Anti-TL1A antibody or antigen-binding fragment thereof, isolated polynucleotide, nucleic acid construct, cell and pharmaceutical composition.

Description

1 / 53 “ANTI-TL1A ANTIBODY OR ANTIGEN-BINDING FRAGMENT THEREOF, ISOLATED POLYNUCLEOTIDE, NUCLEIC ACID CONSTRUCTION, CELL AND PHARMACEUTICAL COMPOSITION FIELD OF THE INVENTION

[001] The present invention relates to the field of antibody therapies, specifically to an anti-TL1A antibody, its method of preparation and uses. BACKGROUND OF THE INVENTION

[002] Inflammatory bowel disease (IBD) is a specific chronic inflammatory condition of the intestine, comprising Crohn's disease (CD) and ulcerative colitis (UC). The etiology and pathogenesis of inflammatory bowel disease remain obscure, although it is widely recognized that it arises from the interaction of multiple factors, including abnormal immune regulation of the intestinal mucosa, persistent intestinal infection, impairment of the integrity of the intestinal mucosal barrier, and genetic and environmental influences. Both innate and adaptive immune responses in the intestinal mucosa contribute to the development of IBD lesions, with abnormal mucosal immune responses constituting a key factor in mucosal tissue damage.

[003] The TNF 1A ligand (also known as tumor necrosis factor superfamily member 15 [TNFSF15]) belongs to the TNF ligand superfamily and, like other members, forms a homotrimeric complex. TL1A is a type II transmembrane protein that exists in both membrane-bound and soluble forms, with two distinct receptors: DR3 and soluble decoy receptor 3 (DcR3). DR3, also known as APO3, LARD, or WSL1, belongs to the tumor necrosis factor receptor (TNFRSF) superfamily. TL1A is a ligand for DR3; upon binding, it induces the activation of nuclear factor kappa B (NF-κB), promoting Petition 870250088681, dated 09 / 30 / 2025, p. 16 / 90 2 / 53 thus the transcription of inflammatory cytokines and activating apoptotic proteases, exerting pro-inflammatory and pro-apoptotic effects; DcR3 binds competitively to TL1A, thus attenuating the generation of co-stimulatory signals from T cells and exerting anti-apoptotic effects, along with suppression of the secretion of pro-inflammatory cytokines.

[004] Recent studies reveal that TL1A promotes inflammation and fibrosis of the intestinal mucosa, influencing the activation and proliferation of T cells in the intestinal epithelial lamina propria, promoting Th1 cell polarization and effector functions, and positively regulating IFN-γ expression. In parallel, TL1A acts on Th17 cells to increase IL-17 secretion, inducing intestinal mucosal dysregulation and triggering inflammatory responses. Chronic inflammation serves as the main initiator of intestinal fibrosis, further activating intestinal fibroblasts to produce excessive extracellular matrix (ECM), ultimately leading to fibrosis formation. Consequently, TL1A may promote chronic intestinal fibrosis associated with experimental colitis by regulating IL-17 and IFN-γ.The anti-TL1A antibody effectively inhibits TL1A-induced secretion of IFN-γ and TNF-α by human peripheral blood mononuclear cells (PBMCs), while simultaneously suppressing TL1A-induced apoptosis. Therefore, it can be used to treat inflammatory bowel diseases and related conditions. SUMMARY OF THE INVENTION

[005] Considering the aforementioned deficiencies of the prior art, the present invention aims to provide an anti-TL1A antibody, its method of preparation and uses, thereby solving the problems of the prior art.

[006] To achieve the aforementioned objective and other related objectives, the present invention provides a Petition 870250088681, dated 09 / 30 / 2025, page 17 / 90 3 / 53 anti-TL1A antibody or antigen-binding fragment thereof, wherein said antibody or antigen-binding fragment comprises a variable heavy chain region and a variable light chain region. The anti-TL1A antibody or antigen-binding fragment thereof exhibits multiple of the following technical characteristics: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 10 or 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in SEQ ID No.: 11, 19, 39, 40 or 41; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 12, 20 or 42; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in SEQ ID No.: 13 or 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in SEQ ID No.: 14 or 22; <6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Sequence ID No. 15 or 23.

[007] The present invention also provides a recombinant protein, wherein said recombinant protein possesses: (i) said anti-TL1A antibody or antigen-binding fragment thereof; and (ii) optionally, a labeling sequence to facilitate expression and / or purification.

[008] The present invention also provides an isolated polynucleotide, in which said polynucleotide encodes the variable region of the heavy chain and / or the variable region of the light chain. Petition 870250088681, dated 09 / 30 / 2025, p. 18 / 90 4 / 53 or the complete amino acid sequence of said anti-TL1A antibody or antigen-binding fragment thereof, or encodes said recombinant protein.

[009] The present invention further provides a nucleic acid construct comprising said isolated polynucleotide. [00l0] The present invention also provides a cell containing said construct or a genome in which said exogenous polynucleotide is integrated. [00ll] The present invention further provides a method for preparing said anti-TL1A antibody or antigen-binding fragment thereof, comprising the following steps: cultivating said cells under suitable conditions to express said TL1A antibody or its antigen-binding fragment, thereby expressing said TL1A antibody or its antigen-binding fragment; furthermore, said method additionally comprises the step of purifying and / or separating said TL1A antibody or its antigen-binding fragment.

[0012] The present invention also provides the use of said anti-TL1A antibody or antigen-binding fragment thereof, or said recombinant protein, in the preparation of therapeutic agents for diseases or in the preparation of diagnostic agents for diseases.

[0013] In the present invention, the aforementioned is selected from inflammatory bowel disease, gastrointestinal diseases associated with cystic fibrosis, colitis, irritable bowel syndrome, eosinophilic esophagitis, atopic dermatitis, eczema, scleroderma, arthritis or rheumatoid arthritis, alone or in combination. Wherein, inflammatory bowel disease refers to Crohn's disease or ulcerative colitis.

[0014] The present invention also provides a pharmaceutical composition comprising said anti-TL1A antibody or Petition 870250088681, dated 09 / 30 / 2025, p. 19 / 90 5 / 53 its aforementioned antigen-binding fragment, or the aforementioned recombinant protein.

[0015] The present invention also provides a method for treating the disease, comprising administering the aforementioned anti-TL1A antibody or its antigen-binding fragment, the aforementioned recombinant protein, or the aforementioned pharmaceutical composition of the present invention to a subject in need.

[0016] As mentioned above, the anti-TL1A antibody or antigen-binding fragment thereof of the present invention exhibits the following beneficial effects: it effectively inhibits the secretion of IFN-γ and TNF-α by TL1A-induced human peripheral blood mononuclear cells (PBMCs) and suppresses TL1A-induced apoptosis. This suggests that said antibody or its composition may be employed for the treatment of inflammatory bowel disease, gastrointestinal disorders associated with cystic fibrosis, Crohn's disease, colitis, ulcerative colitis, irritable bowel syndrome, eosinophilic esophagitis, atopic dermatitis, eczema, scleroderma, arthritis, or rheumatoid arthritis.

[0017] It should be understood that, within the scope of the present invention, the technical features described above and those specifically described below the present invention (for example, in the implementation example) can be mutually combined to constitute new or preferred technical solutions. Due to space limitations, these are not exhaustively enumerated in this document. DESCRIPTION OF THE DRAWINGS

[0018] Figures 1A to 1C show the binding capacity results of the investigational mouse-derived antibody with the human TL1A-His target antigen in implementation example 1. Petition 870250088681, dated 09 / 30 / 2025, p. 20 / 90 6 / 53

[0019] Figures 2A to 2C show the results of the antibody blocking activity assay of investigational mouse-derived antibodies against the TL1A protein binding activity of the stably transfected 293FT-DR3 cell line in implementation example 2.

[0020] Figure 3A shows the affinity ELISA results for the candidate antibodies obtained after optimizing the physicochemical properties of the humanized antibodies 72851, 31122 and the humanized antibody 31122, demonstrating their binding to the TL1A-His antigen in implementation example 4.

[0021] Figure 3B shows the experimental results of capillary electrophoresis for the candidate antibodies obtained from the optimization of the physicochemical properties of the humanized antibodies 72851, 31122 and the optimized humanized antibody 31122 in implementation example 4.

[0022] Figure 4 shows the experimental results of blocking the TL1A-DR3 binding by the anti-TL1A antibody in implementation example 5.

[0023] Figure 5 shows the experimental results of the anti-TL1A antibody inhibiting the NF-kB signaling pathway in the TL1A TF-1 cell line, as demonstrated in implementation example 6.

[0024] Figure 6 shows the results of the anti-TL1A antibody inhibiting TL1A-induced apoptosis in TF-1 cells, as demonstrated in implementation example 7.

[0025] Figure 7 shows the results of the anti-TL1A antibody inhibiting TL1A-stimulated IFNγ secretion in cells, as demonstrated in implementation example 8.

[0026] Figure 8 shows the results of the anti-TL1A antibody inhibiting TL1A-stimulated TNFα secretion in cells, as demonstrated in implementation example 9.

[0027] Figure 9A shows the results of the affinity ELISA. Petition 870250088681, dated 09 / 30 / 2025, page 21 / 90 7 / 53 for the humanized antibody 72581 binding to human, cynomolgus monkey, mouse and mouse TL1A proteins, as shown in implementation example 10.

[0028] Figures 9B to 9E show the results of the pharmacological efficacy of the anti-TL1A antibody in the DSS-induced chronic inflammatory bowel disease model in mice in implementation example 10.

[0029] Figures 10A and 10B show the results of the pharmacological efficacy of the anti-TL1A antibody in the TNBS-induced acute inflammatory bowel disease model in mice in implementation example 11. DETAILED DESCRIPTION OF THE INVENTION

[0030] The present invention provides an anti-TL1A antibody or antigen-binding fragment thereof, wherein said antibody or antigen-binding fragment comprises a variable heavy chain region and a variable light chain region. Said anti-TL1A antibody or antigen-binding fragment thereof exhibits multiple of the following technical features: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 10 or 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in SEQ ID No.: 11, 19, 39, 40 or 41; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 12, 20 or 42; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in SEQ ID No.: 13 or 21; Petition 870250088681, dated 09 / 30 / 2025, page 22 / 90 8 / 53 < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in SEQ ID No.: 14 or 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Seq ID No. 15 or 23. In certain embodiments of the present invention, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 10; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 11; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 12; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Sequence ID No.: 13; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Sequence ID No.: 14; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Sequence ID No.: 15.

[0031] In certain embodiments of the present invention, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 18; Petition 870250088681, dated 09 / 30 / 2025, page 23 / 90 9 / 53 < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 19; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 20; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Sequence ID No.: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Sequence ID No.: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Sequence ID No.: 23.

[0032] In certain embodiments of the present invention, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 39; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 20; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Sequence ID No.: 21; Petition 870250088681, dated 09 / 30 / 2025, page 24 / 90 10 / 53 < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Sequence ID No.: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Sequence ID No.: 23.

[0033] In certain embodiments of the present invention, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 40; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 20; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Sequence ID No.: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Sequence ID No.: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Sequence ID No.: 23.

[0034] In certain embodiments of the present invention, said anti-TL1A antibody or antigen-binding fragment thereof comprises: Petition 870250088681, dated 09 / 30 / 2025, page 25 / 90 11 / 53 < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 41; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 20; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Sequence ID No.: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Sequence ID No.: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Sequence ID No.: 23.

[0035] In certain embodiments of the present invention, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 39; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 42; Petition 870250088681, dated 09 / 30 / 2025, page 26 / 90 12 / 53 < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Sequence ID No.: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Sequence ID No.: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Sequence ID No.: 23.

[0036] In certain embodiments of the present invention, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 40; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 42; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Sequence ID No.: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Sequence ID No.: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Sequence ID No.: 23.

[0037] In certain embodiments of the present invention, said anti-TL1A antibody or binding fragment to Petition 870250088681, dated 09 / 30 / 2025, page 27 / 90 13 / 53 antigen of the same comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Sequence ID No.: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 41; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 42; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Sequence ID No.: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Sequence ID No.: 22; <6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Sequence ID No. 23.

[0038] CDR (Complementarity Determinant Region) typically denotes the region within an antibody that can form spatial complements with antigenic determinants. Antibody variability is not uniformly distributed throughout the variable region. The variable regions of the heavy chain and light chain of monoclonal antibodies generally contain three hypervariable regions (HVRs). Because these regions generally exhibit spatial complementarity with antigenic determinants, hypervariable regions are also called complementarity-determining regions (CDRs). The variable region of the heavy chain generally comprises three CDRs: HVR1, HVR2, and HVR3. On the other hand, the variable region of the light chain generally comprises... Petition 870250088681, dated 09 / 30 / 2025, page 28 / 90 14 / 53 three CDRs: LCDR1, LCDR2 and LCDR3.

[0039] In certain embodiments of the present invention, the variable region of the heavy chain and the variable region of the light chain may additionally comprise structural frames. Said structural frames may be positioned between complementarity-determining regions or at either end of the complementarity-determining regions. In certain specific embodiments of the present invention, the sequence of said structural frame is derived from the variable region of a human monoclonal antibody, or from the sequence of the structural frame of a mouse monoclonal antibody that has undergone substitution, deletion or insertion of multiple (specifically 1-50, 1-30, 1-20, 1-10, 1-5 or 1-3) amino acids, wherein the amino acid sequence of the structural region may exhibit 80%, 85%, 90%, 93%, 95%, 97% or 99% or more homology with the sequence of the structural region of the variable region of the human monoclonal antibody.

[0040] In certain embodiments of the present invention, the amino acid sequence of the variable region of the anti-TL1A antibody heavy chain or antigen-binding fragment thereof is that shown in any of the following SEQ ID No.: 3, SEQ ID No.: 16, SEQ ID No.: 7, SEQ ID No.: 24 or SEQ ID No.: 26-31.

[0041] In certain embodiments of the present invention, the amino acid sequence of the variable region of the anti-TL1A antibody light chain or antigen-binding fragment thereof is as shown in SEQ ID No.: 5, SEQ ID No.: 17, SEQ ID No.: 9 or SEQ ID No.: 25.

[0042] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 3, and the sequence Petition 870250088681, dated 09 / 30 / 2025, page 29 / 90 15 / 53 of the amino acids in the variable region of the light chain is shown in N° ID SEQ: 5.

[0043] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 16, and the amino acid sequence of the variable region of the light chain is that shown in No. ID SEQ: 17.

[0044] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 7, and the amino acid sequence of the variable region of the light chain is that shown in No. ID SEQ: 9.

[0045] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 24, and the amino acid sequence of the variable region of the light chain is that shown in No. ID SEQ: 25.

[0046] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 26, and the amino acid sequence of the variable region of the light chain is that shown in No. ID SEQ: 25.

[0047] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 27, and the amino acid sequence of the variable region of the light chain is that shown in No. ID SEQ: 25. Petition 870250088681, dated 09 / 30 / 2025, page 30 / 90 16 / 53

[0048] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 28, and the amino acid sequence of the variable region of the light chain is that shown in No. ID SEQ: 25.

[0049] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 29, and the amino acid sequence of the variable region of the light chain is that shown in No. ID SEQ: 25.

[0050] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 30, and the amino acid sequence of the variable region of the light chain is that shown in No. ID SEQ: 25.

[0051] In certain embodiments of the present invention, the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is that shown in No. ID SEQ: 31, and the amino acid sequence of the variable region of the light chain is that shown in No. ID SEQ: 25.

[0052] In certain embodiments of the present invention, said anti-TL1A antibody or antigen-binding fragment thereof comprises monomeric, bivalent and / or multivalent antibodies.

[0053] In certain embodiments of the present invention, said antigen-binding fragment is selected from scFv, Fab, Fab', F(ab')2, Fv fragment, heavy chain antibody and disulfide-linked Fv (dsFv). Petition 870250088681, dated 09 / 30 / 2025, page 31 / 90 17 / 53

[0054] In certain embodiments of the present invention, the constant region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is selected from the constant regions of the heavy chain of human IgG1, IgG2, IgG3 or IgG4; preferably, it is the constant region of the human IgG1 heavy chain.

[0055] In certain embodiments of the present invention, the constant region of the light chain of said anti-TL1A antibody or antigen-binding fragment thereof is selected from the constant regions of the κ chain or the λ chain of said human antibody; preferably, it is the constant region of the κ chain.

[0056] The amino acid sequence of the variable region of the heavy chain or the variable region of the light chain of said anti-TL1A antibody or antigen-binding fragment thereof further comprises derived sequences obtained by optional addition, omission, modification and / or substitution of at least one amino acid in the aforementioned sequence, while maintaining TL1A binding affinity. In another preferred embodiment, a derived sequence comprising 1 to 5 amino acids, for example 1, 2 or 3 amino acids, with addition, omission, modification and / or substitution in any of the aforementioned amino acid sequences, wherein a derived antibody formed by VH and VL containing said derived CDR sequence maintains the affinity to bind to TL1A.

[0057] Said anti-TL1A antibody or antigen-binding fragment thereof is selected from a complete antibody, a monochain antibody or an antibody fragment.

[0058] A complete antibody comprises variable (V) regions and constant (C) regions. The constant regions include the constant region of the light chain (LC) and the constant region of the chain Petition 870250088681, dated 09 / 30 / 2025, page 32 / 90 18 / 53 heavy (HC). The constant regions may be those of the natural amino acid sequence or variants thereof. The constant regions of the natural sequence are, for example, those of mammals, such as humans. In certain embodiments of the present invention, the constant region of the heavy chain is an IgG1 constant region and / or the constant region of the light chain is a kappa chain constant region (i.e., κ chain constant region). In certain embodiments of the present invention, the amino acid sequence of the heavy chain constant region is that shown in SEQ ID No. 33 and / or the amino acid sequence of the light chain constant region is that shown in SEQ ID No. 34.

[0059] The antibody fragment comprises a part of a complete antibody, preferably including its antigen-binding region or variable region. For example, antibody fragments comprise Fab, Fab', F(ab'), F(ab')2, and Fv fragments. An Fv fragment is an antibody fragment that contains a complete antigen recognition and binding site. This region comprises a variable region of the heavy chain and a variable region of the light chain closely linked to each other, where this linkage may be covalent (e.g., in scFv). In this conformation, the three CDRs of each variable region interact to define the antigen-binding site on the surface of the VV dimer. The Fab fragment comprises the variable region and the constant region of the light chain, and the variable region and the first constant region (CH1) of the heavy chain.An F antibody fragment (ab') comprises a pair of Fab fragments, typically covalently linked near their carboxylic termini via a jointed cysteine ​​residue.

[0060] The present invention further provides a recombinant protein, wherein said recombinant protein has: (i) said anti-TL1A antibody or binding fragment. Petition 870250088681, dated 09 / 30 / 2025, page 33 / 90 19 / 53 antigen of the same; and (ii) optionally, a labeling sequence to facilitate expression and / or purification.

[0061] In certain embodiments of the present invention, said marking sequence comprises an Fc marking, HA marking, GGGS sequence, FLAG marking, Myc marking, 6His marking or combinations thereof.

[0062] In certain embodiments of the present invention, said recombinant protein comprises a fusion protein.

[0063] In certain embodiments of the present invention, said recombinant protein is a monomer, dimer or polymer.

[0064] The present invention also provides an isolated polynucleotide encoding the variable region of the heavy chain and / or the variable region of the light chain or the complete amino acid sequence of the anti-TL1A antibody or antigen-binding fragment thereof, or encoding said recombinant protein.

[0065] In certain embodiments of the present invention, said polynucleotide is selected from RNA (e.g., mRNA) or DNA (e.g., cDNA).

[0066] In certain embodiments of the present invention, the nucleotide sequences encoding the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof are those shown in SEQ ID No. 2, SEQ ID No. 6, SEQ ID No. 35, SEQ ID No. 37 and SEQ ID No. 43-48.

[0067] In certain embodiments of the present invention, the nucleotide sequence encoding the variable region of the light chain of the anti-TL1A antibody or antigen-binding fragment thereof is as shown in SEQ ID No. 4, SEQ ID No. 8, SEQ ID No. 36 or SEQ ID No. 38.

[0068] The present invention also provides a construction of Petition 870250088681, dated 09 / 30 / 2025, p. 34 / 90 20 / 53 nucleic acid comprising said isolated polynucleotide.

[0069] In certain embodiments of the present invention, said nucleic acid construct is selected from the group: DNA, RNA, viral vectors, plasmids, transposons, other gene transfer systems or combinations thereof.

[0070] In certain embodiments of the present invention, said nucleic acid construct comprises viral vectors, such as lentiviruses, adenoviruses, AAV viruses, retroviruses or combinations thereof.

[0071] In certain embodiments of the present invention, said nucleic acid construct is a plasmid, a retrovirus, or a lentiviral vector.

[0072] In certain embodiments of the present invention, said nucleic acid construct is selected from the group: lentiviral vector pTomo, plenti, pLVTH, pLJMl, pHCMV, pLBS.CAG, pHR, pLV, etc.

[0073] In certain embodiments of the present invention, said nucleic acid construct further comprises selected elements from the group consisting of: a promoter, a transcription enhancer element (WPRE), a long terminal repeat (LTR), etc.

[0074] The term nucleic acid construct denotes an artificially engineered nucleic acid segment capable of being introduced into target cells or tissues. The said nucleic acid construct may be various expression vectors, wherein said expression vectors comprise a vector frame, i.e., empty vector, and an expression frame. The term expression frame denotes a sequence that has the potential to encode a protein.

[0075] The type of expression vector is not specifically limited. An expression vector refers to a molecule of Petition 870250088681, dated 09 / 30 / 2025, page 35 / 90 21 / 53 nucleic acid that allows the insertion of exogenous nucleotides without impairing the vector's ability to replicate and / or integrate into host cells. An expression vector may comprise nucleic acid sequences that allow replication in host cells, such as an origin of replication. The expression vector may also incorporate multiple selective marker genes and other genetic elements. The expression vector comprises essential regulatory sequences that allow the transcription and translation of one or more inserted genes. The expression vector is selected from either eukaryotic expression vectors or prokaryotic expression vectors.

[0076] Prokaryotic expression vectors are selected from Escherichia coli expression vectors, Bacillus subtilis expression vectors, or Streptomyces expression vectors. In a preferred implementation, the prokaryotic expression vector is selected from Escherichia coli expression vectors. The E. coli expression system, compared to other systems, provides a clearly defined genetic background, shorter culture cycles, high levels of target gene expression, and robust resistance to contamination. The E. coli expression vector may, for example, be a pET expression vector, specifically pET28a or pET32a, capable of stable expression in E. coli. The expression vector may also comprise pCW expression vectors or pUC expression vectors.

[0077] The eukaryotic expression vector mentioned is selected from yeast expression vectors, insect expression vectors, or mammalian expression vectors. The mammalian expression vector mentioned is selected from retroviral expression vectors, Petition 870250088681, dated 09 / 30 / 2025, page 36 / 90 22 / 53 lentiviral expression vectors, adenoviral expression vectors, or adeno-associated viral expression vectors. In a preferred embodiment, said eukaryotic expression vector is selected from retroviral expression vectors, which can be stably expressed in cell lines; an example of a retroviral vector is pMSCV.

[0078] Said host cell is selected from eukaryotic host cells or prokaryotic host cells. The eukaryotic host cell is selected from fungi, such as yeasts, insects, birds, plants, Caenorhabditis elegans (C. elegans) or nematodes, or mammalian host cells. A non-limiting example of insect cells are Spodoptera frugiperda (Sf) cells. Examples of yeast host cells include Saccharomyces cerevisiae, Kluyveromyces lactis (K. lactis), or Yarrowia lipolytica.Examples of mammalian host cells include COS cells, hamster kidney cells, mouse L cells, LNCaP cells, Chinese hamster ovary (CHO) cells, human embryonic kidney (HEK) cells, African green monkey cells, CV1 cells, Vero cells, or Hep-2 cells. Examples of prokaryotic host cells include bacterial cells such as Escherichia coli, Streptomyces, Bacillus subtilis, Salmonella typhi, or mycobacteria.

[0079] Experts in the field can obtain cells containing the gene encoding the anti-TL1A antibody or its antigen-binding fragment by transfecting the expression vector into host cells using well-known methods in the field. For example, the introduction of the expression vector into eukaryotic cells can be performed via coprecipitation with calcium phosphate, hole transfection, microinjection, liposome transfection, or transfection using reagents. Petition 870250088681, dated 09 / 30 / 2025, page 37 / 90 23 / 53 transfection with polyamine.

[0080] The present invention further provides a cell containing said construct or a genome in which said exogenous polynucleotide is integrated.

[0081] The cells mentioned in the present invention are obtained by transforming the aforementioned nucleic acid construct into host cells.

[0082] In certain embodiments of the present invention, said cells comprise prokaryotic cells or eukaryotic cells.

[0083] In certain embodiments of the present invention, said cells are selected from the group consisting of: Escherichia coli, yeast cells and mammalian cells.

[0084] The present invention further provides a method for preparing said anti-TL1A antibody or antigen-binding fragment thereof, comprising the following steps: cultivating said cells under suitable conditions to express said TL1A antibody or its antigen-binding fragment, thereby expressing said TL1A antibody or its antigen-binding fragment; furthermore, said method additionally comprises the step of purifying and / or separating said TL1A antibody or its antigen-binding fragment.

[0085] The present invention also provides the use of said anti-TL1A antibody or antigen-binding fragment thereof, or said recombinant protein, in the preparation of therapeutic agents for diseases or in the preparation of diagnostic agents for diseases.

[0086] In the present invention, the aforementioned is selected from inflammatory bowel disease, gastrointestinal diseases associated with cystic fibrosis, colitis, irritable bowel syndrome, eosinophilic esophagitis, atopic dermatitis, eczema, scleroderma, arthritis or rheumatoid arthritis, alone or Petition 870250088681, dated 09 / 30 / 2025, p. 38 / 90 24 / 53 in combination. In which case, inflammatory bowel disease refers to Crohn's disease or ulcerative colitis.

[0087] The present invention further provides a pharmaceutical composition comprising said anti-TL1A antibody or antigen-binding fragment thereof of the present invention, or said recombinant protein described herein.

[0088] In certain embodiments of the invention, the pharmaceutical composition comprises the anti-TL1A antibody or antigen-binding fragment thereof of the present invention, or the recombinant protein described herein, and a pharmacologically acceptable vector or excipient.

[0089] “Pharmacologically acceptable means that, when administered appropriately to animals or humans, they do not produce adverse, allergic or other undesirable reactions.

[0090] Pharmacologically acceptable vectors must be compatible with the active ingredient in question, that is, they must be miscible with it without substantially diminishing the drug's efficacy under normal conditions.Specific examples of substances that may serve as a pharmacologically acceptable vector or excipient include sugars, such as lactose, glucose, and sucrose; starches, such as corn starch and potato starch; cellulose and its derivatives, such as sodium methylcellulose, ethylcellulose, and methylcellulose; powdered gum arabic; malt; gelatin; talc; solid lubricants, such as stearic acid and magnesium stearate; calcium sulfate; vegetable oils, including peanut oil, cottonseed oil, sesame oil, olive oil, corn oil, and cocoa butter; polyols, such as propylene glycol, glycerol, sorbitol, mannitol, and polyethylene glycol; alginic acid; emulsifiers, such as Tween; humectants, such as sodium lauryl sulfate; colorants; flavorings; and other agents. Petition 870250088681, dated 09 / 30 / 2025, page 39 / 90 25 / 53 compression, stabilizers; antioxidants; preservatives; isopyrogenic water; isotonic saline solutions; and phosphate buffers, etc. These substances are used as needed to aid in the stability of the formulation, enhance activity or bioavailability, or to create a pleasant taste or odor when ingested orally.

[0091] The form of the said pharmaceutical composition is not specifically restricted and may be solid, liquid, gel, semi-fluid, aerosol or any other material form.

[0092] The aforementioned pharmaceutical composition is intended primarily for use in mammals. The aforementioned mammals are preferably rodents, artiodactyls, perissodactyls, lagomorphs, primates, etc. The aforementioned primates are preferably monkeys, apes or humans.

[0093] The prepared pharmaceutical composition can be administered by conventional routes, including but not limited to: intravenous injection, intravenous infusion, subcutaneous injection, local injection, intramuscular injection, intratumoral injection, intraperitoneal injection (e.g., intraperitoneal), intracranial injection or intraluminal injection.

[0094] The present invention also provides a method for treating the disease, comprising administering the aforementioned anti-TL1A antibody or its antigen-binding fragment, the aforementioned recombinant protein or the aforementioned pharmaceutical composition of the present invention to a subject in need.

[0095] In certain embodiments of the present invention, the subject comprises mammals, such as human beings.

[0096] In certain embodiments of the present invention, Petition 870250088681, dated 09 / 30 / 2025, page 40 / 90 26 / 53 the aforementioned is selected from inflammatory bowel disease, gastrointestinal disorders associated with cystic fibrosis, colitis, irritable bowel syndrome, eosinophilic esophagitis, atopic dermatitis, eczema, scleroderma, arthritis or rheumatoid arthritis, alone or in combination. Wherein, inflammatory bowel disease refers to Crohn's disease or ulcerative colitis.

[0097] In certain embodiments of the present invention, said method may be used in combination with other therapeutic methods.

[0098] In certain embodiments of the present invention, said other therapeutic methods include chemotherapy, radiotherapy, targeted therapy and the like.

[0099] In treating the disease, a safe and effective amount of the antibody or its antigen-binding fragment is administered to the subject. This safe and effective dose is typically at least approximately 10 micrograms per kilogram of body weight and, in most cases, does not exceed approximately 50 milligrams per kilogram of body weight. Preferably, the dose is approximately 10 micrograms per kilogram of body weight to approximately 10 milligrams per kilogram of body weight. Naturally, specific dosages should also consider factors such as the route of administration and the patient's health status, which fall within the scope of a qualified professional's expertise.

[00100] Specific examples of how the present invention is implemented follow. Those skilled in the art will easily understand other advantages and functions of the present invention from the content disclosed in this specification.The present invention can also be implemented or applied in different ways, and the details of this are described. Petition 870250088681, dated 09 / 30 / 2025, page 41 / 90 27 / 53 description may be modified or altered based on different viewpoints and applications without departing from the spirit of the invention.

[00101] Additionally, before proceeding with the description of specific embodiments of the present invention, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments referred to below; it should also be understood that the terminology used in the embodiments of the present invention is intended to describe specific embodiments and not to limit the scope of protection of the invention. In the specification and claims of the present invention, unless expressly stated otherwise in the text, singular forms such as a, an, and this include plural forms.

[00102] When an implementation example provides a numerical range, it should be understood that, unless otherwise indicated in the present invention, any value within that range, including any endpoint and any value between them, may be selected. Unless otherwise indicated, all technical and scientific terms used in the present invention shall have the same meaning as is commonly understood by those skilled in the relevant technical field. In addition to the specific methods, apparatus, and materials employed in the implementation examples, any prior art method, apparatus, or material that is similar or equivalent to those referred to in the implementation examples of the present invention may be used to practice the present invention, based on the prior art knowledge possessed by a person skilled in the art and in the disclosure of the present invention.Unless otherwise indicated, percentages and parts refer to percentages by weight and parts by weight. Petition 870250088681, dated 09 / 30 / 2025, page 42 / 90 28 / 53

[00103] Implementation Example 1: Preparation and screening of animals immunized with antigen and hybridomas a. Preparation of the antigen protein and the positive control antibody.

[00104] The human TL1A extracellular domain (TL1A-ECD) sequence used as an antigen was obtained from the UniProt database (Entry: O95150), with the amino acid sequence shown in SEQ ID No.: 1. A 6*His label was added to its N-terminus and constructed in the pcDNA 3.4 expression vector. HEK-293F cells were transfected and, after 5 days of expression, the cell culture supernatant was collected and purified to obtain the TL1A-His protein. Similarly, after replacing the aforementioned 6*His label with the human IgG1 Fc sequence and transfecting HEK-293F cells, the TL1A-Fc protein was obtained after expression and purification. The pra023 positive control antibody sequence is derived from patent WO-2021081365-A1.

[00105] SEQ ID No.: 1 LKGQEFAPSHQQVYAPLRADGDKPRAHLTVVRQTPTQHFKNQFPALHWEHELGLAF TKNRMNYTNKFLLIPESGDYFIYSQVTFRGMTSECSEIRQAGRPNKPDSITVVITK VTDSYPEPTQLLMGTKSVCEVGSNWFQPIYLGAMFSLQEGDKLMVNVSDISLVDYT KEDKTFFGAFLL a. Immunization of mice

[00106] Experimental female Balb / c mice, aged 6–8 weeks. After acquisition, mice were housed in the laboratory environment for one week, acclimated to a 12 / 12 hour light / dark cycle, maintained at 20–25 °C and humidity levels of 40–60%. Balb / c mice were routinely immunized with the human TL1A-His protein expressed in implementation example 1.1 as an immunogen. A dose of 50 μg per mouse in 0.2 ml was administered intraperitoneally (IP) in 3 immunizations on days 0, 14, and 28. Petition 870250088681, dated 09 / 30 / 2025, p. 43 / 90 29 / 53 Blood samples were collected on days 21 and 35 to detect antibody titers in mouse serum using the ELISA method. After the 3 immunizations, mice with high serum antibody titers were selected. These mice were stimulated with human TL1A-His protein (50 μg / mouse / 0.2 ml) by intraperitoneal (IP) injection. 3 to 4 days later, spleens were harvested for fusion experiments. a. Preparation and selection of hybridoma cells

[00107] Four days after final immunization, mouse splenocytes were fused with SP2 / 0 mouse myeloma cells via PEG fusion using standard hybridoma protocols. The fused cells were uniformly suspended in complete medium, defined as RPMI 1640-GLUMAX supplemented with 1% penicillin-streptomycin, 20% FBS (fetal bovine serum), and 1x HAT. The fused cells were seeded at 4 χ¹⁰⁴ cells / 200 μL per well in 60 χ¹⁶ well plates. After 712 days, the supernatants were collected, and hybridoma wells exhibiting positive binding activity to human TL1A were selected by ELISA.

[00108] The ELISA method for screening hybridoma wells positive for human TL1A binding activity is as follows: Dilute TL1A-His in PBS buffer to 1 μg / mL. Add 100 μL per well to the plate and incubate overnight at 4 °C. The next day, discard the supernatant. Add 5% skimmed milk powder and block at 37 °C for 1 hour. Wash the plate 3 times with PBST and reserve. The hybridoma supernatant collected sequentially to the blocked plate is added at 100 μL per well and incubated at 37 °C for 1 hour. Wash the plate 3 times with PBST, the HRP-labeled goat anti-mouse IgG secondary antibody is added and incubated at 37 °C for 30 minutes. After 3 washes with PBST, the residual liquid is dried on absorbent paper. Add 100 Petition 870250088681, dated 09 / 30 / 2025, p. 44 / 90 30 / 53 pL of TMB is added to each well and incubated at room temperature (20±5 °C) in the dark for 5 minutes. The substrate reaction is stopped by adding 50 pL of 2M H2SO4 stopping solution to each well. The OD value at 450 nm is read using a microplate reader to analyze the binding capacity of the antibody that binds to TL1A. Hybridoma cell lines obtained in whole medium containing serum are expanded and selected. Cells are centrifuged and transferred to serum-free Hybridoma-SFM medium at a density of 1-2 χ¹⁰⁶ cells / ml. They are cultured for one week at 37 °C with 8% CO₂. The culture supernatant is centrifuged to collect. It is purified by protein G affinity chromatography to obtain the human anti-TL1A monoclonal antibody protein. Through screening, 60 hybridoma cell lines were obtained. All antibodies obtained from the hybridoma cell line of the present invention can be produced by genetic engineering methods.

[00109] 1.4 Murine antibody binding capacity to human TL1A-His protein

[00110] An enzyme-linked immunosorbent assay (ELISA) was used to determine the binding capacity of the murine antibody to the human TL1A-His protein. The specific method is as follows:

[00111] The TL1A-His protein was diluted to 1 pg / mL in PBS buffer, with 100 pL per well added to the plate and incubated overnight at 4 °C. The plate was then blocked with 5% skimmed milk powder and incubated at 37 °C for 1 hour; after washing the plate 3 times with PBST, an 11-fold serial dilution of laboratory-prepared anti-human mouse TL1A antibody in 1% BSA-PBS buffer was added, starting with 10 pg / mL. 1% BSA-PBS was used as a blank control. 100 pL per well was added to the pre-coated TL1A-His plate and incubated at 37 °C for one hour; the plate was washed 3 times with PBST. Petition 870250088681, dated 09 / 30 / 2025, page 45 / 90 31 / 53 was treated with HRP-labeled secondary antibody (goat IgG anti-mouse) and incubated at 37 °C for 30 minutes. After washing the plate 3 times with PBST, the residual liquid was dried as much as possible with absorbent paper. 100 μL of TMB was added to each well. At room temperature (20±5 °C) and protected from light for 5 minutes, the substrate reaction was stopped by adding 50 μL of 2 M H2SO4 stopping solution to each well. The optical density (OD) value at 450 nm was read using a microplate reader to analyze the binding capacity of the antibody to human TL1A-His. The data obtained were analyzed using GraphPad Prism 9 software for adjustment. The results are shown in Figures 1A, 1B, 1C. As shown in Figures 1A, 1B, and 1C, most mouse-derived antibodies exhibit excellent binding activity to the target antigen TL1A-His, with EC50 values ​​as detailed in Tables 1-1 to 1-3. Table 1-1 Mouse antibodies 604 B8H8 607 D11B10 607 D12A8 610 B12H2 619 G5G2 620 B12E6 623 D7F3 EC50 58.8 72.08 36.03 41.01 329.4 97.59 27.17 Mouse antibodies 625 F1E10 646 E8H7 653 E3A1 655 G8C1 656 G4A10 701 H2C2 745 H9H9 EC50 103.8 187.3 58.46 20.68 64.62 26.34 50.51 Petition 870250088681, dated 09 / 30 / 2025, page 46 / 90 32 / 53 Table 1-2 Mouse antibodies 620 A6A 5 626 B3G8 627 G6A4 634 F12H 1 642 H9B1 642 G1G9 D3 648 H11 H4 626 H4B1 655 F11H 1 4.36 2.38x 1021 EC50 8x10 15 177.6 85.3 124.7 1779 224.8 906.4 33.11 Mouse antibodies 703 C3G 4 710 E10D 8 710 H2G7 726 H5C8 727 B10D 3 716 D3C6 734 B3D8 728 H4D9 723 D5A 9 EC50 31.2 5 48.11 556.4 22.51 115.8 32.87 415.5 24.92 51.63 Mouse antibodies 727 D5A 5 755 A7B1 0 740 D4E5 758 E4H8 735 C7B2 741 A5B2 734 D5A1 0 737 C12F1 2 731 F12B 7 EC50 24.5 4 36.95 21.91 79.33 270.4 267.2 75.42 462.2 113.7 Table 1-3 Mouse antibodies 601 D12B 11E2 724 G9F11 F11 802 A3G8 805 F9G10 806 D9G11 807 F2F4 810 E6A12 EC50 46.61 97.11 57.69 67.32 12.18 34.94 49.31 Mouse antibodies 823 C9E7 834 F4H1 834 E4E5 835 G2C11 842 B10E3 846 E2H9 850 G9A1 EC50 72.55 64.84 24.17 39.38 335.4 76.58 236.5 Mouse antibodies 335 F12F7 820 B6B7 311 C9E10 814 G9G4 854 A8E2 813 A7C2 853 G9B9 EC50 143.9 71.32 60.54 52.02 71.64 64.39 78.85

[00112] 1.5 Assay of murine antibody blocking activity against TL1A protein binding in stable 293FT-DR3 cell lines

[00113] The present implementation example used fluorescence-activated cell screening (FACS) to determine the antibody's blocking activity against the binding of 293FT-DR3 to the human TL1A protein.

[00114] This experiment used 293FT-DR3 cells (a genetically modified cell line constructed in the laboratory using an expression vector to express high levels of human DR3) as target cells. TL1A was labeled with Alexa Fluor™ 647 NHS Ester reagent (Thermo Fisher). Petition 870250088681, dated 09 / 30 / 2025, page 47 / 90 33 / 53 to conjugate the fluorescent marker 647. 293FT-DR3 cells were counted, washed once with 1% BSA-PBS, and seeded at 2χ¹⁰⁵ cells per well at 100 μl per well. After centrifugation to remove the supernatant, purified mouse anti-DR3 antibody (12 μg / ml) was serially diluted 3 times in 11 gradients using 1% BSA-PBS. A 1% BSA-PBS solution served as a blank control. In each well, 100 μl of antigen were taken and carefully mixed with 20 μl of fluorescent protein TL1A-His-647 (prepared internally, final concentration of 100 ng / ml). Incubated at 37 °C for 30 minutes. Subsequently, 293FT-DR3 cell cultures were removed in 100 μl of the mixture, incubated at 4 °C for 1 hour, washed twice with 1% BSA-PBS, and then removed in 200 μl of PBS. The blocking activity of the mouse antibody against the binding of this cell to the TL1A-his protein was determined by flow cytometry.The data obtained were analyzed using GraphPad Prism 9 software for fitting. The results are shown in Figures 2A, 2B, and 2C. The results indicate that most murine antibodies specifically block the binding between DR3 and the TL1A-his protein on the surface of 293FT cells, with IC50 values ​​as shown in Tables 2-1 to 2-3. Table 2-1 Mouse antibodies 604 B8H8 607 D11B10 607 D12A8 610 B12H2 619 G5G2 620 B12E6 623 D7F3 IC50 436.1 471.1 462.1 437.7 378.7 463.3 140.9 Mouse antibodies 625F1E10 646E8H7 653E3A1 655G8C1 656G4A10 701H2C2 745H9H9 IC50 392.4 917.5 162.5 219.1 460 871.8 436 Petition 870250088681, dated 09 / 30 / 2025, page 48 / 90 34 / 53 Table 2-2 Mouse antibodies 620 A6A5 626 B3G8 627 G6A4 634 F12H 1 642 H9B1 642 G1G 9D3 648 H11H 4 626 H4B 1 655 F11H 1 IC50 149.6 520.4 675.9 683.8 516.6 499. 5 821.1 239. 1 121.9 Mouse antibodies 703C3 G4 710E1 0D8 710H2 G7 726H5 C8 727B1 0D3 716 D3C 6 734B3 D8 728 H4D 9 723D 5A9 IC50 367.4 209.7 742.3 540.8 633.3 422. 9 816.4 445. 3 760.6 Mouse Antibodies 727D5 A5 755A7 B10 740D4 E5 758E4 H8 735C7 B2 741 A5B 2 734D5 A10 737 C12 F12 731F 12B7 IC50 427.1 361.6 419.1 254.5 461 503 430.1 209. 4 554.7 Table 2-3 Mouse antibodies 601 D12B 11E2 724 G9F11 F11 802 A3G8 805 F9G10 806 D9G11 807 F2F4 810 E6A12 IC50 433.8 402.2 353.9 444.2 398.8 435.3 488.9 Mouse antibodies 823 C9E7 834 F4H1 834 E4E5 835 G2C11 842 B10E3 846 E2H9 850 G9A1 IC50 433 298.7 415.3 208.6 1434 460.3 463.4 Mouse antibodies 335 F12F7 820 B6B7 311 C9E10 813 A7C2 853 G9B9 814 G9G4 854 A8E2 IC50 186.1 454.9 179.8 332.9 199.3 501.6 297.6

[00115] Implementation Example 2: Humanization of a murine anti-human TL1A monoclonal antibody a. Determination of the sequence of the variable region of the murine monoclonal antibody anti-human TL1A

[00116] The hybridoma clone 728H4D9, 311C9E10 was selected as the candidate antibody. Total RNA was extracted from the corresponding hybridoma monoclonal cell line using Trizol (purchased from Life Technologies). The mRNA was reverse transcribed into cDNA using a reverse transcription kit (purchased from Takara). PCR was performed using combined primers reported in the literature (Antibody Engineering, Volume 1, edited by Roland Kontermann and Stefan Dübel, with Petition 870250088681, dated 09 / 30 / 2025, page 49 / 90 (35 / 53 primer sequences obtained on page 323). The resulting PCR products were sequenced and analyzed using the Kabat database, confirming the obtained sequences as the variable region sequences of the murine antibody. The 728H4D9 heavy chain variable region gene sequence spans 357 bp in total length, encoding 119 amino acid residues. The nucleotide sequence is shown in SEQ ID No.: 2, and the amino acid sequence is shown in SEQ ID No.: 3; the light chain variable region gene sequence has a total length of 318 bp, encoding 106 amino acid residues. The nucleotide sequence is shown in SEQ ID No.: 4 and the amino acid sequence is shown in SEQ ID No.: 5. The 311C9E10 heavy chain variable region gene sequence spans 357 bp in total length, encoding 119 amino acid residues.The nucleotide sequence is shown in SEQ ID No. 6, and the amino acid sequence is shown in SEQ ID No. 7; the variable region gene sequence of the light chain is 318 bp in total length, encoding 106 amino acid residues. The nucleotide sequence is shown in SEQ ID No. 8 and the amino acid sequence is shown in SEQ ID No. 9.

[00117] ID No. SEQ: 2 GAGGTCCAGCTGCAACAGTCTGGACCTGAGCTGGTGAAGCCTGGAGCTTCAATGAA GATATCCTGCAAGGCTTCTGGTTACTCATTCACTGGCTACACCATGAACTGGGTGA AGCAGAGCCATGGAAAGAACCTTGAGTGGATTGGACTTATTAATCCTTACAGCGGT GGTACTAACTACAACCAGAAGTTCAAGGGCAAGGCCACATTAACTGTAGACAAGAC ATCCAGCACAGCCTACATGGAGCTCCTCAGTCTGACATCTGAGGACTCTGCAGTCT ATTACTGTGCGTCCATCTACCAAAGGCACGACGGGATTGCTTACTGGGGCCAAGGG ACTCTGGTCACTGTCTCTGCA

[00118] ID SEQ N°: 3 Petition 870250088681, dated 09 / 30 / 2025, pp. 50 / 90 36 / 53 EVQLQQSGPELVKPGASMKISCKASGYSFTGYTMNWVKQSHGKNLEWIGLINPYSG GTNYNQKFKGKATLTVDKTSSTAYMELLSLTSEDSAVYCASIYQRHDGIAYWGQG TLVTVSA

[00119] N° SEQ ID: 4 CAAATTGTTCTCACCCAGTCTCCAGCAATCATGTCTGCATCTCCAGGGGAGAAGGT CACCATGACCTGCAGTGCCAGCTCAAGTGTAAATTACATGCACTGGTACCAGCAGA AGTCAGGCACCTCCCCCAAAAGATGGATTTATGACACATCCAAACTGGCTTCTGGA GTCCCAACTCGCTTCAGTGGCAGTGGGTCTGGGACCTCTTACTCTCTCACAATCAG CAGCATGGAGGCTGAAGATGCTGCCACTTATTACTGCCAGCAGTGGAGTAGTAGCC CATACACGTTCGGAGGGGGGACCAAGCTGGAAATCAAA

[00120] No. 5 SEQ ID: QIVLTQSPAIMSASPGEKVTMTCSASSSVNYMHWYQQKSGTSPKRWIYDTSKLASG VPTRFSGSGSGTSYSLTISSMEAEDAATYCQWSSSPYTFGGGTKLEIK

[00121] N° ID SEQ: 6 GAAGTGAAACTTGAGGAGTCTGGAGGAGGCTTAGTGCAACCTGGAGGATCCATGAA ACTCTCCTGTGTTGCCTCTGGATTCACTTTCAGTAACTACTGGATGAACTGGGTCC GCCAGTCTCCAGAGAAGGGGCTTGAGTGGGTTGCTGGAATTAGATTGAAATCTAAT AATTATACAACACAGTATGCGGAGTCTGTGAAAGGGAGGTTCACCATTTCAAGAGA TGATTCCAAAAGTAGTGTCTACCTGCAAATGAACAACTTAAGAGCTGAAGACACTG GCATTTATTATTGTACCCCATTACTCCTCAATGGTATGGACTACTGGGGTCAAGGA ACCTCAGTCACCGTCTCCTCA

[00122] N° ID SEQ: 7 EVKLEESGGGLVQPGGSMKLSCVASGFTFSNYWMNWVRQSPEKGLEWVAGIRLKSN NYTTQYAESVKGRFTISRDDSKSSVYLQMNNLRAEDTGIYYCTPLLLNGMDYWGQG TSVTVSS

[00123] N° ID SEQ: 8 GAAAATGTTCTCACCCAGTCTCCAGCAATCATGTCTGCATCTCCAGGGGAAAAGGT CATCATGACCTGTAGTGCCAGCTCAAGTGTAAGCTACATGCACTGGTACCAGCGGA AGTCAAACACCTCCCCCAAACTCTGGATTTATGACACATCCAATCTGGCTTCTGGA GTCCCAGGTCGCTTCAGTGGCACTGGGTCTGGAAACTCTTACTCTCTCACGATCAG CAGCATGGAGGCTGAAGATGTTGCCACTTATTACTGTTTTCAGGAGAGTGGGTACC CATTCACGTTCGGCTCGGGGACAAAGTTGGAAATAAAA Petição 870250088681, de 30 / 09 / 2025, pág. 51 / 90 37 / 53

[00124] N° ID SEQ: 9 ENVLTQSPAIMSASPGEKVIMTCSASSSVSYMHWYQRKSNTSPKLWIYDTSNLASG VPGRFSGTGSGNSYSLTISSMEAEDVATYYCFQESGYPFTFGSGTKLEIK a. Humanization of the murine anti-TL1A monoclonal antibody

[00125] Analysis of the amino acid sequences in the variable regions of the heavy and light chains of 728H4D9 identified 3 antigenic complementarity-determining regions (CDRs) and 4 frames (FRs) according to Kabat's rules. The amino acid sequences of the complementary determinant regions of the heavy chain are: HCDR1: GYTMN (SEQ ID No.: 10), HCDR2: LINPYSGGTNYNQKFKG (SEQ ID No.: 11) and HCDR3: IYQRHDGIAY (SEQ ID No.: 12). The amino acid sequences of the complementarity-determining region of the light chain are: LCDR1: SASSSVNYMH (Seq ID No: 13), LCDR2: DTSKLAS (Seq ID No: 14) and LCDR3: QQWSSSPYT (Seq ID No: 15).

[00126] By performing homology comparisons in NCBI IgBlast with human IgG germline sequences, IGHV1-2*02 was selected as a heavy chain CDR graft template, and IGKV6-21*01 as a light chain CDR graft template. The CDR regions of the 728H4D9 antibody were grafted onto the selected humanized templates, replacing the CDR regions of the human templates. The variable region of the heavy chain (amino acid sequence shown in SEQ ID No.: 33) was then recombined with the human IgG1 constant region, while the variable region of the light chain (amino acid sequence shown in SEQ ID No.: 34) was recombined with the human kappa constant region. In parallel, based on the three-dimensional structure of this antibody, reverse mutations were introduced in residues that directly interact with the CDR regions and in residues that significantly influence the conformation of the antibody's VL and VH chains. Thus, multiple humanized antibodies were generated.Through affinity screening, they were... Petition 870250088681, dated 09 / 30 / 2025, page 52 / 90 38 / 53 identified multiple humanized antibodies, residues that interact directly with the CDR regions, and those that significantly influence the VL and VH conformation of the antibody. Multiple humanized antibodies were obtained and, through affinity screening, the amino acid sequence of the variable region of the heavy chain (SEQ ID No.: 16) and the amino acid sequence of the variable region of the light chain (SEQ ID No.: 17) of humanized antibody 72851 were determined. Their nucleotide sequences are presented as SEQ ID No.: 35 and SEQ ID No.: 36, respectively.

[00127] SEQ ID No.: 16 QVQLVQSGAEVKKPGASVKVSCKASGYSFTGYTMNWVRQAPGQNLEWIGLINPYSG GTNYNQKFKGRATLTVDTSISTAYMELSRLRSDDTAVYYCASIYQRHDGIAYWGQG TLVTVSS

[00128] SEQ ID No.: 17 EIVLTQSPDFQSVTPKEKVTITCSASSSVNYMHWYQQKPDQSPKLLIKDTSKLASG VPSRFSGSGSGTDFTLTINSLEAEDAATYYCQWSSSPYTFGGGTKVEIK

[00129] No. SEQ ID: 33 ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPPVTVSWNSGALTSGVHTFPAV LQSSGLYSLSSVVTVPSSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPC PAPEAAGGPSVFLFPPKPKDTLYITREPEVTCVVVVDVSHPEVVVGVHVGVH NAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNCALPAPIECTISKAKG QPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPV LDSDGSFFLYSKLTVDKSRWQQGNVFSVMHEHQSLKHQSLKHQ

[00130] No. SEQ ID: 34 RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESV TEQDSKDSTYSLSSTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC

[00131] N° ID SEQ: 35 CAAGTGCAGCTGGTGCAGAGCGGCGCCGGTGAAGAAGCCTGGCGCTAGCGTGAA GGTGAGCTGCAAGGCTAGCGGCTACAGCTTCACCGGCTACACCATGAACTGGGTGA GACAAGCCCCTGGACAGAACCTGGAGTGGATCGGCCTGATCAACCCTTACAGCGGC GGAACCAACTACAATCAGAAGTTCAAGGGCAGAGCCACACTGACCGTGGACACAAG Petition 870250088681, of 30 / 09 / 2025, p. 53 / 90 39 / 53 CATCAGCACCGCCTACATGGAGCTGAGCAGACTGAGAAGCGACGACACCGCCGTGT ATTATTGCGCCTCCATCTATCAGAGACACGACGGCATCGCCTACTGGGGCCAAGGC ACCCTGGTGACCGTGAGCAGC

[00132] N° ID SEQ: 36 GAGATCGTGCTGACACAGAGCCCTGACTTTCAGAGCGTGACCCCTAAGGAGAAGGT GACCATTACCTGCAGCGCTAGCAGCAGCGTGAACTACATGCACTGGTATCAGCAGA AGCCTGATCAGAGCCCTAAGCTGCTGATCAAGGACACAAGCAAGCTGGCTAGCGGC GTGCCTAGCAGATTCAGCGGCAGCGGCAGCGGCACCGACTTCACCCTGACCATCAA CAGCCTGGAGGCCGAGGACGCCGCCACCTACTACTGTCAGCAGTGGAGCAGCAGCC CTTACACCTTCGGCGGAGGCACCAAGGTGGAGATCAAA

[00133] Analysis of amino acid sequences in the variable regions of the heavy and light chains of 311C9E10 identified 3 antigenic complementarity-determining regions (ACRs) and 4 frames (FRs) according to Kabat's rules. The amino acid sequences of the complementary determinant regions of the heavy chain are: ACR1: NYWMN (SEQ ID No.: 18), ACR2: GIRLKSNNYTTQYAESVKG (SEQ ID No.: 19), and ACR3: LLLNGMDY (SEQ ID No.: 20). The amino acid sequences of the complementarity-determining regions of the light chain are: ACR1: SASSSVSYMH (SEQ ID No.: 21), ACR2: DTSNLAS (SEQ ID No.: 22), and ACR3: FQESGYPFT (SEQ ID No.: 23).

[00134] By performing homology comparisons in NCBI IgBlast with human IgG germline sequences, IGHV3-73*01 was selected as a heavy chain CDR graft template, and IGKV6-21*01 as a light chain CDR graft template. The CDR regions of the 311C9E10 antibody were grafted onto the selected humanized templates, replacing the CDR regions of the human templates. The variable region of the heavy chain (amino acid sequence shown in SEQ ID No.: 33) was then recombined with the human IgG1 constant region, while the variable region of the light chain (amino acid sequence shown in SEQ ID No.: 34) was recombined with the human kappa constant region. Petition 870250088681, dated 09 / 30 / 2025, pp. 54 / 90 40 / 53 In parallel, based on the three-dimensional structure of this antibody, reverse mutations were introduced in residues that interact directly with the CDR regions and in residues that significantly influence the conformation of the antibody's VL and VH chains. Thus, multiple humanized antibodies were generated. Through affinity screening, multiple humanized antibodies, residues that interact directly with the CDR regions, and those that significantly influence the conformation of the antibody's VL and VH chains were identified. Multiple humanized antibodies were obtained and, through affinity screening, the sequence of the variable region of the heavy chain (SEQ ID No.: 24) and the sequence of the variable region of the light chain (SEQ ID No.: 25) of the humanized antibody 31122 were determined. Their nucleotide sequences are presented as SEQ ID No.: 37 and SEQ ID No.: 38, respectively.

[00135] SEQ ID No.: 24 EVQLVESGGGLVQPGGSLKLSCAASGFTFSNYWMNWVRQASGKGLEWVGGIRLKSN NYTTQYAESVKGRFTISRDDSKNTAYLQMNSLCTEDTAVYYCTPLLLNGMDYWGQG TTVTVSS

[00136] N° SEQ ID: 25 EIVLTQSPDFQSVTPKEKVTITCSASSSVSYMHWYQQKPDQSPKLWIYDTSNLASG VPSRFSGSGSGTDFTLTINSLEAEDAATYCFQESGYPFTFGQGTKLEIK

[00137] No. ID SEQ: 37 GAGGTGCAGCTGGTCGAGTCCGGAGGCGGACTGGTCCCAACCTGGCGGAAGCCCTGAA GCTGAGCTGCGCCGCTAGCGGCTTCACCTTCAGCAACTACTGGATGAACTGGGTGA GACAAGCTAGCGGCAAGGGCCTGGAGTGGGTGGGCGGCATCAGACTGAAGAGCAAC AACTACACCACACAGTACGCCGAGAGCGTGAAGGGCAGATTCACCATCAGCAGAGA CGACAGCAAGAACACCGCCTACCTGCAGATGAACAGCCCTGAAGACCGAGGACACCG CCGTGTACTACTGCACACCTCTGCTCCTGAACGGCATGGACTACTGGGGCCAAGGC ACCACCGTGACCGGACCGGC

[00138] No. SEQ ID: 38 Petition 870250088681, of 30 / 09 / 2025, p. 55 / 90 41 / 53 GAGATCGTGCTGACACAGAGCCCTGACTTTCAGAGCGTGACCCCTAAGGAGAAGGT GACCATCACCTGCAGCGCTAGCAGCAGCGTGAGCTACATGCACTGGTATCAGCAGA AGCCTGATCAGAGCCCTAAGCTGTGGATCTACGACACAAGCAACCTGGCTAGCGGC GTGCCTAGCAGATTCAGCGGCAGCGGCAGCGGCACCGACTTCACCCTGACCATCAA CAGCCTGGAGGCCGAGGACGCCGCCACCTACTACTGCTTCCAAGAGAGCGGCTACC CTTTCACCTTCGGCCAAGGCACCAAGCTGGAGATCAAA

[00139] Implementation Example 3: Determination of the affinity dissociation constant KD for humanized antibody

[00140] Using the Biacore 8K molecular interaction analyzer, the kinetic capture parameters for the dissociation of the humanized antibody candidate 72851 and the humanized antibody candidate 31122, along with the positive control antibody PRA023 and the TL1A-his antigen, were determined. The antibodies were diluted to 2 μg / ml in HBS-EP+ buffer, pH 7.4, and captured on a protein A chip. The antigen was diluted in HBS-EP+ buffer, pH 7.4, and 6 concentration gradients up to 50 nM were prepared for antibody binding. Dissociation was measured in HBS-EP+ buffer, pH 7.4. The experimental results are shown in Table 3, demonstrating that the humanized antibody candidates 72851 and 31122 exhibit superior affinity for TLIA-his compared to the positive control antibody PRA023. Table 3: Affinity dissociation constants Mobile phase Stationary phase KD (M) ka (1 / Ms) kd (1 / s) TL1A-his 72851 2.12E-10 1.00E+06 2.12E-04 TL1A-his 31122 3.94E-10 4.05E+05 1.59E-04 TLIA-his PRA023 5.37E-10 3.08E+05 1.66E-04

[00141] Note: KD denotes affinity constant; ka denotes binding rate constant; kd denotes dissociation rate constant. Petition 870250088681, dated 09 / 30 / 2025, p. 56 / 90 42 / 53

[00142] Implementation Example 4: Optimization of the Physicochemical Properties of the Humanized Antibody 31122

[00143] Due to the high glycosylated modification and charge heterogeneity of the humanized antibody 31122, a mutant library was constructed by introducing single-point saturation mutations at potential glycosylation sites and deamidation sites in the CDR sequences of the variable regions of the heavy chain, along with multiple stacked advantageous mutations (with the constant regions of the light and heavy chains unchanged). Through ELISA affinity assays and capillary isoelectric focusing, candidate antibodies exhibiting superior affinity and charge heterogeneity compared to the parental antibody 31122 were selected.

[00144] The CDR sequences of the variable regions of the heavy chain for each modified candidate antibody are shown in Table 4. Table 4: CDR amino acid sequence HCDR1 HCDR2 HCDR3 311V25 NYWMN (N° ID SEQ: 18) GIRLKSNNYATQYAESVKG (N° ID SEQ: 39) LLLNGMDY (N° ID SEQ: 20) 311V31 NYWMN (N° ID SEQ: 18) GIRLKSNNYKTQYAESVKG (N° ID SEQ: 40) LLLNGMDY (N° ID SEQ: 20) 311V34 NYWMN (N° ID SEQ: 18) GIRLKSNNYRTQYAESVKG (N° ID SEQ: 41) LLLNGMDY (N° ID SEQ: 20) 311V25-7 NYWMN (N° ID SEQ: 18) GIRLKSNNYATQYAESVKG (N° ID SEQ: 39) LLLSGMDY (N° ID SEQ: 42) 311V31-7 NYWMN (N° ID SEQ: 18) GIRLKSNNYKTQYAESVKG (N° ID SEQ: 40) LLLSGMDY (N° ID SEQ: 42) 311V34-7 NYWMN (N° ID SEQ: 18) GIRLKSNNYRTQYAESVKG (N° ID SEQ: 41) LLLSGMDY (N° ID SEQ: 42) 00145

[00146] 311V25-HC (N° ID SEQ: 26) Petition: 870250088681, on September 30, 2025, page. 57 / 90 43 / 53 EVQLVESGGGLVQPGGSLKLSCAASGFTFSNYWMNWVRQASGKGLEWVGGIRLKSN NYATQYAESVKGRFTISRDDSKNTAYLQMNSLKTEDTAVYYCTPLLLNGMDYWGQG TTVTVSS

[00147] 311V31-HC (N° ID SEQ: 27) EVQLVESGGGLVQPGGSLKLSCAASGFTFSNYWMNWVRQASGKGLEWVGGIRLKSN NYKTQYAESVKGRFTISRDDSKNTAYLQMNSLKTEDTAVYYCTPLLLNGMDYWGQG TTVTVSS

[00148] 311V34-HC (N° ID SEQ: 28) EVQLVESGGGLVQPGGSLKLSCAASGFTFSNYWMNWVRQASGKGLEWVGGIRLKSN NYRTQYAESVKGRFTISRDDSKNTAYLQMNSLKTEDTAVYYCTPLLLNGMDYWGQG TTVTVSS

[00149] 311V25-7-HC (N° ID SEQ: 29) EVQLVESGGGLVQPGGSLKLSCAASGFTFSNYWMNWVRQASGKGLEWVGGIRLKSN NYATQYAESVKGRFTISRDDSKNTAYLQMNSLKTEDTAVYYCTPLLLSGMDYWGQG TTVTVSS

[00150] 311V31-7-HC (N° ID SEQ: 30) EVQLVESGGGLVQPGGSLKLSCAASGFTFSNYWMNWVRQASGKGLEWVGGIRLKSN NYKTQYAESVKGRFTISRDDSKNTAYLQMNSLKTEDTAVYYCTPLLLSGMDYWGQG TTVTVSS

[00151] 311V34-7-HC (N° ID SEQ: 31) EVQLVESGGGLVQPGGSLKLSCAASGFTFSNYWMNWVRQASGKGLEWVGGIRLKSN NYRTQYAESVKGRFTISRDDSKNTAYLQMNSLKTEDTAVYYCTPLLLSGMDYWGQG TTVTVSS

[00152] N° ID SEQ: 43 GAGGTGCAGCTGGTCGAGTCCGGAGGCGGACTGGTCCAACCTGGCGGAAGCCTGAA GCTGAGCTGCGCCGCTAGCGGCTTCACCTTCAGCAACTACTGGATGAACTGGGTGA GACAAGCTAGCGGCAAGGGCCTGGAGTGGGTGGGCGGCATCAGACTGAAGAGCAAC AACTACGCCACACAGTACGCCGAGAGCGTGAAGGGCAGATTCACCATCAGCAGAGA CGACAGCAAGAACACCGCCTACCTGCAGATGAACAGCCTGAAGACCGAGGACACCG CCGTGTACTACTGCACACCTCTGCTCCTGAACGGCATGGACTACTGGGGCCAAGGC ACCACCGTGACCGTGAGCAGC

[00153] N° ID SEQ: 44 Petição 870250088681, de 30 / 09 / 2025, pág. 58 / 90 44 / 53 GAGGTGCAGCTGGTCGAGTCCGGAGGCGGACTGGTCCAACCTGGCGGAAGCCTGAA GCTGAGCTGCGCCGCTAGCGGCTTCACCTTCAGCAACTACTGGATGAACTGGGTGA GACAAGCTAGCGGCAAGGGCCTGGAGTGGGTGGGCGGCATCAGACTGAAGAGCAAC AACTACAAGACACAGTACGCCGAGAGCGTGAAGGGCAGATTCACCATCAGCAGAGA CGACAGCAAGAACACCGCCTACCTGCAGATGAACAGCCTGAAGACCGAGGACACCG CCGTGTACTACTGCACACCTCTGCTCCTGAACGGCATGGACTACTGGGGCCAAGGC ACCACCGTGACCGTGAGCAGC

[00154] N° ID SEQ: 45 GAGGTGCAGCTGGTCGAGTCCGGAGGCGGACTGGTCCAACCTGGCGGAAGCCTGAA GCTGAGCTGCGCCGCTAGCGGCTTCACCTTCAGCAACTACTGGATGAACTGGGTGA GACAAGCTAGCGGCAAGGGCCTGGAGTGGGTGGGCGGCATCAGACTGAAGAGCAAC AACTACAGAACACAGTACGCCGAGAGCGTGAAGGGCAGATTCACCATCAGCAGAGA CGACAGCAAGAACACCGCCTACCTGCAGATGAACAGCCTGAAGACCGAGGACACCG CCGTGTACTACTGCACACCTCTGCTCCTGAACGGCATGGACTACTGGGGCCAAGGC ACCACCGTGACCGTGAGCAGC

[00155] N° ID SEQ: 46 GAGGTGCAGCTGGTCGAGTCCGGAGGCGGACTGGTCCAACCTGGCGGAAGCCTGAA GCTGAGCTGCGCCGCTAGCGGCTTCACCTTCAGCAACTACTGGATGAACTGGGTGA GACAAGCTAGCGGCAAGGGCCTGGAGTGGGTGGGCGGCATCAGACTGAAGAGCAAC AACTACGCCACACAGTACGCCGAGAGCGTGAAGGGCAGATTCACCATCAGCAGAGA CGACAGCAAGAACACCGCCTACCTGCAGATGAACAGCCTGAAGACCGAGGACACCG CCGTGTACTACTGCACACCTCTGCTCCTGAGCGGCATGGACTACTGGGGCCAAGGC ACCACCGTGACCGTGAGCAGC

[00156] N° ID SEQ: 47 GAGGTGCAGCTGGTCGAGTCCGGAGGCGGACTGGTCCAACCTGGCGGAAGCCTGAA GCTGAGCTGCGCCGCTAGCGGCTTCACCTTCAGCAACTACTGGATGAACTGGGTGA GACAAGCTAGCGGCAAGGGCCTGGAGTGGGTGGGCGGCATCAGACTGAAGAGCAAC AACTACAAGACACAGTACGCCGAGAGCGTGAAGGGCAGATTCACCATCAGCAGAGA CGACAGCAAGAACACCGCCTACCTGCAGATGAACAGCCTGAAGACCGAGGACACCG CCGTGTACTACTGCACACCTCTGCTCCTGAGCGGCATGGACTACTGGGGCCAAGGC ACCACCGTGACCGTGAGCAGC

[00157] N° ID SEQ: 48 Petição 870250088681, de 30 / 09 / 2025, pág. 59 / 90 45 / 53 GAGGTGCAGCTGGTCGAGTCCGGAGGCGGACTGGTCCAACCTGGCGGAAGCCTGAA GCTGAGCTGCGCCGCTAGCGGCTTCACCTTCAGCAACTACTGGATGAACTGGGTGA GACAAGCTAGCGGCAAGGGCCTGGAGTGGGTGGGCGGCATCAGACTGAAGAGCAAC AACTACAGAACACAGTACGCCGAGAGCGTGAAGGGCAGATTCACCATCAGCAGAGA CGACAGCAAGAACACCGCCTACCTGCAGATGAACAGCCTGAAGACCGAGGACACCG CCGTGTACTACTGCACACCTCTGCTCCTGAGCGGCATGGACTACTGGGGCCAAGGC ACCACCGTGACCGTGAGCAGC

[00158] The experimental results of the ELISA are presented in Figure 3A, demonstrating that the candidate antibodies 72851, 31122, 311V25, 311V31, 311V34, 311V25-7, 311V31-7 and 311V34-7 exhibit superior binding affinity to the TL1A-his antigen compared to the positive control PRA023.

[00159] The results of capillary isoelectric focusing for candidate anti-TL1A antibodies are shown in Figure 3B. The experimental results indicate that the modified antibody 311V25-7 and the modified antibody 311V31-7 exhibit superior charge heterogeneity compared to their parent antibody 31122, comparable to the candidate antibody 72851.

[00160] Implementation Example 5: Experiment inhibiting TL1A-DR3 binding with anti-TL1A antibody

[00161] This implementation example used fluorescence-activated cell screening (FACS) to evaluate the effectiveness of anti-TL1A antibody blocking against the interaction between TL1A and its cell surface receptor DR3. The target cells used were 293FT-DR3 cells, a modified cell line expressing high levels of human DR3, constructed in our laboratory. The DR3 sequence used as an antigen was obtained from the UniProt database (Entry: Q93038), with the amino acid sequence shown in SEQ ID No.: 32.

[00162] SEQ ID No.: 32 Petition 870250088681, dated 09 / 30 / 2025, pages 60 / 90 46 / 53 MEQRPRGCAAVAAALLLVLLGARAQGGTRSPRCDCAGDFHKKIGLFCCRGCPAGHY LKAPCTEPCGNSTCLVCPQDTFLAWENHHNSECARCQACDEQASQVALENCSAVAD TRCGCKPGWFVECQVSQCVSSSPFYCQPCLDCGALHRHTRLLCSRRDTDCGTCLPG FYEHGDGCVSCPTSTLGSCPERCAAVCGWRQMFWVQVLLAGLVVPLLLGATLTYTY RHCWPHKPLVTADEAGMEALTPPPATHLSPLDSAHTLLAPPDSSEKICTVQLVGNS WTPGYPETQEALCPQVTWSWDQLPSRALGPAAAPTLSPESPAGSPAMMLQPGPQLY DVMDAVPARRWKEFVRTLGLREAEIEAVEVEIGRFRDQQYEMLKRWRQQQPAGLGA VYAALERMGLDGCVEDLRSRLQRGP

[00163] The TL1A-his antigen is conjugated with Alexa Fluor™ 647 fluorescent dye (purchased from Invitrogen, catalog number A20006) and reserved. The fluorescently labeled antigen, TL1A-his-647, is diluted to a concentration of 200 ng / ml using 1% BSA-PBS; the anti-TL1A antibody should be diluted to 200 nM in 1% BSA-PBS. Four dilutions are performed to create eight concentration gradients. 200 ng / ml of TL1A-His-647 was added to the antibody at different concentrations, incubated at 4°C for 1 hour, and then added to 293FT-DR3 cell plates (1x10⁵ cells / well) containing cell wash supernatant. The cells were incubated at 4 °C for 1 hour and then washed twice with PBS to remove unbound antigen. Finally, the cells were resuspended in 200 μE of PBS. The mean fluorescence intensity was measured by flow cytometry, and the data obtained were analyzed using GraphPad Prism 9 software.The results are shown in Figure 4. Experimental results indicate that candidate antibodies 72851, 31122, 311V25, 311V31, 311V34, 311V25-7, 311V31-7, 311V34-7 and the positive control antibody PRA023 block TL1A binding to DR3, with the candidate antibodies exhibiting superior blocking capacity compared to PRA023.

[00164] Implementation example 6: The anti-TL1A antibody inhibits the activation of NF-kB by TL1A Petition 870250088681, dated 09 / 30 / 2025, pp. 61 / 90 47 / 53

[00165] After binding to its DR3 receptor, TL1A activates the intracellular NF-κB signaling pathway and triggers apoptosis. The present implementation example used a TF-1 cell line that stably expresses luciferase under NF-κB regulation (TF-1-NF-κB-Luc cells) to evaluate the inhibition of anti-TL1A antibody of TL1A-induced NF-κB pathway activation.

[00166] TL1A-his protein is diluted in RPMI 1640 + 10% FBS medium to 800 ng / mL (final concentration 200 ng / mL) and then 25 μL is added to each well of a 96-well flat-bottom plate. Anti-TL1A antibody is diluted to 200 nM in RPMI 1640 medium + 10% FBS, creating an 8-point concentration gradient through double dilutions. 25 μL is added to each well containing TL1A-his, maintaining a final antibody concentration of 50 nM throughout the process. The sample is centrifuged, and TF-1-NF-kB-Luc cells are counted.Cell density is adjusted, and 50 μL per well (1 χ¹⁰⁵ cells / well) is added to the 96-well plate, incubating at 37 °C for 24 hours. The following day, the cell plates should be removed and allowed to equilibrate at room temperature for approximately 15 minutes. 100 μL of Bio-Lite Luciferase (acquired from Novazeen Biotechnology Co., Ltd., Nanjing, China; Catalog No.: DD1201-02) is added to each well. After 10 minutes, the emitted light is measured in RLU (Relative Light Unit) using a microplate reader. Data analysis was performed using GraphPad Prism9 software, with plotting and IC50 calculation. The results are shown in Figure 5. Experimental results indicate that the candidate antibodies 72851, 311V25-7, 311V31-7 and the positive control antibody PRA023 effectively inhibit NF-κB activated by TL1A. The inhibitory potency of the candidate antibodies surpasses that of the positive control antibody PRA023.

[00167] Implementation example 7: The anti-TL1A antibody Petition 870250088681, dated 09 / 30 / 2025, pp. 62 / 90 48 / 53 inhibits TL1A-induced apoptosis in TF-1 cells.

[00168] TL1A is an effective and specific inhibitor of endothelial cell growth, inducing apoptosis through binding to DR3. The present implementation example used fluorescence-activated cell screening (FACS) to determine the inhibition of TL1A-induced TF-1 cell apoptosis by anti-TL1A antibody.

[00169] TF-1 cells were centrifuged and counted, then adjusted to an appropriate density for plating in 3599 cell plates at 1 χ¹⁰⁵ cells per well, with 100 μE per well. TL1A-his was diluted to 800 ng / mL in 1640 medium (containing 10% FBS and 1% PS). In parallel, cyclohexylimide (CHX, acquired from CST, Catalog No.: 2112) was added to a final concentration of 40 μg / mL. After thorough mixing, 50 μE was added to each well of the aforementioned 3599 cell plate. The positive control antibody PRA023 and other humanized TL1A antibodies should be diluted in culture medium to 800 nM and then serially diluted 3 times to produce nine concentration gradients. 50 μE of each dilution is added to the 3599 cell plate mentioned above. The final concentration of TL1A-his was 200 ng / mL, the final concentration of CHX was 10 μg / mL, and the final concentration of TL1A antibody was 200 nM.The cell plate should be gently shaken to mix well and placed in an incubator at 37°C. After 6 hours, remove the cell plates, centrifuge at 500 g for 5 minutes, discard the supernatant, wash twice with 1% BSA-PBS, and then use the Annexin V-FITC / PI Apoptosis Assay Kit (purchased from Yeasen Biotechnology (Shanghai) Co., Ltd., Catalog No.: 40302ES60). Then, resuspend the cells in 1χ binding buffer at 100 μE per well. Add 5 μE of Annexin V-FITC and 10 μE of PI staining solution to each well. After 10 to 15 minutes of incubation at temperature. Petition 870250088681, dated 09 / 30 / 2025, pp. 63 / 90 49 / 53 dark environment, mixes well. The cells are then analyzed by flow cytometry. The data were analyzed using GraphPad Prism 9, plotting graphs and calculating EC50. The results are shown in Figure 6. Experimental results indicate that the candidate antibodies 311V25-7, 311V31-7, 311V34-7 and the positive control antibody PRA023 inhibit TL1A-induced apoptosis in TF-1 cells, with the candidate antibodies exhibiting superior inhibitory capacity compared to the positive control antibody PRA023.

[00170] Implementation Example 8: Inhibition of IFNγ secretion by TL1A-stimulated cells via anti-TL1A antibodies

[00171] TL1A exerts its IFN-γ secretion-stimulating effect by binding to DR3. The present implementation example evaluated the activity of anti-TL1A antibody in inhibiting TL1A-induced IFN-γ secretion from PBMCs.

[00172] PBMCs were diluted in RPMI 1640 medium supplemented with 10% FBS, adjusted to a cell density of 3 χ 106 / cells / ml, and 100 µl of cell suspension were added to each well. TL1A-his was diluted to 400 ng / ml in culture medium and the antibody was diluted to 200 nM. A triple gradient dilution was performed. TL1A-his and the antibody were mixed in a 1:1 volume ratio. After incubation at room temperature for 30 minutes, 50 µl of the mixture were added to each well of the PBMC plate. Recombinant IL-12 protein was diluted to 4 ng / ml in medium (25 µl per well) and recombinant IL-18 protein was diluted to 40 ng / ml (25 µl per well). Both were added to cell plates, incubated at 37 °C in a 5% CO2 incubator for 48 hours, after which the cell supernatants were collected. The expression of human IFN-γ in the supernatants was then measured. The experimental results are shown in Figure 7. Petition 870250088681, dated 09 / 30 / 2025, pp. 64 / 90 50 / 53 experimental results indicate that antibodies 72851, 311V25-7, 311V34-7 and the positive control antibody PRA023 inhibit IFN-γ secretion by PBMCs, with the candidate antibodies exhibiting superior inhibitory activity compared to the positive control PRA023.

[00173] Implementation Example 9: Inhibition of TNF-α secretion by anti-TL1A antibody

[00174] As a Th1 polarizing factor, TL1A stimulates Th1 cells to secrete the cytokines IFN-γ and TNF-α, potentially playing a crucial role in the pathogenesis of inflammatory bowel disease (IBD). The present implementation example evaluated the activity of anti-TL1A antibody in inhibiting TL1A-induced TNF-α secretion from PBMCs.

[00175] PBMCs were diluted in RPMI 1640 medium supplemented with 10% FBS, adjusted to a cell density of 3 χ¹⁰⁶ / cells / ml, and 100 µl of cell suspension were added to each well. TL1A-his was diluted to 400 ng / ml in culture medium and the antibody was diluted to 200 nM, 80 nM. A triple gradient dilution was performed. TL1A-his and the antibody were mixed in a 1:1 volume ratio. After incubation at room temperature for 30 minutes, 50 µl of the mixture were added to each well of the PBMC plate. Recombinant IL23 protein was diluted to 400 ng / ml in medium (25 µl per well) and recombinant IL2 protein was diluted to 80 U / ml (25 µl per well). Both were added to cell plates, incubated at 37 °C in a 5% CO2 incubator for 72 hours, after which the cell supernatants were collected. The expression of human TNF-α in the supernatants was then measured. The experimental results are shown in Figure 8.Experimental results indicate that antibodies 72851, 311V25-7, 311V34-7 and the positive control antibody PRA023. Petition 870250088681, dated 09 / 30 / 2025, pages 65 / 90 51 / 53 inhibit TNF-α secretion by PBMCs, with the candidate antibodies exhibiting superior inhibitory activity compared to the positive control PRA023.

[00176] Implementation Example 10: Efficacy study of anti-TL1A antibody in a DSS-induced chronic inflammatory bowel disease model in mice

[00177] DSS was dissolved in the drinking water of mice. The highly negatively charged sulfate groups disrupted the integrity of the intestinal mucosal barrier, inducing an inflammatory response. The animals exhibited marked weight loss, loose stools, bloody stools, and granulocyte infiltration. The clinical symptoms and pathological features were very similar to those observed in human ulcerative colitis. The anti-TL1A antibody candidate molecule 72851 exhibits binding activity comparable to human TL1A homologous proteins (human-TL1A), macaque cynomolgus (Rhesus)-TL1A, and mouse homologous proteins (Rat-TL1A) (experimental ELISA results shown in Figure 9A). Consequently, a mouse model of DSS-induced chronic inflammatory bowel disease was used for in vivo efficacy studies.

[00178] The experiment comprised 3 groups: a blank control group, a model group, and a 72851 treatment group. The blank control group received normal drinking water. The model group and the 72851 treatment group received drinking water containing 5% DSS for 5 days a week, followed by drinking water for 2 days, completing a 7-day cycle. The experiment continued for 4 cycles. The 72851 dosage was 5 mg / kg, administered on alternate days. At the conclusion of the experiment, the animals were anesthetized for blood collection. Serum was collected and, after euthanasia, the entire intestinal tract, from the cecum to the distal rectum, was dissected for measurement. Petition 870250088681, dated 09 / 30 / 2025, pp. 66 / 90 52 / 53 of the length. The spleen was removed and weighed. Serum levels of IL-6 and IL-1β were quantified by ELISA.

[00179] Experimental results demonstrated that, compared to the model group (5% DSS), antibody 72851 effectively suppressed weight loss (as shown in Figure 9B) and colon shortening (as shown in Figure 9C) in the group treated with 72851 (5% DSS + 72851). It also effectively inhibited the elevation of the inflammatory cytokines IL-6 and IL-γβ in mice (as shown in Figures 9D and 9E).

[00180] Implementation Example 11: Efficacy study of anti-TL1A antibody in a TNBS-induced acute inflammatory bowel disease model in mice

[00181] TNBS, a small molecule hapten, induces host protein binding via rectal instillation, triggering a body that causes transmural necrosis and extensive inflammatory cell infiltration in the colon. This is accompanied by weight loss and intestinal obstruction, making it a commonly used agent to model acute enteritis in animals that mimics clinical Crohn's disease. In this model, we validated the therapeutic efficacy of the anti-TL1A 72851 antibody in the treatment of acute enteritis in mice and compared it with Roche's RVT-3101.

[00182] The experiment comprised 4 groups: blank control, model, RVT-3101 treatment, and 72851 treatment. Animals were fasted for 18 hours prior to the experiment. RVT-3101 and 72851 were administered at a dose of 5 mg / kg prior to modeling. Subsequently, animals in the model group, the RVT-3101 treatment group, and the 72851 treatment group were anesthetized. Under anesthesia, 400 µl of a 1.5% TNBS ethanol solution (50% ethanol) were instilled into the colon through the anus using a plastic catheter. Mice were kept in an inverted position. Petition 870250088681, dated 09 / 30 / 2025, pp. 67 / 90 53 / 53 for 3 minutes to prevent leakage of the instilled solution. The animals' condition was monitored throughout anesthesia. After recovery, the animals were returned to their cages for free access to food and water. RVT-3101 and 72851 were administered by intraperitoneal injection on alternate days; the model group received PBS injections on alternate days, with all doses administered at 5 ml / kg. On day 7 of the experiment, the animals were anesthetized, bled, and sacrificed. The entire intestinal tract, from the cecum to the distal rectum, was excised for length measurement, and the spleen was removed for weighing.

[00183] Experimental results demonstrated that, compared to the model group (1.5% TNBS), antibody 72851 effectively inhibited colon shortening (as shown in Figure 10A) and spleen weight increase (as shown in Figure 10B) in the 72851 treatment group (1.5% TNBS + 72581), demonstrating superior efficacy to the RVT-3101 positive control treatment group (1.5% TNBS + RVT-3101).

[00184] The above implementation examples are intended to illustrate disclosed implementations of the present invention and should not be interpreted as limiting the scope of the present invention. Furthermore, various modifications and variations of the methods described herein will be apparent to those skilled in the art, without departing from the scope and spirit of the present invention. Although the present invention has been described in detail with reference to several specific implementation examples and a preferred selection example of the present invention, it should be understood that the present invention is not limited to these specific implementation examples. In fact, various modifications mentioned that are perceptible to those skilled in the art to achieve the present invention should be understood within the scope of the present invention. Petition 870250088681, dated 09 / 30 / 2025, pages 68 / 90

Claims

1 / 11 CLAIMS 1. Anti-TL1A antibody or antigen-binding fragment thereof, characterized in that said anti-TL1A antibody or antigen-binding fragment thereof comprises a variable heavy chain region and a variable light chain region, wherein said anti-TL1A antibody or antigen-binding fragment thereof possesses one or more of the following technical characteristics: <1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in SEQ ID No.: 10 or 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in SEQ ID No.: 11, 19, 39, 40 or 41; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in SEQ ID No.: 12, 20 or 42; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1,as shown in No. ID SEQ: 13 or 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in No. ID SEQ: 14 or 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in No. ID SEQ: 15 or 23.

2. Said anti-TL1A antibody or antigen-binding fragment thereof, according to claim 1, characterized in that the anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Petition 870250088681, dated 09 / 30 / 2025, p. 69 / 90 2 / 11 in No. ID SEQ: 10; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 11; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3,as shown in No. ID SEQ: 12; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in No. ID SEQ: 13; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in No. ID SEQ: 14; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in No. ID SEQ: 15; and / or, the said anti-TL1A antibody comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in No. ID SEQ: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in any of No. ID SEQ: 19, 39, 40, 41; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Sequence ID No.: 20 or 42; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1,as shown in No. ID SEQ: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in No. ID SEQ: 22; Petition 870250088681, dated 09 / 30 / 2025, page 70 / 90 3 / 11 < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in No. ID SEQ:

23.

3. Said anti-TL1A antibody or antigen-binding fragment thereof, according to any one of claims 1 or 2, characterized in that the anti-TL1A antibody or antigen-binding fragment thereof further comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in No. ID SEQ: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 19; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3,as shown in No. ID SEQ: 20; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in No. ID SEQ: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in No. ID SEQ: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in No. ID SEQ: 23; and / or, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in No. ID SEQ: 18; < 2> The variable region of the heavy chain comprises a Petition 870250088681, dated 09 / 30 / 2025, p. 71 / 90 4 / 11 amino acid sequence such as HCDR2, as shown in Sequence ID No.: 39; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3,as shown in No. ID SEQ: 20; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in No. ID SEQ: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in No. ID SEQ: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in No. ID SEQ: 23; and / or, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in No. ID SEQ: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in No. ID SEQ: 40; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3,as shown in No. ID SEQ: 20; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in No. ID SEQ: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in No. ID SEQ: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in No. ID SEQ: 23; and / or, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in No. ID SEQ: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 41; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3,as shown in No. ID SEQ: 20; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in No. ID SEQ: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in No. ID SEQ: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in No. ID SEQ: 23; and / or, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in No. ID SEQ: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in No. ID SEQ: 39; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3, as shown in Petition 870250088681, dated 09 / 30 / 2025,Page 73 / 90 6 / 11 in Seq ID No.: 42; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Seq ID No.: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Seq ID No.: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Seq ID No.: 23; and / or, said anti-TL1A antibody or antigen-binding fragment thereof comprises: < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in Seq ID No.: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Seq ID No.: 40; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3,as shown in No. ID SEQ: 42; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in No. ID SEQ: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in No. ID SEQ: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in No. ID SEQ: 23; and / or, said anti-TL1A antibody or antigen-binding fragment thereof comprises: Petition 870250088681, dated 09 / 30 / 2025, page 74 / 90 7 / 11 < 1> The variable region of the heavy chain comprises an amino acid sequence such as HCDR1, as shown in No. ID SEQ: 18; < 2> The variable region of the heavy chain comprises an amino acid sequence such as HCDR2, as shown in Sequence ID No.: 41; < 3> The variable region of the heavy chain comprises an amino acid sequence such as HCDR3,as shown in Sequence ID No.: 42; < 4> The variable region of the light chain comprises an amino acid sequence such as LCDR1, as shown in Sequence ID No.: 21; < 5> The variable region of the light chain comprises an amino acid sequence such as LCDR2, as shown in Sequence ID No.: 22; < 6> The variable region of the light chain comprises an amino acid sequence such as LCDR3, as shown in Seq ID No.

23.

4. Said anti-TL1A antibody or antigen-binding fragment thereof, according to claim 1, characterized in that the amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is as shown in Seq ID No. 3, Seq ID No. 16, Seq ID No. 7, Seq ID No. 24, Seq ID No. 26-31, and / or the amino acid sequence of the variable region of the light chain of the anti-TL1A antibody or antigen-binding fragment thereof is as shown in Seq ID No. 5, Seq ID No. 17, Seq ID No. 9,No. ID SEQ:

25.

5. The said anti-TL1A antibody or antigen-binding fragment thereof, according to claim 1, characterized in that it further comprises any of the following features: Petition 870250088681, dated 09 / 30 / 2025, page 75 / 90 8 / 11 1) The amino acid sequence of the variable region of the heavy chain of the said anti-TL1A antibody or antigen-binding fragment thereof is as shown in No. ID SEQ: 3, and the amino acid sequence of the variable region of the light chain is as shown in No. ID SEQ: 5; 2) The amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is shown in Sequence ID No. 16, and the amino acid sequence of the variable region of the light chain is shown in Sequence ID No. 17; 3) The amino acid sequence of the variable region of the heavy chain of the aforementioned anti-TL1A antibody or antigen-binding fragment thereof is shown in Sequence ID No. 7, and the amino acid sequence of the variable region of the light chain is shown in Sequence ID No. 9; 4) The amino acid sequence of the variable region of the heavy chain of the aforementioned anti-TL1A antibody or antigen-binding fragment thereof is shown in Sequence ID No. 24, and the amino acid sequence of the variable region of the light chain is shown in Sequence ID No. 25; 5) The amino acid sequence of the variable region of the heavy chain of the aforementioned anti-TL1A antibody or antigen-binding fragment thereof is shown in Sequence ID No. 26, and the amino acid sequence of the variable region of the light chain is shown in Sequence ID No. 25; 6) The amino acid sequence of the variable region of the heavy chain of the aforementioned anti-TL1A antibody or antigen-binding fragment thereof is shown in Sequence ID No. 27, and the amino acid sequence of the variable region of the light chain is shown in Sequence ID No. 25; 7) The amino acid sequence of the variable region of the heavy chain of the aforementioned anti-TL1A antibody or antigen-binding fragment of the same is shown in Sequence ID No. 28, and the amino acid sequence of the variable region of the light chain is shown in Sequence ID No. 25; 8) The amino acid sequence of the variable region of the heavy chain of the aforementioned anti-TL1A antibody or antigen-binding fragment thereof is shown in Sequence ID No. 29, and the amino acid sequence of the variable region of the light chain is shown in Sequence ID No. 25; 9) The amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is shown in Sequence ID No. 30, and the amino acid sequence of the variable region of the light chain is shown in Sequence ID No. 25; 10) The amino acid sequence of the variable region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is as shown in SEQ ID No. 31, and the amino acid sequence of the variable region of the light chain is as shown in SEQ ID No.

25.

6. Said anti-TL1A antibody or antigen-binding fragment thereof, according to claim 1, characterized in that said anti-TL1A antibody or antigen-binding fragment thereof is selected from a complete antibody, a monochain antibody or an antibody fragment; preferably, the constant region of the heavy chain of said complete antibody is an IgG1 constant region and / or said constant region of the light chain is a kappa chain constant region. 7.The aforementioned anti-TL1A antibody or antigen-binding fragment thereof, according to claim 1, characterized in that the amino acid sequence of the constant region of the heavy chain of said anti-TL1A antibody or antigen-binding fragment thereof is shown in SEQ ID No. 33; and / or the amino acid sequence of the constant region of the light chain of said anti-TL1A antibody or antigen-binding fragment thereof is shown in SEQ ID No.

34.

8. Isolated polynucleotide, characterized in that said polynucleotide encodes the variable region of the heavy chain and / or the variable region of the light chain or the complete amino acid sequence of the anti-TL1A antibody or antigen-binding fragment thereof, according to any of claims 1 to 7. 9.The aforementioned polynucleotide, according to claim 8, characterized in that the polynucleotide sequence encoding the variable region of the heavy chain of the anti-TL1A antibody or antigen-binding fragment thereof is as shown in Sequence ID No. 2, Sequence ID No. 6, Sequence ID No. 35, Sequence ID No. 37, Sequence ID No. 43-48; and / or a nucleotide sequence encoding the variable region of the anti-TL1A antibody light chain or antigen-binding fragment thereof, as shown in Sequence ID No. 4, Sequence ID No. 8, Sequence ID No. 36, Sequence ID No.

38.

10. Nucleic acid construct, characterized in that it contains said isolated polynucleotide in claim 8 or 9.

11. Cell, characterized in that it contains said construct in claim 10 or has said exogenous polynucleotide in claim 8 or 9 integrated into its genome. 12.The aforementioned method for preparing an anti-TL1A antibody or antigen-binding fragment thereof, according to any one of claims 1 to 7, characterized in that it comprises the following steps: cultivating the cells described in claim 11 under suitable conditions to express the anti-TL1A antibody or its antigen-binding fragment, thereby expressing said anti-TL1A antibody or antigen-binding fragment thereof. 13.Use of said anti-TL1A antibody or antigen-binding fragment thereof, according to any one of claims 1 to 7, characterized in that it is used in the preparation of a therapeutic drug for a disease or in the preparation of a diagnostic drug for a disease; preferably, said disease is selected from inflammatory bowel disease, gastrointestinal diseases associated with cystic fibrosis, colitis, irritable bowel syndrome, eosinophilic esophagitis, atopic dermatitis, eczema, scleroderma, arthritis or rheumatoid arthritis, alone or in combination.

14. Said use, according to claim 13, characterized in that the inflammatory bowel disease is Crohn's disease or ulcerative colitis.

15. Pharmaceutical composition, characterized in that the pharmaceutical composition comprises the anti-TL1A antibody or antigen-binding fragment thereof as per claims 1 to 7. Petition 870250088681, dated 09 / 30 / 2025, pp. 79 / 90.

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