodiments, the amino acid at position 89 comprises A, R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, or Y. In some embodiments, the amino acid at position 89 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 89 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 89 comprises an A. In some embodiments, the amino acid modification comprises a modification at amino acid position 91 in the heavy chain variable region according to the Kabat numbering. In some embodiments, the amino acid at position 91 comprises A, R, N, D, C, Q, E, G, H, I, L, K, F, P, S, T, W, Y, or V. In some embodiments, the amino acid at position 91 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 91 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 91 comprises L.

[0014] In some embodiments, the amino acid modification comprises one or more of Q1E, R45K, A47R, M55I, V78A, M80I, R82T, V89A, M91L in the heavy chain variable region according to Kabat numbering. In some embodiments, the amino acid modification comprises Q1E. In some embodiments, the amino acid modification comprises R45K. In some embodiments, the amino acid modification comprises A47R. In some embodiments, the amino acid modification comprises M55I. In some embodiments, the amino acid modification comprises V78A. In some embodiments, the amino acid modification comprises M80I. In some embodiments, the amino acid modification comprises R82T. In some embodiments, the amino acid modification comprises V89A. In some embodiments, the amino acid modification comprises M91L.

[0015] In some embodiments, the amino acid modification comprises a modification at amino acid position 54 in the light chain variable region according to the Kabat numbering. In some embodiments, the amino acid at position 54 comprises A, R, N, D, C, Q, E, G, H, I, K, M, F, P, S, T, W, Y, or V. In some embodiments, the amino acid at position 54 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 54 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 54 comprises a P. In some embodiments, the amino acid modification comprises a modification at amino acid position 55 in the light chain variable region according to the Kabat numbering. In some embodiments, the amino acid at position 55 comprises A, R, N, D, C, Q, E, G, H, I, K, M, F, P, S, T, W, Y, or V. In some embodiments, the amino acid at position 55 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, the amino acid at position 55 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, the amino acid at position 55 comprises a W.

[0016] In some embodiments, the amino acid modification comprises L54P and / or L55W in the light chain variable region according to Kabat numbering. In some embodiments, the amino acid modification comprises L54P. In some embodiments, the amino acid modification comprises L55W.

[0017] In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR1 set forth in SEQ ID NO: 1. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR2 set forth in SEQ ID NO: 2. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR2 set forth in SEQ ID NO: 3. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR2 set forth in SEQ ID NO: 4. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR2 set forth in SEQ ID NO: 5. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR3 set forth in SEQ ID NO: 6. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR3 set forth in SEQ ID NO: 7. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR3 set forth in SEQ ID NO: 8. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain CDR3 set forth in SEQ ID NO: 9. In some embodiments, the antibody or antigen-binding fragment comprises a light chain CDR1 set forth in SEQ ID NO: 10. In some embodiments, the antibody or antigen-binding fragment comprises a light chain CDR2 set forth in SEQ ID NO: 11. In some embodiments, the antibody or antigen-binding fragment comprises a light chain CDR3 set forth in SEQ ID NO: 12. In some embodiments, the antibody or antigen-binding fragment comprises a light chain CDR3 set forth in SEQ ID NO: 13. In some embodiments, the antibody or antigen-binding fragment comprises a light chain CDR3 set forth in SEQ ID NO: 14. In some embodiments, the antibody or antigen-binding fragment comprises a light chain CDR3 set forth in SEQ ID NO: 15.

[0018] In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain FR1 set forth in SEQ ID NO: 304. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain FR2 set forth in SEQ ID NO: 305. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain FR2 set forth in SEQ ID NO: 313. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain FR3 set forth in SEQ ID NO: 306. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain FR3 set forth in SEQ ID NO: 307. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain FR3 set forth in SEQ ID NO: 314. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain FR3 set forth in SEQ ID NO: 315. In some embodiments, the antibody or antigen-binding fragment comprises a heavy chain FR4 set forth in SEQ ID NO: 308. In some embodiments, the antibody or antigen-binding fragment comprises a light chain FR1 set forth in SEQ ID NO: 309. In some embodiments, the antibody or antigen-binding fragment comprises a light chain FR2 set forth in SEQ ID NO: 310. In some embodiments, the antibody or antigen-binding fragment comprises a light chain FR3 set forth in SEQ ID NO: 311. In some embodiments, the antibody or antigen-binding fragment comprises a light chain FR4 set forth in SEQ ID NO: 312.

[0019] In another aspect, provided herein is an antibody or antigen-binding fragment thereof that binds to TL1A, comprising: (a) a heavy chain variable region comprising SEQ ID NO: 301 (X1VQLVQSGAEVKKPGASVKVSCKAS[HCDR1]WVX2QX3PGQGLEWX4G[HCDR2]RX5TX6TX7DTSTSTX8YX9ELSSLRSEDTAVYYCAR[HCDR3]WGQGTTVTVSS); and (b) a heavy chain variable region comprising SEQ ID NO: 303 (EI VLTQSPGTLSLSPGERATLSC[LCDR1]WYQQKPGQAPRX10X11IY[LCDR2]GIPDRFSGSGSGTDFTLTISRLEPEDFAVYYC[LCDR3]FGGGTKLEIK), and each of X1 to X11 is independently selected from A, R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V.

[0020] In some embodiments, X1 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X1 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X2 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X2 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X3 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X3 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X4 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X4 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X5 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X5 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X6 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X6 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X7 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X7 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X8 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X8 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid.In some embodiments, X9 comprises a hydrophobic, hydrophilic, or amphipathic amino acid. In some embodiments, X9 comprises an aliphatic, aromatic, acidic, basic, hydroxyl, sulfur-containing, or amide amino acid. In some embodiments, X10 comprises a hydrophobic, hydrophilic, or amphipathic amino acid. In some embodiments, X10 comprises an aliphatic, aromatic, acidic, basic, hydroxyl, sulfur-containing, or amide amino acid. In some embodiments, X11 comprises a hydrophobic, hydrophilic, or amphipathic amino acid. In some embodiments, X11 comprises an aliphatic, aromatic, acidic, basic, hydroxyl, sulfur-containing, or amide amino acid.

[0021] In some embodiments, X1 = Q or E, X2 = R or K, X3 = A or R, X4 = M or I, X5 = V or A, X6 = M or I, X7 = R or T, X8 = V or A, X9 = M or L, X10 = L or P, and X11 = L or W. In some embodiments, X1 = Q. In some embodiments, X1 = E. In some embodiments, X2 = R. In some embodiments, X2 = K. In some embodiments, X3 = A. In some embodiments, X3 = R. In some embodiments, X4 = M. In some embodiments, X4 = I. In some embodiments, X5 = V. In some embodiments, X5 = A. In some embodiments, X6 = M. In some embodiments, X6 = I. In some embodiments, X7 = R. In some embodiments, X7 = T. In some embodiments, X8 = V. In some embodiments, X8 = A. In some embodiments, X9 = M. In some embodiments, X9 = L. In some embodiments, X10 = L. In some embodiments, X10 = P. In some embodiments, X11 = L. In some embodiments, X11 = W.

[0022] In some embodiments, HCDR1 comprises SEQ ID NO: 1. In some embodiments, HCDR2 comprises SEQ ID NO: 2. In some embodiments, HCDR2 comprises SEQ ID NO: 3. In some embodiments, HCDR2 comprises SEQ ID NO: 4. In some embodiments, HCDR2 comprises SEQ ID NO: 5. In some embodiments, HCDR3 comprises SEQ ID NO: 6. In some embodiments, HCDR3 comprises SEQ ID NO: 7. In some embodiments, HCDR3 comprises SEQ ID NO: 8. In some embodiments, HCDR3 comprises SEQ ID NO: 9. In some embodiments, LCDR1 comprises SEQ ID NO: 10. In some embodiments, LCDR2 comprises SEQ ID NO: 11. In some embodiments, LCDR3 comprises SEQ ID NO: 12. In some embodiments, LCDR3 comprises SEQ ID NO: 13. In some embodiments, LCDR3 comprises SEQ ID NO: 14. In some embodiments, the antibody or antigen-binding fragment comprises a light chain CDR3 set forth in SEQ ID NO: 15.

[0023] In another aspect, provided herein is an antibody or antigen-binding fragment thereof that binds to TL1A, comprising: (a) a heavy chain variable region comprising SEQ ID NO: 302 (X1VQLVQSGAEVKKPGASVKVSCKAS[HCDR1]WVX2QX3PGQGLEWX4G[HCDR2]RX5TX6TX7DTSTSTX8YX9ELSSLRSEDTAVYYC[HCDR3]WGQGTTVTVSS); and (b) a heavy chain variable region comprising SEQ ID NO: 303 (EIV LTQSPGTLSLSPGERATLSC[LCDR1]WYQQKPGQAPRX10X11IY[LCDR2]GIPDRFSGSGSGTDFTLTISRLEPEDFAVYYC[LCDR3]FGGGTKLEIK), and each of X1 to X11 is independently selected from A, R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V.

[0024] In some embodiments, X1 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X1 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X2 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X2 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X3 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X3 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X4 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X4 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X5 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X5 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X6 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X6 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X7 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X7 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid. In some embodiments, X8 comprises a hydrophobic amino acid, a hydrophilic amino acid, or an amphipathic amino acid. In some embodiments, X8 comprises an aliphatic amino acid, an aromatic amino acid, an acidic amino acid, a basic amino acid, a hydroxyl amino acid, a sulfur-containing amino acid, or an amide amino acid.In some embodiments, X9 comprises a hydrophobic, hydrophilic, or amphipathic amino acid. In some embodiments, X9 comprises an aliphatic, aromatic, acidic, basic, hydroxyl, sulfur-containing, or amide amino acid. In some embodiments, X10 comprises a hydrophobic, hydrophilic, or amphipathic amino acid. In some embodiments, X10 comprises an aliphatic, aromatic, acidic, basic, hydroxyl, sulfur-containing, or amide amino acid. In some embodiments, X11 comprises a hydrophobic, hydrophilic, or amphipathic amino acid. In some embodiments, X11 comprises an aliphatic, aromatic, acidic, basic, hydroxyl, sulfur-containing, or amide amino acid.

[0025] In some embodiments, X1 = Q or E, X2 = R or K, X3 = A or R, X4 = M or I, X5 = V or A, X6 = M or I, X7 = R or T, X8 = V or A, X9 = M or L, X10 = L or P, and X11 = L or W. In some embodiments, X1 = Q. In some embodiments, X1 = E. In some embodiments, X2 = R. In some embodiments, X2 = K. In some embodiments, X3 = A. In some embodiments, X3 = R. In some embodiments, X4 = M. In some embodiments, X4 = I. In some embodiments, X5 = V. In some embodiments, X5 = A. In some embodiments, X6 = M. In some embodiments, X6 = I. In some embodiments, X7 = R. In some embodiments, X7 = T. In some embodiments, X8 = V. In some embodiments, X8 = A. In some embodiments, X9 = M. In some embodiments, X9 = L. In some embodiments, X10 = L. In some embodiments, X10 = P. In some embodiments, X11 = L. In some embodiments, X11 = W.

[0026] In some embodiments, HCDR1 comprises SEQ ID NO: 1. In some embodiments, HCDR2 comprises SEQ ID NO: 2. In some embodiments, HCDR2 comprises SEQ ID NO: 3. In some embodiments, HCDR2 comprises SEQ ID NO: 4. In some embodiments, HCDR2 comprises SEQ ID NO: 5. In some embodiments, HCDR3 comprises SEQ ID NO: 6. In some embodiments, HCDR3 comprises SEQ ID NO: 7. In some embodiments, HCDR3 comprises SEQ ID NO: 8. In some embodiments, HCDR3 comprises SEQ ID NO: 9. In some embodiments, LCDR1 comprises SEQ ID NO: 10. In some embodiments, LCDR2 comprises SEQ ID NO: 11. In some embodiments, LCDR3 comprises SEQ ID NO: 12. In some embodiments, LCDR3 comprises SEQ ID NO: 13. In some embodiments, LCDR3 comprises SEQ ID NO: 14. In some embodiments, LCDR3 comprises SEQ ID NO: 15.

[0027] In some embodiments, the heavy chain variable region comprises SEQ ID NO: 101. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 102. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 103. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 104. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 105. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 106. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 107. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 108. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 109. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 110. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 111. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 112. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 113. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 114. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 115. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 116. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 117. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 118. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 119. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 120. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 121. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 122. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 123. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 124. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 125. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 126. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 127. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 128. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 129. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 130. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 131. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 132. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 133. In some embodiments, the heavy chain variable region comprises SEQ ID NO: 134. In some embodiments, the heavy chain variable region comprises SEQ ID NO:135.In some embodiments, the light chain variable region comprises SEQ ID NO: 201. In some embodiments, the light chain variable region comprises SEQ ID NO: 202. In some embodiments, the light chain variable region comprises SEQ ID NO: 203. In some embodiments, the light chain variable region comprises SEQ ID NO: 204. In some embodiments, the light chain variable region comprises SEQ ID NO: 205. In some embodiments, the light chain variable region comprises SEQ ID NO: 206.

[0028] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), the antibody or antigen-binding fragment thereof comprising a heavy chain variable domain comprising an amino acid sequence at least about 96% identical to SEQ ID NO: 104, and a light chain variable domain comprising an amino acid sequence at least about 97% identical to SEQ ID NO: 201. In some embodiments, the heavy chain variable domain comprises an amino acid sequence at least about 97% identical to SEQ ID NO: 104. In some embodiments, the heavy chain variable domain comprises an amino acid sequence at least about 98% identical to SEQ ID NO: 104. In some embodiments, the heavy chain variable domain comprises an amino acid sequence at least about 99% identical to SEQ ID NO: 104. In some embodiments, the heavy chain variable domain comprises SEQ ID NO: 104. In some embodiments, the light chain variable domain comprises an amino acid sequence at least about 98% identical to SEQ ID NO: 201. In some embodiments, the light chain variable domain comprises an amino acid sequence at least about 99% identical to SEQ ID NO: 201. In some embodiments, the light chain variable domain comprises SEQ ID NO: 201.

[0029] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), the antibody or antigen-binding fragment thereof comprising a heavy chain variable domain comprising an amino acid sequence at least about 99% identical to SEQ ID NO: 107, and a light chain variable domain comprising an amino acid sequence at least about 97% identical to SEQ ID NO: 201. In some embodiments, the heavy chain variable domain comprises SEQ ID NO: 107. In some embodiments, the light chain variable domain comprises an amino acid sequence at least about 98% identical to SEQ ID NO: 201. In some embodiments, the light chain variable domain comprises an amino acid sequence at least about 99% identical to SEQ ID NO: 201. In some embodiments, the light chain variable domain comprises SEQ ID NO: 201.

[0030] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising an amino acid sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 101-135, and a light chain variable domain comprising an amino acid sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 201-206. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 101. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 102. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 103. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 104. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 105. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 106. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 107. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 108. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 109. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 110.In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 111. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 112. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 113. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 114. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 115. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 116. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 117. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 118. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 119. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 120. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 121. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 122. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 123. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 124.In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 125. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 126. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 127. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 128. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 129. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 130. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 131. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 132. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 133. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 134. In some embodiments, the heavy chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 135. In some embodiments, the light chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. In some embodiments, the light chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 202. In some embodiments, the light chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 203.In some embodiments, the light chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204. In some embodiments, the light chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. In some embodiments, the light chain variable domain comprises a sequence at least about 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 206.

[0031] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 101 and a light chain variable domain comprising SEQ ID NO: 201.

[0032] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 102 and a light chain variable domain comprising SEQ ID NO: 201.

[0033] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 103 and a light chain variable domain comprising SEQ ID NO: 202.

[0034] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 104 and a light chain variable domain comprising SEQ ID NO: 201.

[0035] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 105 and a light chain variable domain comprising SEQ ID NO: 201.

[0036] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 103 and a light chain variable domain comprising SEQ ID NO: 201.

[0037] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 106 and a light chain variable domain comprising SEQ ID NO: 201.

[0038] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 107 and a light chain variable domain comprising SEQ ID NO: 201.

[0039] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 108 and a light chain variable domain comprising SEQ ID NO: 202.

[0040] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 109 and a light chain variable domain comprising SEQ ID NO: 202.

[0041] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 108 and a light chain variable domain comprising SEQ ID NO: 201.

[0042] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 109 and a light chain variable domain comprising SEQ ID NO: 201.

[0043] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 108 and a light chain variable domain comprising SEQ ID NO: 203.

[0044] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 108 and a light chain variable domain comprising SEQ ID NO: 204.

[0045] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 107 and a light chain variable domain comprising SEQ ID NO: 204.

[0046] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 107 and a light chain variable domain comprising SEQ ID NO: 202.

[0047] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 110 and a light chain variable domain comprising SEQ ID NO: 204.

[0048] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 111 and a light chain variable domain comprising SEQ ID NO: 201.

[0049] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 112 and a light chain variable domain comprising SEQ ID NO: 201.

[0050] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 113 and a light chain variable domain comprising SEQ ID NO: 204.

[0051] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 114 and a light chain variable domain comprising SEQ ID NO: 201.

[0052] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 115 and a light chain variable domain comprising SEQ ID NO: 202.

[0053] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 116 and a light chain variable domain comprising SEQ ID NO: 201.

[0054] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 117 and a light chain variable domain comprising SEQ ID NO: 201.

[0055] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 118 and a light chain variable domain comprising SEQ ID NO: 204.

[0056] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 114 and a light chain variable domain comprising SEQ ID NO: 204.

[0057] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 102 and a light chain variable domain comprising SEQ ID NO: 204.

[0058] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 104 and a light chain variable domain comprising SEQ ID NO: 204.

[0059] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 119 and a light chain variable domain comprising SEQ ID NO: 204.

[0060] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 119 and a light chain variable domain comprising SEQ ID NO: 201.

[0061] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 101 and a light chain variable domain comprising SEQ ID NO: 204.

[0062] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 105 and a light chain variable domain comprising SEQ ID NO: 204.

[0063] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 120 and a light chain variable domain comprising SEQ ID NO: 204.

[0064] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 121 and a light chain variable domain comprising SEQ ID NO: 202.

[0065] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 122 and a light chain variable domain comprising SEQ ID NO: 202.

[0066] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 122 and a light chain variable domain comprising SEQ ID NO: 204.

[0067] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 123 and a light chain variable domain comprising SEQ ID NO: 202.

[0068] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 124 and a light chain variable domain comprising SEQ ID NO: 202.

[0069] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 125 and a light chain variable domain comprising SEQ ID NO: 205.

[0070] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 116 and a light chain variable domain comprising SEQ ID NO: 205.

[0071] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 117 and a light chain variable domain comprising SEQ ID NO: 205.

[0072] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 126 and a light chain variable domain comprising SEQ ID NO: 205.

[0073] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 127 and a light chain variable domain comprising SEQ ID NO: 205.

[0074] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 127 and a light chain variable domain comprising SEQ ID NO: 201.

[0075] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 121 and a light chain variable domain comprising SEQ ID NO: 201.

[0076] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 122 and a light chain variable domain comprising SEQ ID NO: 205.

[0077] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 122 and a light chain variable domain comprising SEQ ID NO: 201.

[0078] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 122 and a light chain variable domain comprising SEQ ID NO: 206.

[0079] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 124 and a light chain variable domain comprising SEQ ID NO: 205.

[0080] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 124 and a light chain variable domain comprising SEQ ID NO: 201.

[0081] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 128 and a light chain variable domain comprising SEQ ID NO: 205.

[0082] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 128 and a light chain variable domain comprising SEQ ID NO: 206.

[0083] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 129 and a light chain variable domain comprising SEQ ID NO: 205.

[0084] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 130 and a light chain variable domain comprising SEQ ID NO: 205.

[0085] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 131 and a light chain variable domain comprising SEQ ID NO: 205.

[0086] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 132 and a light chain variable domain comprising SEQ ID NO: 205.

[0087] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 133 and a light chain variable domain comprising SEQ ID NO: 205.

[0088] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 134 and a light chain variable domain comprising SEQ ID NO: 205.

[0089] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 135 and a light chain variable domain comprising SEQ ID NO: 205.

[0090] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 132 and a light chain variable domain comprising SEQ ID NO: 201.

[0091] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 126 and a light chain variable domain comprising SEQ ID NO: 201.

[0092] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain variable domain comprising SEQ ID NO: 130 and a light chain variable domain comprising SEQ ID NO: 201.

[0093] Further provided herein is an antibody or antigen-binding fragment thereof that binds to tumor necrosis factor-like protein 1A (TL1A), comprising a heavy chain domain comprising any one of SEQ ID NOs: 501 to 513, and a light chain domain comprising SEQ ID NO: 514.

[0094] In another aspect, provided herein is an antibody or antigen-binding fragment thereof that binds to TL1A, the antibody or antigen-binding fragment thereof comprising: a heavy chain variable region comprising: (a) an HCDR1 comprising the amino acid sequence set forth in SEQ ID NO: 1; (b) an HCDR2 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 2-5; and (c) an HCDR3 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 6-9; and a light chain variable region comprising: (d) an LCDR1 comprising the amino acid sequence set forth in SEQ ID NO: 10; (e) an LCDR2 comprising the amino acid sequence set forth in SEQ ID NO: 11; and (f) an LCDR3 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 12-15; and a crystal-forming fragment (Fc) region comprising reduced antibody-dependent cell-mediated cytotoxicity (ADCC) function compared to human IgG1 and / or reduced complement-dependent cytotoxicity (CDC) compared to human IgG1. In some embodiments, the human IgG1 comprises SEQ ID NO: 320. In some embodiments, the ADCC function of the Fc region comprising reduced ADCC is reduced by at least about 50% compared to human IgG1. In some embodiments, the CDC function of the Fc region, including reduced ADCC, is reduced by at least about 50% compared to human IgG1. In some embodiments, the Fc region is selected from the group consisting of: (a) 297A, 297Q, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, according to the Kabat numbering system. (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H,267I or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343 I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (u u) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G, (yy) L234F, L235E, and P331S, (zz) L234A, L235E, and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (Ig G1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (eee) G237A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of (a) to (uu). In some embodiments, the antibody or antigen-binding fragment comprises (i) a human IgG4 Fc region or (ii) a human IgG4 Fc region comprising (a) S228P and L235E, or (b) S228P, F234A, and L235A, according to the Kabat numbering.In some embodiments, the antibody or antigen-binding fragment comprises a human Fc region comprising high mannose glycosylation. In some embodiments, the Fc region comprises a human IgG1 with substitutions selected from 297A, 297Q, 297D, 279F, 279K, 279L, 228P, 235A, 235E, 235G, 235Q, 235R, 235S, 237A, 237E, 237K, 237N, 237R, 268K, 269N, 269Q, 270A, 270G, 270M, 270N, 424H, 424M, and 424V according to Kabat numbering. In some embodiments, the Fc region comprises a human IgG1 with substitutions selected from 271T, 272N, 292E, 292F, 292G, 292I, 293S, 301W, 304E, 311E, 311G, 311S, 255N, 256H, 256K, 256R, 256V, 316F, 328V, 330R, 339E, 339L, 343I, 343V, 373A, 373G, 373S, 376E, 376W, 376Y, 380D, 382D, 382P, 385P, 234A, 234V, 234F, 233P, 328A, 327Q, and 327T according to Kabat numbering. In some embodiments, the Fc region comprises the amino acids 329A, 329G, 329Y, 331S, 236F, 236R, 238A, 238E, 238G, 238H, 238I, 238V, 238W, 238Y, 248A, 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q according to the Kabat numbering. , 254T, 254V, 264S, 265H, 265K, 265S, 265Y, 265A, 267G, 267H, 267I, 267K, 434I, 438G, 439E, 439H, 439Q, 440A, 440D, 440E, 440F, 440M, 440T, and 440V.The HCDR1 comprises a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 320-362. In some embodiments, HCDR1 comprises SEQ ID NO: 1. In some embodiments, HCDR2 comprises SEQ ID NO: 2. In some embodiments, HCDR2 comprises SEQ ID NO: 3. In some embodiments, HCDR2 comprises SEQ ID NO: 4. In some embodiments, HCDR2 comprises SEQ ID NO: 5. In some embodiments, HCDR3 comprises SEQ ID NO: 6. In some embodiments, HCDR3 comprises SEQ ID NO: 7. In some embodiments, HCDR3 comprises SEQ ID NO: 8. In some embodiments, HCDR3 comprises SEQ ID NO: 9. In some embodiments, LCDR1 comprises SEQ ID NO: 10. In some embodiments, LCDR2 comprises SEQ ID NO: 11. In some embodiments, LCDR3 comprises SEQ ID NO: 12. In some embodiments, LCDR3 comprises SEQ ID NO: 13. In some embodiments, LCDR3 comprises SEQ ID NO: 14. In some embodiments, LCDR3 comprises SEQ ID NO: 15.

[0095] In another aspect, provided herein is an antibody or antigen-binding fragment thereof that binds to TL1A, comprising a heavy chain variable region comprising: (a) an HCDR1 comprising the amino acid sequence set forth in SEQ ID NO: 1; (b) an HCDR2 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 2 to 5; and (c) an HCDR3 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 6 to 9; and a light chain variable region comprising: (d) an LCDR1 comprising the amino acid sequence set forth in SEQ ID NO: 10; (e) an LCDR2 comprising the amino acid sequence set forth in SEQ ID NO: 11; and (f) an LCDR3 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 12 to 15. In some embodiments, the heavy chain variable region is selected from the group consisting of human IGHV1-46, ... * 02 framework or modified human IGHV1-46 *02 framework. In some embodiments, the light chain variable framework region comprises a human IGKV3-20 framework or a modified human IGKV3-20 framework. In some embodiments, the heavy chain variable region comprises one or more of the following amino acids according to Kabat numbering: 1E, 45K, 47R, 55I, 78A, 80I, 82T, 89A, 91L. In some embodiments, the heavy chain variable region comprises 1E. In some embodiments, the heavy chain variable region comprises 45K. In some embodiments, the heavy chain variable region comprises 47R. In some embodiments, the heavy chain variable region comprises 55I. In some embodiments, the heavy chain variable region comprises 78A. In some embodiments, the heavy chain variable region comprises 80I. In some embodiments, the heavy chain variable region comprises 82T. In some embodiments, the heavy chain variable region comprises 89A. In some embodiments, the heavy chain variable region comprises 91L. In some embodiments, the light chain variable region comprises one or more of the following amino acids, according to Kabat numbering: 54P and 55W. In some embodiments, the light chain variable region comprises 54P. In some embodiments, the light chain variable region comprises 55W. In some embodiments, HCDR2 comprises SEQ ID NO:2. In some embodiments, HCDR2 comprises SEQ ID NO:3. In some embodiments, HCDR2 comprises SEQ ID NO:4. In some embodiments, HCDR2 comprises SEQ ID NO:5. In some embodiments, HCDR3 comprises SEQ ID NO:6. In some embodiments, HCDR3 comprises SEQ ID NO:7. In some embodiments, HCDR3 comprises SEQ ID NO:8. In some embodiments, HCDR3 comprises SEQ ID NO:9. In some embodiments, LCDR3 comprises SEQ ID NO:12. In some embodiments, LCDR3 comprises SEQ ID NO:13. In some embodiments, LCDR3 comprises SEQ ID NO:14. In some embodiments, LCDR3 comprises SEQ ID NO:15.

[0096] In some embodiments, the antibodies or antigen-binding fragments described herein are selected from the group consisting of: (a) 297A, 297Q, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, (k) 331 S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or (w) 270A, 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 38 2D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G, (yy) L234F, L235E, and P331S, (zz) L234A,L235E, and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (ee (e) G237A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of (a)-(uu). In some embodiments, the antibody or antigen-binding fragment herein comprises (i) a human IgG4 Fc region or (ii) a human IgG4 Fc region comprising: (a) S228P and L235E, or (b) S228P, F234A, and L235A, according to Kabat numbering. In some embodiments, the antibodies or antigen-binding fragments herein comprise a human IgG2 Fc region; an IgG2-IgG4 cross-subclass Fc region; an IgG2-IgG3 cross-subclass Fc region; an IgG2 comprising H268Q, V309L, A330S, P331S (IgG2m4); or an IgG2 comprising V234A, G237A, P238S, H268A, V309L, A330S, P331S (IgG2σ). In some embodiments, the antibodies or antigen-binding fragments herein comprise a human Fc region comprising high mannose glycosylation. In some embodiments, any of the antibodies or antigen-binding fragments described herein comprise a human IgG4 Fc region.

[0097] In some embodiments, the antibody or antigen-binding fragment described herein comprises a human IgG1 with a substitution selected from 297A, 297Q, 297D, 279F, 279K, 279L, 228P, 235A, 235E, 235G, 235Q, 235R, 235S, 237A, 237E, 237K, 237N, 237R, 268K, 269N, 269Q, 270A, 270G, 270M, 270N, 424H, 424M, and 424V according to the Kabat numbering. In some embodiments, the antibody or antigen-binding fragment described herein comprises a human IgG1 with a substitution selected from 271T, 272N, 292E, 292F, 292G, 292I, 293S, 301W, 304E, 311E, 311G, 311S, 255N, 256H, 256K, 256R, 256V, 316F, 328V, 330R, 339E, 339L, 343I, 343V, 373A, 373G, 373S, 376E, 376W, 376Y, 380D, 382D, 382P, 385P, 234A, 234V, 234F, 233P, 328A, 327Q, and 327T according to Kabat numbering. In some embodiments, the antibodies or antigen-binding fragments described herein are selected from the group consisting of: 329A, 329G, 329Y, 331S, 236F, 236R, 238A, 238E, 238G, 238H, 238I, 238V, 238W, 238Y, 248A, 254D, 254E, 254G, 254H, 254I, 254N, 254D, 254E, 254G, 254H, 254I, 254N, 254D, 254E, 254G, 254H, 254I, 254N, 254D, 254E, 254G, 254H, 254I, 254N, 254D, 254E, 254F ... and a human IgG1 having a substitution selected from 254P, 254Q, 254T, 254V, 264S, 265H, 265K, 265S, 265Y, 265A, 267G, 267H, 267I, 267K, 434I, 438G, 439E, 439H, 439Q, 440A, 440D, 440E, 440F, 440M, 440T, and 440V.

[0098] In some embodiments, the antibodies or antigen-binding fragments described herein comprise an Fc region comprising a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 320-362.

[0099] In some embodiments, the antibodies or antigen-binding fragments described herein comprise at least about 80% monomer fraction as determined by size exclusion chromatography. In some embodiments, the antibodies or antigen-binding fragments described herein comprise at least about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% monomer fraction. In some embodiments, the size exclusion chromatography comprises injecting the purified antibody or antigen-binding fragment into a size exclusion column, and the antibody or antigen-binding fragment is purified with Protein A. In some embodiments, the antibody or antigen-binding fragment is purified as described in Example 2. In some embodiments, the antibody or antigen-binding fragment is expressed under the conditions described in Example 2. In some embodiments, the size exclusion chromatography column has an inner diameter of 4.6 mm. In some embodiments, the size exclusion chromatography column has a total length of 150 mm. In some embodiments, the size exclusion chromatography column has a pore size of 200 Å. In some embodiments, the size exclusion chromatography column has a particle size of 1.7 micrometers. In some embodiments, the size exclusion chromatography column is an ACQUITY UPLC BEH200 SEC column. In some embodiments, the antibody or antigen-binding fragment is injected in a total volume of 15 μL. In some embodiments, the antibody or antigen-binding fragment is injected at a concentration of about 0.1 μg / μL to about 1.0 μg / μL. In some embodiments, the size exclusion chromatography is performed on a Shimadzu UPLC instrument. In some embodiments, the size exclusion chromatography is performed at a flow rate of 0.2 mL / min. In some embodiments, the size exclusion chromatography is performed at a column oven temperature of 30° C. In some embodiments, the percentage of monomer is calculated using Shimadzu software. In some embodiments, the size exclusion chromatography is performed as described in Example 2.

[0100] In some embodiments, the antibodies or antigen-binding fragments described herein express at least about 20 μg / ml total antibody. In some embodiments, the antibodies or antigen-binding fragments described herein express about 20 μg / ml to 70 μg / ml total antibody. In some embodiments, the antibodies or antigen-binding fragments are expressed in FreeStyle 293-F cells. In some embodiments, the antibodies or antigen-binding fragments are expressed as described in Example 2. In some embodiments, the expression level of the antibodies or antigen-binding fragments is quantified using an enzyme-linked immunosorbent assay (ELISA). In some embodiments, the ELISA comprises coating the surface of a substrate with a capture antibody that binds to the human or humanized antibody, applying the antibody or antigen-binding fragment to the substrate, and applying a second antibody that binds to the human or humanized antibody to the substrate. In some embodiments, the capture antibody comprises an anti-kappa antibody. In some embodiments, the second antibody comprises an anti-Fc antibody. In some embodiments, the ELISA is performed as described in Example 2.

[0101] Further provided herein is a method for treating inflammatory bowel disease (IBD) in a subject in need thereof, comprising administering to the subject an antibody or antigen-binding fragment described herein. In some embodiments, the IBD comprises Crohn's disease. In some embodiments, the IBD comprises ulcerative colitis. [Brief explanation of the drawings]

[0102] Exemplary embodiments are shown in the referenced drawings, in which: It is intended that the embodiments and drawings disclosed herein be considered illustrative rather than restrictive.

[0103] [Figure 1A] 1A to 1C show chromatograms for analytical size exclusion chromatography of anti-TL1A antibodies. [Figure 1B]1A to 1C show chromatograms for analytical size exclusion chromatography of anti-TL1A antibodies. [Figure 1C] 1A to 1C show chromatograms for analytical size exclusion chromatography of anti-TL1A antibodies. [Figure 2] FIG. 2 shows the inhibition of interferon gamma in human blood by anti-TL1A antibodies. [Figure 3A] Figures 3A-3C show PLS models demonstrating the effect of pH and protein concentration on viscosity. Figure 3A shows the PLS graph. Viscosity units are mPa-s. [Figure 3B] Figures 3A-3C show PLS models demonstrating the effect of pH and protein concentration on viscosity. Figure 3B shows the model predicted viscosity versus anti-TL1A antibody concentration in mg / mL. Viscosity units are mPa-s. [Figure 3C] Figures 3A-3C show PLS models demonstrating the effect of pH and protein concentration on viscosity. Figure 3C shows the model of predicted vs. actual viscosity. Viscosity units are mPa-s. DETAILED DESCRIPTION OF THE INVENTION

[0104] Tumor necrosis factor-like protein 1A (TL1A) is a proinflammatory molecule that stimulates the proliferation and effector function of CD8(+) cytotoxic T cells, as well as Th1, Th2, and Th17 cells, in the presence of TCR stimulation. TL1A has been associated with the progression and severity of inflammatory bowel disease (IBD), such as Crohn's disease (CD) and ulcerative colitis. TL1A is thought to be involved in the pathogenesis of IBD by bridging the innate and adaptive immune responses, regulating adaptive immunity by increasing Th1, Th2, and Th17 effector cell function, as well as T cell accumulation and immunopathology in inflamed tissues. TL1A is a target associated with both intestinal inflammation and intestinal fibrosis, which has been clinically proven in a phase 2a clinical trial in UC. Furthermore, preclinical human genetic association data suggest that TL1A is a potential therapeutic target in CD. The present disclosure describes optimized antibodies against TL1A, providing a novel therapeutic approach for the treatment of IBD. The anti-TL1A antibodies described herein can substantially improve outcomes for patients with moderate to severe IBD who are prone to increased TL1A expression. As an example, patients are selected for treatment with the anti-TL1A antibodies described herein based on increased expression of TL1A in the patient compared to a reference level (e.g., from a subject not suffering from IBD). Patients may be selected for increased TL1A expression to determine the presence of a genotype associated with increased TL1A expression, as determined by a genotyping assay. TL1A (tumor necrosis factor ligand superfamily member 15 (TNFSF15)) and nucleic acids encoding TL1A are provided as identified by Entrez Gene:9966; UniProtKB:095150. Accordingly, the present disclosure further provides methods for treating subjects with increased TL1A expression with the antibodies described herein.

[0105] antibody In one aspect, provided herein are antibodies and antigen-binding fragments. In some embodiments, an antibody includes an antigen-binding fragment, which refers to a portion of an antibody having the antigenic-determining variable region of the antibody. Examples of antigen-binding fragments include, but are not limited to, Fab, Fab', F(ab')2, and Fv fragments, linear antibodies, single-chain antibodies, and multispecific antibodies formed from antibody fragments. In some embodiments, an antibody refers to an immunoglobulin molecule that recognizes and specifically binds to a target, such as a protein, polypeptide, peptide, carbohydrate, polynucleotide, lipid, or a combination of the foregoing, via at least one antigen recognition site within the variable region of the immunoglobulin molecule. In some embodiments, antibodies include intact polyclonal antibodies, intact monoclonal antibodies, antibody fragments (e.g., Fab, Fab', F(ab')2, and Fv fragments), single-chain Fv (scFv) mutants, CDR-grafted antibodies, multispecific antibodies, chimeric antibodies, humanized antibodies, human antibodies, fusion proteins containing an antigen-determining portion of an antibody, and any other modified immunoglobulin molecule containing an antigen recognition site, so long as the antibody exhibits the desired biological activity. Antibodies can belong to any of the five major classes of immunoglobulins: IgA, IgD, IgE, IgG, and IgM, or their subclasses (isotypes) (e.g., IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2), based on the identity of the heavy-chain constant domains designated alpha, delta, epsilon, gamma, and mu, respectively. Different classes of immunoglobulins have well-known distinct subunit structures and three-dimensional configurations. Antibodies can be naked or conjugated to other molecules, eg, toxins, radioisotopes, etc.

[0106] In some embodiments, a humanized antibody refers to a form of a non-human (e.g., murine) antibody having a particular immunoglobulin chain, chimeric immunoglobulin, or fragment thereof that contains minimal non-human (e.g., murine) sequence. In a non-limiting example, a humanized antibody contains less than about 40% non-human sequence within the variable region. In some cases, a humanized antibody contains less than about 20% non-human sequence within the full-length antibody sequence. In a further non-limiting example, a humanized antibody contains less than about 20% non-human sequence within the framework regions of each of the heavy and light chain variable regions. For example, a humanized antibody contains less than about 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, or 1% non-human sequence within the framework regions of each of the heavy and light chain variable regions. As another example, a humanized antibody comprises about 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 or less non-human sequences within the framework regions of each of the heavy and light chain variable regions. In some cases, humanized antibodies are human immunoglobulins in which residues from a complementarity-determining region (CDR) are replaced by residues from a CDR of a non-human species (e.g., mouse, rat, rabbit, hamster) having the desired specificity, affinity, and capacity. These humanized antibodies may contain one or more non-human species mutations, for example, the heavy chain contains about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 non-human species mutations in the framework regions and the light chain contains about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 non-human species mutations in the framework regions. The humanized heavy chain variable domain is an IGHV1-46 antibody with no amino acid mutations or less than about 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 amino acid mutations. * The humanized light chain variable domain may comprise an IGKV3-20 framework with no amino acid mutations or with less than about 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 amino acid mutations.

[0107] In some embodiments, a chimeric antibody refers to an antibody in which the sequences of the immunoglobulin molecule are derived from two or more species. As a non-limiting example, the variable regions of both the light and heavy chains correspond to the variable regions of antibodies derived from one species of mammal (e.g., mouse, rat, rabbit, etc.) having the desired specificity, affinity, and capacity, while the constant regions are homologous to sequences in antibodies derived from another species (usually human) to avoid eliciting an immune response in that species.

[0108] The terms "complementarity-determining region" and "CDR," synonymous with "hypervariable region" or "HVR," are known in the art to refer to non-contiguous sequences of amino acids in an antibody variable region that confer antigen specificity and / or binding affinity. Generally, there are three CDRs (CDR-H1, CDR-H2, CDR-H3) in each heavy chain variable region and three CDRs (CDR-L1, CDR-L2, CDR-L3) in each light chain variable region. The terms "framework region" and "FR" are known in the art to refer to the non-CDR portions of the heavy and light chain variable regions. Generally, there are four FRs (FR-H1, FR-H2, FR-H3, and FR-H4) in each full-length heavy chain variable region and four FRs (FR-L1, FR-L2, FR-L3, and FR-L4) in each full-length light chain variable region.The precise amino acid sequence boundaries of a given CDR or FR can be determined by Kabat et al. (1991), "Sequences of Proteins of Immunological Interest," 5th ed., Public Health Service, National Institutes of Health, Bethesda, MD ("Kabat" numbering scheme); Al-Lazikani et al. (1997), JMB 273, 927-948 ("Chothia" numbering scheme); MacCallum et al., J. Mol. Biol. 262:732-745 (1996), "Antibody-antigen interactions: Contact analysis and binding site topography," J. Mol. Biol. 262, 732-745 ("Contact" numbering scheme); Lefranc MP et al., "IMGT unique numbering for immunoglobulin and T cell receptor variable domains and Ig superfamily V-like domains," Dev Comp Immunol, January 2003; 27(1):55-77 ("IMGT" numbering scheme); Honegger A and Pluckthun A, "Yet another numbering scheme for immunoglobulin variable domains: an automatic modeling and analysis tool," J Mol Biol, June 8, 2001; 309(3):657-70 ("Aho" numbering scheme); and Whitelegg NR and Rees AR, "WAM: an improved algorithm for modeling antibodies on the WEB," Protein Eng. December 2000; 13(12):819-24 ("AbM" numbering scheme).In certain embodiments, the CDRs of the antibodies described herein can be defined by a method selected from Kabat, Chothia, IMGT, Aho, AbM, or a combination thereof.

[0109] In some embodiments, an antibody that specifically binds to a protein indicates that the antibody reacts or associates with the protein more frequently, more rapidly, for a longer period of time, with greater affinity, or some combination of the above, than with other substances, including unrelated proteins.

[0110] In some embodiments, the terms "polypeptide," "peptide," and "protein" are used interchangeably herein to refer to polymers of amino acids of any length. The polymers may be linear or branched, may contain modified amino acids, or may be interrupted by non-amino acids. The terms also encompass amino acid polymers that are modified, either naturally or by intervention; for example, disulfide bond formation, glycosylation, lipidation, acetylation, phosphorylation, or any other manipulation or modification, such as fusion with another polypeptide and / or conjugation with, for example, a labeling component. Also included within the definition are, for example, polypeptides containing one or more analogs of an amino acid, as well as other modifications known in the art (e.g., unnatural amino acids, etc.).

[0111] In some embodiments, proteins such as antibodies described herein comprise hydrophobic amino acids. Non-limiting exemplary hydrophobic amino acids include glycine (Gly), proline (Pro), phenylalanine (Phe), alanine (Ala), isoleucine (Ile), leucine (Leu), and valine (Val). In some embodiments, proteins such as antibodies described herein comprise hydrophilic amino acids. Non-limiting exemplary hydrophilic amino acids include serine (Ser), threonine (Thr), aspartic acid (Asp), glutamic acid (Glu), cysteine ​​(Cys), asparagine (Asn), glutamine (Gln), arginine (Arg), and histidine (His). In some embodiments, proteins such as antibodies described herein comprise amphipathic amino acids. Non-limiting exemplary amphipathic amino acids include lysine (Lys), tryptophan (Trp), tyrosine (Tyr), and methionine (Met). In some embodiments, proteins such as antibodies described herein comprise aliphatic amino acids. Non-limiting exemplary aliphatic amino acids include alanine (Ala), isoleucine (Ile), leucine (Leu), and valine (Val). In some embodiments, proteins such as antibodies described herein comprise aromatic amino acids. Non-limiting exemplary aromatic amino acids include phenylalanine (Phe), tryptophan (Trp), and tyrosine (Tyr). In some embodiments, proteins such as antibodies described herein comprise acidic amino acids. Non-limiting exemplary acidic amino acids include aspartic acid (Asp) and glutamic acid (Glu). In some embodiments, proteins such as antibodies described herein comprise basic amino acids. Non-limiting exemplary basic amino acids include arginine (Arg), histidine (His), and lysine (Lys). In some embodiments, proteins such as antibodies described herein comprise hydroxyl amino acids. Non-limiting exemplary hydroxyl amino acids include serine (Ser) and threonine (Thr). In some embodiments, proteins such as antibodies described herein comprise sulfur-containing amino acids.Non-limiting exemplary sulfur-containing amino acids include cysteine ​​(Cys) and methionine (Met). In some embodiments, proteins such as antibodies described herein contain amide amino acids. Non-limiting exemplary amide amino acids include asparagine (Asn) and glutamine (Gln).

[0112] In some embodiments, "polynucleotide" or "nucleic acid," as used interchangeably herein, refers to a polymer of nucleotides of any length, including DNA and RNA. The nucleotides can be deoxyribonucleotides, ribonucleotides, modified nucleotides or bases, and / or their analogs, or any substrate that can be incorporated into a polymer by DNA or RNA polymerase. A polynucleotide can include modified nucleotides, such as, but not limited to, methylated nucleotides and their analogs, and can include non-nucleotide components. Modifications to the nucleotide structure can be imparted before or after assembly of the polymer. A polynucleotide can be further modified after polymerization, for example, by conjugation with a labeling component.

[0113] The percent sequence identity (%) to a reference polypeptide sequence is the percentage of amino acid residues in a candidate sequence that are identical to those in the reference polypeptide sequence, after aligning the sequences to achieve the maximum percent sequence identity and introducing gaps, if necessary, without considering any conservative substitutions as part of the sequence identity. Alignment to determine percent amino acid sequence identity can be achieved by various known methods, for example, using publicly available computer software such as BLAST, BLAST-2, ALIGN, or Megalign (DNASTAR) software. Appropriate parameters for aligning sequences, including the algorithm required to achieve maximum alignment over the entire length of the sequences to be compared, can be determined. However, for purposes herein, percent amino acid sequence identity values ​​are generated using the sequence comparison computer program ALIGN-2. The ALIGN-2 sequence comparison computer program was created by Genentech, Inc., and the source code is on file with user documentation at the US Copyright Office, Washington DC, 20559, and is registered under US Copyright Registration No. TXU510087. The ALIGN-2 program is publicly available from Genentech, Inc., South San Francisco, Calif., or may be compiled from the source code. The ALIGN-2 program should be compiled for use on UNIX operating systems, including Digital UNIX V4.0D. All sequence comparison parameters are set by the ALIGN-2 program and do not vary.

[0114] In situations where ALIGN-2 is used for amino acid sequence comparison, the % amino acid sequence identity of a given amino acid sequence A to, with, or against a given amino acid sequence B (alternatively, it can be expressed as a given amino acid sequence A having or comprising a particular % amino acid sequence identity to, with, or against a given amino acid sequence B) is calculated as follows: 100 x X / Y, where X is the number of amino acid residues in the program alignment of A and B scored as identical matches by the sequence alignment program ALIGN-2, and Y is the total number of amino acid residues in B. Of course, if the length of amino acid sequence A is not equal to the length of amino acid sequence B, the % amino acid sequence identity of A to B will not equal the % amino acid sequence identity of B to A. Unless specifically stated otherwise, all % amino acid sequence identity values ​​used herein are obtained using the ALIGN-2 computer program, as described in the immediately preceding paragraph.

[0115] In some embodiments, the term "about" means within 10% of the stated amount. For example, an antibody variable region that contains about 80% identity to a reference variable region may contain 72%-88% identity to the reference variable region.

[0116] In certain aspects, an antibody that specifically binds to TL1A (Entrez Gene: 9966; UniProtKB: O95150) is described herein. In some embodiments, the antibody specifically binds to soluble TL1A. In some embodiments, the antibody specifically binds to membrane-bound TL1A. In some embodiments, an anti-TL1A antibody is provided having a heavy chain comprising four heavy chain framework regions (HCFRs) and three heavy chain complementarity-determining regions (HCDRs): HCFR1, HCDR1, HCFR2, HCDR2, HCFR3, HCDR3, and HCFR4; and a light chain comprising four light chain framework regions (LCFRs) and three light chain complementarity-determining regions (LCDRs): LCFR1, LCDR1, LCFR2, LCDR2, LCFR3, LCDR3, and LCFR4. The anti-TL1A antibody may comprise any of the regions provided herein, e.g., as set forth in Tables 6-11, the Examples, and the sequences.

[0117] Exemplary Anti-TL1A CDRs In certain embodiments, the anti-TL1A antibody comprises an HCDR1 represented by SEQ ID NO: 1. In certain embodiments, the anti-TL1A antibody comprises an HCDR2 represented by any one of SEQ ID NOs: 2-5. In certain embodiments, the anti-TL1A antibody comprises an HCDR3 represented by any one of SEQ ID NOs: 6-9. In certain embodiments, the anti-TL1A antibody comprises an LCDR1 represented by SEQ ID NO: 10. In certain embodiments, the anti-TL1A antibody comprises an LCDR2 represented by SEQ ID NO: 11. In certain embodiments, the anti-TL1A antibody comprises an LCDR3 represented by any one of SEQ ID NOs: 12-15.

[0118] In certain embodiments, the anti-TL1A antibody comprises an HCDR1, HCDR2, HCDR3, LCDR1, LCDR2, and LCDR3 selected from Table 6. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody B shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody C shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody D shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody E shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody F shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody G shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody H shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A2 shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody B2 shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody C2 shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody D2 shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody E2 shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody F2 shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody G2 shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody H2 shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody I shown in Table 10. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody I2 shown in Table 10.

[0119] In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in any one of the antibodies in Table 1. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A217, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A220, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A223, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A219, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A221, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A200, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A213, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A212, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A107, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A205, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A211, where the CDRs are defined by the Kabat, Chothia, or IMGT methods.In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A199, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A15, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A30, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A100, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A181, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A129, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A214, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A216, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A122, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A222, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A188, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A203, as defined by the Kabat, Chothia, or IMGT methods.In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A147, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A127, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A126, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A160, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A157, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A159, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A218, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A158, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A125, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A103, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A64, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A67, as defined by the Kabat, Chothia, or IMGT methods.In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A138, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A68, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A94, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A110, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A197, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A112, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A169, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A173, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A179, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A148, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A115, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A149, as defined by the Kabat, Chothia, or IMGT methods.In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A134, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A113, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A151, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A96, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A132, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A196, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A172, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A75, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A174, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs shown in antibody A109, where the CDRs are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A198, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the CDRs set forth in antibody A170, as defined by the Kabat, Chothia, or IMGT methods.

[0120] Exemplary Anti-TL1A Framework Regions Tables 7-9A and 11 list exemplary framework and variable region sequences.

[0121] In some embodiments, the anti-TL1A antibody comprises a heavy chain framework comprising SEQ ID NO: 301 (X1VQLVQSGAEVKKPGASVKVSCKAS[HCDR1]WVX2QX3PGQGLEWX4G[HCDR2]RX5TX6TX7DTSTSTX8YX9ELSSLRSEDTAVYYCAR[HCDR3]WGQGTTVTVSS). In some embodiments, X1 is Q. In some embodiments, X1=E. In some embodiments, X2=R. In some embodiments, X2=K. In some embodiments, X3=A. In some embodiments, X3=R. In some embodiments, X4=M. In some embodiments, X4=I. In some embodiments, X5=V. In some embodiments, X5=A. In some embodiments, X6=M. In some embodiments, X6=I. In some embodiments, X7=R. In some embodiments, X7=T. In some embodiments, X8=V. In some embodiments, X8=A. In some embodiments, X9 = M. In some embodiments, X9 = L. In some embodiments, X1 is IGHV1-46 as determined by Kabat numbering. * In some embodiments, X2 is at position 1 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X3 is at position 45 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X4 is at position 47 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X5 is at position 55 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X6 is at position 78 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X7 is at position 80 of IGHV1-46 as determined by Kabat numbering.* In some embodiments, X8 is at position 82 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X9 is at position 89 of IGHV1-46 as determined by Kabat numbering. * It is ranked 91st in 02.

[0122] In one aspect, provided herein is an IGHV1-46 * 02, or a variant thereof, wherein the variant is IGHV1-46 *This is a first embodiment of an anti-TL1A antibody or variant thereof, comprising about 1 to about 9 amino acid substitutions, or about 1 to about 20 amino acid substitutions, or about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid substitutions from the TL1A. Further embodiments include (2) the anti-TL1A of embodiment (1), wherein the heavy chain framework comprises SEQ ID NO: 301. (3) the anti-TL1A of embodiment 2, wherein X1=Q. (4) the anti-TL1A of embodiment 2, wherein X1=E. (5) the anti-TL1A of any one of embodiments 2-4, wherein X2=R. (6) the anti-TL1A of any one of embodiments 2-4, wherein X2=K. (7) the anti-TL1A of any one of embodiments 2-6, wherein X3=A. (8) the anti-TL1A of any one of embodiments 2-6, wherein X3=R. (9) Anti-TL1A of any one of embodiments 2 to 8, wherein X4 = M. (10) Anti-TL1A of any one of embodiments 2 to 8, wherein X4 = I. (11) Anti-TL1A of any one of embodiments 2 to 10, wherein X5 = V. (12) Anti-TL1A of any one of embodiments 2 to 10, wherein X5 = A. (13) Anti-TL1A of any one of embodiments 2 to 12, wherein X6 = M. (14) Anti-TL1A of any one of embodiments 2 to 12, wherein X6 = I. (15) Anti-TL1A of any one of embodiments 2 to 14, wherein X7 = R. (16) Anti-TL1A of any one of embodiments 2 to 14, wherein X7 = T. (17) Anti-TL1A of any one of embodiments 2 to 16, wherein X8 = V. (18) Anti-TL1A of any one of embodiments 2 to 16, wherein X8 = A. (19) The anti-TL1A of any one of embodiments 2 to 18, wherein X9=M. (20) The anti-TL1A of any one of embodiments 2 to 4, wherein X9=L. (21) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody A. (22) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody B. (23) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody C. (24) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody D. (25) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody E. (26) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody F. (27) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody G or I.(28) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody H. (29) An antibody selected from the group consisting of (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, or 329R, (k) 331S, (l ) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, if (ii) 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G,(yy) L234F, L235E, and P331S, (zz) L234A, L235E, and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) 29. The anti-TL1A of any one of embodiments 1-28, comprising a human IgG1 Fc region comprising: G236R and L328R, (eee)G237A, (fff)F241A, (ggg)V264A, (hhh)D265A, (iii)D265A and N297A, (jjj)D265A and N297G, (kkk)D270A, (lll)A330L, (mmm)P331A or P331S, or (nnn) any combination of (a)-(uu). As used herein, a group, e.g., any combination of (a)-(uu), includes at least about two or more items from the group, e.g., any combination of groups (a)-(uu) includes 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, and up to 47, or all, of the group members. (30) The anti-TL1A of any one of embodiments 1 to 28, comprising (i) a human IgG4 Fc region or (ii) a human IgG4 Fc region, wherein the Fc region comprises (a) S228P, (b) S228P and L235E, or (c) S228P, F234A, and L235A according to the Kabat numbering. (31) The anti-TL1A of any one of embodiments 1 to 28, comprising a human IgG2 Fc region; an IgG2-IgG4 cross-subclass Fc region; an IgG2-IgG3 cross-subclass Fc region; an IgG2 comprising H268Q, V309L, A330S, P331S (IgG2m4); or an IgG2 comprising V234A, G237A, P238S, H268A, V309L, A330S, P331S (IgG2σ). (32) The anti-TL1A of any one of embodiments 1 to 31, comprising a heavy chain Fc region comprising any one of SEQ ID NOs: 320 to 362. (33) The anti-TL1A of any one of embodiments 1 to 31, comprising a light chain constant region comprising SEQ ID NO: 319.Anti-TL1A of any one of embodiments 1 to 32. (34) IGKV3-20, * 01, wherein the variant comprises about 1 to about 2 substitutions, or about 1 to about 20 amino acid substitutions, or about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid substitutions within the framework. (35) The anti-TL1A antibody of embodiment 34, wherein X10 is L. (36) The anti-TL1A antibody of embodiment 34, wherein X10 is P. (37) The anti-TL1A antibody of any one of embodiments 34 to 36, wherein X11 is L. (38) The anti-TL1A antibody of any one of embodiments 34 to 36, wherein X11 is W.

[0123] In some embodiments, the anti-TL1A antibody comprises a heavy chain framework comprising SEQ ID NO: 302 (X1VQLVQSGAEVKKPGASVKVSCKAS[HCDR1]WVX2QX3PGQGLEWX4G[HCDR2]RX5TX6TX7DTSTSTX8YX9ELSSLRSEDTAVYYC[HCDR3]WGQGTTVTVSS). In some embodiments, X1 is Q. In some embodiments, X1=E. In some embodiments, X2=R. In some embodiments, X2=K. In some embodiments, X3=A. In some embodiments, X3=R. In some embodiments, X4=M. In some embodiments, X4=I. In some embodiments, X5=V. In some embodiments, X5=A. In some embodiments, X6=M. In some embodiments, X6=I. In some embodiments, X7=R. In some embodiments, X7=T. In some embodiments, X8=V. In some embodiments, X8=A. In some embodiments, X9 = M. In some embodiments, X9 = L. In some embodiments, X1 is IGHV1-46 as determined by Kabat numbering. * In some embodiments, X2 is at position 1 of IGHV1-46 as determined by Kabat numbering. *In some embodiments, X3 is at position 45 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X4 is at position 47 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X5 is at position 55 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X6 is at position 78 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X7 is at position 80 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X8 is at position 82 of IGHV1-46 as determined by Kabat numbering. * In some embodiments, X9 is at position 89 of IGHV1-46 as determined by Kabat numbering. * It is ranked 91st in 02.

[0124] In one aspect, provided herein is an IGHV1-46 * 02, wherein the variant is an anti-TL1A antibody or a variant thereof comprising a heavy chain framework comprising IGHV1-46 *

[0023] Another first embodiment of an anti-TL1A antibody or variant thereof comprises about 1 to about 9 amino acid substitutions, or about 1 to about 20 amino acid substitutions, or about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid substitutions from the TL1A heavy chain framework. Further embodiments include (2) the anti-TL1A of embodiment (1), wherein the heavy chain framework comprises SEQ ID NO: 302. (3) the anti-TL1A of embodiment 2, wherein X1 = Q. (4) the anti-TL1A of embodiment 2, wherein X1 = E. (5) the anti-TL1A of any one of embodiments 2-4, wherein X2 = R. (6) the anti-TL1A of any one of embodiments 2-4, wherein X2 = K. (7) the anti-TL1A of any one of embodiments 2-6, wherein X3 = A. (8) the anti-TL1A of any one of embodiments 2-6, wherein X3 = R. (9) Anti-TL1A of any one of embodiments 2 to 8, wherein X4 = M. (10) Anti-TL1A of any one of embodiments 2 to 8, wherein X4 = I. (11) Anti-TL1A of any one of embodiments 2 to 10, wherein X5 = V. (12) Anti-TL1A of any one of embodiments 2 to 10, wherein X5 = A. (13) Anti-TL1A of any one of embodiments 2 to 12, wherein X6 = M. (14) Anti-TL1A of any one of embodiments 2 to 12, wherein X6 = I. (15) Anti-TL1A of any one of embodiments 2 to 14, wherein X7 = R. (16) Anti-TL1A of any one of embodiments 2 to 14, wherein X7 = T. (17) Anti-TL1A of any one of embodiments 2 to 16, wherein X8 = V. (18) Anti-TL1A of any one of embodiments 2 to 16, wherein X8 = A. (19) The anti-TL1A of any one of embodiments 2 to 18, wherein X9=M. (20) The anti-TL1A of any one of embodiments 2 to 4, wherein X9=L. (21) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody A. (22) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody B. (23) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody C. (24) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody D. (25) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody E. (26) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody F. (27) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody G or I.(28) The anti-TL1A of any one of embodiments 1 to 20, comprising antibody H. (29) An antibody selected from the group consisting of (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, or 329R, (k) 331S, (l ) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, if (ii) 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G,(yy) L234F, L235E, and P331S, (zz) L234A, L235E, and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) (30) The anti-TL1A of any one of embodiments 1 to 28, comprising a human IgG1 Fc region comprising: G236R and L328R, (eee) G237A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of (a)-(uu). (31) The anti-TL1A of any one of embodiments 1 to 28, comprising: (i) a human IgG4 Fc region or (ii) a human IgG4 Fc region comprising: (a) S228P and L235E, or (b) S228P, F234A, and L235A according to the Kabat numbering. (31) The anti-TL1A of any one of embodiments 1 to 28, comprising a human IgG2 Fc region; an IgG2-IgG4 cross-subclass Fc region; an IgG2-IgG3 cross-subclass Fc region; an IgG2 comprising H268Q, V309L, A330S, P331S (IgG2m4); or an IgG2 comprising V234A, G237A, P238S, H268A, V309L, A330S, P331S (IgG2σ). (32) The anti-TL1A of any one of embodiments 1 to 31, comprising a heavy chain Fc region comprising any one of SEQ ID NOs: 320 to 362. (33) The anti-TL1A of any one of embodiments 1 to 32, comprising a light chain constant region comprising SEQ ID NO: 319. (34) IGKV3-20, *01, wherein the variant comprises about 1 to about 2 substitutions, or about 1 to about 20 amino acid substitutions, or about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid substitutions within the framework. (35) The anti-TL1A antibody of embodiment 34, wherein X10 is L. (36) The anti-TL1A antibody of embodiment 34, wherein X10 is P. (37) The anti-TL1A antibody of any one of embodiments 34 to 36, wherein X11 is L. (38) The anti-TL1A antibody of any one of embodiments 34 to 36, wherein X11 is W.

[0125] In some embodiments, the anti-TL1A antibody comprises a light chain framework comprising SEQ ID NO: 303 (EIVLTQSPGTLSLSPGERATLSC[LCDR1]WYQQKPGQAPRX10X11IY[LCDR2]GIPDRFSGSGSGTDFTLTISRLEPEDFAVYYC[LCDR3]FGGGTKLEIK). In some embodiments, X10 is L. In some embodiments, X10 is P. In some embodiments, X11 is L. In some embodiments, X11 is W. In some embodiments, X10 ... * In some embodiments, X11 is at position 54 of IGKV3-20 as determined by Kabat numbering. * It is ranked 55th in 01.

[0126] In some embodiments, the anti-TL1A antibody is IGHV1-46 * 02. In some embodiments, the anti-TL1A antibody comprises an IGHV1-46 heavy chain framework comprising about 1 to about 20 amino acid substitutions from SEQ ID NO: 316. * In some embodiments, the anti-TL1A antibody comprises a heavy chain framework comprising a variant of SEQ ID NO: 316. In some embodiments, the anti-TL1A antibody comprises an IGHV1-46 heavy chain framework comprising about 1 to about 9 amino acid substitutions from SEQ ID NO: 316. *In some embodiments, the anti-TL1A antibody comprises an IGHV1-46 heavy chain framework comprising a variant of SEQ ID NO: 316. In some embodiments, the anti-TL1A antibody comprises an IGHV1-46 heavy chain framework comprising about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid substitutions within the framework from SEQ ID NO: 316. * 02 variant. Optionally, the heavy chain framework substitution includes Q1E as determined by Kabat numbering. Optionally, the heavy chain framework substitution includes R45K as determined by Kabat numbering. Optionally, the heavy chain framework substitution includes A47R as determined by Kabat numbering. Optionally, the heavy chain framework substitution includes M55I as determined by Kabat numbering. Optionally, the heavy chain framework substitution includes V78A as determined by Kabat numbering. Optionally, the heavy chain framework substitution includes M80I as determined by Kabat numbering. Optionally, the heavy chain framework substitution includes R82T as determined by Kabat numbering. Optionally, the heavy chain framework substitution includes V89A as determined by Kabat numbering. Optionally, the heavy chain framework substitution includes M91L as determined by Kabat numbering.

[0127] In some embodiments, the anti-TL1A antibody is IGKV3-20 * 01. In some embodiments, the anti-TL1A antibody comprises an IGKV3-20 light chain framework comprising about 1 to about 20 amino acid substitutions from SEQ ID NO: 317. * In some embodiments, the anti-TL1A antibody comprises a variant of IGKV3-20 comprising about one amino acid substitution from SEQ ID NO: 317. * In some embodiments, the anti-TL1A antibody comprises a variant of IGKV3-20 comprising about two amino acid substitutions from SEQ ID NO: 317. *In some embodiments, the anti-TL1A antibody comprises an IGKV3-20 light chain framework comprising a variant of SEQ ID NO: 317. In some embodiments, the anti-TL1A antibody comprises an IGKV3-20 light chain framework comprising about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid substitutions within the framework from SEQ ID NO: 317. * 01. In some cases, the light chain framework substitution comprises Q1E as determined by Kabat numbering. In some cases, the light chain framework substitution comprises R45K as determined by Kabat numbering.

[0128] In some embodiments, the anti-TL1A antibody comprises a heavy chain FR1 set forth in SEQ ID NO: 304. In some embodiments, the anti-TL1A antibody comprises a heavy chain FR2 set forth in SEQ ID NO: 305. In some embodiments, the anti-TL1A antibody comprises a heavy chain FR2 set forth in SEQ ID NO: 313. In some embodiments, the anti-TL1A antibody comprises a heavy chain FR3 set forth in SEQ ID NO: 306. In some embodiments, the anti-TL1A antibody comprises a heavy chain FR3 set forth in SEQ ID NO: 307. In some embodiments, the anti-TL1A antibody comprises a heavy chain FR3 set forth in SEQ ID NO: 314. In some embodiments, the anti-TL1A antibody comprises a heavy chain FR3 set forth in SEQ ID NO: 315. In some embodiments, the anti-TL1A antibody comprises a heavy chain FR4 set forth in SEQ ID NO: 308. In some embodiments, the anti-TL1A antibody comprises a light chain FR1 set forth in SEQ ID NO: 309. In some embodiments, the anti-TL1A antibody comprises a light chain FR2 set forth in SEQ ID NO: 310. In some embodiments, the anti-TL1A antibody comprises a light chain FR3 set forth in SEQ ID NO: 311. In some embodiments, the anti-TL1A antibody comprises a light chain FR4 set forth by SEQ ID NO:312.

[0129] In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in any one of the antibodies in Table 1, where the framework regions are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in antibody A217, where the framework regions are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in antibody A220, where the framework regions are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in antibody A223, where the framework regions are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in antibody A219, where the framework regions are defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A221, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A200, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A213, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A212, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A107, as defined by the Kabat, Chothia, or IMGT methods.In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A205, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A211, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A199, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A15, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A30, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A100, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A181, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A129, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A214, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A216, as defined by the Kabat, Chothia, or IMGT methods.In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A122, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A222, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A188, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A203, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A147, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A127, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A126, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A160, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A157, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A159, as defined by the Kabat, Chothia, or IMGT methods.In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A218, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A158, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A125, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A103, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A64, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A67, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A138, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A68, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A94, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A110, as defined by the Kabat, Chothia, or IMGT methods.In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A197, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A112, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A169, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A173, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A179, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A148, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A115, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A149, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A134, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A113, as defined by the Kabat, Chothia, or IMGT methods.In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in antibody A151, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in antibody A96, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in antibody A132, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in antibody A196, as defined by the Kabat, Chothia, or IMGT methods. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A172, where the framework regions are defined by the Kabat, Chothia, or IMGT method. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A75, where the framework regions are defined by the Kabat, Chothia, or IMGT method. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A174, where the framework regions are defined by the Kabat, Chothia, or IMGT method. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A109, where the framework regions are defined by the Kabat, Chothia, or IMGT method. In certain embodiments, the anti-TL1A antibody comprises the framework regions shown in antibody A198, where the framework regions are defined by the Kabat, Chothia, or IMGT method. In certain embodiments, the anti-TL1A antibody comprises the framework regions set forth in antibody A170, as defined by the Kabat, Chothia, or IMGT methods.

[0130] Exemplary Anti-TL1A Variable Regions In one aspect, provided herein is an anti-TL1A antibody comprising a heavy chain variable region comprising an amino acid sequence at least about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 101-135; and a light chain variable region at least about 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 201-206.

[0131] Further provided herein is a first embodiment of an anti-TL1A antibody comprising a heavy chain variable region and a light chain variable region. Non-limiting further embodiments include: (Embodiment 2) the anti-TL1A antibody of Embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 101; (Embodiment 3) the anti-TL1A antibody of Embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 101; (Embodiment 4) the anti-TL1A antibody of Embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 101; (Embodiment 5) the anti-TL1A antibody of Embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 102. (Embodiment 6) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 102. (Embodiment 7) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 102. (Embodiment 8) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 103. (Embodiment 9) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 103. (Embodiment 10) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 103.

[0132] (Embodiment 11) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 104. (Embodiment 12) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 104. (Embodiment 13) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 104. (Embodiment 14) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 105. (Embodiment 15) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 105. (Embodiment 16) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 105. (Embodiment 17) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 106. (Embodiment 18) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 106. (Embodiment 19) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 106. (Embodiment 20) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 107. (Embodiment 21) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 107. (Embodiment 22) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 107.

[0133] (Embodiment 23) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 108. (Embodiment 24) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 108. (Embodiment 25) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 108. (Embodiment 26) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 109. (Embodiment 27) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 109. (Embodiment 28) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 109. (Embodiment 29) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 110. (Embodiment 30) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 110. (Embodiment 31) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 110. (Embodiment 32) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 111. (Embodiment 33) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 111. (Embodiment 34) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 111. (Embodiment 35) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 112. (Embodiment 36) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 112.(Embodiment 37) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 112. (Embodiment 38) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 113. (Embodiment 39) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 113. (Embodiment 40) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 113.

[0134] (Embodiment 41) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 114. (Embodiment 42) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 114. (Embodiment 43) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 114. (Embodiment 44) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 115. (Embodiment 45) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 115. (Embodiment 46) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 115. (Embodiment 47) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 116. (Embodiment 48) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 116. (Embodiment 49) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 116. (Embodiment 50) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 117. (Embodiment 51) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 117. (Embodiment 52) ​​The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 117.

[0135] (Embodiment 53) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 118. (Embodiment 54) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 118. (Embodiment 55) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 118. (Embodiment 56) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 119. (Embodiment 57) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 119. (Embodiment 58) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 119. (Embodiment 59) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 120. (Embodiment 60) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 120. (Embodiment 61) The anti-TL1A antibody of embodiment 1, comprising a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 120.

[0136] (Embodiment 62) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 121. (Embodiment 63) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 121. (Embodiment 64) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 121. (Embodiment 65) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 122. (Embodiment 66) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 122. (Embodiment 67) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 122. (Embodiment 68) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 123. (Embodiment 69) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 123. (Embodiment 70) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 123. (Embodiment 71) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 124. (Embodiment 72) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 124. (Embodiment 73) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 124.

[0137] (Embodiment 74) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 125. (Embodiment 75) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 125. (Embodiment 76) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 125. (Embodiment 77) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 126. (Embodiment 78) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 126. (Embodiment 79) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 126. (Embodiment 80) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 127. (Embodiment 81) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 127. (Embodiment 82) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 127. (Embodiment 83) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 128. (Embodiment 84) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 128. (Embodiment 85) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 128.

[0138] (Embodiment 86) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 129. (Embodiment 87) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 129. (Embodiment 88) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 129. (Embodiment 89) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 130. (Embodiment 90) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 130. (Embodiment 91) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 130. (Embodiment 92) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 131. (Embodiment 93) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 131. (Embodiment 94) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 131. (Embodiment 95) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 132. (Embodiment 96) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 132. (Embodiment 97) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 132.

[0139] (Embodiment 98) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 133. (Embodiment 99) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 133. (Embodiment 100) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 133. (Embodiment 101) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 134. (Embodiment 102) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 134. (Embodiment 103) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 134. (Embodiment 104) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises SEQ ID NO: 135. (Embodiment 105) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 135. (Embodiment 106) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 135.

[0140] (Embodiment 107) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises SEQ ID NO: 201. (Embodiment 108) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 109) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 201. (Embodiment 110) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises SEQ ID NO: 202. (Embodiment 111) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 202. (Embodiment 112) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 202. (Embodiment 113) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises SEQ ID NO: 203. (Embodiment 114) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 203. (Embodiment 115) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 203. (Embodiment 116) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises SEQ ID NO: 204. (Embodiment 117) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204. (Embodiment 118) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 204.(Embodiment 119) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises SEQ ID NO: 205. (Embodiment 120) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. (Embodiment 121) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 205. (Embodiment 122) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises SEQ ID NO: 206. (Embodiment 123) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 206. (Embodiment 124) The anti-TL1A antibody of any one of embodiments 1 to 106, wherein the light chain variable region comprises a sequence having about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 amino acid substitutions or deletions compared to SEQ ID NO: 206.

[0141] (Embodiment 125) The anti-TL1A antibody of embodiment 1, comprising A217. (Embodiment 126) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 101, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 127) The anti-TL1A antibody of embodiment 1, comprising A220. (Embodiment 128) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 102, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 129) The anti-TL1A antibody of embodiment 1, comprising A223. (Embodiment 130) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 103, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 202. (Embodiment 131) The anti-TL1A antibody of embodiment 1, comprising A219. (Embodiment 132) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 104, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 133) The anti-TL1A antibody of embodiment 1, comprising A221. (Embodiment 134) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 105, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201.

[0142] (Embodiment 135) The anti-TL1A antibody of embodiment 1, comprising A200. (Embodiment 136) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 103, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 137) The anti-TL1A antibody of embodiment 1, comprising A213. (Embodiment 138) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 106, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 201. (Embodiment 139) The anti-TL1A antibody of embodiment 1, comprising A212. (Embodiment 140) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 107, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 202. (Embodiment 141) The anti-TL1A antibody of embodiment 1, comprising A107. (Embodiment 142) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 108, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 202. (Embodiment 143) The anti-TL1A antibody of embodiment 1, comprising A205. (Embodiment 144) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 109, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 202.

[0143] (Embodiment 145) The anti-TL1A antibody of embodiment 1, comprising A211. (Embodiment 146) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 108, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 147) The anti-TL1A antibody of embodiment 1, comprising A199. (Embodiment 148) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 109, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 201. (Embodiment 149) The anti-TL1A antibody of embodiment 1, comprising A15. (Embodiment 150) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 108, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 203. (Embodiment 151) The anti-TL1A antibody of embodiment 1, comprising A30. (Embodiment 152) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 108, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204. (Embodiment 153) The anti-TL1A antibody of embodiment 1, comprising A100. (Embodiment 154) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 107, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204.

[0144] (Embodiment 155) The anti-TL1A antibody of embodiment 1, comprising A181. (Embodiment 156) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 107, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 202. (Embodiment 157) The anti-TL1A antibody of embodiment 1, comprising A129. (Embodiment 158) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 110, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 204. (Embodiment 159) The anti-TL1A antibody of embodiment 1, comprising A214. (Embodiment 160) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 111, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 201. (Embodiment 161) The anti-TL1A antibody of embodiment 1, comprising A216. (Embodiment 162) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 112, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 163) The anti-TL1A antibody of embodiment 1, comprising A122. (Embodiment 164) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 113, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204.

[0145] (Embodiment 165) The anti-TL1A antibody of embodiment 1, comprising A222. (Embodiment 166) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 114, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 167) The anti-TL1A antibody of embodiment 1, comprising A188. (Embodiment 168) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 115, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 202. (Embodiment 169) The anti-TL1A antibody of embodiment 1, comprising A203. (Embodiment 170) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 116, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 201. (Embodiment 171) The anti-TL1A antibody of embodiment 1, comprising A147. (Embodiment 172) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 117, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 173) The anti-TL1A antibody of embodiment 1, comprising A127. (Embodiment 174) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 118, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204.

[0146] (Embodiment 175) The anti-TL1A antibody of embodiment 1, comprising A126. (Embodiment 176) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 114, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204. (Embodiment 177) The anti-TL1A antibody of embodiment 1, comprising A160. (Embodiment 178) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 102, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 204. (Embodiment 179) The anti-TL1A antibody of embodiment 1, comprising A157. (Embodiment 180) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 104, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 204. (Embodiment 181) The anti-TL1A antibody of embodiment 1, comprising A159. (Embodiment 182) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 119, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204. (Embodiment 183) The anti-TL1A antibody of embodiment 1, comprising A218. (Embodiment 184) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 119, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201.

[0147] (Embodiment 185) The anti-TL1A antibody of embodiment 1, comprising A158. (Embodiment 186) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 101, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204. (Embodiment 187) The anti-TL1A antibody of embodiment 1, comprising A125. (Embodiment 188) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 105, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 204. (Embodiment 189) The anti-TL1A antibody of embodiment 1, comprising A103. (Embodiment 190) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 120, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 204. (Embodiment 191) The anti-TL1A antibody of embodiment 1, comprising A64. (Embodiment 192) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 121, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 202. (Embodiment 193) The anti-TL1A antibody of embodiment 1, comprising A67. (Embodiment 194) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 122, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 202.

[0148] (Embodiment 195) The anti-TL1A antibody of embodiment 1, comprising A138. (Embodiment 196) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 122, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 204. (Embodiment 197) The anti-TL1A antibody of embodiment 1, comprising A68. (Embodiment 198) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 123, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 202. (Embodiment 199) The anti-TL1A antibody of embodiment 1, comprising A94. (Embodiment 200) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 124, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 202. (Embodiment 201) The anti-TL1A antibody of embodiment 1, comprising A110. (Embodiment 202) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 125, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. (Embodiment 203) The anti-TL1A antibody of embodiment 1, comprising A197. (Embodiment 204) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 116, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205.

[0149] (Embodiment 205) The anti-TL1A antibody of embodiment 1, comprising A112. (Embodiment 206) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 117, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. (Embodiment 207) The anti-TL1A antibody of embodiment 1, comprising A169. (Embodiment 208) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 126, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 205. (Embodiment 209) The anti-TL1A antibody of embodiment 1, comprising A173. (Embodiment 210) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 127, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 205. (Embodiment 211) The anti-TL1A antibody of embodiment 1, comprising A179. (Embodiment 212) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 127, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201. (Embodiment 213) The anti-TL1A antibody of embodiment 1, comprising A148. (Embodiment 214) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 121, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201.

[0150] (Embodiment 215) The anti-TL1A antibody of embodiment 1, comprising A115. (Embodiment 216) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 122, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. (Embodiment 217) The anti-TL1A antibody of embodiment 1, comprising A149. (Embodiment 218) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 122, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 201. (Embodiment 219) The anti-TL1A antibody of embodiment 1, comprising A134. (Embodiment 220) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 122, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 206. (Embodiment 221) The anti-TL1A antibody of embodiment 1, comprising A113. (Embodiment 222) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 124, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. (Embodiment 223) The anti-TL1A antibody of embodiment 1, comprising A151. (Embodiment 224) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 124, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 201.

[0151] (Embodiment 225) The anti-TL1A antibody of embodiment 1, comprising A96. (Embodiment 226) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 128, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. (Embodiment 227) The anti-TL1A antibody of embodiment 1, comprising A132. (Embodiment 228) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 128, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 206. (Embodiment 229) The anti-TL1A antibody of embodiment 1, comprising A196. (Embodiment 230) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 129, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 205. (Embodiment 231) The anti-TL1A antibody of embodiment 1, comprising A172. (Embodiment 232) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 130, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. (Embodiment 233) The anti-TL1A antibody of embodiment 1, comprising A75. (Embodiment 234) An anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 131, and the light chain variable region comprises an array at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205.

[0152] (Embodiment 235) The anti-TL1A antibody of embodiment 1, comprising A174. (Embodiment 236) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 132, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. (Embodiment 237) The anti-TL1A antibody of embodiment 1, comprising A109. (Embodiment 238) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 133, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 205. (Embodiment 239) The anti-TL1A antibody of embodiment 1, comprising A198. (Embodiment 240) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 134, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99% or 100% identical to SEQ ID NO: 205. (Embodiment 241) The anti-TL1A antibody of embodiment 1, comprising A170. (Embodiment 242) The anti-TL1A antibody of embodiment 1, wherein the heavy chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 135, and the light chain variable region comprises a sequence at least about 90%, 95%, 96%, 97%, 98%, 99%, or 100% identical to SEQ ID NO: 205. (Embodiment 243) The anti-TL1A antibody of embodiment 1, comprising A500. (Embodiment 244) The anti-TL1A antibody of embodiment 1, comprising A501.

[0153] (Embodiment 245) According to the Kabat numbering, (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A , 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G, (yy) L234F, L235E, and P331S, (zz) L234A, L235E, and G237A,(aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (eee) G237A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of (a) to (uu). (Embodiment 246) The anti-TL1A of any one of embodiments 1 to 244, comprising (i) a human IgG4 Fc region or (ii) a human IgG4 Fc region comprising: (a) S228P and L235E, or (b) S228P, F234A, and L235A according to the Kabat numbering. (Embodiment 247) The anti-TL1A of any one of embodiments 1 to 244, comprising a human IgG2 Fc region; an IgG2-IgG4 cross-subclass Fc region; an IgG2-IgG3 cross-subclass Fc region; an IgG2 comprising H268Q, V309L, A330S, P331S (IgG2m4); or an IgG2 comprising V234A, G237A, P238S, H268A, V309L, A330S, P331S (IgG2σ). (Embodiment 248) The anti-TL1A of any one of embodiments 1 to 247, comprising a heavy chain Fc region comprising any one of SEQ ID NOs: 320 to 362. (Embodiment 249) The anti-TL1A of any one of embodiments 1 to 248, comprising a light chain constant region comprising SEQ ID NO: 319.

[0154] (Embodiment 250) The anti-TL1A of any one of embodiments 1 to 249, comprising a monomer fraction of at least about 80%, as determined by the size exclusion chromatography method described herein. (Embodiment 251) The anti-TL1A of any one of embodiments 1 to 250, comprising a monomer fraction of at least about 81%, at least about 82%, at least about 83%, or at least about 84%, as determined by the size exclusion chromatography method described herein. (Embodiment 252) The anti-TL1A of any one of embodiments 1 to 251, comprising a monomer fraction of at least about 85%, as determined by the size exclusion chromatography method described herein. (Embodiment 253) The anti-TL1A of any one of embodiments 1 to 252, comprising a monomer fraction of at least about 86%, at least about 87%, at least about 88%, or at least about 89%, as determined by the size exclusion chromatography method described herein. (Embodiment 254) The anti-TL1A of any one of embodiments 1 to 253, comprising at least about 90% of the monomer fraction, as determined by the size exclusion chromatography method described herein. (Embodiment 255) The anti-TL1A of any one of embodiments 1 to 254, comprising at least about 91%, at least about 92%, at least about 93%, or at least about 94% of the monomer fraction, as determined by the size exclusion chromatography method described herein. (Embodiment 256) The anti-TL1A of any one of embodiments 1 to 255, comprising at least about 95% of the monomer fraction, as determined by the size exclusion chromatography method described herein. (Embodiment 257) The anti-TL1A of any one of embodiments 1 to 256, comprising at least about 96%, at least about 97%, at least about 98%, or at least about 99% of the monomer fraction, as determined by the size exclusion chromatography method described herein.

[0155] (Embodiment 258) The anti-TL1A of any one of embodiments 1 to 257, comprising an expression of at least about 2 μg / mL, as determined by the methods disclosed herein. (Embodiment 259) The anti-TL1A of any one of embodiments 1 to 258, comprising an expression of about 2 μg / mL to about 60 μg / mL, as determined by the methods disclosed herein. (Embodiment 260) The anti-TL1A of any one of embodiments 1 to 259, comprising an expression of about 5 μg / mL to about 60 μg / mL, as determined by the methods disclosed herein. (Embodiment 261) The anti-TL1A of any one of embodiments 1 to 260, comprising an expression of about 10 μg / mL to about 60 μg / mL, as determined by the methods disclosed herein. (Embodiment 262) The anti-TL1A of any one of embodiments 1 to 261, comprising an expression of at least about 5 μg / mL, as determined by the methods disclosed herein. (Embodiment 263) The anti-TL1A of any one of embodiments 1 to 262, comprising an expression of at least about 10 μg / mL, as determined by the methods disclosed herein. (Embodiment 264) The anti-TL1A of any one of embodiments 1 to 263, comprising an expression of at least about 15 μg / mL, as determined by the methods disclosed herein. (Embodiment 265) The anti-TL1A of any one of embodiments 1 to 264, comprising an expression of at least about 20 μg / mL, as determined by the methods disclosed herein.

[0156] Exemplary Anti-TL1A Constant Regions In some embodiments, one or more amino acid modifications may be introduced into the crystallizable fragment (Fc) region of a human or humanized antibody to produce an Fc region variant. The Fc region may include the C-terminal region of an immunoglobulin heavy chain, including the hinge region, CH2 domain, CH3 domain, or any combination thereof. As used herein, Fc region includes native-sequence Fc regions and variant Fc regions. An Fc region variant may comprise a human Fc region sequence (e.g., a human IgG1, IgG2, IgG3, or IgG4 Fc region) containing an amino acid modification (e.g., substitution, addition, or deletion) at one or more amino acid positions. In an exemplary embodiment, the Fc region comprises any one of SEQ ID NOs: 320-362.

[0157] In some embodiments, the antibodies of the present disclosure have reduced effector functions compared to human IgG. Effector function refers to biological events resulting from the interaction of an antibody Fc region with an Fc receptor or ligand. Non-limiting effector functions include C1q binding, complement-dependent cytotoxicity (CDC), Fc receptor binding, antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), cytokine secretion, immune complex-mediated antigen absorption by antigen-presenting cells, downregulation of cell surface receptors (e.g., B cell receptors), and B cell activation. In some cases, antibody-dependent cell-mediated cytotoxicity (ADCC) refers to a cell-mediated reaction in which nonspecific cytotoxic cells expressing Fc receptors (e.g., natural killer cells, neutrophils, macrophages) recognize bound antibodies on target cells and then cause lysis of the target cells. In some cases, complement-dependent cytotoxicity (CDC) refers to the lysis of target cells in the presence of complement, where the complement pathway is initiated by the binding of C1q to target-bound antibodies.

[0158] Some Fc regions naturally lack effector function, and some Fc regions may contain mutations that reduce effector function, for example, IgG4 has low ADCC and CDC activity, and IgG2 has low ADCC activity.

[0159] The present disclosure provides antibodies comprising a non-variant Fc region, i.e., antibodies comprising an Fc region characterized by exhibiting reduced ADCC by at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, or more compared to an antibody with the same sequence identity (e.g., human IgG1, SEQ ID NO: 320), but not by substitutions that reduce ADCC. The present disclosure provides antibodies comprising a non-variant Fc region, i.e., antibodies comprising an Fc region characterized by exhibiting reduced CDC by at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, or more compared to an antibody with the same sequence identity (e.g., human IgG1, SEQ ID NO: 320), but not by substitutions that reduce CDC. In certain embodiments, antibodies of the present disclosure have reduced effector function compared to human IgG1. Measurement of effector function may be performed as described in Example 3.

[0160] Non-limiting examples of Fc mutations within IgG1 that may reduce ADCC and / or CDC include substitutions at one or more of positions 231, 232, 234, 235, 236, 237, 238, 239, 264, 265, 267, 269, 270, 297, 299, 318, 320, 322, 325, 327, 328, 329, 330, and 331 within IgG1, where the numbering system for the constant region is that of the EU index as set forth by Kabat. In certain embodiments, antibodies of the present disclosure have reduced effector function compared to human IgG1.

[0161] In some embodiments, the antibody comprises an IgG1 Fc region comprising an N297A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an N297Q substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an N297D substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a D265A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an S228P substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an L235A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an L237A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an L234A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an E233P substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an L234V substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a C236 deletion according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a P238A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an A327Q substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a P329A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a P329G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising an L235E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a P331S substitution according to the Kabat numbering system.In some embodiments, the antibody comprises an IgG1 Fc region comprising an L234F substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 235G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 235Q substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 235R substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 235S substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 236F substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 236R substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 237E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 237K substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 237N substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 237R substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 238A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 238E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 238G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 238H substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 238I substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 238V substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 238W substitution according to the Kabat numbering system.In some embodiments, the antibody comprises an IgG1 Fc region comprising a 238Y substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 248A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254D substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254H substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254I substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254N substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254P substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254Q substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254T substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 254V substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 255N substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 256H substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 256K substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 256R substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 256V substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 264S substitution according to the Kabat numbering system.In some embodiments, the antibody comprises an IgG1 Fc region comprising a 265H substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 265K substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 265S substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 265Y substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 267G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 267H substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 267I substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 267K substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 268K substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 269N substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 269Q substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 270A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 270G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 270M substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 270N substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 271T substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 272N substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 279F substitution according to the Kabat numbering system.In some embodiments, the antibody comprises an IgG1 Fc region comprising a 279K substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 279L substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 292E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 292F substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 292G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 292I substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 293S substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 301W substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 304E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 311E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 311G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 311S substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 316F substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 327T substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 328V substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 329Y substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 330R substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 339E substitution according to the Kabat numbering system.In some embodiments, the antibody comprises an IgG1 Fc region comprising a 339L substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 343I substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 343V substitution according to the Kabat numbering system. In some embodiments, the antibody comprises a 373A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 373G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 373S substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 376E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 376W substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 376Y substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 380D substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 382D substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 382P substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 385P substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 424H substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 424M substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 424V substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 434I substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 438G substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 439E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 439H substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 439Q substitution according to the Kabat numbering system.In some embodiments, the antibody comprises an IgG1 Fc region comprising a 440A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 440D substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 440E substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 440F substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 440M substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 440T Fc region substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising a 440V substitution according to the Kabat numbering system.

[0162] In some embodiments, the antibody comprises an Fc region selected from the representative sequences disclosed in Table 3. In some embodiments, the antibody comprises an IgG1 Fc region comprising E233P according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG4 Fc region comprising S228P and L235E. In some embodiments, the antibody comprises an IgG1 Fc region comprising L235E according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising L234A and L235A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising L234A, L235A, and G237A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising L234A, L235A, and P329G according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising L234F, L235E, and P331S according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising L234A, L235E, and G237A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising L234A, L235E, G237A, and P331S according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ) according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising L234A, L235A, and P329A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising G236R and L328R according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising G237A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising F241A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising V264A according to the Kabat numbering system.In some embodiments, the antibody comprises an IgG1 Fc region that comprises D265A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region that comprises D265A and N297A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region that comprises D265A and N297G according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region that comprises D270A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region that comprises N297A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region that comprises N297G according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region that comprises N297D according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region that comprises N297Q according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising P329A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising P329G according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising P329R according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising A330L according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising P331A according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG1 Fc region comprising P331S according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG2 Fc region. In some embodiments, the antibody comprises an IgG4 Fc region. In some embodiments, the antibody comprises an IgG4 Fc region comprising S228P according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG4 Fc region comprising S228P, F234A, and L235A according to the Kabat numbering system, hi some embodiments, the antibody comprises an IgG2-IgG4 cross-subclass (IgG2 / G4) Fc region.In some embodiments, the antibody comprises an IgG2-IgG3 cross-subclass Fc region. In some embodiments, the antibody comprises an IgG2 Fc region comprising H268Q, V309L, A330S, and P331S according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG2 Fc region comprising V234A, G237A, P238S, H268A, V309L, A330S, and P331S according to the Kabat numbering system. In some embodiments, the antibody comprises an Fc region comprising high mannose glycosylation.

[0163] In some embodiments, the antibody comprises an IgG4 Fc region comprising an S228P substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG4 Fc region comprising an A330S substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG4 Fc region comprising a P331S substitution according to the Kabat numbering system.

[0164] In some embodiments, the antibody comprises an IgG2 Fc region comprising an A330S substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG2 Fc region comprising a P331S substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG2 Fc region comprising a 234A substitution according to the Kabat numbering system. In some embodiments, the antibody comprises an IgG2 Fc region comprising a 237A substitution according to the Kabat numbering system.

[0165] In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising a sequence in Table 9B. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region shown in Table 14.

[0166] [Table 1]

[0167] In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 320, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 320. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 321, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 321. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 322, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 322. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 323, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 323. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 324, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 324. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 325, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 325. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 326, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 326. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 327, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 327.In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 328, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 328. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 329, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 329. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 330, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 330. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 331, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 331. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 332, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 332. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 333, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 333. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 334, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 334. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 335, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 335.In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 336, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 336. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 337, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 337. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 338, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 338. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 339, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 339. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 340, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 340. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 341, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 341. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 342, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 342. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 343, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 343.In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 344, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 344. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 345, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 345. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 346, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 346. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 347, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 347. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 348, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 348. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 349, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 349. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 350, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 350. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 351, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 351.In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 352, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 352. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 353, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 353. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 354, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 354. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 355, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 355. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 356, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 356. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 357, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 357. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 358, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 358. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 359, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 359.In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 360, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 360. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 361, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 361. In certain embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 362, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 362.

[0168] In some embodiments, the antibodies of the present disclosure are variants that retain some but not all effector functions, making them desirable candidates for applications where the in vivo half-life of the antibody is important but certain effector functions (e.g., complement and ADCC) are unnecessary or deleterious.

[0169] In vitro and / or in vivo cytotoxicity assays can be performed to confirm the reduction / depletion of CDC and / or ADCC activity. For example, Fc receptor (FcR) binding assays can be performed to ensure that the antibody lacks FcγR binding (and therefore likely lacks ADCC activity) but retains FcRn binding ability. Measurement of effector function can be performed as described in Example 3.

[0170] In some embodiments, antibodies are tested for binding to Fcγ receptors and complement C1q by ELISA. In some embodiments, antibodies are tested for their ability to activate human primary immune cells in vitro, for example, by assessing their ability to induce expression of activation markers.

[0171] In some embodiments, assessing the ADCC activity of anti-TL1A antibodies involves adding the antibodies to target cells in combination with immune effector cells, which can be activated by the antigen-antibody complex to cause cytolysis of the target cells. Cytolysis can be detected by the release of a label (e.g., a radioactive substrate, a fluorescent dye, or a naturally occurring intracellular protein) from the lysed cells. Useful effector cells for such assays include peripheral blood mononuclear cells (PBMCs) and natural killer (NK) cells. Specific examples of in vitro ADCC assays are described in Wisecarver et al., 1985, 79:277-282; Bruggemann et al., 1987, J Exp Med 166:1351-1361; Wilkinson et al., 2001, J Immunol Methods 258:183-191; Patel et al., 1995, J Immunol Methods 184:29-38. Alternatively, or additionally, ADCC activity of the antibody of interest may be assessed in vivo, e.g., in an animal model such as that disclosed in Clynes et al., 1998, PNAS USA 95:652-656.

[0172] In some embodiments, antibodies comprising the Fc region herein exhibit reduced ADCC activity compared to an unmodified antibody (e.g., an antibody based on human IgG1). In some embodiments, the antibodies herein exhibit ADCC activity that is at least 2-fold, 3-fold, 5-fold, 10-fold, 50-fold, or 100-fold less than that of an unmodified antibody. In some embodiments, the antibodies herein exhibit ADCC activity that is reduced by at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 100%, at least 200%, at least 300%, at least 400%, or at least 500% compared to an unmodified antibody. In certain embodiments, the antibodies herein have no detectable ADCC activity. In certain embodiments, the reduced and / or diminished ADCC activity may be due to a reduced affinity of the antibodies of the invention for Fc ligands and / or receptors.

[0173] In some embodiments, a CDC assay, an assessment of complement activation, may be performed as described in Gazzano-Santoro et al., 1996, J. Immunol. Methods, 202:163.

[0174] In some embodiments, antibodies comprising an Fc region described herein exhibit reduced affinity for C1q compared to an unmodified antibody (e.g., human IgG1). In some embodiments, the antibodies herein exhibit affinity for the C1q receptor that is at least 2-fold, or at least 3-fold, or at least 5-fold, or at least 7-fold, or at least 10-fold, or at least 20-fold, or at least 30-fold, or at least 40-fold, or at least 50-fold, or at least 60-fold, or at least 70-fold, or at least 80-fold, or at least 90-fold, or at least 100-fold, or at least 200-fold less than the unmodified antibody. In some embodiments, the antibodies herein exhibit affinity for C1q that is at least 90%, at least 80%, at least 70%, at least 60%, at least 50%, at least 40%, at least 30%, at least 20%, at least 10%, or at least 5% less than the unmodified antibody. In some embodiments, the antibodies herein exhibit an affinity for C1q of about 100 nM to about 100 μM, or about 100 nM to about 10 μM, or about 100 nM to about 1 μM, or about 1 nM to about 100 μM, or about 10 nM to about 100 μM, or about 1 μM to about 100 μM, or about 10 μM to about 100 μM. In certain embodiments, the antibodies herein exhibit an affinity for C1q of greater than 1 μM, greater than 5 μM, greater than 10 μM, greater than 25 μM, greater than 50 μM, or greater than 100 μM.

[0175] In some embodiments, antibodies comprising an Fc region described herein exhibit reduced CDC activity compared to an unmodified antibody (e.g., human IgG1). In some embodiments, the antibodies herein exhibit ADCC activity that is at least 2-fold, or at least 3-fold, or at least 5-fold, or at least 10-fold, or at least 50-fold, or at least 100-fold less than the CDC activity of an unmodified antibody. In some embodiments, the antibodies herein exhibit CDC activity that is reduced by at least 10%, or at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 100%, or at least 200%, at least 300%, or at least 400%, or at least 500% compared to an unmodified antibody. In certain embodiments, the antibodies herein exhibit no detectable CDC activity. In some embodiments, the reduced and / or diminished CDC activity may be due to a reduced affinity of the antibodies of the invention for Fc ligands and / or receptors.

[0176] Thus, further provided and described herein are anti-TL1A antibodies comprising a variant (e.g., having a mutation) Fc region that reduces a cytotoxic response (e.g., ADCC or CDC) elicited by the anti-TL1A antibody. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 401, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 401. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 402, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 402. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 403, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 403. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 404, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 404. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 405, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 405. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 406, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 406. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 407, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 407.In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 408, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 408. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 409, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 409. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 410, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 410. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 411, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 411. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 412, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 412. In some embodiments, the anti-TL1A antibodies described herein comprise an Fc region comprising SEQ ID NO: 413, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 413.

[0177] As a further example, in certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 501, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 501. In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 502, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 502. In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 503, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 503. In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 504, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 504. In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 505, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 505. In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 506, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 506. In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 507, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 507. In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 508, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 508.In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 509, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 509. In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 510, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 510. In certain embodiments, the anti-TL1A antibodies described herein comprise a heavy chain comprising SEQ ID NO: 511, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 511. In certain embodiments, an anti-TL1A antibody described herein comprises a heavy chain comprising SEQ ID NO: 512, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 512. In certain embodiments, an anti-TL1A antibody described herein comprises a heavy chain comprising SEQ ID NO: 513, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 513. In certain embodiments, the heavy chain is paired with a light chain comprising SEQ ID NO: 514, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 514. In certain embodiments, the heavy chain is paired with the light chain variable region of SEQ ID NO:514, or a sequence that is at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to the light chain variable region of SEQ ID NO:514.

[0178] In some embodiments, the anti-TL1A described herein comprises a light chain constant region comprising SEQ ID NO: 319, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to SEQ ID NO: 319.

[0179] Further Non-Limiting Exemplary Anti-TL1A Antibodies In one aspect, provided herein is a first embodiment of an anti-TL1A antibody comprising a heavy chain comprising HCDR1, HCDR2, and HCDR3, and a light chain comprising LCDR1, LCDR2, and LCDR3. Non-limiting further embodiments include: (Embodiment 2) the anti-TL1A antibody of Embodiment 1, comprising an HCDR1 comprising SEQ ID NO: 1. (Embodiment 3) the anti-TL1A antibody of Embodiment 1 or Embodiment 2, comprising an HCDR2 comprising SEQ ID NO: 2. (Embodiment 4) the anti-TL1A antibody of Embodiment 1 or Embodiment 2, comprising an HCDR2 comprising SEQ ID NO: 3. (Embodiment 5) the anti-TL1A antibody of Embodiment 1 or Embodiment 2, comprising an HCDR2 comprising SEQ ID NO: 4. (Embodiment 6) the anti-TL1A antibody of Embodiment 1 or Embodiment 2, comprising an HCDR2 comprising SEQ ID NO: 5. (Embodiment 7) the anti-TL1A antibody of any one of Embodiments 1 to 6, comprising an HCDR3 comprising SEQ ID NO: 6. (Embodiment 8) the anti-TL1A antibody of any one of Embodiments 1 to 6, comprising an HCDR3 comprising SEQ ID NO: 7. (Embodiment 9) The anti-TL1A antibody of any one of Embodiments 1 to 6, comprising an HCDR3 comprising SEQ ID NO: 8. (Embodiment 10) The anti-TL1A antibody of any one of Embodiments 1 to 6, comprising an HCDR3 comprising SEQ ID NO: 9. (Embodiment 11) The anti-TL1A antibody of any one of Embodiments 1 to 10, comprising an LCDR1 comprising SEQ ID NO: 10. (Embodiment 12) The anti-TL1A antibody of any one of Embodiments 1 to 11, comprising an LCDR2 comprising SEQ ID NO: 11. (Embodiment 13) The anti-TL1A antibody of any one of Embodiments 1 to 12, comprising an LCDR3 comprising SEQ ID NO: 12. (Embodiment 14) The anti-TL1A antibody of any one of Embodiments 1 to 12, comprising an LCDR3 comprising SEQ ID NO: 13. (Embodiment 15) The anti-TL1A antibody of any one of Embodiments 1 to 12, comprising an LCDR3 comprising SEQ ID NO: 14 or 15.

[0180] (Embodiment 16) IGHV1-46 * 02. (Embodiment 17) The anti-TL1A antibody of any one of embodiments 1 to 15, comprising a heavy chain framework comprising: SEQ ID NO: 316. (Embodiment 17) IGHV1-46 comprising about 1 to about 20 amino acid substitutions from SEQ ID NO: 316. *16. The anti-TL1A antibody of any one of embodiments 1 to 15, comprising a heavy chain framework comprising a variant of SEQ ID NO: 02. (Embodiment 18) IGHV1-46 comprising about 1 to about 9 amino acid substitutions from SEQ ID NO: 316. * 02. (Embodiment 19) The anti-TL1A antibody of any one of embodiments 1 to 15, comprising a heavy chain framework comprising a variant of SEQ ID NO: 316. (Embodiment 19) An IGHV1-46 antibody comprising about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid substitutions within the framework from SEQ ID NO: 316. * 02 variant. (Embodiment 20) The anti-TL1A antibody of any one of embodiments 1 to 19, wherein the heavy chain framework substitution comprises Q1E as determined by Kabat numbering. (Embodiment 21) The anti-TL1A antibody of any one of embodiments 17 to 20, wherein the heavy chain framework substitution comprises R45K as determined by Kabat numbering. (Embodiment 22) The anti-TL1A antibody of any one of embodiments 17 to 21, wherein the heavy chain framework substitution comprises A47R as determined by Kabat numbering. (Embodiment 23) The anti-TL1A antibody of any one of embodiments 17 to 22, wherein the heavy chain framework substitution comprises M55I as determined by Kabat numbering. (Embodiment 24) The anti-TL1A antibody of any one of embodiments 17 to 23, wherein the heavy chain framework substitution comprises V78A as determined by Kabat numbering. (Embodiment 25) The anti-TL1A antibody of any one of embodiments 17 to 24, wherein the heavy chain framework substitution comprises M80I as determined by Kabat numbering. (Embodiment 26) The anti-TL1A antibody of any one of embodiments 17 to 25, wherein the heavy chain framework substitution comprises R82T as determined by Kabat numbering. (Embodiment 27) The anti-TL1A antibody of any one of embodiments 17 to 26, wherein the heavy chain framework substitution comprises V89A as determined by Kabat numbering. (Embodiment 28) The anti-TL1A antibody of any one of embodiments 17 to 27, wherein the heavy chain framework substitution comprises M91L as determined by Kabat numbering.

[0181] (Embodiment 29) The anti-TL1A antibody of any one of embodiments 1 to 15, comprising a heavy chain framework comprising SEQ ID NO: 301. (Embodiment 30) The anti-TL1A antibody of embodiment 29, wherein X1 is Q. (Embodiment 31) The anti-TL1A antibody of embodiment 29, wherein X1 = E. (Embodiment 32) The anti-TL1A antibody of any one of embodiments 29 to 31, wherein X2 = R. (Embodiment 33) The anti-TL1A antibody of any one of embodiments 29 to 31, wherein X2 = K. (Embodiment 34) The anti-TL1A antibody of any one of embodiments 29 to 33, wherein X3 = A. (Embodiment 35) The anti-TL1A antibody of any one of embodiments 29 to 33, wherein X3 = R. (Embodiment 36) The anti-TL1A antibody of any one of embodiments 29 to 35, wherein X4 = M. (Embodiment 37) The anti-TL1A antibody of any one of embodiments 29 to 35, wherein X4 = I. (Embodiment 38) The anti-TL1A antibody of any one of embodiments 29 to 37, wherein X5 = V. (Embodiment 39) Anti-TL1A of any one of embodiments 29 to 37, wherein X5 = A. (Embodiment 40) Anti-TL1A of any one of embodiments 29 to 39, wherein X6 = M. (Embodiment 41) Anti-TL1A of any one of embodiments 29 to 39, wherein X6 = I. (Embodiment 42) Anti-TL1A of any one of embodiments 29 to 41, wherein X7 = R. (Embodiment 43) Anti-TL1A of any one of embodiments 29 to 41, wherein X7 = T. (Embodiment 44) Anti-TL1A of any one of embodiments 29 to 43, wherein X8 = V. (Embodiment 45) Anti-TL1A of any one of embodiments 29 to 43, wherein X8 = A. (Embodiment 46) Anti-TL1A of any one of embodiments 29 to 45, wherein X9 = M. (Embodiment 47) Anti-TL1A of any one of embodiments 29 to 45, wherein X9 = L.

[0182] (Embodiment 48) The anti-TL1A antibody of any one of embodiments 1 to 15, comprising a heavy chain framework comprising SEQ ID NO: 302. (Embodiment 49) The anti-TL1A antibody of embodiment 48, in which X1 is Q. (Embodiment 50) The anti-TL1A antibody of embodiment 48, in which X1 = E. (Embodiment 51) The anti-TL1A antibody of any one of embodiments 48 to 50, in which X2 = R. (Embodiment 52) ​​The anti-TL1A antibody of any one of embodiments 48 to 50, in which X2 = K. (Embodiment 53) The anti-TL1A antibody of any one of embodiments 48 to 52, in which X3 = A. (Embodiment 54) The anti-TL1A antibody of any one of embodiments 48 to 52, in which X3 = R. (Embodiment 55) The anti-TL1A antibody of any one of embodiments 48 to 54, in which X4 = M. (Embodiment 56) The anti-TL1A antibody of any one of embodiments 48 to 54, in which X4 = I. (Embodiment 57) The anti-TL1A antibody of any one of embodiments 48 to 56, in which X5 = V. (Embodiment 58) An anti-TL1A according to any one of embodiments 48 to 56, in which X5 = A. (Embodiment 59) An anti-TL1A according to any one of embodiments 48 to 58, in which X6 = M. (Embodiment 60) An anti-TL1A according to any one of embodiments 48 to 58, in which X6 = I. (Embodiment 61) An anti-TL1A according to any one of embodiments 48 to 60, in which X7 = R. (Embodiment 62) An anti-TL1A according to any one of embodiments 48 to 60, in which X7 = T. (Embodiment 63) An anti-TL1A according to any one of embodiments 48 to 62, in which X8 = V. (Embodiment 64) An anti-TL1A according to any one of embodiments 48 to 62, in which X8 = A. (Embodiment 65) An anti-TL1A according to any one of embodiments 48 to 64, in which X9 = M. (Embodiment 66) An anti-TL1A according to any one of embodiments 48 to 64, in which X9 = L.

[0183] (Embodiment 67) IGKV3-20 * 01. (Embodiment 68) The anti-TL1A antibody of any one of embodiments 1 to 66, comprising a light chain framework comprising: IGKV3-20; * 67. The anti-TL1A antibody of any one of embodiments 1 to 66, comprising a light chain framework comprising a variant of SEQ ID NO: 01. 68. The anti-TL1A antibody of any one of embodiments 1 to 66, comprising an IGKV3-20 light chain framework comprising about one amino acid substitution from SEQ ID NO: 317.* 67. The anti-TL1A antibody of any one of embodiments 1 to 66, comprising a light chain framework comprising a variant of SEQ ID NO: 01. (Embodiment 70) IGKV3-20 comprising about two amino acid substitutions from SEQ ID NO: 317 * 71. The anti-TL1A antibody of any one of embodiments 1 to 66, comprising a light chain framework comprising a variant of SEQ ID NO: 317. 72. The anti-TL1A antibody of any one of embodiments 1 to 66, comprising an IGKV3-20 light chain framework comprising about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid substitutions from SEQ ID NO: 317 within the framework. * 01. (Embodiment 72) The anti-TL1A antibody of any one of embodiments 69 to 71, wherein the light chain framework substitution comprises Q1E as determined by Kabat numbering. (Embodiment 73) The anti-TL1A antibody of any one of embodiments 69 to 72, wherein the light chain framework substitution comprises R45K as determined by Kabat numbering.

[0184] (Embodiment 74) The anti-TL1A antibody of any one of embodiments 1 to 66, comprising a light chain comprising a light chain framework comprising SEQ ID NO: 303. (Embodiment 75) The anti-TL1A antibody of embodiment 74, wherein X10 is L. (Embodiment 76) The anti-TL1A antibody of embodiment 74, wherein X10 is P. (Embodiment 77) The anti-TL1A antibody of any one of embodiments 74 to 76, wherein X11 is L. (Embodiment 78) The anti-TL1A antibody of any one of embodiments 74 to 76, wherein X11 is W.

[0185] (Embodiment 79) According to the Kabat numbering, (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A , 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G, (yy) L234F, L235E, and P331S, (zz) L234A, L235E, and G237A,(aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (eee) G237A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of (a)-(uu). (Embodiment 80) The anti-TL1A of any one of embodiments 1-78, comprising (i) a human IgG4 Fc region or (ii) a human IgG4 Fc region comprising: (a) S228P and L235E, or (b) S228P, F234A, and L235A according to the Kabat numbering. (Embodiment 81) The anti-TL1A antibody of any one of embodiments 1 to 78, comprising a human IgG2 Fc region; an IgG2-IgG4 cross-subclass Fc region; an IgG2-IgG3 cross-subclass Fc region; an IgG2 comprising H268Q, V309L, A330S, P331S (IgG2m4); or an IgG2 comprising V234A, G237A, P238S, H268A, V309L, A330S, P331S (IgG2σ). (Embodiment 82) The anti-TL1A antibody of any one of embodiments 1 to 81, comprising a heavy chain Fc region comprising any one of SEQ ID NOs: 320 to 362. (Embodiment 83) The anti-TL1A antibody of any one of embodiments 1 to 82, comprising a light chain constant region comprising SEQ ID NO: 319.

[0186] (Embodiment 84) The anti-TL1A antibody of any one of embodiments 1 to 83, comprising a monomer fraction of at least about 80%, as determined by the size exclusion chromatography method described herein. (Embodiment 85) The anti-TL1A antibody of any one of embodiments 1 to 84, comprising a monomer fraction of at least about 81%, at least about 82%, at least about 83%, or at least about 84%, as determined by the size exclusion chromatography method described herein. (Embodiment 86) The anti-TL1A antibody of any one of embodiments 1 to 85, comprising a monomer fraction of at least about 85%, as determined by the size exclusion chromatography method described herein. (Embodiment 87) The anti-TL1A antibody of any one of embodiments 1 to 86, comprising a monomer fraction of at least about 86%, at least about 87%, at least about 88%, or at least about 89%, as determined by the size exclusion chromatography method described herein. (Embodiment 88) The anti-TL1A antibody of any one of embodiments 1 to 87, comprising a monomer fraction of at least about 90%, as determined by the size exclusion chromatography method described herein. (Embodiment 89) The anti-TL1A antibody of any one of embodiments 1 to 88, comprising a monomer fraction of at least about 91%, at least about 92%, at least about 93%, or at least about 94%, as determined by the size exclusion chromatography method described herein. (Embodiment 90) The anti-TL1A antibody of any one of embodiments 1 to 89, comprising a monomer fraction of at least about 95%, as determined by the size exclusion chromatography method described herein. (Embodiment 91) The anti-TL1A antibody of any one of embodiments 1 to 90, comprising a monomer fraction of at least about 96%, at least about 97%, at least about 98%, or at least about 99%, as determined by the size exclusion chromatography method described herein.

[0187] (Embodiment 92) The anti-TL1A antibody of any one of embodiments 1 to 91, comprising an expression of at least about 2 μg / mL, as determined by the methods disclosed herein. (Embodiment 93) The anti-TL1A antibody of any one of embodiments 1 to 92, comprising an expression of about 2 μg / mL to about 60 μg / mL, as determined by the methods disclosed herein. (Embodiment 94) The anti-TL1A antibody of any one of embodiments 1 to 93, comprising an expression of about 5 μg / mL to about 60 μg / mL, as determined by the methods disclosed herein. (Embodiment 95) The anti-TL1A antibody of any one of embodiments 1 to 94, comprising an expression of about 10 μg / mL to about 60 μg / mL, as determined by the methods disclosed herein. (Embodiment 96) The anti-TL1A antibody of any one of embodiments 1 to 95, comprising an expression of at least about 5 μg / mL, as determined by the methods disclosed herein. (Embodiment 97) The anti-TL1A antibody of any one of embodiments 1 to 96, comprising an expression of at least about 10 μg / mL, as determined by the methods disclosed herein. (Embodiment 98) The anti-TL1A antibody of any one of embodiments 1 to 97, comprising an expression of at least about 15 μg / mL, as determined by the methods disclosed herein. (Embodiment 99) The anti-TL1A antibody of any one of embodiments 1 to 98, comprising an expression of at least about 20 μg / mL, as determined by the methods disclosed herein. (Embodiment 100) The anti-TL1A antibody of any one of embodiments 1 to 91, comprising an expression of about 2 μg / mL to about 50 μg / mL, about 2 μg / mL to about 40 μg / mL, about 2 μg / mL to about 30 μg / mL, about 2 μg / mL to about 20 μg / mL, about 5 μg / mL to about 50 μg / mL, about 5 μg / mL to about 40 μg / mL, about 5 μg / mL to about 30 μg / mL, about 10 μg / mL to about 50 μg / mL, about 10 μg / mL to about 40 μg / mL, or about 10 μg / mL to about 30 μg / mL, as determined by the methods disclosed herein. (Embodiment 101) An anti-TL1A antibody of any one of embodiments 1 to 91, comprising an expression of about 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 μg / mL as determined by the methods disclosed herein.

[0188] In some embodiments, the anti-TL1A antibody comprises antibody A. As used herein, antibody A comprises the CDRs of antibody A in Table 10. In some cases, antibody A comprises a heavy chain framework comprising SEQ ID NO: 301 (embodiment X1VQLVQSGAEVKKPGASVKVSCKAS[HCDR1]WVX2QX3PGQGLEWX4G[HCDR2]RX5TX6TX7DTSTSTX8YX9ELSSLRSEDTAVYYCAR[HCDR3]WGQGTTVTVSS), where X1 = Q or E, X2 = R or K, X3 = A or R, X4 = M or I, X5 = V or A, X6 = M or I, X7 = R or T, X8 = V or A, and X9 = M or L. In some instances, antibody A comprises a light chain framework comprising SEQ ID NO: 303 (embodiment EIVLTQSPGTLSLSPGERATLSC[LCDR1]WYQQKPGQAPRX10X11IY[LCDR2]GIPDRFSGSGSGTDFTLTISRLEPEDFAVYYC[LCDR3]FGGGTKLEIK), where X10=L or P, X11=L or W. In some instances, antibody A comprises a light chain framework comprising a human IGHV1-46 * 02 framework or modified human IGHV1-46 * a heavy chain variable region comprising a modified human IGHV1-46 *The 02 framework has about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or fewer amino acid substitutions within the framework. In some cases, antibody A comprises a light chain variable region comprising a human IGKV3-20 framework or a modified human IGKV3-20 framework, wherein the modified human IGKV3-20 framework has about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or fewer amino acid substitutions within the framework. In some cases, antibody A comprises a constant region with reduced ADCC and / or CDC compared to IgG1. For example, antibody A may be (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, according to the Kabat numbering system. ) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270G, 270M, or 270N, (x ) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S,(kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 44 0M, 440T, or 440V, (tt)E233P, (uu)L235E, (vv)L234A and L235A, (ww)L234A, L235A, and G237A, (xx)L234A, L235A, and P329G, (yy)L234F, L235E, and P331S, (zz)L234A, L235E, and and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (eee) G2 In some cases, antibody A comprises a human IgG1 Fc region comprising the following constant regions: (a) N297A, (b) V264A, (c) D265A, (d) F241A, (e) V264A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of (a)-(uu). In some cases, antibody A comprises a human IgG1 Fc region comprising the following constant regions: (a) N297A, (fff) F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of (a)-(uu). In some cases, antibody A comprises a human IgG1 Fc region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 320. In some instances, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 321. In some instances, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 322. In some instances, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 323.97%, 98%, 99%, or 100% identity to SEQ ID NO: 324. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 324. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 325. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 326. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 327. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 328. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 329. In some instances, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 330. In some instances, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 331. In some instances, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 332.or 100% identity to SEQ ID NO: 333. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 333. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 334. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 335. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 336. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 337. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 338. In some instances, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 339. In some instances, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 340. In some instances, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 341.or 100% identity to SEQ ID NO: 342. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 342. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 343. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 344. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 345. In some cases, antibody A comprises a constant region that comprises at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 346. In some cases, antibody A comprises a constant region that comprises at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 347. , 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 348. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 348. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 349. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 350. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 351. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 352. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 353. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 354. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 355.In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 356. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 357. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 358. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 359. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 360. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 361. In some cases, antibody A comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 362. In some cases, antibody A comprises a monomer fraction of at least about 80%, 81%, 82%, 83%, 84%, 85%, 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% as measured by size exclusion methods described in Example 2.In some cases, ANTIBODY A is expressed from FreeStyle 293-F (e.g., ThermoFisher Scientific #R79007) cells at an expression level of about, or at least about, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 5, 57, 58, 59, or 60 μg / mL as determined by the method described in Example 2. In some cases, antibody A is expressed from FreeStyle 293-F cells at an expression level of about 2 μg / mL to about 60 μg / mL. In some cases, antibody A is expressed from FreeStyle 293-F cells at an expression level of about 10 μg / mL to about 60 μg / mL. In some cases, antibody A comprises a viscosity of less than about 30 mPa-s. In some cases, antibody A comprises a viscosity of about 4 mPa-s to about 30 mPa-s, or about 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 mPa-s. In some cases, antibody A is formulated as a solution having a concentration of about 10 mg / mL to about 170 mg / mL and a viscosity of less than about 30 mPa-s. In some cases, the formulation has a pH of about 5 to about 7.5.

[0189] In some embodiments, the anti-TL1A antibody comprises antibody B. As used herein, antibody B comprises the CDRs of antibody B in Table 10. In some cases, antibody B comprises a heavy chain framework comprising SEQ ID NO: 301 (X1VQLVQSGAEVKKPGASVKVSCKAS[HCDR1]WVX2QX3PGQGLEWX4G[HCDR2]RX5TX6TX7DTSTSTX8YX9ELSSLRSEDTAVYYCAR[HCDR3]WGQGTTVTVSS), where X1 = Q or E, X2 = R or K, X3 = A or R, X4 = M or I, X5 = V or A, X6 = M or I, X7 = R or T, X8 = V or A, and X9 = M or L. In some instances, antibody B comprises a light chain framework comprising SEQ ID NO: 303 (EIVLTQSPGTLSLSPGERATLSC[LCDR1]WYQQKPGQAPRX10X11IY[LCDR2]GIPDRFSGSGSGTDFTLTISRLEPEDFAVYYC[LCDR3]FGGGTKLEIK), where X10 = L or P, X11 = L or W. In some instances, antibody B comprises a light chain framework comprising a light chain comprising SEQ ID NO: 303 (EIVLTQSPGTLSLSPGERATLSC[LCDR1]WYQQKPGQAPRX10X11IY[LCDR2]GIPDRFSGSGSGTDFTLTISRLEPEDFAVYYC[LCDR3]FGGGTKLEIK), where X10 = L or P, X11 = L or W. * 02 framework or modified human IGHV1-46 * a heavy chain variable region comprising a modified human IGHV1-46 *The 02 framework has about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or fewer amino acid substitutions within the framework. In some cases, antibody B comprises a light chain variable region comprising a human IGKV3-20 framework or a modified human IGKV3-20 framework, wherein the modified human IGKV3-20 framework has about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or fewer amino acid substitutions within the framework. In some cases, antibody B comprises a constant region with reduced ADCC and / or CDC compared to IgG1. For example, antibody B may be (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, according to the Kabat numbering system. ) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270G, 270M, or 270N, (x ) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S,(kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 44 0M, 440T, or 440V, (tt)E233P, (uu)L235E, (vv)L234A and L235A, (ww)L234A, L235A, and G237A, (xx)L234A, L235A, and P329G, (yy)L234F, L235E, and P331S, (zz)L234A, L235E, and and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (eee) G2 37A, (fff)F241A, (ggg)V264A, (hhh)D265A, (iii)D265A and N297A, (jjj)D265A and N297G, (kkk)D270A, (lll)A330L, (mmm)P331A or P331S, or (nnn) any combination of (a)-(uu). Optionally, antibody B comprises a human IgG1 Fc region comprising a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 320. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 321. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 322. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 323.97%, 98%, 99%, or 100% identity to SEQ ID NO: 324. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 324. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 325. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 326. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 327. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 328. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 329. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 330. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 331. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 332.or 100% identity to SEQ ID NO: 333. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 333. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 334. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 335. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 336. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 337. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 338. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 339. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 340. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 341.or 100% identity to SEQ ID NO: 342. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 342. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 343. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 344. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 345. In some cases, antibody B comprises a constant region that comprises at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 346. In some cases, antibody B comprises a constant region that comprises at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 347. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 348. In some instances, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 349. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 350. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 351. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 352. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 353. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 354. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 355.In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 356. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 357. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 358. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 359. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 360. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 361. In some cases, antibody B comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 362. In some cases, antibody B comprises a monomer fraction of at least about 80%, 81%, 82%, 83%, 84%, 85%, 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% as measured by size exclusion methods described in Example 2.In some cases, antibody B is expressed from FreeStyle 293-F cells at an expression level of about, or at least about, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 5, 57, 58, 59, or 60 μg / mL, as determined by the method described in Example 2. In some cases, antibody B is expressed from FreeStyle 293-F cells at an expression level of about 2 μg / mL to about 60 μg / mL. Optionally, antibody B is expressed from FreeStyle 293-F cells at an expression level of about 10 μg / mL to about 60 μg / mL.

[0190] In some embodiments, the anti-TL1A antibody comprises antibody C. As used herein, antibody C comprises the CDRs of antibody C in Table 10. In some cases, antibody C comprises a heavy chain framework comprising SEQ ID NO: 301 (X1VQLVQSGAEVKKPGASVKVSCKAS[HCDR1]WVX2QX3PGQGLEWX4G[HCDR2]RX5TX6TX7DTSTSTX8YX9ELSSLRSEDTAVYYCAR[HCDR3]WGQGTTVTVSS), where X1 = Q or E, X2 = R or K, X3 = A or R, X4 = M or I, X5 = V or A, X6 = M or I, X7 = R or T, X8 = V or A, and X9 = M or L. In some instances, antibody C comprises a light chain framework comprising SEQ ID NO: 303 (EIVLTQSPGTLSLSPGERATLSC[LCDR1]WYQQKPGQAPRX10X11IY[LCDR2]GIPDRFSGSGSGTDFTLTISRLEPEDFAVYYC[LCDR3]FGGGTKLEIK), where X10 = L or P, X11 = L or W. In some instances, antibody C comprises a light chain framework comprising a light chain comprising SEQ ID NO: 303 (EIVLTQSPGTLSLSPGERATLSC[LCDR1]WYQQKPGQAPRX10X11IY[LCDR2]GIPDRFSGSGSGTDFTLTISRLEPEDFAVYYC[LCDR3]FGGGTKLEIK), where X10 = L or P, X11 = L or W. * 02 framework or modified human IGHV1-46 * a heavy chain variable region comprising a modified human IGHV1-46 *The 02 framework has about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or fewer amino acid substitutions within the framework. In some cases, antibody C comprises a light chain variable region comprising a human IGKV3-20 framework or a modified human IGKV3-20 framework, wherein the modified human IGKV3-20 framework has about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 or fewer amino acid substitutions within the framework. In some cases, antibody C comprises a constant region with reduced ADCC and / or CDC compared to IgG1. For example, antibody C may be (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, according to the Kabat numbering system. ) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270G, 270M, or 270N, (x ) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S,(kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 44 0M, 440T, or 440V, (tt)E233P, (uu)L235E, (vv)L234A and L235A, (ww)L234A, L235A, and G237A, (xx)L234A, L235A, and P329G, (yy)L234F, L235E, and P331S, (zz)L234A, L235E, and and G237A, (aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (eee) G2 In some embodiments, antibody C comprises a human IgG1 Fc region comprising the following constant regions: (a) 37A, (b) 37A, (c) 37B, (d) 37C, (e) 37D, (f) 37E, (f) 37F, (g) 37G, (h) 37H, (i) 37H, (j) 37H and N297A, (j) 37H and N297G, (k) 37G, (k) 37H, (l) 37H, (m) 37H and N297A, (j) 37H and N297G, (k) 37H, (k) 37H, (l) 37H, (m) 37H and N297A, (j) 37H and N297G, (k) 37H, (k) 37H, (f) 37H, (f) 37H, (f) 37H, (g) 37H, (h) 37H, (h) 37H, (i) 37H and N297A, (j) 37H and N297G, (k) 37H, (k) 37H, (f ... In some instances, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 321. In some instances, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 322. In some instances, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 323.97%, 98%, 99%, or 100% identity to SEQ ID NO: 324. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 324. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 325. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 326. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 327. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 328. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 329. In some instances, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 330. In some instances, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 331. In some instances, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 332.or 100% identity to SEQ ID NO: 333. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 333. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 334. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 335. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 336. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 337. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 338. In some instances, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 339. In some instances, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 340. In some instances, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 341.or 100% identity to SEQ ID NO: 342. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity to SEQ ID NO: 342. In some cases, antibody C comprises a constant region comprising at least about 85%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, o...

Claims

1. An antibody or antigen-binding fragment thereof that binds to TL1A, comprising: ＊ 02 framework or modified human IGHV1-46 ＊ a heavy chain variable framework region comprising a human IGKV3-20 framework or a modified human IGKV3-20 framework, and a light chain variable framework region comprising a human IGKV3-20 framework or a modified human IGKV3-20 framework; said heavy chain variable framework region and said light chain variable framework region collectively comprising said human IGHV1-46 ＊ 02 framework and less than 9 amino acid modifications from the human IGKV3-20 framework, or an antigen-binding fragment thereof.

2. (c) an alteration at amino acid position 55 in the heavy chain variable region; (d) an alteration at amino acid position 78 in the heavy chain variable region; (e) an alteration at amino acid position 80 in the heavy chain variable region; (f) an alteration at amino acid position 82 in the heavy chain variable region; (g) an alteration at amino acid position 89 in the heavy chain variable region; or (h) an alteration at amino acid position 91 in the heavy chain variable region; or a combination of two or more alterations selected from (a) to (h).

3. (a) the amino acid modification is at position 47 in the heavy chain variable region and the amino acid at position 47 is R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V; (b) the amino acid modification is at position 45 in the heavy chain variable region and the amino acid at position 45 is A, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V; (c) the amino acid modification is (d) the amino acid modification is at position 78 in the heavy chain variable region and the amino acid at position 78 is A, R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, Y, or V; (e) the amino acid modification is at position 80 in the heavy chain variable region and the amino acid at position 80 is A, R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, or Y; (f) the amino acid modification is at position 82 in the heavy chain variable region and the amino acid at position 82 is A, N, D, C, Q, E, G, H, I, L, K, F, P, S, T, W, Y, or V; (g) the amino acid modification is at position 89 in the heavy chain variable region and the amino acid at position 89 is A, 3. The antibody or antigen-binding fragment of claim 2, wherein the amino acid modification is R, N, D, C, Q, E, G, H, I, L, K, M, F, P, S, T, W, or Y; or (h) the amino acid modification is at position 91 in the heavy chain variable region, and the amino acid at position 91 is A, R, N, D, C, Q, E, G, H, I, L, K, F, P, S, T, W, Y, or V; or a combination of two or more modifications selected from (a) to (h).

4. 2. The antibody or antigen-binding fragment of claim 1, wherein the amino acid modifications comprise one or more of the following in the heavy chain variable region according to Kabat numbering: A47R, R45K, M55I, V78A, M80I, R82T, V89A, M91L.

5. 3. The antibody or antigen-binding fragment of claim 1, wherein the amino acid modification comprises: (a) a modification at amino acid position 54 in the light chain variable region; and / or (b) a modification at amino acid position 55 in the light chain variable region according to Kabat numbering.

6. 6. The antibody or antigen-binding fragment of claim 5, wherein: (a) the amino acid modification is at position 54 of the light chain variable region, and the amino acid at position 54 is A, R, N, D, C, Q, E, G, H, I, K, M, F, P, S, T, W, Y, or V; and / or (b) the amino acid modification is at position 55 of the light chain variable region, and the amino acid at position 55 is A, R, N, D, C, Q, E, G, H, I, K, M, F, P, S, T, W, Y, or V.

7. 6. The antibody or antigen-binding fragment of claim 5, wherein the amino acid modifications comprise L54P and / or L55W in the light chain variable region according to Kabat numbering.

8. The antibody or antigen-binding fragment of any one of claims 1 to 7, comprising a heavy chain CDR1 represented by SEQ ID NO: 1, a heavy chain CDR2 represented by any one of SEQ ID NOs: 2 to 5, a heavy chain CDR3 represented by any one of SEQ ID NOs: 6 to 9, a light chain CDR1 represented by SEQ ID NO: 10, a light chain CDR2 represented by SEQ ID NO: 11, and a light chain CDR3 represented by any one of SEQ ID NOs: 12 to 15.

9. 9. The antibody or antigen-binding fragment of any one of claims 1 to 8, comprising a heavy chain framework (FR) 1 represented by SEQ ID NO: 304, a heavy chain FR2 represented by SEQ ID NO: 305 or SEQ ID NO: 313, a heavy chain FR3 represented by any one of SEQ ID NOs: 306, 307, 314, or 315, a heavy chain FR4 represented by SEQ ID NO: 308, a light chain FR1 represented by SEQ ID NO: 309, a light chain FR2 represented by SEQ ID NO: 310, a light chain FR3 represented by SEQ ID NO: 311, or a light chain FR4 represented by SEQ ID NO: 312, or a combination thereof.

10. According to Kabat numbering, (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A, 270 G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 38 5P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G, (yy) L234F, L235E, and P331S, (zz) L234A, L235E, and G237A,(aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (eee) G237A, (fff) The antibody or antigen-binding fragment of any one of claims 1 to 9, comprising a human IgG1 Fc region comprising F241A, (ggg) V264A, (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of two or more selected from (a) to (uu).

11. The antibody or antigen-binding fragment of any one of claims 1 to 9, comprising a human IgG4 Fc region.

12. 10. The antibody or antigen-binding fragment of any one of claims 1 to 9, comprising an Fc region comprising a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 320-362.

13. 13. The antibody or antigen-binding fragment of any one of claims 1 to 12, comprising a monomeric fraction of at least about 80% as determined by size exclusion chromatography.

14. 14. The antibody or antigen-binding fragment of any one of claims 1 to 13, expressing at least about 20 μg / ml total antibody, optionally between about 20 μg / ml total antibody and 70 μg / mL total antibody.

15. An antibody or antigen-binding fragment thereof that binds to TL1A, comprising: a heavy chain variable region comprising: (a) an HCDR1 comprising the amino acid sequence set forth in SEQ ID NO: 1; (b) an HCDR2 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 2 to 5; and (c) an HCDR3 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 6 to 9; and a light chain variable region comprising: (d) an LCDR1 comprising the amino acid sequence set forth in SEQ ID NO: 10; (e) an LCDR2 comprising the amino acid sequence set forth in SEQ ID NO: 11; and (f) an LCDR3 comprising the amino acid sequence set forth in any one of SEQ ID NOs: 12 to 15; and a crystallizable fragment (Fc) region having reduced antibody-dependent cell-mediated cytotoxicity (ADCC) function compared to human IgG1 and / or reduced complement-dependent cytotoxicity (CDC) compared to human IgG1.

16. 16. The antibody or antigen-binding fragment of claim 15, wherein the human IgG1 comprises SEQ ID NO:

320.

17. The antibody or antigen-binding fragment of claim 15 or 16, wherein the ADCC function of the Fc region comprising reduced ADCC is reduced by at least about 50% compared to human IgG1.

18. The antibody or antigen-binding fragment of any one of claims 15 to 17, wherein the CDC function of the Fc region comprising reduced CDC is reduced by at least about 50% compared to human IgG1.

19. The Fc region is selected from the group consisting of (a) 297A, 297Q, 297G, or 297D, (b) 279F, 279K, or 279L, (c) 228P, (d) 235A, 235E, 235G, 235Q, 235R, or 235S, (e) 237A, 237E, 237K, 237N, or 237R, (f) 234A, 234V, or 234F, (g) 233P, (h) 328A, (i) 327Q or 327T, (j) 329A, 329G, 329Y, or 329R, (k) 331S, (l) 236F or 236R, (m) 238A, 238E, 238G, 238H, 238I, 238V, 238W, or 238Y, (n) 248A, (o) 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, or 254V, (p) 255N, (q) 256H, 256K, 256R, or 256V, (r) 264S, (s) 265H, 265K, 265S, 265Y, or 265A, (t) 267G, 267H, 267I, or 267K, (u) 268K, (v) 269N or 269Q, (w) 270A , 270G, 270M, or 270N, (x) 271T, (y) 272N, (z) 292E, 292F, 292G, or 292I, (aa) 293S, (bb) 301W, (cc) 304E, (dd) 311E, 311G, or 311S, (ee) 316F, (ff) 328V, (gg) 330R, (hh) 339E or 339L, (ii) 343I or 343V, (jj) 373A, 373G, or 373S, (kk) 376E, 376W, or 376Y, (ll) 380D, (mm) 382D or 382P, (nn) 385P, (oo) 424H, 424M, or 424V, (pp) 434I, (qq) 438G, (rr) 439E, 439H, or 439Q, (ss) 440A, 440D, 440E, 440F, 440M, 440T, or 440V, (tt) E233P, (uu) L235E, (vv) L234A and L235A, (ww) L234A, L235A, and G237A, (xx) L234A, L235A, and P329G, (yy) L234F, L235E, and P331S, (zz) L234A, L235E, and G237A,(aaa) L234A, L235E, G237A, and P331S, (bbb) L234A, L235A, G237A, P238S, H268A, A330S, and P331S (IgG1σ), (ccc) L234A, L235A, and P329A, (ddd) G236R and L328R, (eee) G237A, (fff) F241A, (ggg) V264A, ( The antibody or antigen-binding fragment of any one of claims 15 to 18, comprising a human IgG1 comprising (hhh) D265A, (iii) D265A and N297A, (jjj) D265A and N297G, (kkk) D270A, (lll) A330L, (mmm) P331A or P331S, or (nnn) any combination of two or more selected from (a) to (uu).

20. The antibody or antigen-binding fragment of any one of claims 15 to 18, comprising (i) a human IgG4 Fc region or (ii) a human IgG4 Fc region comprising (a) S228P, (b) S228P and L235E, or (c) S228P, F234A, and L235A according to Kabat numbering.

21. The antibody or antigen-binding fragment of any one of claims 15 to 18, comprising a human IgG2 Fc region; an IgG2-IgG4 cross-subclass Fc region; an IgG2-IgG3 cross-subclass Fc region; an IgG2 comprising H268Q, V309L, A330S, P331S (IgG2m4); or an IgG2 comprising V234A, G237A, P238S, H268A, V309L, A330S, P331S (IgG2σ).

22. The Fc region is 329A, 329G, 329Y, 331S, 236F, 236R, 238A, 238E, 238G, 238H, 238I, 238V, 238W, 238Y, 248A, 254D, 254E, 254G, 254H, 254I, 254N, 254P, 254Q, 254T, 254V, 264S, 265H according to Kabat numbering. , 265K, 265S, 265Y, 265A, 267G, 267H, 267I, 267K, 434I, 438G, 439E, 439H, 439Q, 440A, 440D, 440E, 440F, 440M, 440T, and 440V.

23. 19. The antibody or antigen-binding fragment of any one of claims 15 to 18, comprising a sequence that is at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identical to any one of SEQ ID NOs: 320 to 362.

24. 19. The antibody or antigen-binding fragment of any one of claims 15-18, wherein the Fc region comprises any one of SEQ ID NOs: 401-413, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 401-413.

25. 19. The antibody or antigen-binding fragment of any one of claims 15 to 18, wherein the heavy chain comprises any one of SEQ ID NOs: 501-513, or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs: 501-513.

26. 26. The antibody or antigen-binding fragment of any one of claims 15 to 25, wherein the light chain comprises any one of SEQ ID NOs: 514 or a sequence at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% identical to any one of SEQ ID NOs:

514.

27. 27. The antibody or antigen-binding fragment of any one of claims 15 to 26, comprising at least about 80% monomer fraction as determined by size exclusion chromatography.

28. 28. The antibody or antigen-binding fragment of any one of claims 15 to 27, expressing at least about 20 μg / ml total antibody, optionally between about 20 μg / ml total antibody and 70 μg / mL total antibody.

29. 29. A method of treating inflammatory bowel disease (IBD) in a subject in need thereof, comprising administering to the subject the antibody or antigen-binding fragment of any one of claims 1 to 28.

30. 30. The method of claim 29, wherein the subject is suffering from fibrosis.

31. 30. The method of claim 29, wherein the IBD comprises Crohn's disease.

32. 30. The method of claim 29, wherein the IBD comprises ulcerative colitis.

33. 29. A liquid composition comprising the antibody or antigen-binding fragment of any one of claims 1 to 28, wherein the liquid composition comprises an antibody or antigen-binding fragment concentration of 10 mg / ml to 170 mg / ml.

34. A liquid composition comprising an antibody or antigen-binding fragment thereof that binds to TL1A, wherein the antibody or antigen-binding fragment thereof is at a concentration of 10 mg / ml to 170 mg / ml.

35. 35. The liquid composition of claim 33 or 34, comprising a pharmaceutically acceptable excipient.

36. 36. The liquid composition of any one of claims 33 to 35, having a viscosity of from about 4 to about 30 mPa-s (milliPascal seconds (mPa·s)).

37. 36. The liquid composition of any one of claims 33 to 35, having a viscosity of about 4 to about 10 mPa-s (milliPascal seconds (mPa·s)).

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