Anti-sortilin antibodies and their methods of use

Description

FIELD

[0001] This present disclosure relates to anti-Sortilin antibodies, and therapeutic uses of such antibodies.BACKGROUND

[0002] Sortilin is a Type I transmembrane protein that acts both as a receptor of several ligands, and in the sorting of select cargo from the trans-Golgi network (TGN) to late endosomes and lysosomes for degradation. Sortilin harbors a large extracellular domain that is part of the VPS10 family, homologous to yeast VPS10P, and contains of a 1 0-blade beta-propeller structure and a cysteine-rich 10CC module (Nykjaer, A et al., (2012) Trends Neurosci 35: 261-270; and Zheng, Y et al., (2011) PLoS One 6: (21023). A small fraction of Sortilin may be shed by activity of ADAM10 or gamma-Secretase (<5%) (Nykjaer, A et al., (2012) Trends Neurosci 35: 261-270; and Willnow, TE et al., (2011) Curr Opin Lipidol 22: 79-85).

[0003] Sortilin binds the secreted protein Progranulin (PGRN) and targets it for lysosomal degradation, thus negatively regulating extracellular levels of PGRN (Hu, F et al. (2010) Neuron 68, 654-667. In line with this, deficiency of Sortilin significantly increases plasma PGRN levels both in mouse models in vivo and human cells in vitro (Carrasquillo, M.M et al., (2010) Am J Hum Genet 87, 890-897; Lee, W.C et al., (2014) Hum Mol Genet 23, 1467-1478). Moreover, a polymorphism in Sortilin was shown to be strongly assoiated with PGRN serum levels in humans (Carrasquillo MM e al., (2010), Am J Hum Genet. 10; 87(6):890-7).

[0004] Progranulin (PGRN) is a secreted, growth factor-like, trophic, and anti-inflammatory protein, which also plays a role as an adipokine involved in diet-induced obesity and insulin resistance (Nguyen DA et al., (2013). Trends in Endocrinology and Metabolism, 24, 597- 606). Progranulin deficiency accounts for roughly 25% of all heritable forms of frontotemporal dementia (FTD), an early-onset neurodegenerative disease. Patients with heterozygous loss-of-function mutations in PGRN have ~50% reduced extracellular levels of the protein and they will invariably develop FTD, making PGRN a causal gene for the disease (Baker, M et al., (2006) Nature 442, 916-919; Carecchio M et al., (2011) J Alzheimers Dis 27, 781-790; Cruts, M et al., (2008) Trends Genet 24, 186-194; Galimberti, D et al., (2010) J Alzheimers Dis 19, 171-177). In addition, PGRN mutant alleles have been identified in Alzheimer's disease patients (Seelaar, H et al., (2011). Journal of neurology, neurosurgery, and psychiatry 82, 476-486). Importantly, PGRN acts protectively in several disease models with increased PGRN levels, accelerating behavioral recovery from ischemia (Tao, J et al., (2012) Brain Res 1436, 130-136; Egashira, Y. et al., (2013). J Neuroinflammation 10, 105), suppressing locomotor deficits in a Parkinson's disease model (Van Kampen, J.M et al. (2014). PLoS One 9, e97032), attenuating pathology in a model of amyotriphic lateral sclerosis (Laird, A.S et al., (2010). PLoS One 5, ex13368.) and arthritis (Tang, W et al., (2011). Science 332, 478-484) and preventing memory deficits in an Alzheimer's disease model (Minami, S.S et al., (2014). Nat Med 20, 1157-1164).

[0005] Sortilin also binds directly to pro-neurotrophins, such as pro-nerve growth factor (pro-NGF), pro-BDNF, pro-neurotrophin-3, etc., which harbor a pro-domain and are typically pro-apoptotic. Such pro-neurotrophin precursors are released during stress, and Sortilin is involved in regulating their release as well as binding on the receiving cell and stimulation of apoptosis in conjunction with p75NTR (Willnow, TE et al., (2008) Nat Rev Neurosci 9: 899-909; Nykjaer, A et al., Trends Neurosci 35: 261-270; and Nykjaer, A et al., (2004) Nature 427: 843-848; Hiroko Yano et al., (2009) J Neurosci.; 29: 14790-14802.Teng U.K., et al., J. Neurosci. 25:5455-5463(2005)). Sortilin also binds to p75NTR directly (Skeldal S et al., (2012) J Biol Chem.; 287:43798). Sortilin also binds to neurotensin in a region that partially overlaps with Progranulin binding (Quistgaard, EM et al., (2009) Nat Struct Mol Biol 16: 96-98; and Zheng, Y et al., PLoS One 6: e21023). Sortilin also interacts with the Trk receptors NTRK1, NTRK2, and NTRK3; and can regulate their anterograde axonal transport and signaling (Vaegter, CB et al., (2011) Nat. Neurosci. 14:54-61). Sortilin also interacts with and regulates the processing and trafficking of amyloid precursor protein and the resulting production of pathological beta amyloid peptides (Gustafsen C et al., (2013). J Neurosci._2;33(1):64-71).

[0006] Sortilin has also been shown to bind to apolipoproteins and lipoprotein lipase; thus, deficiency leads to reduced VLDL release from liver and reduced cholesterol (Willnow, TE et al., (2011) Curr Opin Lipidol 22: 79-85; Kjolb), M et al., (2010) Cell Metab 12: 213-223; Nilsson, SK et al., (2007) Biochemistry 46: 3896-3904.; Nilsson, SK et al., (2008) J Biol Chem 283: 25920-25927; and Klinger, SC et al., (2011) J Cell Sci 124: 1095-1105). Recently, Sortilin has also been implicated in binding to APP directly (Gustafsen, C et al., (2013) J. Neurosc. 33:64-71) and also to the APP processing enzyme BACE1 (Gustafsen,C et al., (2013) J. Neurosc.33:64-71; and Finan, GM et al., J Biol Chem 286: 12602-12610). Sortilin also binds to apolipoprotein E (APOE), to the A beta peptide (Carlo, AS et al., (2013) J. Neurosc, 33: 358-370), and to PCSK9 (Gustafsen et al, (2014) Cell Metab, 19: 310-318). Sortilin has also been shown to bind to and regulate extracellular levels of PCSK9, which directs low-density lipoprotein receptor for degradation in lysosomes, resulting in increased levels of LDL cholesterol (Gustafsen C et al., (2014). Cell Metab. 2014 Feb 4;19(2):310-8).

[0007] When present at intracellular vesicles such as endosomes, the amino-terminal extracellular domain of Sortilin is directed towards the lumen, where cargo of the vesicle is present. The carboxy-terminal intracellular / cytoplasmic domain of Sortilin, however, binds to a series of adaptor proteins, which regulate its trafficking from the surface and within intracellular compartments. These include AP2 (a clathrin adaptor to modulate endocytosis from the cell surface), and the Retromer Complex / AP1, which modulate movement from early endosomes to Golgi for recycling; and interaction with GGA (Golgi-localizing, gamma-ear containing, ADP-ribosylation factor binding) family proteins for movement from Golgi directly to early endosomes, usually for subsequent degradation through lysosomes. Thus, Sortilin can bind to ligands at its luminal domain, while engaging the cytoplasmic adaptors that determine its destination to determine intracellular fates, such as degradation for Progranulin and other factors.

[0008] Through its various interactions with proteins, such as Progranulin, Sortilin and its multiple ligands have been shown to be involved in various diseases, disorders, and conditions, such as frontotemporal dementia, amyotrophic lateral sclerosis, amyotrophic lateral sclerosis-frontotemporal dementia phenotypes. Alzheimer's disease, Parkinson's disease, depression, neuropsyciatric disorders, vascular dementia, seizures, retinal dystrophy, age related macular degeneration, glaucoma, traumatic brain injury, aging, seizures, wound healing, stroke, arthritis, and atherosclerotic vascular diseases.

[0009] Accordingly, there is a need for therapeutic antibodies that specifically bind Sortilin proteins and block the binding of Sortilin to its ligands, such as Progranulin, or otherwise modulate the effective concentration of the ligands, in order to treat one or more diseases, disorders, and conditions associated with Sortilin activity.

[0010] WO2016164637, WO2017009327 and WO2016164608 disclose anti-sortilin antibodies.SUMMARY

[0011] The present disclosure is generally directed to compositions that include antibodies, e.g., monoclonal, chimeric, humanized antibodies, antibody fragments, etc., that specifically bind human Sortilin, and to methods of using such compositions.

[0012] Any mentions in the description to methods of treatment refer to the compounds, pharmaceutical compositions and medicaments of the present invention for use in a method of treatment of the human (or animal) body by therapy.

[0013] The invention is defined by the appended claims. Any aspects, embodiments and examples of the present disclosure which do not fall under the scope of the appended claims do not form part of the invention and are merely provided for illustrative purposes.

[0014] In a first aspect, the present invention provides an antibody that binds to a human Sortilin protein, wherein the antibody comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 56 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 57.

[0015] In a second aspect, the present invention provides an antibody that binds to a human Sortilin protein, wherein the antibody comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 56 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 60.

[0016] In some embodiments that may be combined with any of the previous aspects, an anti-Sortilin antibody of the present invention is of the IgG class, the IgM class, or the IgA class. In certain specific embodiments, the anti-Sortilin antibody is of the IgG class and has an IgG1, IgG2, IgG3, or IgG4 isotype. In some embodiments of the present invention, provided is an anti-Sortilin antibody of the IgG1, IgG2, IgG3, or IgG4 isotype, wherein (a) the antibody is an IgG1 or IgG2 isotype and the Fc region comprises an amino acid substitution at position P331S, wherein the numbering of the residue position is according to EU numbering; (b) the antibody is an IgG1 isotype and the Fc region comprises amino acid substitutions at positions L234A, L235A, and P33 IS, wherein the numbering of the residue position is according to EU numbering; (c) the antibody is an IgG1, IgG2, or IgG4 isotype and the Fc region comprises an amino acid substitution at position N297A, wherein the numbering of the residue position is according to EU numbering; or (d) the Fc region comprises an amino acid substitution at positions S267E and L328F, wherein the numbering of the residue position is according to EU numbering. In some embodiments, the antibody is an IgG1 isotype and the Fc region comprises amino acid substitutions at positions L234A, L235A, and P33 IS, wherein the numbering of the residue position is according to EU numbering.

[0017] In some aspects, the present invention provides an antibody that binds to a human Sortilin protein, wherein the antibody comprises a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 and a light chain comprising the amino acid sequence of SEQ ID NO: 142.

[0018] In some aspects, the present invention provides an antibody that binds to a human Sortilin protein, wherein the antibody comprises a heavy chain comprising the amino acid sequence of SEQ ID NO: 138 and a light chain comprising the amino acid sequence of SEQ ID NO: 142.

[0019] In the present invention the human Sortilin protein may comprise the amino acid sequence of SEQ ID NO: 81.

[0020] In some embodiments that may be combined with any of the previous embodiments, the antibody is a human antibody, a bispecific antibody, a monoclonal antibody, a multivalent antibody, a conjugated antibody, or a chimeric antibody. In certain embodiments, an anti-Sortilin antibody of the present invention is a monoclonal antibody.

[0021] In some embodiments, an anti-Sortilin antibody of the present invention is a bispecific antibody reconizing a Sortilin protein and a second antigen. In certain embodiments, bispecific antibodies of the present invention recognize both Sortilin and an antigen facilitating transport across the blood-brain-barrier. In some specific embodiments, the first antigen is Sortilin and the second antigen is Sortilin, transferrin receptor (TR), insulin receptor (HIR), insulin-like growth factor receptor (IGFR), low-density lipoprotein receptor related proteins 1 and 2 (LPR-1 and 2), diphtheria toxin receptor, CRM197, a Ilama single domain antibody, TMEM 30(A), a protein transduction domain, TAT, Syn-B, penetratin, a poly-arginine peptide, an angiopep peptide, basigin, Glut!, CD98hc, or ANG1005.

[0022] In certain embodiments of the present invention, the anti-Sortilin antibody is an antibody fragment that binds to a human Sortilin protein, In certain embodiments that may be combined with any of the preceding embodiments, the anti-Sortilin antibody fragment is an Fab, Fab', Fab'-SH. F(ab')2, Fv, or scFv fragment. In some aspects, the present invention provides an isolated nucleic acid comprising a nucleic acid sequence encoding an anti-Sortilin antibody according to the claims. Accordingly, some aspects provide a vector containing a nucleic acid encoding the anti-Sortilin antibody, and some aspects provide an isolated host cell containing such a vector. In certain aspects, the present invention provides a method of producing an anti-Sortilin antibody that binds to Sortilin, comprising culturing such an isolated host cell so that the anti-Sortilin antibody is produced. In certain embodiments, the method further comprises recovering the antibody produced by the cell.

[0023] In another aspect, the present invention relates to a pharmaceutical composition comprising any of the anti-Sortilin antibodies according to the claims and a pharmaceutically acceptable carrier. In some embodiments, the present invention relates to an antibody according to the claims for use as a medicamant. In some embodiments, the antibody is for use in a method of preventing, reducing risk for or treating a disease, disorder or injury selected from frontotemporal dementia, Alzheimer's disease, vascular dementia, seizures, retinal dystrophy, amyotrophic lateral sclerosis, traumatic brain injury, a spinal cord injury, neuropathic pain, dementia, stroke, Parkinson's disease, retinal degeneration, multiple sclerosis, septic shock, arthritis, or osteoarthritis.

[0024] In certain aspects, provided herein is an antibody according to the claims for use in a method of inhibiting neuroinflammation, or axonopathy characterized by short axonal outgrowth and aberrant branching.

[0025] In certain aspects, provided herein is an antibody according to the claims for use in a method of promoting wound healing.

[0026] In certain aspects, provided herein is an antibody according to the claims for use in a method at preventing, reducing risk, or treating arthritis, or an inflammatory disorder.

[0027] In some aspects, provided herein is an in vitro method of inhibiting the interaction between Sortilin and Progranulin, the method comprising exposing a cell expressing Sortilin to an anti-Sortilin antibody or a pharmaceutical composition of the present claims. In some embodiments, the method further comprises decreasing the level of Sortilin expressed on the cell surface. In some embodiments, extracellular levels of Progranulin are increased. In some embodiments, the individual has one or more mutations in the gene encoding Progranulin. In some the individual is heterozygous for one or more loss-of-function mutations in the gene encoding Progranulin. The individual has a c9orf72 hexanucleotide repeat expansion. The individual has or is at risk for frontotemporal dementia, Alzheimer's disease, or amyotrophic lateral sclerosis.

[0028] In some embodiments that may be combined with any of the previous aspects or embodiments, the anti-Sortilin antibody comprises two or more anti-Sortilin antibodies.BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIGS. 1A-1C provide pharmacokinetic and pharmacodynamic studies of non-human primates administered single doses of anti-Sortilin antibody S-60-15.1 [N33T] LALAPS (S-60-15.1 [N33T] with huIgG1 with L234A / L235A / P331S mutations). FIG. 1A provides the level of SORT1 in peripheral white blood cells as a percentage from baseline at the indicated times after treatment (hours) with the specified anti-Sortilin antibody doses. SORT1 expression decreased with all of the anti-Sortilin antibody doses tested. Higher antibody doses (60 mg / kg, 200 mg / kg) resulted in both an earlier and more prolonged decrease of SORT1 levels compared to lower anti-Sortilin antibody doses (5mg / kg, 20 mg / kg). FIG. 1B provides the levels of PGRN in the plasma as a percentage from baseline at the indicated times after treatment (hours) with the specified anti-Sortilin antibody doses. The levels of PGRN increased in a time- and dose-dependent manner. In particular, plasma PGRN levels increased 3- to 4-fold at C max , compared to baseline levels, for all anti-Sortilin antibody doses tested and remained elevated for longer periods of time at the higher antibody doses. FIG. 1C provides the levels of PGRN in CSF as a percentage from baseline at the indicated times after treatment (hours) with the specified anti-Sortilin antibody doses. CSF PGRN levels increased 2- to 3-fold above baseline in animals administered either 20 mg / kg, 60 mg / kg, or 200 mg / kg. As observed with plasma PGRN levels ( FIG. 1B), CSF PGRN levels remained elevated over time in the higher antibody dose groups. For FIGS. 1A-1C, n = 3 animals per dose. FIGS. 2A-2C provide pharmacokinetic and pharmacodynamic studies of non-human primates administered repeat doses of anti-Sortilin antibody S-60-15.1 [N33T] LALAPS. Animals (2 males and 2 females) were administered anti-Sortilin antibody S-60-15.1 [N33T] LALAPS at a dose of 60mg / kg once per week for four weeks. The days on which dosing occurred are represented by the vertical dashed lines. FIG. 2A provides the mean (+ / - standard deviation) of the concentration of SORT1 in peripheral white blood cells (WBCs) as a percentage of baseline at the indicated times (days). SORT1 levels in peripheral white blood cells remained decreased throughout the duration of the study. FIG. 2B provides the mean (+ / - standard deviation) of the concentration of PGRN in plasma as a percentage of baseline (normalized) at the indicated times (days). Plasma PGRN levels increased to 5- to 6-fold above baseline at peak levels. A decrease in plasma PGRN was observed following the fourth and final administration of anti-Sortilin antibody; however, the plasma PGRN levels remained elevated by 2-fold above baseline. FIG. 2C provides the mean (+ / - standard deviation) of the concentration of PGRN in CSF as a percentage of baseline (normalized) at the indicated times (days). CSF PGRN levels were increased 3- to 4-fold above baseline ( FIG. 2C). DETAILED DESCRIPTIONDefinitions

[0030] As used herein, the term "preventing" includes providing prophylaxis with respect to occurrence or recurrence of a particular disease, disorder, or condition in an individual. An individual may be predisposed to, susceptible to a particular disease, disorder, or condition, or at risk of developing such a disease, disorder, or condition, but has not yet been diagnosed with the disease, disorder, or condition.

[0031] As used herein, an individual "at risk" of developing a particular disease, disorder, or condition may or may not have detectable disease or symptoms of disease, and may or may not have displayed detectable disease or symptoms of disease prior to the treatment methods described herein. "At risk" denotes that an individual has one or more risk factors, which are measurable parameters that correlate with development of a particular disease, disorder, or condition, as known in the art. An individual having one or more of these risk factors has a higher probability of developing a particular disease, disorder, or condition than an individual without one or more of these risk factors.

[0032] As used herein, the term "treatment" refers to clinical intervention designed to alter the natural course of the individual being treated during the course of clinical pathology. Desirable effects of treatment include decreasing the rate of progression, ameliorating or palliating the pathological state, and remission or improved prognosis of a particular disease, disorder, or condition. An individual is successfully "treated", for example, if one or more symptoms associated with a particular disease, disorder, or condition are mitigated or eliminated.

[0033] An "effective amount" refers to at least an amount effective, at dosages and for periods of time necessary, to achieve the desired therapeutic or prophylactic result. An effective amount can be provided in one or more administrations. An effective amount herein may vary according to factors such as the disease state, age, sex, and weight of the individual, and the ability of the treatment to elicit a desired response in the individual. An effective amount is also one in which any toxic or detrimental effects of the treatment are outweighed by the therapeutically beneficial effects. For prophylactic use, beneficial or desired results include results such as eliminating or reducing the risk, lessening the severity, or delaying the onset of the disease, including biochemical, histological and / or behavioral symptoms of the disease, its complications and intermediate pathological phenotypes presenting during development of the disease. For therapeutic use, beneficial or desired results include clinical results such as decreasing one or more symptoms resulting from the disease, increasing the quality of life of those suffering from the disease, decreasing the dose of other medications required to treat the disease, enhancing effect of another medication such as via targeting, delaying the progression of the disease, and / or prolonging survival. An effective amount of drug, compound, or pharmaceutical composition is an amount sufficient to accomplish prophylactic or therapeutic treatment either directly or indirectly. As is understood in the clinical context, an effective amount of a drug, compound, or pharmaceutical composition may or may not be achieved in conjunction with another drug, compound, or pharmaceutical composition. Thus, an "effective amount" may be considered in the context of administering one or more therapeutic agents, and a single agent may be considered to be given in an effective amount if, in conjunction with one or more other agents, a desirable result may be or is achieved

[0034] As used herein, administration "in conjunction" with another compound or composition includes simultaneous administration and / or administration at different times. Administration in conjunction also encompasses administration as a co-formulation or administration as separate compositions, including at different dosing frequencies or intervals, and using the same route of administration or different routes of administration.

[0035] An "individual" for purposes of treatment, prevention, or reduction of risk refers to any animal classified as a mammal, including humans, domestic and farm animals, and zoo, sport, or pet animals, such as dogs, horses, rabbits, cattle, pigs, hamsters, gerbils, mice, ferrets, rats, cats, and the like. Preferably, the individual is human.

[0036] The terms "Sortilin" or "Sortilin polypeptide" are used interchangeably herein refer herein to any native Sortilin from any mammalian source, including primates (e.g., humans and cynos) and rodents (e.g., mice and rats), unless otherwise indicated. In some embodiments, the term encompasses both wild-type sequences and naturally occurring variant sequences, e.g., splice variants or allelic variants. In some embodiments, the term encompasses "full-length," unprocessed Sortilin as well as any form of Sortilin that results from processing in the cell. In some embodiments, the Sortilin is human Sortilin. In some embodiments, the amino acid sequence of an exemplary human Sortilin is SEQ ID NO: 81.

[0037] The terms "anti- Sortilin antibody," an "antibody that binds to Sortilin," and "antibody that specifically binds Sortilin" refer to an antibody that is capable of binding Sortilin with sufficient affinity such that the antibody is useful as a diagnostic and / or therapeutic agent in targeting Sortilin. In one embodiment, the extent of binding of an anti- Sortilin antibody to an unrelated, non- Sortilin polypeptide is less than about 10% of the binding of the antibody to Sortilin as measured, e.g., by a radioimmunoassay (RIA). In certain embodiments, an antibody that binds to Sortilin has a dissociation constant (KD) of < 1µM, < 100 nM, < 10 nM, < 1 nM, < 0.1 nM, < 0.01 nM, or < 0.001 nM (e.g., 10-8 M or less, e.g. from 10-8 M to 10-13 M, e.g., from 10-9 M to 10-13 M). In certain embodiments, an anti-Sortilin antibody binds to an epitope of Sortilin that is conserved among Sortilin from different species.

[0038] The term "immunoglobulin" (Ig) is used interchangeably with "antibody" herein. The term "antibody" herein is used in the broadest sense and specially covers monoclonal antibodies, polyclonal antibodies, multispecific antibodies (e.g., bispecific antibodies) including those formed from at least two intact antibodies, and antibody fragments so long as they exhibit the desired biological activity.

[0039] "Native antibodies" are usually heterotetrameric glycoproteins of about 150,000 Daltons, composed of two identical Light ("L") chains and two identical heavy ("H") chains. Each light chain is linked to a heavy chain by one covalent disulfide bond, while the number of disulfide linkages varies among the heavy chains of different immunoglobulin isotypes. Each heavy and light chain also has regularly spaced intra-chain disulfide bridges. Each heavy chain has at one end a variable domain (V H ) followed by a number of constant domains. Each light chain has a variable domain at one end (V L ) and a constant domain at its other end; the constant domain of the light chain is aligned with the first constant domain of the heavy chain, and the light chain variable domain is aligned with the variable domain of the heavy chain. Particular amino acid residues are believed to form an interface between the light chain and heavy chain variable domains.

[0040] For the structure and properties of the different classes of antibodies, see, e.g., Basic and Clinical Immunology, 8th Ed., Daniel P. Stites, Abba I. Terr and Tristram G. Parslow (eds.), Appleton & Lange, Norwalk, CT, 1994, page 71 and Chapter 6.

[0041] The light chain from any vertebrate species can be assigned to one of two clearly distinct types, called kappa ("κ") and lambda ("λ"), based on the amino acid sequences of their constant domains. Depending on the amino acid sequence of the constant domain of their heavy chains (CH), immunoglobulins can be assigned to different classes or isotypes. There are five classes of immunoglobulins: IgA, IgD, IgE, IgG, and IgM, having heavy chains designated alpha ("α"), delta ("δ"), epsilon ("ε"), gamma ("γ"), and mu ("µ"), respectively. The γ and α classes are further divided into subclasses (isotypes) on the basis of relatively minor differences in the CH sequence and function, e.g., humans express the following subclasses: IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2. The subunit structures and three-dimensional configurations of different classes of immunoglobulins are well known and described generally in, for example, Abbas et al., Cellular and Molecular Immunology, 4th ed. (W.B. Saunders Co., 2000).

[0042] The "variable region" or "variable domain" of an antibody, such as an anti-Sortilin antibody of the present disclosure, refers to the amino-terminal domains of the heavy or light chain of the antibody. The variable domains of the heavy chain and light chain may be referred to as "V H " and "V L ", respectively. These domains are generally the most variable parts of the antibody (relative to other antibodies of the same class) and contain the antigen binding sites.

[0043] The term "variable" refers to the fact that certain segments of the variable domains differ extensively in sequence among antibodies, such as anti-Sortilin antibodies of the present disclosure. The variable domain mediates antigen binding and defines the specificity of a particular antibody for its particular antigen. However, the variability is not evenly distributed across the entire span of the variable domains. Instead, it is concentrated in three segments called hypervariable regions (HVRs) both in the light-chain and the heavy chain variable domains. The more highly conserved portions of variable domains are called the framework regions (FR). The variable domains of native heavy and light chains each comprise four FR regions, largely adopting a beta-sheet configuration, connected by three HVRs, which form loops connecting, and in some cases forming part of, the beta-sheet structure. The HVRs in each chain are held together in close proximity by the FR regions and, with the HVRs from the other chain, contribute to the formation of the antigen-binding site of antibodies (see Kabat et al., Sequences of Immunological Interest, Fifth Edition, National Institute of Health, Bethesda, MD (1991)). The constant domains are not involved directly in the binding of antibody to an antigen, but exhibit various effector functions, such as participation of the antibody in antibody-dependent-cellular toxicity.

[0044] An "isolated" antibody, such as an anti-Sortilin antibody of the present disclosure, is one that has been identified, separated and / or recovered from a component of its production environment (e.g., naturally or recombinantly). Preferably, the isolated polypeptide is free of association with all other contaminant components from its production environment. Contaminant components from its production environment, such as those resulting from recombinant transfected cells, are materials that would typically interfere with research, diagnostic or therapeutic uses for the antibody, and may include enzymes, hormones, and other proteinaceous or non-proteinaceous solutes. In preferred embodiments, the polypeptide will be purified: (1) to greater than 95% by weight of antibody as determined by, for example, the Lowry method, and in some embodiments, to greater than 99% by weight; (2) to a degree sufficient to obtain at least 15 residues of N-terminal or internal amino acid sequence by use of a spinning cup sequenator, or (3) to homogeneity by SDS-PAGE under non-reducing or reducing conditions using Coomassie blue or, preferably, silver stain. Isolated antibody includes the antibody in situ within recombinant T cells since at least one component of the antibody's natural environment will not be present. Ordinarily, however, an isolated polypeptide or antibody will be prepared by at least one purification step.

[0045] The term "monoclonal antibody" as used herein refers to an antibody, such as a monoclonal anti-Sortilin antibody of the present disclosure, obtained from a population of substantially homogeneous antibodies, i.e., the individual antibodies comprising the population are identical except for possible naturally occurring mutations and / or post-translation modifications (e.g., isomerizations, amidations, etc.) that may be present in minor amounts. Monoclonal antibodies are highly specific, being directed against a single antigenic site. In contrast to polyclonal antibody preparations which typically include different antibodies directed against different determinants (epitopes), each monoclonal antibody is directed against a single determinant on the antigen. In addition to their specificity, the monoclonal antibodies are advantageous in that they are synthesized by the hybridoma culture, uncontaminated by other immunoglobulins. The modifier "monoclonal" indicates the character of the antibody as being obtained from a substantially homogeneous population of antibodies, and is not to be construed as requiring production of the antibody by any particular method. For example, the monoclonal antibodies to be used in accordance with the present invention may be made by a variety of techniques, including, but not limited to one or more of the following methods, immunization methods of animals including, but not limited to rats, mice, rabbits, guinea pigs, hamsters and / or chickens with one or more of DNA(s), virus-like particles, polypetide(s), and / or cell(s), the hybridoma methods, B-cell cloning methods, recombinant DNA methods, and technologies for producing human or human-like antibodies in animals that have parts or all of the human immunoglobulin loci or genes encoding human immunoglobulin sequences.

[0046] The terms "full-length antibody," "intact antibody" or "whole antibody" are used interchangeably to refer to an antibody, such as an anti-Sortilin antibody of the present disclosure, in its substantially intact form, as opposed to an antibody fragment. Specifically, whole antibodies include those with heavy and light chains including an Fc region. The constant domains may be native sequence constant domains (e.g., human native sequence constant domains) or amino acid sequence variants thereof. In some cases, the intact antibody may have one or more effector functions.

[0047] An "antibody fragment" comprises a portion of an intact antibody, preferably the antigen binding and / or the variable region of the intact antibody. Examples of antibody fragments include Fab, Fab', F(ab') 2 and Fv fragments; diabodies; linear antibodies (see U.S. Patent 5,641,870, Example 2; Zapata et al., Protein Eng. 8(10): 1057-1062 (1995)); single-chain antibody molecules and multispecific antibodies formed from antibody fragments.

[0048] Papain digestion of antibodies, such as anti-Sortilin antibodies of the present disclosure, produces two identical antigen-binding fragments, called "Fab" fragments, and a residual "Fc" fragment, a designation reflecting the ability to crystallize readily. The Fab fragment consists of an entire L chain along with the variable region domain of the H chain (V H ), and the first constant domain of one heavy chain (C H 1). Each Fab fragment is monovalent with respect to antigen binding, i.e., it has a single antigen-binding site. Pepsin treatment of an antibody yields a single large F(ab') 2 fragment which roughly corresponds to two disulfide linked Fab fragments having different antigen-binding activity and is still capable of cross-linking antigen. Fab' fragments differ from Fab fragments by having a few additional residues at the carboxy terminus of the C H 1 domain including one or more cysteines from the antibody hinge region. Fab'-SH is the designation herein for Fab' in which the cysteine residue(s) of the constant domains bear a free thiol group. F(ab') 2 antibody fragments originally were produced as pairs of Fab' fragments which have hinge cysteines between them. Other chemical couplings of antibody fragments are also known.

[0049] The Fc fragment comprises the carboxy-terminal portions of both H chains held together by disulfides. The effector functions of antibodies are determined by sequences in the Fc region, the region which is also recognized by Fc receptors (FcR) found on certain types of cells.

[0050] "Fv" is the minimum antibody fragment which contains a complete antigen-recognition and - binding site. This fragment consists of a dimer of one heavy- and one light-chain variable region domain in tight, non-covalent association. From the folding of these two domains emanate six hypervariable loops (3 loops each from the H and L chain) that contribute the amino acid residues for antigen binding and confer antigen binding specificity to the antibody. However, even a single variable domain (or half of an Fv comprising only three HVRs specific for an antigen) has the ability to recognize and bind antigen, although at a lower affinity than the entire binding site.

[0051] "Single-chain Fv" also abbreviated as "sFv" or "scFv" are antibody fragments that comprise the VH and VL antibody domains connected into a single polypeptide chain. Preferably, the sFv polypeptide further comprises a polypeptide linker between the V H and V L domains which enables the sFv to form the desired structure for antigen binding. For a review of the sFv, see Pluckthun in The Pharmacology of Monoclonal Antibodies, vol. 113, Rosenburg and Moore eds., Springer-Verlag, New York, pp. 269-315 (1994).

[0052] "Functional fragments" of antibodies, such as anti-Sortilin antibodies of the present disclosure, comprise a portion of an intact antibody, generally including the antigen binding or variable region of the intact antibody or the F region of an antibody which retains or has modified FcR binding capability. Examples of antibody fragments include linear antibody, single-chain antibody molecules and multispecific antibodies formed from antibody fragments.

[0053] The term "diabodies" refers to small antibody fragments prepared by constructing sFv fragments (see preceding paragraph) with short linkers (about 5-10) residues) between the V H and V L domains such that inter-chain but not intra-chain pairing of the variable domains is achieved, thereby resulting in a bivalent fragment, i.e., a fragment having two antigen-binding sites. Bispecific diabodies are heterodimers of two "crossover" sFv fragments in which the V H and V L domains of the two antibodies are present on different polypeptide chains.

[0054] As used herein, a "chimeric antibody" refers to an antibody (immunoglobulin), such as a chimeric anti-Sortilin antibody of the present disclosure, in which a portion of the heavy and / or light chain is identical with or homologous to corresponding sequences in antibodies derived from a particular species or belonging to a particular antibody class or subclass, while the remainder of the chain(s) is(are) identical with or homologous to corresponding sequences in antibodies derived from another species or belonging to another antibody class or subclass, as well as fragments of such antibodies, so long as they exhibit the desired biological activity. Chimeric antibodies of interest herein include PRIMATIZED ®< antibodies wherein the antigen-binding region of the antibody is derived from an antibody produced by, e.g., immunizing macaque monkeys with an antigen of interest. As used herein, "humanized antibody" is used a subset of "chimeric antibodies."

[0055] "Humanized" forms of non-human (e.g., murine) antibodies, such as humanized forms of anti-Sortilin antibodies of the present disclosure, are chimeric antibodies comprising amino acid residues from non-human HVRs and amino acid residues from human FRs. In certain embodiments, a humanized antibody will comprise substantially all of at least one, and typically two, variable domains, in which all or substantially all of the HVRs (e.g., CDRs) correspond to those of a non-human antibody, and all or substantially all of the FRs correspond to those of a human antibody. A humanized antibody optionally may comprise at least a portion of an antibody constant region derived from a human antibody. A "humanized form" of an antibody, e.g., a non-human antibody, refers to an antibody that has undergone humanization.

[0056] A "human antibody" is one that possesses an amino-acid sequence corresponding to that of an antibody, such as an anti-Sortilin antibody of the present disclosure, produced by a human and / or has been made using any of the techniques for making human antibodies as disclosed herein. This definition of a human antibody specifically excludes a humanized antibody comprising non-human antigen-binding residues. Human antibodies can be produced using various techniques known in the art, including phage-display libraries and yeast-based platform technologies. Human antibodies can be prepared by administering the antigen to a transgenic animal that has been modified to produce such antibodies in response to antigenic challenge, but whose endogenous loci have been disabled, e.g., immunized xenomice as well as generated via a human B-cell hybridoma technology.

[0057] The term "hypervariable region," "HVR," or "HV," when used herein refers to the regions of an antibody-variable domain, such as that of an anti-Sortilin antibody of the present disclosure, that are hypervariable in sequence and / or form structurally defined loops. Generally, antibodies comprise six HVRs; three in the V H (H1, H2, H3), and three in the V L (L1, L2, L3). In native antibodies, H3 and L3 display the most diversity of the six HVRs, and H3 in particular is believed to play a unique role in conferring fine specificity to antibodies. Naturally occurring camelid antibodies consisting of a heavy chain only are functional and stable in the absence of light chain.

[0058] A number of HVR delineations are in use and are encompassed herein. In some embodiments, the HVRs may be Kabat complementarity-determining regions (CDRs) based on sequence variability and are the most commonly used (Kabat et al., supra). In some embodiments, the HVRs may be Chothia CDRs. Chothia refers instead to the location of the structural loops (Chothia and Lesk J. Mol. Biol. 196:901-917 (1987)). In some embodiments, the HVRs may be AbM HVRs. The AbM HVRs represent a compromise between the Kabat CDRs and Chothia structural loops, and are used by Oxford Molecular's AbM antibody-modeling software. In some embodiments, the HVRs may be "contact" HVRs. The "contact" HVRs are based on an analysis of the available complex crystal structures. The residues from each of these HVRs are noted below.

[0059] HVRs may comprise "extended HVRs" as follows: 24-36 or 24-34 (L1), 46-56 or 50-56 (L2), and 89-97 or 89-96 (L3) in the VL, and 26-35 (H1), 50-65 or 49-65 (a preferred embodiment) (H2), and 93-102, 94-102, or 95-102 (H3) in the VH. The variable-domain residues are numbered according to Kabat et al., supra, for each of these extended-HVR definitions.

[0060] "Framework" or "FR" residues are those variable-domain residues other than the HVR residues as herein defined.

[0061] An "acceptor human framework" as used herein is a framework comprising the amino acid sequence of a V L or V H framework derived from a human immunoglobulin framework or a human consensus framework. An acceptor human framework "derived from" a human immunoglobulin framework or a human consensus framework may comprise the same amino acid sequence thereof, or it may comprise pre-existing amino acid sequence changes. In some embodiments, the number of pre-existing amino acid changes are 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, 5 or less, 4 or less, 3 or less, or 2 or less. Where pre-existing amino acid changes are present in a VH, preferable those changes occur at only three, two, or one of positions 71H, 73H and 78H; for instance, the amino acid residues at those positions may by 71A, 73T and / or 78A. In one embodiment, the VL acceptor human framework is identical in sequence to the V L human immunoglobulin framework sequence or human consensus framework sequence.

[0062] A "human consensus framework" is a framework that represents the most commonly occurring amino acid residues in a selection of human immunoglobulin V L or V H framework sequences. Generally, the selection of human immunoglobulin V L or V H sequences is from a subgroup of variable domain sequences. Generally, the subgroup of sequences is a subgroup as in Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, MD (1991). Examples include for the V L , the subgroup may be subgroup kappa I, kappa II, kappa III or kappa IV as in Kabat et al., supra. Additionally, for the V H , the subgroup may be subgroup I, subgroup II, or subgroup III as in Kabat et al., supra.

[0063] An "amino-acid modification" at a specified position, e.g., of an anti-Sortilin antibody of the present disclosure, refers to the substitution or deletion of the specified residue, or the insertion of at least one amino acid residue adjacent the specified residue. Insertion "adjacent" to a specified residue means insertion within one to two residues thereof. The insertion may be N-terminal or C-terminal to the specified residue. The preferred amino acid modification herein is a substitution.

[0064] An "affinity-matured" antibody, such as an anti-Sortilin antibody of the present disclosure, is one with one or more alterations in one or more HVRs thereof that result in an improvement in the affinity of the antibody for antigen, compared to a parent antibody that does not possess those alteration(s). In one embodiment, an affinity-matured antibody has nanomolar or even picomolar affinities for the target antigen. Affinity-matured antibodies are produced by procedures known in the art. For example, Marks et al., Bio / Technology 10:779-783 (1992) describes affinity maturation by VH- and VL-domain shuffling. Random mutagenesis of HVR and / or framework residues is described by, for example: Barbas et al. Proc Nat. Acad. Sci. USA 91:3809-3813 (1994); Schier et al. Gene 169:147-155 (1995); Yelton et al. J. Immunol. 155:1994-2004 (1995); Jackson et al., J. Immunol. 154(7):3310-9 (1995); and Hawkins et al, J. Mol. Biol. 226:889-896 (1992).

[0065] As use herein, the term "specifically recognizes" or "specifically binds" refers to measurable and reproducible interactions such as attraction or binding between a target and an antibody, such as an anti-Sortilin antibody of the present disclosure, that is determinative of the presence of the target in the presence of a heterogeneous population of molecules including biological molecules. For example, an antibody, such as an anti-Sortilin antibody of the present disclosure, that specifically or preferentially binds to a target or an epitope is an antibody that binds this target or epitope with greater affinity, avidity, more readily, and / or with greater duration than it binds to other targets or other epitopes of the target. It is also understood by reading this definition that, for example, an antibody (or a moiety) that specifically or preferentially binds to a first target may or may not specifically or preferentially bind to a second target. As such, "specific binding" or "preferential binding" does not necessarily require (although it can include) exclusive binding. An antibody that specifically binds to a target may have an association constant of at least about 10 3< M -1< or 10 4< M -1< , sometimes about 10 5< M -1< or 10 6< M -1< , in other instances about 10 6< M -1< or 10 7< M -1< , about 10 8< M -1< to 10 9< M -1< , or about 10 10< M -1< to 10 11< M -1< or higher. A variety of immunoassay formats can be used to select antibodies specifically immunoreactive with a particular protein. For example, solid-phase ELISA immunoassays are routinely used to select monoclonal antibodies specifically immunoreactive with a protein. See, e.g., Harlow and Lane (1988) Antibodies, A Laboratory Manual, Cold Spring Harbor Publications, New York, for a description of immunoassay formats and conditions that can be used to determine specific immunoreactivity.

[0066] As used herein, an "interaction" between a Sortilin protein and a second protein encompasses, without limitation, protein-protein interaction, a physical interaction, a chemical interaction, binding, covalent binding, and ionic binding. As used herein, an antibody "inhibits interaction" between two proteins when the antibody disrupts, reduces, or completely eliminates an interaction between the two proteins. An antibody of the present disclosure, or fragment thereof, "inhibits interaction" between two proteins when the antibody or fragment thereof binds to one of the two proteins.

[0067] An "agonist" antibody or an "activating" antibody is an antibody, such as an agonist anti-Sortilin antibody of the present disclosure, that induces (e.g., increases) one or more activities or functions of the antigen after the antibody binds the antigen.

[0068] A "blocking" antibody, an "antagonist" antibody, or an "inhibitory" antibody is an antibody, such as an anti-Sortilin antibody of the present disclosure, that inhibits or reduces (e.g., decreases) antigen binding to one or more ligand after the antibody binds the antigen, and / or that inhibits or reduces (e.g., decreases) one or more activities or functions of the antigen after the antibody binds the antigen. In some embodiments, blocking antibodies, antagonist antibodies, or inhibitory antibodies substantially or completely inhibit antigen binding to one or more ligand and / or one or more activities or functions of the antigen.

[0069] Antibody "effector functions" refer to those biological activities attributable to the Fc region (a native sequence Fc region or amino acid sequence variant Fc region) of an antibody, and vary with the antibody isotype.

[0070] The term "Fc region" herein is used to define a C-terminal region of an immunoglobulin heavy chain, including native-sequence Fc regions and variant Fc regions. Although the boundaries of the Fc region of an immunoglobulin heavy chain might vary, the human IgG heavy-chain Fc region is usually defined to stretch from an amino acid residue at position Cys226, or from Pro230, to the carboxyl-terminus thereof. The C-terminal lysine (residue 447 according to the EU numbering system) of the Fc region may be removed, for example, during production or purification of the antibody, or by recombinantly engineering the nucleic acid encoding a heavy chain of the antibody. Accordingly, a composition of intact antibodies may comprise antibody populations with all K447 residues removed, antibody populations with no K447 residues removed, and antibody populations having a mixture of antibodies with and without the K447 residue. Suitable native-sequence Fc regions for use in the antibodies of the present disclosure include human IgG1, IgG2, IgG3 and IgG4.

[0071] A "native sequence Fc region" comprises an amino acid sequence identical to the amino acid sequence of an Fc region found in nature. Native sequence human Fc regions include a native sequence human IgG1 Fc region (non-A and A allotypes); native sequence human IgG2 Fc region; native sequence human IgG3 Fc region; and native sequence human IgG4 Fc region as well as naturally occurring variants thereof.

[0072] A "variant Fc region" comprises an amino acid sequence which differs from that of a native sequence Fc region by virtue of at least one amino acid modification, preferably one or more amino acid substitution(s). Preferably, the variant Fc region has at least one amino acid substitution compared to a native sequence Fc region or to the Fc region of a parent polypeptide, e.g. from about one to about ten amino acid substitutions, and preferably from about one to about five amino acid substitutions in a native sequence Fc region or in the Fc region of the parent polypeptide. The variant Fc region herein will preferably possess at least about 80% homology with a native sequence Fc region and / or with an Fc region of a parent polypeptide, and most preferably at least about 90% homology therewith, more preferably at least about 95% homology therewith.

[0073] "Fc receptor" or "FcR" describes a receptor that binds to the Fc region of an antibody. The preferred FcR is a native sequence human FcR. Moreover, a preferred FcR is one which binds an IgG antibody (a gamma receptor) and includes receptors of the FeyRI, FcyRII, and FcγRIII subclasses, including allelic variants and alternatively spliced forms of these receptors, FcyRTI receptors include FcγRIIA (an "activating receptor") and FcγRIIB (an "inhibiting receptor"), which have similar amino acid sequences that differ primarily in the cytoplasmic domains thereof. Activating receptor FcγRIIA contains an immunoreceptor tyrosine-based activation motif ("ITAM") in its cytoplasmic domain, Inhibiting receptor FcγRIIB contains an immunoreceptor tyrosine-based inhibition motif ("ITIM") in its cytoplasmic domain. Other FcRs, including those to be identified in the future, are encompassed by the term "FcR" herein. FcRs can also increase the serum half-life of antibodies. As used herein, "percent (%) amino acid sequence identity" and "homology" with respect to a peptide, polypeptide or antibody sequence refers to the percentage of amino acid residues in a candidate sequence that are identical with the amino acid residues in the specific peptide or polypeptide sequence, after aligning the sequences and introducing gaps, if necessary, to achieve the maximum percent sequence identity, and not considering any conservative substitutions as part of the sequence identity. Alignment for purposes of determining percent amino acid sequence identity can be achieved in various ways that are within the skill in the art, for instance, using publicly available computer software such as BLAST, BLAST-2, ALIGN or MEGALIGN ™< (DNASTAR) software. Those skilled in the art can determine appropriate parameters for measuring alignment, including any algorithms known in the art needed to achieve maximal alignment over the full length of the sequences being compared.

[0074] An "isolated" cell is a molecule or a cell that is identified and separated from at least one contaminant cell with which it is ordinarily associated in the environment in which it was produced. In some embodiments, the isolated cell is free of association with all components associated with the production environment. The isolated cell is in a form other than in the form or setting in which it is found in nature. Isolated cells are distinguished from cells existing naturally in tissues, organs, or individuals. In some embodiments, the isolated cell is a host cell of the present disclosure.

[0075] An "isolated" nucleic acid molecule encoding an antibody, such as an anti-Sortilin antibody of the present disclosure, is a nucleic acid molecule that is identified and separated from at least one contaminant nucleic acid molecule with which it is ordinarily associated in the environment in which it was produced. Preferably, the isolated nucleic acid is free of association with all components associated with the production environment. The isolated nucleic acid molecules encoding the polypeptides and antibodies herein is in a form other than in the form or setting in which it is found in nature. Isolated nucleic acid molecules therefore are distinguished from nucleic acid encoding the polypeptides and antibodies herein existing naturally in cells.

[0076] The term "vector," as used herein, is intended to refer to a nucleic acid molecule capable of transporting another nucleic acid to which it has been linked. One type of vector is a "plasmid," which refers to a circular double stranded DNA into which additional DNA segments may be ligated. Another type of vector is a phage vector. Another type of vector is a viral vector, wherein additional DNA segments may be ligated into the viral genome. Certain vectors are capable of autonomous replication in a host cell into which they are introduced (e.g., bacterial vectors having a bacterial origin of replication and episomal mammalian vectors). Other vectors (e.g., non-episomal mammalian vectors) can be integrated into the genome of a host cell upon introduction into the host cell, and thereby are replicated along with the host genome. Moreover, certain vectors are capable of directing the expression of genes to which they are operatively linked. Such vectors are referred to herein as "recombinant expression vectors," or simply, "expression vectors." In general, expression vectors of utility in recombinant DNA techniques are often in the form of plasmids. In the present specification, "plasmid" and "vector" may be used interchangeably as the plasmid is the most commonly used form of vector.

[0077] "Polynucleotide," or "nucleic acid," as used interchangeably herein, refer to polymers of nucleotides of any length, and include DNA and RNA. The nucleotides can be deoxyribonucleotides, ribonucleotides, modified nucleotides or bases, and / or their analogs, or any substrate that can be incorporated into a polymer by DNA or RNA polymerase or by a synthetic reaction.

[0078] A "host cell" includes an individual cell or cell culture that can be or has been a recipient for vector(s) for incorporation of polynucleotide inserts. Host cells include progeny of a single host cell, and the progeny may not necessarily be completely identical (in morphology or in genomic DNA complement) to the original parent cell due to natural, accidental, or deliberate mutation. A host cell includes cells transfected in vivo with a polynucleotide(s) of the present disclosure.

[0079] "Carriers" as used herein include pharmaceutically acceptable carriers, excipients, or stabilizers that are nontoxic to the cell or mammal being exposed thereto at the dosages and concentrations employed.

[0080] The term "about" as used herein refers to the usual error range for the respective value readily known to the skilled person in this technical field. Reference to "about" a value or parameter herein includes (and describes) embodiments that are directed to that value or parameter per se.

[0081] As used herein and in the appended claims, the singular forms "a," "an," and "the" include plural reference unless the context clearly indicates otherwise. For example, reference to an "antibody" is a reference to from one to many antibodies, such as molar amounts, and includes equivalents thereof known to those skilled in the art, and so forth.

[0082] It is understood that aspect and embodiments of the present disclosure described herein include "comprising," "consisting," and "consisting essentially of" aspects and embodiments.Overview

[0083] The present disclosure relates, in part, to anti-Sortilin antibodies that exhibit one or more improved and / or enhanced functional characteristics relative to an anti-Sortilin antibody, S-60, having a heavy chain variable region and a light chain variable region as described in WO2016164637. Nonlimiting improved and / or enhanced functional properties include, for example, antibodies capable of binding Sortilin with higher affinity, reducing cell surface levels of Sortilin, decreasing the half-maximal effective concentration (EC 50 ) to reduce cell surface levels of Sortilin, improving the maximal reduction of cell surface levels of Sortilin, increasing extracellular secretion of a Sortilin ligand: e.g Progranulin (PGRN), decreasing the half-maximal effective concentration (EC 50 ) to block PGRN binding to Sortilin, improving the maximal blocking of PGRN binding to Sortilin, or any combination thereof. Also contemplated herein are anti-Sortilin antibodies with different Fc variants that exhibit one or more improved and / or enhanced functional characteristics, including decreasing the half-maximal effective concentration (EC 50 ) to reduce cell surface levels of Sortilin, improving the maximal reduction of cell surface levels of Sortilin, increasing extracellular secretion of a Sortilin ligand: e.g Progranulin (PGRN), decreasing the half-maximal effective concentration (EC 50 ) to block PGRN binding to Sortilin, and improving the maximal blocking of PGRN binding to Sortilin.

[0084] In some embodiments, anti-Sortilin antibodies of the present disclosure have higher potencies in reducing cell surface levels of Sortilin relative to an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60. In some embodiments, potency is measured by half maximal effective concentration (EC 50 ) for reduction of cell surface cell levels of SORT !.

[0085] The present disclosure further relates to methods of making and using anti-Sortilin antibodies as described herein; pharmaceutical compositions containing such antibodies; nucleic acids encoding such antibodies; and host cells containing nucleic acids encoding such antibodies.

[0086] In some embodiments, the anti-Sortilin antibodies of the present disclosure may have one or more activities that are due, at least in part, to the ability of the antibodies to reduce levels (e.g., cell surface levels) of Sortilin by inducing degradation, down regulation, cleavage, receptor desensitization, and / or lysosomal targeting of Sortilin. In some embodiments, the anti-Sortilin antibodies exhibit one or more of the following properties: a. have a dissociation constant (K D ) for human Sortilin that is lower than that of an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60; b. decrease cell surface levels of Sortilin (e.g., decrease cell surface levels of Sortilin on engineered cells expressing human Sortilin in vitro) with a half-maximal effective concentration (EC 50 ) that is lower than that of an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60; c. have a dissociation constant (K D ) for human Sortilin that may range from about 0.560 nM to about 1.63 nM, for example when the K D is determined by fluorescent activated cell sorting (FACS); d. have a dissociation constant (K D ) for human Sortilin that may range from about 0.270 nM to about 2.910 nM, for example when the K D is determined by BioLayer Interferometry; c. decrease cell surface levels of Sortilin (e.g., decreases cell surface levels of Sortilin on engineered cells expressing human Sortilin in vitro) with a half-maximal effective concentration (EC 50 ) that may range from about 72.58 pM to about 103.6 pM, for example when the EC 50 is determined in vitro by FACS; f. reduce cell surface levels of Sortilin with a maximum reduction that may range from about 51.33% to 88.76%; g. increase extracellular secretion of PGRN higher than that of an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60; h. block PGRN binding to Sortilin (e.g., block binding of PGRN of Sortilin on engineered cells expressing human Sortilin in vitro) with a half-maximal effective concentration (EC 50 ) that may range from about .325 nM to about 2.27 nM, for example when the EC 50 is determined in vitro by FACS; and / or i. improve the maximal blocking of PGRN binding to Sortilin higher than that of an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60.

[0087] Advantageously, anti-Sortilin antibodies of the present disclosure reduce cell surface levels (e.g., up to approximately 3.02-fold) of Sortilin more potently (e.g., with a lower EC 50 ) as compared to a control anti-Sortilin antibody (e.g., a control anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60) (See e.g., Example 2). In some embodiments, anti-Sortilin antibodies of the present disclosure reduce binding of PGRN to Sortilin with a lower EC 50 (up to approximately 5.36 -fold) more potently as compared to a control anti-Sortilin antibody (e.g., a control anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60) (See e.g., Example 3 ). Moreover, advantageously, anti-Sortilin antibodies of the present disclosure have a higher affinity (e.g., up to approximately 2.79-fold higher affinity) for Sortilin (e.g., a lower K D value as measured by FACS or BioLayer Interferometry) as compared to a control anti-Sortilin antibody (e.g., a control anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60 (See e.g., Examples 1 and 4). Surprisingly, higher affinity for Sortilin does not necessarily correlate with an increase in ability or potency of reduction of cell surface levels of Sortilin (See, e.g., Examples 2 and 4) nor an increase in ability or potency of blocking binding of PGRN to Sortilin (See, e.g., Examples 3 and 4).

[0088] The present disclosure further relates to anti-Sortilin antibodies with improved stability during manufacturing, storage, and in vivo administration. In some embodiments, anti-Sortilin antibodies of the present disclosure have improved stability under various stress conditions (See, e.g.. Example 4). Sortilin proteins

[0089] In one aspect, the present disclosure provides antibodies, such as isolated (e.g., monoclonal) antibodies, that interact with or otherwise bind to a region, such as an epitope, within a Sortilin protein of the present disclosure. In some embodiments, the antibodies interact with or otherwise bind to a region, such as an epitope, within a Sortilin protein of the present disclosure with improved / enhanced kinetics (e.g., relative to an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, the antibodies interact with or otherwise bind to a region, such as an epitope, within a human Sortilin protein, with a half-maximal effective concentration (EC 50 ) that is lower than that of a control antibody (e.g., relative to an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a Sortilin protein and modulate one or more Sortilin activities after binding to the Sortilin protein, for example, an activity associated with Sortilin expression on a cell. Sortilin proteins of the present disclosure include, without limitation, a mammalian Sortilin protein, human Sortilin protein, mouse Sortilin protein, and rat Sortilin protein. Exemplary Sortilin protein sequences are shown in Table 32.

[0090] Sortilin is variously referred to as sortilin 1, SORT1, 100 kDa NT receptor, glycoprotein 95 (GP95), Progranulin receptor (PGRN-R), and neurotensin receptor 3 (NT-3 or NTR-3). Sortilin is an 831 amino acid protein that encodes a type I membrane receptor. Various Sortilin homologs are known, including without limitation, human Sortilin, rat Sortilin, and mouse Sortilin. The amino acid sequence of human Sortilin is set forth below as SEQ ID NO: 81 (with key amino acid residues predicted to participate in Progranulin binding depicted in bold and, and the predicted pro-NGF binding region underlined):

[0091] The amino acid sequence of mouse Sortilin is set forth in SEQ ID NO: 82:

[0092] The amino acid sequence of rat Sortilin is set forth in SEQ ID NO: 83:

[0093] In some embodiments, the Sortilin is a preprotein that includes a signal sequence. In some embodiments, the Sortilin is a mature protein. In some embodiments, the mature Sortilin protein does not include a signal sequence. In some embodiments, the mature Sortilin protein is expressed on a cell,

[0094] Sortilin proteins of the present disclosure include several domains, including without limitation, a signal sequence, a propeptide, a luminal domain, a Vps10p domain, a 10 CC domain, a transmembrane domain and a cytoplasmic domain. Additionally, proteins of the present disclosure are expressed at high levels in a number of tissues, including without limitation, the brain, spinal cord, heart and skeletal muscle, thyroid, placenta, and testis.

[0095] Accordingly, as used herein a "Sortilin" protein of the present disclosure includes, without limitation, a mammalian Sortilin protein, human Sortilin protein, primate Sortilin protein, mouse Sortilin protein, and rat Sortilin protein. Additionally, anti-Sortilin antibodies of the present disclosure may bind an epitope within one or more of a mammalian Sortilin protein, human Sortilin protein, primate Sortilin, mouse Sortilin protein, and rat Sortilin protein.Sortilin protein domains

[0096] Sortilin proteins of the present disclosure contain several domains, such as a Vps10p domain that contains an Asp-box motif, a ten-bladed beta-propeller structure, and a hydrophobic loop; and a 10 CC domain.

[0097] As disclosed herein, interactions between Sortilin proteins of the present disclosure and pro-neurotrophins or neurotrophins are mediated by the Vps10p domain that contains a ten-bladed beta-propeller structure and an Asp-box motif. In certain embodiments, Sortilin proteins of the present disclosure contain a Vps10 domain that includes a ten-bladed beta-propeller structure and is located within amino acid residues 78-611 of human Sortilin (SEQ ID NO: 81) or amino acid residues of a mammalian Sortilin that correspond to amino acid residues 78-611 of SEQ ID NO: 81. In certain embodiments, amino acid residues 190-220 of human Sortilin (SEQ ID NO: 81) or amino acid residues of a mammalian Sortilin that correspond to amino acid residues 190-220 of SEQ ID NO: 81 are located within the Vps10p domain.

[0098] Vps10p domains of the present disclosure may include an Asp-box motif: As used herein, Asp-box motifs have the following sequence: (S / T)-X-(D / N)-X-X-X-X-(W / F / Y) (SEQ ID NO: 84), or X-X-(S / T)-X-(D / N)-X-G-X-(T / S)-(W / F / Y)-X (SEQ ID NO: 85), where X represents any amino acid. In human Sortilin, the Asp-box motif is SSDFAKNF (SEQ ID NO:86), located at amino acid residues 200-207 of human Sortilin. Accordingly, in certain embodiments, an Asp-box motif is located at amino acid residues 200-207 of human Sortilin (SEQ ID NO: 81) or amino acid residues of a mammalian Sortilin that correspond to amino acid residues 200-207 of SEQ ID NO: 81.

[0099] As disclosed herein, interactions between Sortilin proteins of the present disclosure and p75 are mediated by the 10CC domain of the hydrophobic loop of the Vps10p domain.

[0100] In certain embodiments, Sortilin proteins of the present disclosure contain a 10CC domain that is located within amino acid residues 610-757 of human Sortilin (SEQ ID NO: 81) or amino acid residues of a mammalian Sortilin that correspond to amino acid residues 610-757 of SEQ ID NO: 81. In preferred embodiments, amino acid residues 592-593, 610-660, and / or 667-749 of human Sortilin (SEQ ID NO: 81) or amino acid residues of a mammalian Sortilin that correspond to amino acid residues 592-593, 610-660, and / or 667-749 of SEQ ID NO: 81 are located within the 10CC domain of Sortilin.

[0101] In other embodiments, Sortilin proteins of the present disclosure contain a hydrophobic loop within the Vps10p domain that is located within amino acid residues 130-141 of human Sortilin (SEQ ID NO: 81) or amino acid residues of a mammalian Sortilin that correspond to amino acid residues 130-141 of SEQ ID NO: 81.

[0102] As one of skill in the art will appreciate, the beginning and ending residues of the domains of the present disclosure may vary depending upon the computer modeling program used or the method used for determining the domain.Sortilin binding partners

[0103] Sortilin proteins of the present disclosure can interact with (e.g., bind to) one or more proteins including, without limitation, Progranulin (PGRN) protein; neurotrophins, such as pro-neurotrophins, pro-neurotrophin-3, neurotrophin-3, pro-neurotrophin-4 / 5, neurotrophin-4 / 5, pro-nerve growth factor (Pro-NGF), nerve growth factor (NGF), pro-brain-derived neurotrophic factor (Pro-BDNF), and brain-derived neurotrophic factor (BDNF); neurotensin, p75, lipoprotein lipase (LpL), apolipoprotein AV (APOA5), apolipoprotein E (APOE), amyloid precursor protein, A beta peptide, PCSK9, p75NTR, and receptor associated protein (RAP).Progranulin (PGRN)

[0104] Sortilin proteins of the present disclosure have been shown to interact (e.g., bind to) directly with Progranulin and mediate the degradation of Progranulin (e.g., Zheng, Y et al., (2011) PLoS ONE 6(6): e21023).

[0105] Progranulin is variously referred to as PGRN, proepithelin, granulin-epithelin precursor, PC (prostate cancer) cell-derived growth factor (PCDGF), and acrogranin. Progranulin is a 593 amino acid protein that encodes a 68.5 kD a secreted glycoprotein that has 7.5 repeats of smaller granulin (epithelin) motifs, ranging from 6-25 kDa, which can be proteolytically cleaved from the precursor PGRN. Examples of Progranulin cleavage products include, without limitation, granulin A / Epithelins 1, granulin B Epithelins 2, granulin C, granulins D, granulin E, granulin F, granulin G and any other known peptide products derived from Progranulin.

[0106] Accordingly, anti-Sortilin antibodies of the present disclosure that increase Progranulin levels, decrease cell surface levels of Sortilin, and / or block the interaction (e.g., binding) between Sortilin and Progranulin would be beneficial for preventing, lowering the risk of, or treating conditions and / or diseases associated with decreased levels of Progranulin expression and / or activity, cell death (e.g., neuronal cell death), frontotemporal dementia, Alzheimer's disease, vascular dementia, seizures, retinal dystrophy, a traumatic brain injury, a spinal cord injury, long-term depression, atherosclerotic vascular diseases, undesirable symptoms of normal aging, dementia, mixed dementia, Creutzfeldt-Jakob disease, normal pressure hydrocephalus, amyotrophic lateral sclerosis, Huntington's disease, taupathy disease, stroke, acute trauma, chronic trauma, lupus, acute and chronic colitis, Crohn's disease, inflammatory bowel disease, ulcerative colitis, malaria, essential tremor, central nervous system lupus, Behcet's disease, Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, intervertebral disc degeneration, Shy-Drager syndrome, progressive supranuclear palsy, cortical basal ganglionic degeneration, acute disseminated encephalomyelitis, granulomartous disorders, Sarcoidosis, diseases of aging, age related macular degeneration, glaucoma, retinitis pigmentosa, retinal degeneration, respiratory tract infection, sepsis, eye infection, systemic infection, inflammatory disorders, arthritis, multiple sclerosis, metabolic disorder, obesity, insulin resistance, type 2 diabetes, tissue or vascular damage, an injury, and / or one or more undesirable symptoms of normal aging. Additionally, anti-Sortilin antibodies of the present disclosure that increase Progranulin levels, decrease cell surface levels of Sortilin, and / or block the interaction (e.g., binding) between Sortilin and Progranulin may inhibit interaction between Sortilin and Progranulin, may induce one or more Progranulin activities, may reduce the endosomal internalization of Progranulin, or fragments thereof, and / or may increase the effective concentration of Progranulin.

[0107] In some embodiments, anti-Sortilin antibodies of the present disclosure that increase Progranulin levels, decrease cell surface levels of Sortilin, and / or block the interaction (e.g., binding) between Sortilin and Progranulin bind to one or more amino acids within amino acid residues 131-138, 175-181, 190-220, 199-220, 190-211, 196-207, 196-199, 200-207, 203-207, 207-231, 207-227, 212-221, 233-243, 237-247, 237-260, 297-317, 314-338, 367-391, 429-443, 623-632, and / or 740-749 of human Sortilin (SEQ ID NO: 81); or within amino acid residues of a mammalian Sortilin that corresponds to amino acid residues 131-138, 175-181, 190-220, 199-220, 190-211, 196-207, 196-199, 200-207, 203-207, 207-231, 207-227, 212-221, 233-243, 237-247, 237-260, 297-317, 314-338, 367-391, 429-443, 623-632, and / or 740-749 of SEQ ID NO: 81. In other embodiments, anti-Sortilin antibodies of the present disclosure that increase Progranulin levels, decrease cell surface levels of Sortilin, and / or block the interaction (e.g., binding) between Sortilin and Progranulin may bind one or more amino acids of amino acid residues His131, Val132, Prol33, Leul34, Val135, Ile136, Met137, Thr138, Arg196, Phel98, Arg199, Phe203, Lys205, Phe207, Thr210, Thr218. Tyr222, Ser223, Ser227, Ser242, Lys243, Lys248, Lys254, Lys260, Ser305, Phe306, Gly307, Arg311, Phe314, Ser316, Arg325, Arg326, Ile327, Phe350,Tyr351, Ser352, Ile353, Asn373, Ser379, Arg382, Tyr386, Ser595, and / or Glu700 of human Sortilin (SEQ ID NO: 81); or of amino acid residues of a mammalian Sortilin that corresponds to one or more amino acid residues His131, Val132, Pro133, Leu134, Val135, Ile136, Met137, Thrl38, Arg196, Phe198, Arg199, Phe203, Lys205, Phe207, Thr210, Thr218, Tyr222, Ser223, Ser227, Ser242, Lys243, Lys248, Lys254, Lys260, Ser305, Phe306, Gly307, Arg311, Phe314, Ser316, Arg325, Arg326, Ile327, Phe350;Tyr351, Ser352, Ile353, Asn373, Ser379, Arg382, Tyr386, Ser595, and / or Glu700 of SEQ ID NO: 81.Other Sortilin Ligands

[0108] Sortilin proteins of the present disclosure have been shown to interact (e.g., bind) directly with pro-neurotrophins (e.g., pro-NGF), which harbor a pro-domain and are typically pro-apoptotic. This binding may be mediated through a linear epitope on Sortilin that corresponds to amino acid residues 163-174 of SEQ ID NO: 81. Sortilin proteins of the present disclosure also have been shown to interact (e.g., bind) with neurotensin within the beta-propeller structure of Sortilin, and an important contact has been shown to at serine 283 of human Sortilin.

[0109] Sortilin proteins of the present disclosure have also been shown to interact (e.g., bind) with the low affinity nerve growth factor (NGF) receptor (p75) within the 10CC domain of Sortilin or the hydrophobic loop of the Vps10p domain of Sortilin. As disclosed herein, Sortilin proteins of the present disclosure can function as a co-receptor with p75 for pro-neurotrophins, which induce apoptotic signaling. Sortilin proteins of the present disclosure have further been shown to interact (e.g., bind) with amyloid precursor protein (APP).

[0110] Sortilin proteins of the present disclosure have been shown to interact (e.g., bind) with the lipoprotein lipase (LpL). As disclosed herein, Sortilin proteins of the present disclosure bind to and modify the degradation of LpL. Sortilin proteins of the present disclosure have been shown to interact (e.g., bind) with the apolipoprotein AV (APOA5). As disclosed herein, Sortilin proteins of the present disclosure bind to and modify the degradation of APOA5.

[0111] Sortilin proteins of the present disclosure have been shown to interact (e.g., bind) with the apolipoprotein E (APOE, APOE2, APOE3, APOE4). As disclosed herein, Sortilin proteins of the present disclosure bind to and modify the degradation and transport of APOE as well as agents that APOE carries such as the A beta peptide. In addition, Sortilin proteins of the present disclosure have been shown to interact (e.g., bind) with receptor-associate protein (RAP). Further, Sortilin proteins of the present disclosure have been shown to interact (e.g., bind) with Proprotein convertase subtilisin / kexin type 9 (PCSK9), and secrete it to the circulation.

[0112] In some embodiments of any of the anti-Sortilin antibodies, anti-Sortilin antibodies of the present disclosure may also inhibit (e.g., block) the interaction between Sortilin and one or more other Sortilin ligands of the present disclosure. In some embodiments, the one or more other ligands is one or more of pro-neurotrophins, neurotensin, low affinity nerve growth factor (NGF) receptor (p75), amyloid precursor protein, lipoprotein lipase, apolipoprotein AV, apolipoprotein, receptor-associated protein, and / or proprotein convertase subtilisin / kexin type 9. Such antibodies may be beneficial for preventing, lowering the risk of, or treating conditions and / or diseases associated with decreased levels of one or more other Sortilin ligands expression and / or activity, cell death (e.g., neuronal cell death). In some embodiments, the one or more other ligands is one or more of pro-neurotrophins, neurotensin, low affinity nerve growth factor (NGF) receptor (p75), amyloid precursor protein, lipoprotein lipase, apolipoprotein AV, apolipoprotein, receptor-associated protein, and / or proprotein convertase subtilisin / kexin type 9.

[0113] Anti-Sortilin antibodies of the present disclosure that inhibit (e.g., block) the interaction between Sortilin and one or more other Sortilin ligands of the present disclosure may also prevent cell death (e.g., apoptosis) induced by one or more other Sortilin ligands. In some embodiments, the one or more other ligands is one or more of pro-neurotrophins, neurotensin, low affinity nerve growth factor (NGF) receptor (p75), amyloid precursor protein, lipoprotein lipase, apolipoprotein AV, apolipoprotein, receptor-associated protein, and / or proprotein convertase subtilisin / kexin type 9.

[0114] In some embodiments of any of the anti-Sortilin antibodies, anti-Sortilin antibodies of the present disclosure that inhibit (e.g., block) the interaction between Sortilin and one or more Sortilin ligands of the present disclosure bind one or more amino acids within amino acid residues within amino acid residues 131-138, 175-181, 190-220, 199-220, 190-211, 196-207, 196-199, 200-207, 203-207, 207-231, 207-227, 212-221, 233-243, 237-247, 237-260, 297-317, 314-338, 367-391, 429-443, 623-632, and / or 740-749 of human Sortilin (SEQ ID NO: 81); or within amino acid residues of a mammalian Sortilin that corresponds to amino acid residues 131-138, 175-181, 190-220, 199-220, 190-211, 196-207, 196-199, 200-207, 203-207, 207-231, 207-227, 212-221, 233-243, 237-247, 237-260, 297-317, 314-338, 367-391, 429-443, 623-632, and / or 740-749 of SEQ ID NO: 81. In some embodiments, the one or more other ligands is one or more of pro-neurotrophins, neurotensin, low affinity nerve growth factor (NGF) receptor (p75), amyloid precursor protein, lipoprotein lipase, apolipoprotein AV, apolipoprotein, receptor-associated protein, and / or proprotein convertase subtilisin / kexin type 9.

[0115] In other embodiments of any of the anti-Sortilin antibodies, anti-Sortilin antibodies of the present disclosure that inhibit (e.g., block) the interaction between Sortilin and one or more Sortilin ligands of the present disclosure bind one or more amino acids of amino acid residues His131, Val132, Pro133, Leu134, Val135, Ile136, Met137, Thr138, Arg196, Phel98, Arg199, Phe203, Lys205, Phe207, Thr210, Thr218, Tyr222, Ser223, Ser227, Ser242, Lys243, Lys248, Lys254, Lys260, Ser305, Phe306, Gly307, Arg311, Phe314, Ser316, Arg325, Arg326, Ile327, Phe350,Tyr351, Ser352, Ile353, Asn373, Ser379, Arg382, Tyr386, Ser595, and / or Glu700 of human Sortilin (SEQ ID NO: 81); or of amino acid residues of a mammalian Sortilin that corresponds to one or more amino acid residues His131, Val132, Pro133, Leu134, Val135, Ile136, Met137, Thr138, Arg196, Phel98, Arg199, Phe203, Lys205, Phe207, Thr210, Thr218, Tyr222, Ser223, Ser227, Ser242, Lys243, Lys248, Lys254, Lys260, Ser305, Phe306, Gly307, Arg311, Phe314, Ser316, Arg325, Arg326, Ile327, Phe350,Tyr351, Ser352, Ile353, Asn373, Ser379, Arg382, Tyr386, Ser595, and / or Glu700 of SEQ ID NO: 81. In some embodiments, the one or more other ligands is one or more of pro-neurotrophins, neurotensin, low affinity nerve growth factor (NGF) receptor (p75), amyloid precursor protein, lipoprotein lipase, apolipoprotein AV, apolipoprotein, receptor-associated protein, and / or proprotein convertase subtilisin / kexin type 9.Sortilin antibodies

[0116] Certain aspects of the present disclosure relate to anti-Sortilin antibodies comprising one or more improved and / or enhanced functional characteristics. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise one or more improved and / or enhanced functional characteristics relative to an anti-Sortilin antibody, S-60, having a heavy chain variable region and a light chain variable region as described in WO2016164637. In some embodiments, anti-Sortilin antibodies of the present disclosure have an affinity for Sortilin (e.g., human Sortilin) that is higher than that of a control anti-Sortilin antibody (e.g., a control anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure decrease cellular levels (e.g., cell surface levels) of Sortilin to a greater degree and with a half-maximal effective concentration (EC50) that is lower than that of a control antibody (e.g., a control anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure improve the maximal reduction of cell surface levels of Sortilin relative to an anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60. In some embodiments, anti-Sortilin antibodies of the present disclosure increase the secretion of extracellular Progranulin (PGRN) relative to an anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60. In some embodiments, anti-Sortilin antibodies of the present disclosure blocking binding of PGRN to Sortilin to a greater degree and with a half-maximal effective concentration (EC50) that is lower than that of a control antibody (e.g., a control anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure improve the maximal blocking of PGRN binding to Sortilin relative to an anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60.

[0117] Also contemplated herein are anti-Sortilin antibodies with different Fc variants that exhibit one or more improved and / or enhanced functional characteristics relative to an anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60, including decreasing the half-maximal effective concentration (EC50) to reduce cell surface levels of Sortilin, improving the maximal reduction of cell surface levels of Sortilin, increasing extracellular secretion of PGRN, decreasing the half-maximal effective concentration (EC50) to block PGRN binding to Sortilin, and improving the maximal blocking of PGRN binding to Sortilin,

[0118] In some embodiments, an anti-Sortilin antibody of the present disclosure is a human antibody, a bispecific antibody, a monoclonal antibody, a multivalent antibody, a conjugated antibody, or a chimeric antibody

[0119] In a preferred embodiment, an anti-Sortilin antibody of the present disclosure is a monoclonal antibody.Anti-Sortilin antibody binding, epitope

[0120] In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a Sortilin protein of the present disclosure and / or naturally occurring variants. In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a Sortilin protein, wherein the Sortilin protein is a human protein. In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a Sortilin protein, wherein the Sortilin protein is a wild-type protein. In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a Sortilin protein, wherein the Sortilin protein is a naturally occurring variant.

[0121] In certain preferred embodiments, anti-Sortilin antibodies of the present disclosure bind specifically to a human Sortilin protein.

[0122] Certain aspects of the present disclosure provide anti-Sortilin antibodies that bind a discontinuous Sortilin epitope. In some embodiments, the discontinuous Sortilin epitope comprises two or more peptides, three or more peptides, four or more peptides, five or more peptides, six or more peptides, seven or more peptide, eight or more peptides, nine or more peptides, or 10 or more peptides. In some embodiments, each of the peptides comprise five or more, six or more, seven or more, eight or more, nine or more, 10 or more, 11 or more, 12 or more, 13 or more 14 or more, 15 or more, 16 or more, 17 or more, 18 or more, 19 or more, 20 or more, 21 or more, 22 or more, 23 or more, 24 or more, 25 or more, 26 or more, 27 or more, 28 or more, 29 or more, or 30 or more amino acid residues of the amino acid sequence of SEQ ID NO: 81; or five or more, six or more, seven or more, eight or more, nine or more, 10 or more, 11 or more, 12 or more, 13 or more 14 or more, 15 or more, 16 or more, 17 or more, 18 or more, 19 or more, 20 or more, 21 or more, 22 or more, 23 or more, 24 or more, 25 or more, 26 or more, 27 or more, 28 or more, 29 or more, or 30 or more amino acid residues on a mammalian Sortilin protein corresponding to the amino acid sequence of SEQ ID NO: 81. Other aspects of the present disclosure provide anti-Sortilin antibodies that bind to a conformational epitope of Sortilin.

[0123] Certain aspects of the present disclosure provide anti-Sortilin antibodies that bind to one or more amino acids within amino acid residues 207-231 of human Sortilin (SEQ ID NO: 81); or within amino acid residues on a mammalian Sortilin corresponding to amino acid residues 207-231 of SEQ ID NO: 81. In some embodiments, the anti-Sortilin antibodies bind to one or more amino acids of amino acid residues Thr218, Tyr222, Ser223, and / or Ser227 of human Sortilin (SEQ ID NO: 81); or of amino acid residues on a mammalian Sortilin corresponding to amino acid residues Thr218, Tyr222, Ser223, and / or Ser227 of SEQ ID NO: 81. In some embodiments, the anti-Sortilin antibodies bind to one or more amino acids of amino acid residues F105, L108, R109, G110, 1537, F569, E590, F592, L593, S595, and / or W597 of human Sortilin (SEQ ID NO: 81); or of amino acid residues on a mammalian Sortilin corresponding to amino acid residues F105, L108, R109, G110, I537, F569, E590, F592, L593, S595, and / or W597 of SEQ ID NO: 81. Other aspects of the present disclosure provide anti-Sortilin antibodies that bind to an epitope having amino acid residues (S / T)-X-(D / N)-X-X-X-X-(W / F / Y), where X represents any amino acid (SEQ ID NO: 84).

[0124] In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a Sortilin protein of the present disclosure expressed on the surface of cell and the naked antibodies inhibit interaction (e.g., binding) between the Sortilin protein and a protein selected from Progranulin (PGRN), a pro-neurotrophin, a neurotrophin, pro-neurotrophin-3, neurotrophin-3, pro-neurotrophin-4 / 5, neurotrophin-4 / 5, pro-nerve growth factor (pro-NGF), nerve growth factor (NGF), pro-brain-derived neurotrophic factor (pro-BDNF), brain-derived neurotrophic factor (BDNF), neurotensin, p75, Sortilin propeptide (Sort-pro), amyloid precursor protein (APP), the A beta peptide, lipoprotein lipase (LpL), apolipoprotein AV (APOA5), apolipoprotein E (APOE), PCSK9, and receptor associated protein (RAP). In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a Sortilin protein of the present disclosure expressed on the surface of cell and the naked antibodies inhibit interaction (e.g., binding) between the Sortilin protein and PGRN.

[0125] In some embodiments, anti-Sortilin antibodies of the present disclosure that bind to a Sortilin protein of the present disclosure inhibit interaction (e.g., binding) between the Sortilin protein and Progranulin, a pro-neurotrophin, a neurotrophin, pro-neurotrophin-3, neurotrophin-3, pro-neurotrophin-4 / 5, neurotrophin-4 / 5, pro-nerve growth factor (pro-NGF), nerve growth factor (NGF), pro-brain-derived neurotrophic factor (pro-BDNF), brain-derived neurotrophic factor (BDNF), neurotensin, p75, Sortilin propeptide (Sort-pro), amyloid precursor protein (APP), the A beta peptide, lipoprotein lipase (LpL), apolipoprotein AV (APOA5), apolipoprotein E (APOE), PCSK9, and receptor associated protein (RAP) by reducing the effective levels of Sortilin that is available to interact with these proteins either on the cell surface or inside the cell.

[0126] In some embodiments, anti-Sortilin antibodies of the present disclosure that bind to a Sortilin protein of the present disclosure inhibit interaction (e.g., binding) between the Sortilin protein and Progranulin, a pro-neurotrophin, a neurotrophin, pro-neurotrophin-3, neurotrophin-3, pro-neurotrophin-4 / 5, neurotrophin-4 / 5, pro-nerve growth factor (pro-NGF), nerve growth factor (NGF), pro-brain-derived neurotrophic factor (pro-BDNF), brain-derived neurotrophic factor (BDNF), neurotensin, p75, Sortilin propeptide (Sort-pro), amyloid precursor protein (APP), the A beta peptide, lipoprotein lipase (LpL), apolipoprotein AV (APOA5), apolipoprotein E (APOE), PCSK9, and receptor associated protein (RAP) by inducing degradation of Sortilin.

[0127] In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a human Sortilin, or a homolog thereof, including without limitation, a mammalian Sortilin protein, or a non-human primate Sortilin protein. In some embodiments, anti-Sortilin antibodies of the present disclosure specifically bind to human Sortilin. In some embodiments, anti-Sortilin antibodies of the present disclosure bind to human Sortilin and are not cross-reactive with Sortilin orthologs or homologs from other species.Anti-Sortilin antibody competitive binding

[0128] In some embodiments, anti-Sortilin antibodies of the present disclosure competitively inhibit binding of at least one other anti-Sortilin antibody selected from any of the antibodies listed in Tables 1-29. In some embodiments, anti-Sortilin antibodies of the present disclosure competitively inhibit binding of at least one antibody selected from: S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24; and any combination thereof.

[0129] In some embodiments, an anti-Sortilin antibody of the present disclosure competes with one or more anti-Sortilin antibodies selected from: S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-1 1, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24 and any combination thereof, for binding to Sortilin when the anti-Sortilin antibody reduces the binding of one or more antibodies selected from: S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24; and any combination thereof to Sortilin by an amount the ranges from about 50% to 100%, as compared to binding to Sortilin in the absence of the anti-Sortilin antibody.

[0130] In some embodiments, an anti-Sortilin antibody of the present disclosure competes with one or more anti-Sortilin antibodies selected from: S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, and any combination thereof, for binding to Sortilin when the anti-Sortilin antibody reduces the binding of one or more antibodies selected from: S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N331], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24; and any combination thereof to Sortilin by at least 50%, at least 55%, by at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, or 100%, as compared to binding to Sortilin in the absence of the anti-Sortilin antibody.

[0131] In some embodiments, an anti-Sortilin antibody of the present disclosure that reduces the binding of one or more antibodies selected from: S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, and any combination thereof, to Sortilin by 100% indicates that the anti-Sortilin antibody essential completely blocks the binding of one or more antibodies selected from S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, and any combination thereof, to Sortilin. In some embodiments, the anti-Sortilin antibody and the one or more antibodies selected from S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-1 1, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, and any combination thereof, are present in an amount that corresponds to a 10:1 ratio, 9:1 ratio, 8:1 ratio, 7:1 ratio, 6:1 ratio, 5:1 ratio, 4:1 ratio, 3:1 ratio, 2:1 ratio, 1:1 ratio, 0.75:1 ratio, 0.5:1 ratio, 0.25:1 ratio, 0.1:1 ratio, 0.075:1 ratio, 0.050:1 ratio, 0.025:1 ratio, 0.01:1 ratio, 0.0075: ratio, 0.0050:1 ratio, 0.0025:1 ratio, 0.001: ratio, 0.00075:1 ratio, 0.00050:1 ratio, 0.00025:1 ratio, 0.0001: ratio, 1:10 ratio, 1:9 ratio, 1:8 ratio, 1:7 ratio, 1:6 ratio, 1:5 ratio, 1:4 ratio, 1:3 ratio, 1:2 ratio, 1:0.75 ratio, 1:0.5 ratio, 1:0.25 ratio, 1:0.1 ratio, 1:0.075 ratio, 1:0.050 ratio, 1:0.025 ratio, 1:0.01 ratio, 1:0.0075 ratio, 1:0.0050 ratio, 1:0.0025 ratio, 1:0.001 ratio, 1:0.00075 ratio, 1 :0.00050 ratio, 1:0.00025 ratio, or 1:0.0001 ratio of anti-Sortilin antibody to one or more antibodies selected from S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, and any combination thereof. In some embodiments, the anti-Sortilin antibody is present in excess by an amount that ranges from about 1.5-fold to 100-fold, or greater than 100-fold compared to the amount of the one or more antibodies selected from S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N331], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, and any combination thereof. In some embodiments, the anti-Sortilin antibody is present in an amount that is about a 2-fold, 3-fold, 4-fold, 5-fold, 6-fold, 7-fold, 8-fold, 9-fold, 10-fold, 15-fold, 20-fold, 25-fold, 30-fold, 35-fold, 40-fold, 45-fold, 50-fold, 55-fold, 60-fold, 65-fold, 70-fold, 75-fold, 80-fold, 85-fold, 90-fold, 95-fold, or 100-fold excess compared to the amount of the one or more antibodies selected from S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, and any combination thereof.

[0132] In some embodiments, anti-Sortilin antibodies of the present disclosure bind to an epitope of human Sortilin that is the same as or overlaps with the Sortilin epitope bound by at least one antibody selected from any of the antibodies listed in Tables 1-29. In some embodiments, anti-Sortilin antibodies of the present disclosure bind to an epitope of human Sortilin that is the same as or overlaps with the Sortilin epitope bound by at least one antibody selected from: S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.1 1 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24; and any combination thereof. In some embodiments, anti-Sortilin antibodies of the present disclosure bind essentially the same Sortilin epitope bound by at least one antibody selected from any of the antibodies listed in Tables 1-29. In some embodiments, anti-Sortilin antibodies of the present disclosure bind essentially the same Sortilin epitope bound by at least one antibody selected from: S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.1 1 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24; and any combination thereof. Detailed exemplary methods for mapping an epitope to which an antibody binds are provided in Morris (1996) "Epitope Mapping Protocols," in Methods in Molecular Biology vol. 66 (Humana Press, Totowa, NJ).

[0133] Any suitable competition assay or Sortilin binding assay known in the art, such as BIAcore analysis, ELISA assays, or flow cytometry, may be utilized to determine whether an anti-Sortilin antibody competes with one or more antibodies selected from: S-60, S-60-1, S-60-2, S-60-3, S-60-4, S-60-5, S-60-6, S-60-7, S-60-8, and S-60-9 (described in WO2016164637); or S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], $-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24; and any combination thereof for binding to Sortilin. In an exemplary competition assay, immobilized Sortilin or cells expressing Sortilin on the cell surface are incubated in a solution comprising a first labeled antibody that binds to Sortilin (e.g., human or non-human primate) and a second unlabeled antibody that is being tested for its ability to compete with the first antibody for binding to Sortilin. The second antibody may be present in a hybridoma supernatant. As a control, immobilized Sortilin or cells expressing Sortilin is incubated in a solution comprising the first labeled antibody but not the second unlabeled antibody. After incubation under conditions permissive for binding of the first antibody to Sortilin, excess unbound antibody is removed, and the amount of label associated with immobilized Sortilin or cells expressing Sortilin is measured. If the amount of label associated with immobilized Sortilin or cells expressing Sortilin is substantially reduced in the test sample relative to the control sample, then that indicates that the second antibody is competing with the first antibody for binding to Sortilin. See, Harlow and Lane (1988) Antibodies: A Laboratory Manual ch. 14 (Cold Spring Harbor Laboratory, Cold Spring Harbor, NY).

[0134] In some embodiments, an anti-Sortilin antibody of the present disclosure competes with an antibody comprising the heavy chain variable domain and the light chain variable domain of an antibody selected from the group consisting of S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-16, S-60-18, S-60-19, S-60-24, and any combination thereof for binding to Sortilin.

[0135] In some embodiments, an anti-Sortilin antibody of the present disclosure binds essentially the same Sortilin epitope as an antibody comprising the heavy chain variable domain and the light chain variable domain of an antibody selected from the group consisting of S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-16, S-60-18, S-60-19, and S-60-24.

[0136] Additional anti-Sortilin antibodies, e.g., antibodies that specifically bind to a Sortilin protein of the present disclosure, may be identified, screened, and / or characterized for their physical / chemical properties and / or biological activities by various assays known in the art.Anti-Sortilin antibody heavy chain and light chain variable regionsA. Heavy chain HVRs

[0137] In some embodiments, anti-Sortilin antibodies of the present disclosure include a heavy chain variable region comprising one or more (e.g., one or more, two or more, or all three) HVRs selected from HVR-H1, HVR-H2, and HVR-H3 (as shown in Tables 14-16). In some embodiments, the heavy chain variable region comprises an HVR-H1, an HVR-H2, and an HVR-H3 (as shown in Tables 14-16).

[0138] In some embodiments, the HVR-H1 comprises a sequence of YSISSGYYWG (SEQ ID NO: 1). In some embodiments, the HVR-H2 comprises a sequence according to Formula I: TIYHSGSTYYNPSLX 1 S (SEQ ID NO: 4), wherein X 1 is K or E. In some embodiments, the HVR-H2 comprises a sequence selected from SEQ ID NOs: 2-3. In some embodiments, the HVR-H3 comprises a sequence according to Formula II: ARQGSIX 1 QGYYGMDV (SEQ ID NO: 7). In some embodiments, the HVR-H3 comprises a sequence selected from SEQ ID NOs: 5-6.

[0139] In some embodiments, the HVR-H1 comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence of SEQ ID NO: 1. In some embodiments, the HVR-H1 comprises an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence of SEQ ID NO: 1), but retains the ability to bind to Sortilin. In certain embodiments, up to 1, up to 2, up to 3, up to 4, or up to 5 amino acids been substituted, inserted, and / or deleted in the HVR-H1 amino acid sequence of SEQ ID NO: 1. In some embodiments, the HVR-H2 comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence selected from SEQ ID NOs: 2-3. In some embodiments, the HVR-H2 comprises an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence selected from SEQ ID NOs: 2-3), but retains the ability to bind to Sortilin. In certain embodiments, up to 1, up to 2, up to 3, up to 4, or up to 5 amino acids been substituted, inserted, and / or deleted in the HVR-H2 amino acid sequence selected from SEQ ID NOs: 2-3. In some embodiments, the HVR-H3 comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence selected from SEQ ID NOs: 5-6. In some embodiments, the HVR-H3 comprises an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence selected from SEQ ID NOs: 5-6), but retains the ability to bind to Sortilin. In certain embodiments, up to 1, up to 2, up to 3, up to 4, or up to 5 amino acids been substituted, inserted, and / or deleted in the HVR-H3 amino acid sequence selected from SEQ ID NOs: 5-6.

[0140] In some embodiments, the heavy chain variable region comprises an HVR-H1 comprising a sequence of YSISSGYYWG (SEQ ID NO: 1), an HVR-H2 comprising a sequence according to Formula I, and an HVR-H3 comprising a sequence according to Formula II.

[0141] In some embodiments, the heavy chain variable region comprises an HVR-H1 comprising a sequence of SEQ ID NO: 1, an HVR-H2 comprising a sequence selected from SEQ ID NOs: 2-3, and an HVR-H3 comprising a sequence selected from SEQ ID NOs: 5-6.

[0142] In some embodiments, the heavy chain variable region comprises the HVR-H1 HVR-H2, and HVR-H3 of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, or any combination thereof (as shown in Tables 14-16).

[0143] In some embodiments, anti-Sortilin antibodies of the present disclosure include a heavy chain variable region, wherein the heavy chain variable region comprises one or more of: (a) an HVR-H1 comprising an amino acid sequence with at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-H1 amino acid sequence of antibody S-60-10, S-60-1 1, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24; (b) an HVR-H2 comprising an amino acid sequence with at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-H2 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24; and (c) an HVR-H3 comprising an amino acid sequence with at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-H3 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15, 11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N331], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24.

[0144] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise an HVR-H1 comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), an HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLKS (SEQ ID NO: 2), and an HVR-H3 comprising the amino acid sequence ARQGSIKQGYYGMDV (SEQ ID NO: 6).B. Light chain HVRs

[0145] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable region comprising one or more (e.g., one or more, two or more, or all three) HVRs selected from HVR-L1, HVR-L2, and HVR-L3 (as shown in Tables 17-19). In some embodiments, the light chain variable region comprises an HVR-L1, an HVR-L2, and an HVR-L3 (as shown in Tables 17-19 ).

[0146] In some embodiments, the HVR-L1 comprises a sequence according to Formula III: RSSQX 1 LLX 2 SX 3 GYNYLD (SEQ ID NO: 28), wherein X 1 is S or G, X 2 is R or H, and X 3 is N, T, S, G, R, D, H, K, Q, Y, E, W, F, I, V, A, M, or L. In some embodiments, the HVR-L1 comprises a sequence selected from SEQ ID NOs: 8-27. In some embodiments, the HVR-L1 comprises a sequence of RSSQSLLRSNGYNYLD (SEQ ID NO:8). RSSQSLLRSTGYNYLD (SEQ ID NO:9), RSSQS LLRSSGYNYLD (SEQ ID NO:10), RSSQSLLRSGGYNYLD (SEQ ID NO:11), RSSQSLLRSRG YNYLD (SEQ ID NO: 12), RSSQSLLRSDGYNYLD (SEQ ID NO: 13), RSSQSLLRSHGYNYLD (SEQ ID NO: 14), RSSQSLLRSKGYNYLD (SEQ ID NO: 15), RSSQSLLRSQGYNYLD (SEQ ID NO:16), RSSQSLLRSYGYNYLD (SEQ ID NO:17), RSSQSLLRSEGYNYLD (SEQ ID NO:18), RSSQSLLRSWGYNYLD (SEQ ID NO:19), RSSQSLLRSEGYNYLD (SEQ ID NO:20), RSSQSL LRSIGYNYLD (SEQ ID NO:21), RSSQSLLRSVGYNYLD (SEQ ID NO:22), RSSQSLLRSAG YNYLD (SEQ ID NO:23), RSSQSLLRSMGYNYLD (SEQ ID NO:24), RSSQSLLRSEGYNYLD (SEQ ID NO:25), RSSQSLLHSNGYNYLD (SEQ ID NO:26), or RSSQGLLRSNGYNYLD (SEQ ID NO:27). In one specific embodiment, the HVR-L1 comprises a sequence of RSSQSLLRSNGYNYLD (SEQ ID NO:8). In another specific embodiment, the HVR-L1 comprises a sequence of RSSQSLLRSTGYNYLD (SEQ ID NO:9) (as shown in Table 19 ).

[0147] In some embodiments, the HVR-L2 comprises a sequence according to Formula IV: LGSNRX1S (SEQ ID NO: 31), wherein X1 is A or V. In some embodiments, the HVR-L2 comprises a sequence selected from SEQ ID NOs: 29-30.

[0148] In some embodiments, the HVR-L3 comprises a sequence according to Formula V: MQQQEX1PLT (SEQ ID NO: 34), wherein X1 is A or T. In some embodiments, the HVR-L3 comprises a sequence selected from SEQ ID NOs: 32-33.

[0149] In some embodiments, the HVR-L1 comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence selected from SEQ ID NOs: 8-27. In some embodiments, the HVR-L1 comprises an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence selected from SEQ ID NOs: 8-27), but retains the ability to bind to Sortilin. In certain embodiments, up to 1, up to 2, up to 3, up to 4, or up to 5 amino acids been substituted, inserted, and / or deleted in the HVR-L1 amino acid sequence selected from SEQ ID NOs: 8-27, In some embodiments, the HVR-L2 comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence selected from SEQ ID NOs: 29-30. In some embodiments, the HVR-L2 comprises an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence selected from SEQ ID NOs: 29-30), but retains the ability to bind to Sortilin. In certain embodiments, up to 1, up to 2, up to 3, up to 4, or up to 5 amino acids been substituted, inserted, and / or deleted in the HVR-L2 amino acid sequence selected from SEQ ID NOs: 29-30. In some embodiments, the HVR-L3 comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence selected from SEQ ID NOs: 32-33. In some embodiments, the HVR-L3 comprises an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence selected from SEQ ID NOs: 32-33), but retains the ability to bind to Sortilin. In certain embodiments, up to 1, up to 2, up to 3, up to 4, or up to 5 amino acids been substituted, inserted, and / or deleted in the HVR-L3 amino acid sequence selected from SEQ ID NOs: 32-33.

[0150] In some embodiments, the light chain variable region comprises an HVR-L1 comprising a sequence according to Formula III, an HVR-L2 comprising a sequence according to Formula IV, and an HVR-L3 comprising a sequence according to Formula V. In some embodiments, the light chain variable region comprises an HVR-L1 comprising a sequence selected from SEQ ID NOs: 8-27, an HVR-L2 comprising a sequence selected from SEQ ID NOs: 29-30, and an HVR-L3 comprising a sequence selected from SEQ ID NOs: 32-33.

[0151] In some embodiments, the light chain variable region comprises the HVR-L1, HVR-L2, and HVR-L3 of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N331], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, or any combination thereof (as shown in Tables 17-19).

[0152] In some embodiments, anti-Sortilin antibodies of the present disclosure include a light chain variable region, wherein the light chain variable region comprises one or more of: (a) an HVR-L1 comprising an amino acid sequence with at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-L1 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33YJ, S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24; (b) an HVR-L2 comprising an amino acid sequence with at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-L2 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N331], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24; and (c) an HVR-L3 comprising an amino acid sequence with at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-L3 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24.

[0153] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise an HVR-L1 comprising the amino acid sequence RSSQSLLRSNGYNYLD (SEQ ID NO: 8), an HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and an HVR-L3 comprising the amino acid sequence MQQQEAPLT (SEQ ID NO: 32).

[0154] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise an HVR-Ll comprising the amino acid sequence RSSQSLLRSTGYNYLD (SEQ ID NO: 9), an HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and an HVR-L3 comprising the amino acid sequence MQQQEAPLT (SEQ ID NO: 32).C. Heavy chain HVRs and light chain HVRs

[0155] In some embodiments, anti-Sortilin antibodies of the present disclosure include a heavy chain variable region comprising one or more (e.g., one or more, two or more, or all three) HVRs selected from HVR-H1, HVR-H2, and HVR-H3 (as shown in Tables 14-16), and a light chain variable region comprising one or more (e.g., one or more, two or more, or all three) HVRs selected from HVR-L1, HVR-L2, and HVR-L3 (as shown in Tables 17-19). In some embodiments, the heavy chain variable region comprises an HVR-H1, an HVR-H2, and an HVR-H3 (as shown in Tables 14-16), and the light chain variable region comprises an HVR-L1, an HVR-L2, and an HVR-L3 (as shown in tables Tables 17-19).

[0156] In some embodiments, the heavy chain variable region comprises an HVR-111 comprising a sequence of YSISSGYYWG (SEQ ID NO: 1), an HVR-H2 comprising a sequence according to Formula I, and an HVR-H3 comprising a sequence according to Formula II, and the light chain variable region comprises an HVR-L1 comprising a sequence according to Formula III, an HVR-L2 comprising a sequence according to Formula IV, and an HVR-L3 comprising a sequence according to Formula V. In some embodiments, the heavy chain variable region comprises an HVR-H1 comprising a sequence of SEQ ID NO: 1, an HVR-H2 comprising a sequence selected from SEQ ID NOs: 2-3, and an HVR-H3 comprising a sequence selected from SEQ ID NOs: 5-6, and the light chain variable region comprises an HVR-L1 comprising a sequence selected from SEQ ID NOs: 8-27, an HVR-L2 comprising a sequence selected from SEQ ID NOs: 29-30, and an HVR-L3 comprising a sequence selected from SEQ ID NOs: 32-33.

[0157] In some aspects, the heavy chain variable region comprises an HVR-H1 comprising a sequence of SEQ ID NO: 1, an HVR-H2 comprising a sequence selected from SEQ ID NOs: 2-3, and an HVR-H3 comprising a sequence selected from SEQ ID NOs: 5-6, and the light chain variable region comprises an HVR-L1 comprising a sequence selected from SEQ ID NOs: 8-27, an HVR-L2 comprising a sequence selected from SEQ ID NOs: 29-30, and an HVR-L3 comprising a sequence of SEQ ID NO: 32.

[0158] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region comprising the HVR-H1, HVR-H2, and HVR-H3 of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, or any combination thereof (as shown in Tables 14-16); and a light chain variable region comprising the HVR-L1, HVR-L2, and HVR-L3 of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, S-60-24, or any combination thereof (as shown in Tables 17-19).

[0159] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region comprising an HVR-H1, HVR-H2, and HVR-H3 and a light chain variable region comprising an HVR-L1, HVR-L2, and HVR-L3, wherein the antibody comprises the HVR-H1, HVR-H2, HVR-H3, HVR-L1, HVR-L2, and HVR-L3 of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24 (as shown in Tables 14-19).

[0160] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region comprises one or more of (a) an HVR-H1 comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-H1 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24; (b) an HVR-H2 comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%), at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-H2 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24; and (c) an HVR-H3 comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-H3 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24; and wherein the light chain variable region comprises one or more of: (a) an HVR-L1 comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%), at least 98%, at least 99%, or 100% identity to an HVR-L1 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.1 1 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24; (b) an HVR-L2 comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-L2 amino acid sequence of antibody S-60-10, S-60-1 1, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D), S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24; and (c) an HVR-L3 comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to an HVR-L3 amino acid sequence of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24,

[0161] In some embodiments, an anti-Sortilin antibody of the present disclosure comprises a heavy chain variable region comprising the HVR-H1 comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), the HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLKS (SEQ ID NO: 2), the HVR-H3 comprising the amino acid sequence ARQGSIQQGYYGMDV (SEQ ID NO: 5); and a light chain variable region comprising the HVR-L1 comprising the amino acid sequence RSSQSLLRSNGYNYLD (SEQ ID NO: 8), the HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and the HVR-L3 comprising the amino acid sequence MQQQEAPLT (SEQ ID NO: 32).

[0162] In some embodiments, an anti-Sortilin antibody of the present disclosure comprises a heavy chain variable region comprising the HVR-H1 comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), the HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLKS (SEQ ID NO: 2), the HVR-H3 comprising the amino acid sequence ARQGSIQQGYYGMDV (SEQ ID NO: 5); and a light chain variable region comprising the HVR-L1 comprising the amino acid sequence RSSQSLLRSNGYNYLD (SEQ ID NO: 8), the HVR-L2 comprising the amino acid sequence LGSNRVS (SEQ ID NO: 30), and the HVR-L3 comprising the amino acid sequence MQQQETPLT (SEQ ID NO: 33).

[0163] In some embodiments, an anti-Sortilin antibody of the present disclosure comprises a heavy chain variable region comprising the HVR-H1 comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), the HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLES (SEQ ID NO: 3), the HVR-H3 comprising the amino acid sequence ARQGSIQQGYYGMDV (SEQ ID NO: 5); and a light chain variable region comprising the HVR-L1 comprising the amino acid sequence RSSQSLLRSNGYNYLD (SEQ ID NO: 8), the HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and the HVR-L3 comprising the amino acid sequence MQQQEAPLT (SEQ ID NO: 32).

[0164] In some aspects, an anti-Sortilin antibody of the present disclosure comprises a heavy chain variable region comprising the HVR-H1 comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), the HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLKS (SEQ ID NO: 2), the HVR-H3 comprising the amino acid sequence ARQGSIKQGYYGMDV (SEQ ID NO: 6); and a light chain variable region comprising the HVR-L1 comprising the amino acid sequence RSSQSLLRSNGYNYLD (SEQ ID NO: 8), the HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and the HVR-L3 comprising the amino acid sequence MQQQEAPLT (SEQ ID NO: 32).

[0165] In some aspects, an anti-Sortilin antibody of the present disclosure comprises a heavy chain variable region comprising the HVR-H1 comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), the HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLKS (SEQ ID NO: 2), the HVR-H3 comprising the amino acid sequence ARQGSIKQGYYGMDV (SEQ ID NO: 6); and a light chain variable region comprising the HVR-L1 comprising the amino acid sequence RSSQSLLRSTGYNYLD (SEQ ID NO: 9), the HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and the HVR-L3 comprising the amino acid sequence MQQQEAPLT (SEQ ID NO: 32).

[0166] In some embodiments, an anti-Sortilin antibody of the present disclosure comprises a heavy chain variable region comprising the HVR-H1 comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), the HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLKS (SEQ ID NO: 2), the HVR-H3 comprising the amino acid sequence ARQGSIKQGYYGMDV (SEQ ID NO: 6); and a light chain variable region comprising the HVR-L1 comprising the amino acid sequence RSSQSLLRSNGYNYLD (SEQ ID NO: 8), the HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and the HVR-L3 comprising the amino acid sequence MQQQETPLT (SEQ ID NO: 33).

[0167] In some embodiments, an anti-Sortilin antibody of the present disclosure comprises a heavy chain variable region comprising the HVR-N1. comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), the HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLKS (SEQ ID NO: 2), the HVR-H3 comprising the amino acid sequence ARQGSIQQGYYGMDV (SEQ ID NO: 5); and a light chain variable region comprising the HVR-L1 comprising the amino acid sequence RSSQSLLHSNGYNYLD (SEQ ID NO: 26), the HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and the HVR-L3 comprising the amino acid sequence MQQQETPLT (SEQ ID NO: 33).

[0168] In some embodiments, an anti-Sortilin antibody of the present disclosure comprises a heavy chain variable region comprising the HVR-H1 comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), the HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLKS (SEQ ID NO: 2), the HVR-H3 comprising the amino acid sequence ARQGSIKQGYYGMDV (SEQ ID NO: 6); and a light chain variable region comprising the HVR-L1 comprising the amino acid sequence RSSQGLLRSNGYNYLD (SEQ ID NO: 27), the HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and the HVR-L3 comprising the amino acid sequence MQQQEAPLT (SEQ ID NO: 32).D. Heavy chain variable region

[0169] In some embodiments, anti-Sortilin antibodies of the present disclosure include a heavy chain variable region comprising an amino acid sequence selected from SEQ ID NOs: 54-56. In some embodiments, the heavy chain variable region comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence selected from SEQ ID NOs: 54-56. In some embodiments, the heavy chain variable region comprises an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence selected from SEQ ID NOs: 54-56), but retains the ability to bind to Sortilin. In certain embodiments, up to 1, up to 2, up to 3, up to 4, up to 5, up to 6, up to 7, up to 8, up to 9, or up to 10 amino acids been substituted, inserted, and / or deleted in the heavy chain variable region amino acid sequence selected from SEQ ID NOs: 54-56.

[0170] In some embodiments, the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 56.

[0171] In some embodiments, anti-Sortilin antibodies of the present disclosure include a heavy chain variable region of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24 (as shown in Table 30).

[0172] In some embodiments, anti-Sortilin antibodies of the present disclosure include a heavy chain variable region comprising an HVR-H1 comprising the amino acid sequence YSISSGYYWG (SEQ ID NO: 1), an HVR-H2 comprising the amino acid sequence TIYHSGSTYYNPSLKS (SEQ ID NO: 2), and an HVR-H3 comprising the amino acid sequence ARQGSIKQGYYGMDV (SEQ ID NO: 6).E. Light chain variable region

[0173] In some embodiments, anti-Sortilin antibodies of the present disclosure include a light chain variable region comprising an amino acid sequence selected from SEQ ID NOs: 57-80. In some embodiments, the light chain variable region comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence selected from SEQ ID NOs: 57-80. In some embodiments, the light chain variable region comprises an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence selected from SEQ ID NOs: 57-80), but retains the ability to bind to Sortilin. In certain embodiments, up to 1, up to 2, up to 3, up to 4, up to 5, up to 6, up to 7, up to 8, up to 9, or up to 10 amino acids been substituted, inserted, and / or deleted in the light chain variable region amino acid sequence selected from SEQ ID NOs: 57-80.

[0174] In some embodiments, the light chain variable region includes the amino acid sequence of SEQ ID NO: 57. In some embodiments, the light chain variable region includes the amino acid sequence of SEQ ID NO: 60.

[0175] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable region of antibody S-60-10, S-60-1 1, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33QJ, S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N331], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24 (as shown in Table 31).

[0176] In some embodiments, anti-Sortilin antibodies of the present disclosure include a light chain variable region comprising an HVR-L1 comprising the amino acid sequence RSSQSLLRSNGYNYLD (SEQ ID NO: 8), an HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and an HVR-L3 comprising the amino acid sequence MQQQEAPLT (SEQ ID NO: 32).

[0177] In some embodiments, anti-Sortilin antibodies of the present disclosure include a light chain variable region comprising an HVR-L 1 comprising the amino acid sequence RSSQSLLRSTGYNYLD (SEQ ID NO: 9), an HVR-L2 comprising the amino acid sequence LGSNRAS (SEQ ID NO: 29), and an HVR-L3 comprising the amino acid sequence MQQQEAPLT (SEQ ID NO: 32).F. Heavy chain variable region and light chain variable region

[0178] In some aspects, an anti-Sortilin antibody of the present disclosure includes a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 54-56; and / or a light chain variable region comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 57-80. In some embodiments, the heavy chain variable region comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence selected from SEQ ID NOs: 54-56, and the light chain variable region comprises an amino acid sequence with at least about 90%, at least about 91%, at least about 92%, at least about 93%, at least about 94%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or 100% identity to an amino acid sequence selected from SEQ ID NOs: 57-80 . In some embodiments, an anti-Sortilin antibody of the present disclosure includes a heavy chain variable region comprising an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence selected from SEQ ID NOs: 54-56), and a light chain variable region comprising an amino acid sequence containing substitutions (e.g., conservative substitutions, insertions, or deletions relative to an amino acid sequence selected from SEQ ID NOs: 57-80), but retains the ability to bind to Sortilin. In certain embodiments, up to 1, up to 2, up to 3, up to 4, up to 5, up to 6, up to 7, up to 8, up to 9, or up to 10 amino acids been substituted, inserted, and / or deleted in the heavy chain variable region amino acid sequence selected from SEQ ID NOs: 54-56; and up to 1, up to 2, up to 3, up to 4, up to 5, up to 6, up to 7, up to 8, up to 9, or up to 10 amino acids been substituted, inserted, and / or deleted in the light chain variable region amino acid sequence selected from SEQ ID NOs: 57-80.

[0179] In some aspects, an anti-Sortilin antibody of the present disclosure includes a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 54-56; and / or a light chain variable region comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 57-58, 60-78, and 80.

[0180] In some embodiments, an anti-Sortilin antibody of the present disclosure binds to a Sortilin protein, wherein the antibody includes a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 54, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 57; a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 54, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 58; a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 54, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 59; a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 55, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 57; a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 55, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 58; a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 56, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 57; a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 56, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 77; a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 56, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 78; a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 54, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 79; or a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 56, and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 80.

[0181] In one aspect, an anti-Sortilin antibody of the present disclosure includes a heavy chain variable region having the amino acid sequence of SEQ ID NO: 56, and a light chain variable region having the amino acid sequence of SEQ ID NO: 57.

[0182] In one aspect, an anti-Sortilin antibody of the present disclosure includes a heavy chain variable region having the amino acid sequence of SEQ ID NO: 56, and a light chain variable region having the amino acid sequence of SEQ ID NO: 60.

[0183] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24 (as shown in Table 30), and a light chain variable region of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24 (as shown in Table 31).

[0184] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 56, and a light chain variable region comprising an amino acid sequence selected from SEQ ID NOs: 56 and 60. In some embodiments, the antibody comprises a heavy chain variable region of S-60-15 [N33 (wt)] (as shown in Table 30), and a light chain variable region of antibody S-60-15 [N33 (wt)] (as shown in Table 31). In some embodiments, the antibody comprises a heavy chain variable region of S-60-15.1 [N33T] (as shown in Table 30), and a light chain variable region of antibody S-60-15.1 [N33T] (as shown in Table 31). Exemplary anti-Sortilin antibodies

[0185] In some embodiments, the anti-Sortilin antibody is an anti-Sortilin monoclonal antibody comprising the heavy chain variable region and the light chain variable region of an antibody selected from S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24. In some embodiments, the anti-Sortilin antibody is an anti-Sortilin monoclonal antibody comprising the heavy chain and the light chain of an antibody selected from S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N335], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24.(1) S-60-10

[0186] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-10 or to the amino acid sequence of SEQ ID NO: 54; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-10 or to the amino acid sequence of SEQ ID NO: 57. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-10 or to the amino acid sequence of SEQ ID NO: 54, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-10. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-10 or to the amino acid sequence of SEQ ID NO: 57, wherein the light chain variable domain comprises the HVR-L1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-10. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-10 or to the amino acid sequence of SEQ ID NO: 54 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-10 or the amino acid sequence of SEQ ID NO: 54. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-10 or the amino acid sequence of SEQ ID NO: 54. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-10 or of SEQ ID NO: 54, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-10, (b) the HVR-H2 amino acid sequence of antibody S-60-10, and (c) the HVR-H3 amino acid sequence of antibody S-60-10. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-10 or to the amino acid sequence of SEQ ID NO: 57 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-10 or the amino acid sequence of SEQ ID NO: 57. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-10 or the amino acid sequence of SEQ ID NO: 57. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-10 or of SEQ ID NO: 57, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-10, (b) the HVR-L2 amino acid sequence of antibody S-60-10, and (c) the HVR-L3 amino acid sequence of antibody S-60-10.

[0187] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 105 or SEQ ID NO: 106. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 139. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 105 or SEQ ID NO: 106 and a light chain comprising the amino acid sequence of SEQ ID NO: 139.(2) S-60-11

[0188] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-11 or to the amino acid sequence of SEQ ID NO: 54; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-11 or to the amino acid sequence of SEQ ID NO: 58. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%), or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-11 or to the amino acid sequence of SEQ ID NO: 54, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-1 1. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-11 or to the amino acid sequence of SEQ ID NO: 58, wherein the light chain variable domain comprises the HVR-L 1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-11. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-11 or to the amino acid sequence of SEQ ID NO: 54 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-11 or the amino acid sequence of SEQ ID NO: 54. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-11 or the amino acid sequence of SEQ ID NO: 54. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-1 1 or of SEQ ID NO: 54, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-1 1, (b) the HVR-H2 amino acid sequence of antibody S-60-11, and (c) the HVR-H3 amino acid sequence of antibody S-60-1 1. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%), or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-11 or to the amino acid sequence of SEQ ID NO: 58 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-1 1 or the amino acid sequence of SEQ ID NO: 58. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-11 or the amino acid sequence of SEQ ID NO: 58. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-11 or of SEQ ID NO: 58, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-11, (b) the HVR-L2 amino acid sequence of antibody S-60-11, and (c) the HVR-L3 amino acid sequence of antibody S-60-11.

[0189] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 105 or SEQ ID NO: 106. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 140. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 105 or SEQ ID NO: 106 and a light chain comprising the amino acid sequence of SEQ ID NO: 140.(3) S-60-12

[0190] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100%, identity to a heavy chain variable domain amino acid sequence of antibody S-60-12 or to the amino acid sequence of SEQ ID NO: 54; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity, to a light chain variable domain amino acid sequence of antibody S-60-12 or to the amino acid sequence of SEQ ID NO: 59. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-12 or to the amino acid sequence of SEQ ID NO: 54, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-12. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-12 or to the amino acid sequence of SEQ ID NO: 59, wherein the light chain variable domain comprises the HVR-L1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-12. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-12 or to the amino acid sequence of SEQ ID NO: 54 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-12 or the amino acid sequence of SEQ ID NO: 54. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-12 or the amino acid sequence of SEQ ID NO: 54. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions), In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-12 or of SEQ ID NO: 54, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-12, (b) the HVR-H2 amino acid sequence of antibody S-60-12, and (c) the HVR-H3 amino acid sequence of antibody S-60-12. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-12 or to the amino acid sequence of SEQ ID NO: 59 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-12 or the amino acid sequence of SEQ ID NO: 59. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-12 or the amino acid sequence of SEQ ID NO: 59. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-12 or of SEQ ID NO: 59, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-12, (b) the HVR-L2 amino acid sequence of antibody S-60-12, and (c) the HVR-L3 amino acid sequence of antibody S-60-12.

[0191] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 105 or SEQ ID NO: 106. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 141. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 105 or SEQ ID NO: 106 and a light chain comprising the amino acid sequence of SEQ ID NO: 141.(4) S-60-13

[0192] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-13 or to the amino acid sequence of SEQ ID NO: 55; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-13 or to the amino acid sequence of SEQ ID NO: 57. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-13 or to the amino acid sequence of SEQ ID NO: 55, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-13. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-13 or to the amino acid sequence of SEQ ID NO: 57, wherein the light chain variable domain comprises the HVR-L1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-13. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-13 or to the amino acid sequence of SEQ ID NO: 55 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-13 or the amino acid sequence of SEQ ID NO: 55. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-13 or the amino acid sequence of SEQ ID NO: 55. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-13 or of SEQ ID NO: 55, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-13, (b) the HVR-H2 amino acid sequence of antibody S-60-13, and (c) the HVR-H3 amino acid sequence of antibody S-60-13. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-13 or to the amino acid sequence of SEQ ID NO: 57 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-13 or the amino acid sequence of SEQ ID NO: 57. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-13 or the amino acid sequence of SEQ ID NO: 57. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-13 or of SEQ ID NO: 57, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-13, (b) the HVR-L2 amino acid sequence of antibody S-60-13, and (c) the HVR-L3 amino acid sequence of antibody S-60-13.

[0193] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 135 or SEQ ID NO: 136. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 139. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 135 or SEQ ID NO: 136 and a light chain comprising the amino acid sequence of SEQ ID NO: 139.(5) S-60-14

[0194] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-14 or to the amino acid sequence of SEQ ID NO: 55; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-14 or to the amino acid sequence of SEQ ID NO: 58. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-14 or to the amino acid sequence of SEQ ID NO: 55, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-14. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-14 or to the amino acid sequence of SEQ ID NO: 58, wherein the light chain variable domain comprises the HVR-L 1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-14. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%), at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-14 or to the amino acid sequence of SEQ ID NO: 55 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-14 or the amino acid sequence of SEQ ID NO: 55. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-14 or the amino acid sequence of SEQ ID NO: 55. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-14 or of SEQ ID NO: 55, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-14, (b) the HVR-H2 amino acid sequence of antibody S-60-14, and (c) the HVR-H3 amino acid sequence of antibody S-60-14. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-14 or to the amino acid sequence of SEQ ID NO: 58 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-14 or the amino acid sequence of SEQ ID NO: 58. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-14 or the amino acid sequence of SEQ ID NO: 58. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-14 or of SEQ ID NO: 58, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-14, (b) the HVR-L2 amino acid sequence of antibody S-60-14, and (c) the HVR-L3 amino acid sequence of antibody S-60-14.

[0195] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 135 or SEQ ID NO: 136. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 140. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 135 or SEQ ID NO: 136 and a light chain comprising the amino acid sequence of SEQ ID NO: 140.(6) S-60-15

[0196] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-15 or to the amino acid sequence of SEQ ID NO: 56; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-15 or to the amino acid sequence of SEQ ID NO: 57. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-15 or to the amino acid sequence of SEQ ID NO: 56, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-15. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-15 or to the amino acid sequence of SEQ ID NO: 57, wherein the light chain variable domain comprises the HVR-L1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-15. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-15 or to the amino acid sequence of SEQ ID NO: 56 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-15 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-15 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-15 or of SEQ ID NO: 56, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-15, (b) the HVR-H2 amino acid sequence of antibody S-60-15, and (c) the HVR-H3 amino acid sequence of antibody S-60-15. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-15 or to the amino acid sequence of SEQ ID NO: 57 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-15 or the amino acid sequence of SEQ ID NO: 57. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-15 or the amino acid sequence of SEQ ID NO: 57. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-15 or of SEQ ID NO: 57, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-15, (b) the HVR-L2 amino acid sequence of antibody S-60-15, and (c) the HVR-L3 amino acid sequence of antibody S-60-15.

[0197] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 139. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138 and a light chain comprising the amino acid sequence of SEQ ID NO: 139.(7) S-60-15.1

[0198] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-15.1 or to the amino acid sequence of SEQ ID NO: 56; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-15.1 or to the amino acid sequence of SEQ ID NO: 60. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-15.1 or to the amino acid sequence of SEQ ID NO: 56, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-15.1. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-15.1 or to the amino acid sequence of SEQ ID NO: 60, wherein the light chain variable domain comprises the HVR-L1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-15.1. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-15.1 or to the amino acid sequence of SEQ ID NO: 56 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-15.1 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-15.1 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-15.1 or of SEQ ID NO: 56, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-N1 amino acid sequence of antibody S-60-15.1, (b) the HVR-H2 amino acid sequence of antibody S-60-15.1, and (c) the HVR-H3 amino acid sequence of antibody S-60-15.1. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-15.1 or to the amino acid sequence of SEQ ID NO: 60 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-15.1 or the amino acid sequence of SEQ ID NO: 60. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-15.1 or the amino acid sequence of SEQ ID NO: 60. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-15.1 or of SEQ ID NO: 60, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-15.1, (b) the HVR-L2 amino acid sequence of antibody S-60-15.1, and (c) the HVR-L3 amino acid sequence of antibody S-60-15.1.

[0199] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 142. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138 and a light chain comprising the amino acid sequence of SEQ ID NO: 142.(8) S-60-16

[0200] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-16 or to the amino acid sequence of SEQ ID NO: 56; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-16 or to the amino acid sequence of SEQ ID NO: 77. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-16 or to the amino acid sequence of SEQ ID NO: 56, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-16. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-16 or to the amino acid sequence of SEQ ID NO: 77, wherein the light chain variable domain comprises the HVR-L1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-16. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-16 or to the amino acid sequence of SEQ ID NO: 56 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-16 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-16 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-16 or of SEQ ID NO: 56, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-16, (b) the HVR-H2 amino acid sequence of antibody S-60-16, and (c) the HVR-H3 amino acid sequence of antibody 5-60-16, In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-16 or to the amino acid sequence of SEQ ID NO: 77 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-16 or the amino acid sequence of SEQ ID NO: 77. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-16 or the amino acid sequence of SEQ ID NO: 77. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-16 or of SEQ ID NO: 77, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-16, (b) the HVR-L2 amino acid sequence of antibody S-60-16, and (c) the HVR-L3 amino acid sequence of antibody S-60-16.

[0201] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 131. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138 and a light chain comprising the amino acid sequence of SEQ ID NO: 131.(9) S-60-18

[0202] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-18 or to the amino acid sequence of SEQ ID NO: 56; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-18 or to the amino acid sequence of SEQ ID NO: 78. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-18 or to the amino acid sequence of SEQ ID NO: 56, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-18. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-18 or to the amino acid sequence of SEQ ID NO: 78, wherein the light chain variable domain comprises the HVR-L1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-18. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-18 or to the amino acid sequence of SEQ ID NO: 56 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-18 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-18 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-18 or of SEQ ID NO: 56, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-18, (b) the HVR-H2 amino acid sequence of antibody S-60-18, and (c) the HVR-H3 amino acid sequence of antibody S-60-18. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-18 or to the amino acid sequence of SEQ ID NO: 78 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-18 or the amino acid sequence of SEQ ID NO: 78. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-18 or the amino acid sequence of SEQ ID NO: 78. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-18 or of SEQ ID NO: 78, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-18, (b) the HVR-L2 amino acid sequence of antibody S-60-18, and (c) the HVR-L3 amino acid sequence of antibody S-60-18.

[0203] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 132. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138 and a light chain comprising the amino acid sequence of SEQ ID NO: 132.(10) S-60-19

[0204] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-19 or to the amino acid sequence of SEQ ID NO: 54; and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 1 00% identity to a light chain variable domain amino acid sequence of antibody S-60-19 or to the amino acid sequence of SEQ ID NO: 79. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-19 or to the amino acid sequence of SEQ ID NO: 54, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-19. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-19 or to the amino acid sequence of SEQ ID NO: 79, wherein the light chain variable domain comprises the HVR-L1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-19. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-19 or to the amino acid sequence of SEQ ID NO: 54 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-19 or the amino acid sequence of SEQ ID NO: 54. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-19 or the amino acid sequence of SEQ ID NO: 54. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-19 or of SEQ ID NO: 54, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-19, (b) the HVR-H2 amino acid sequence of antibody S-60-19, and (c) the HVR-H3 amino acid sequence of antibody S-60-19. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-19 or to the amino acid sequence of SEQ ID NO: 79 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-19 or the amino acid sequence of SEQ ID NO: 79. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-19 or the amino acid sequence of SEQ ID NO: 79. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-19 or of SEQ ID NO: 79, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-19, (b) the HVR-L2 amino acid sequence of antibody S-60-19, and (c) the HVR-L3 amino acid sequence of antibody S-60-19.

[0205] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 105 or SEQ ID NO: 106. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 133. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 105 or SEQ ID NO: 106 and a light chain comprising the amino acid sequence of SEQ ID NO: 133.(11) S-60-24

[0206] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain and a light chain variable domain, wherein the heavy chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-24 or to the amino acid sequence of SEQ ID NO: 56: and / or the light chain variable domain comprises an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-24 or to the amino acid sequence of SEQ ID NO: 80. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-24 or to the amino acid sequence of SEQ ID NO: 56, wherein the heavy chain variable domain comprises the HVR-H1, HVR-H2, and HVR-H3 amino acid sequences of antibody S-60-24. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain comprising an amino acid sequence with at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-24 or to the amino acid sequence of SEQ ID NO: 80, wherein the light chain variable domain comprises the HVR-L1, HVR-L2, and HVR-L3 amino acid sequences of antibody S-60-24. In some embodiments, the anti-Sortilin antibody comprises a heavy chain variable domain (VH) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a heavy chain variable domain amino acid sequence of antibody S-60-24 or to the amino acid sequence of SEQ ID NO: 56 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-24 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the heavy chain variable domain amino acid sequence of antibody S-60-24 or the amino acid sequence of SEQ ID NO: 56. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VH sequence of antibody S-60-24 or of SEQ ID NO: 56, including post-translational modifications of that sequence. In a particular embodiment, the VH comprises one, two or three HVRs selected from: (a) the HVR-H1 amino acid sequence of antibody S-60-24, (b) the HVR-H2 amino acid sequence of antibody S-60-24, and (c) the HVR-H3 amino acid sequence of antibody S-60-24. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable domain (VL) sequence having at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identity to a light chain variable domain amino acid sequence of antibody S-60-24 or to the amino acid sequence of SEQ ID NO: 80 and contains substitutions (e.g., conservative substitutions, insertions, or deletions relative to the reference sequence), but the anti-Sortilin antibody comprising that sequence retains the ability to bind to Sortilin. In certain embodiments, a total of 1 to 10 amino acids have been substituted, inserted, and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-24 or the amino acid sequence of SEQ ID NO: 80. In certain embodiments, a total of 1 to 5 amino acids have been substituted, inserted and / or deleted in the light chain variable domain amino acid sequence of antibody S-60-24 or the amino acid sequence of SEQ ID NO: 80. In certain embodiments, substitutions, insertions, or deletions occur in regions outside the HVRs (i.e., in the FR regions). In some embodiments, the substitutions, insertions, or deletions occur in in the FR regions. Optionally, the anti-Sortilin antibody comprises the VL sequence of antibody S-60-24 or of SEQ ID NO: 80, including post-translational modifications of that sequence. In a particular embodiment, the VL comprises one, two or three HVRs selected from: (a) the HVR-L1 amino acid sequence of antibody S-60-24, (b) the HVR-L2 amino acid sequence of antibody S-60-24, and (c) the HVR-L3 amino acid sequence of antibody S-60-24.

[0207] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain comprising the amino acid sequence of SEQ ID NO: 134. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 or SEQ ID NO: 138 and a light chain comprising the amino acid sequence of SEQ ID NO: 134.

[0208] In some embodiments, an anti-Sortilin antibody of the present disclosure binds essentially the same Sortilin epitope as an antibody comprising the heavy chain variable domain and the light chain variable domain of an antibody selected from the group consisting of S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-16, S-60-18, S-60-19, and S-60-24.

[0209] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-10. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-10. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-10. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-10. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-10.

[0210] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-11. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-11. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-1 1. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-1 1. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-11.

[0211] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-12. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-12. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-12. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-12. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-12.

[0212] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-13. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-13. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-13. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-13. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-13.

[0213] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-14. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-14. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-14. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-14. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-14.

[0214] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-15. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-15. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-15. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-15. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-15.

[0215] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-15.1. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-15.1. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-15.1. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-15.1. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-15.1.

[0216] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-16. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-16. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-16. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-16. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-16.

[0217] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-18. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-18. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-18. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-18. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-1 8.

[0218] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-19. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-19. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-19. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-19. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-19.

[0219] In some embodiments, the anti-Sortilin antibody is anti-Sortilin monoclonal antibody S-60-24. In some embodiments, the anti-Sortilin antibody is an isolated antibody which binds essentially the same Sortilin epitope as S-60-24. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region of monoclonal antibody S-60-24. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the light chain variable region of monoclonal antibody S-60-24. In some embodiments, the anti-Sortilin antibody is an isolated antibody comprising the heavy chain variable region and the light chain variable region of monoclonal antibody S-60-24.

[0220] In certain embodiments, the anti-Sortilin antibody is an antagonist antibody. In certain embodiments, the anti-Sortilin antibody is an agonist antibody. In some embodiments, anti-Sortilin antibodies of the present disclosure are of the IgG class the IgM class, or the IgA class. In some embodiments, anti-Sortilin antibodies of the present disclosure are of the IgG class and have an IgG1, IgG2, IgG3, or IgG4 isotype.

[0221] Additional anti-Sortilinantibodies, e.g., antibodies that specifically bind to a Sortilin protein of the present disclosure, may be identified, screened, and / or characterized for their physical / chemical properties and / or biological activities by various assays known in the art.

[0222] Certain aspects of the present disclosure relate to the use of two or more anti-Sortilin antibodies that when utilized together display additive or synergistic effects, as compared to utilization of a corresponding single anti-Sortilin antibody.

[0223] In some embodiments, an anti-Sortilin antibody of the present disclosure is an antibody fragment that binds to a human Sortilin protein.

[0224] In some embodiments, an anti-Sortilin antibody of the present disclosure is an antibody fragment that binds to one or more human proteins selected from the group consisting of human Sortilin, a naturally occurring variant of human Sortilin, and a disease variant of human Sortilin.

[0225] In some embodiments, an anti-Sortilin antibody of the present disclosure is antibody fragment, wherein the antibody fragment is an Fab, Fab', Fab -SH, F(ab')2, Fv, or scFv fragment.Antibody frameworks

[0226] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region comprising one or more (e.g., one or more, two or more, three or more, or all four) framework regions selected from VH FR1, VH FR2, VH FR3, and VH FR4 (as shown in Tables 20-23). In some embodiments, the VH FR1 comprises a sequence of QVQLQESGPGLVKPSETLSL TCAVSG (SEQ ID NO: 35). In some embodiments, the VH FR2 comprises a sequence of WIRQPPGKGLEWIG (SEQ ID NO: 36). In some embodiments, the VH FR3 comprises the sequence according to Formula VI: X 1 VTISVDTSKNQFSLX 2 LSSVTAADTAVYYC (SEQ ID NO: 39), wherein X 1 is Q or R, and X 2 is E or K. In some embodiments, VH FR3 comprises a sequence selected from the group consisting of SEQ ID NOs: 37-38. In some embodiments, VH FR4 comprises a sequence of WGQGTTVTVSS (SEQ ID NO: 40). In some embodiments, an antibody comprises a heavy chain variable region comprising a VH FR1 comprising the sequence of SEQ ID NO: 35, a VH FR2 comprising the sequence of SEQ ID NO: 36, a VH FR3 according to Formula VI, and a VH FR4 comprising the sequence of SEQ ID NO: 40.

[0227] In some embodiments, an antibody comprises a heavy chain variable region comprising a VH FR1 comprising the sequence of SEQ ID NO: 35, a VH FR2 comprising the sequence of SEQ ID NO: 36, a VH FR3 comprising the sequence selected from SEQ ID NOs: 37-38, and a VH FR4 comprising the sequence of SEQ ID NO: 40.

[0228] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region comprising a VH FR1, a VH FR2, a VH FR3, and VH FR4 of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15. 16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24 (as shown in Tables 20-23 ).

[0229] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable region comprising one or more (e.g., one or more, two or more, three or more, or all four) framework regions selected from VL FR1, VL FR2, VL FR3, and VL FR4 (as shown in Tables 24-27). In some embodiments, the VL FR1 comprises a sequence according to Formula VII: DIVMTQSPLSLPVTPGX 1 X 2 ASISC (SEQ ID NO: 44), wherein X 1 is E or G, and X 2 is P or S. In some embodiments, VL FR1 comprises a sequence selected from the group consisting of SEQ ID NOs: 41-43. In some embodiments, the VL FR2 comprises a sequence according to Formula VIII: WYLQKPGQX 1 PQLLIY (SEQ ID NO: 47), wherein X 1 is S or P. In some embodiments, VL FR2 comprises a sequence selected from the group consisting of SEQ ID NOs: 45-46. In some embodiments, the VL FR3 comprises a sequence according to Formula IX: GVPDRX 1 SGSGSGT DFTLKISRX 2 EAEDVGX 3 YYC (SEQ ID NO: 52), wherein X 1 is F or L, X 2 is A or V, and X 3 is V or A. In some embodiments, VL FR3 comprises a sequence selected from the group consisting of SEQ ID NOs: 48-51. In some embodiments, the VL FR4 comprises a sequence of FGGGTKVEIK (SEQ ID NO: 53). In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable region comprising a VL FR1 comprising the sequence according to Formula VII, a VL FR2 comprising the sequence according to Formula VIII, a VL FR3 comprising the sequence according to Formula IX, and a VL FR4 comprising the sequence of SEQ ID NO: 53.

[0230] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable region comprising a VL FR1 comprising the sequence selected from SEQ ID NOs: 41-43, a VL FR2 comprising the sequence selected from SEQ ID NOs: 45-46, a VL FR3 comprising the sequence selected from SEQ ID NOs: 48-51, and a VL FR4 comprising the sequence of SEQ ID NO: 53.

[0231] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a light chain variable region comprising a VL FR1, a VL FR2, a VL FR3, and VL FR4 of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N331], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24 (as shown in Tables 24-27).

[0232] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region comprising one or more (e.g., one or more, two or more, three or more, or all four) framework regions selected from VH FR1, VH FR2, VH FR3, and VH FR4 (as shown in Tables 20-23), and a light chain variable region comprising one or more (e.g., one or more, two or more, three or more, or all four) framework regions selected from VL FR1, VL FR2, VL FR3, and VL FR4 (as shown in Tables 24-27). In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region comprising a

[0233] VH FR1 comprising the sequence of SEQ ID NO: 35, a VH FR2 comprising the sequence of SEQ ID NO: 36, a VH FR3 according to Formula VI, and a VH FR4 comprising the sequence of SEQ ID NO: 4t1; and a light chain variable region comprising a VL FR1 comprising the sequence according to Formula VII, a VL FR2 comprising the sequence according to Formula VIII, a VL FR3 comprising the sequence according to Formula IX, and a VL FR4 comprising the sequence of SEQ ID NO: 53. In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region comprising a VH FR1 comprising the sequence of SEQ ID NO: 35, a VH FR2 comprising the sequence of SEQ ID NO: 36, a VH FR3 comprising the sequence selected from SEQ ID NOs: 37-38, and a VH FR4 comprising the sequence of SEQ ID NO: 40; a light chain variable region comprising a VL FR1 comprising the sequence selected from SEQ ID NOs: 41-43, a VL FR2 comprising the sequence selected from SEQ ID NOs: 45-46, a VL FR3 comprising the sequence selected from SEQ ID NOs: 48-51, and a VL FR4 comprising the sequence of SEQ ID NO: 53.

[0234] In some embodiments, anti-Sortilin antibodies of the present disclosure comprise a heavy chain variable region comprising a VH FR1, a VH FR2, a VH FR3, and VH FR4 of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N336], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24 (as shown in Tables 20-23), and a light chain variable region comprising a VL FR1, a VL FR2, a VL FR3, and VL FR4 of antibody S-60-10, S-60-11, S-60-12, S-60-13, S-60-14, S-60-15 [N33 (wt)], S-60-15.1 [N33T], S-60-15.2 [N33S], S-60-15.3 [N33G], S-60-15.4 [N33R], S-60-15.5 [N33D], S-60-15.6 [N33H], S-60-15.7 [N33K], S-60-15.8 [N33Q], S-60-15.9 [N33Y], S-60-15.10 [N33E], S-60-15.11 [N33W], S-60-15.12 [N33F], S-60-15.13 [N33I], S-60-15.14 [N33V], S-60-15.15 [N33A], S-60-15.16 [N33M], S-60-15.17 [N33L], S-60-16; S-60-18, S-60-19, or S-60-24 (as shown in Tables 24-27). Anti-Sortilin Antibody Activities

[0235] In certain aspects of any of the anti-Sortilin antibodies, anti-Sortilin antibodies of the present disclosure can inhibit one or more activities of a Sortilin protein, including, but not limited to, decreasing cellular levels of Sortilin (e.g., cell surface levels of Sortilin, intracellular levels of Sortilin, and / or total levels of Sortilin); increasing Progranulin levels (e.g., extracellular levels of Progranulin and / or cellular levels of Progranulin); and inhibiting the interaction (e.g., binding) between Progranulin and Sortilin. As contemplated herein, anti-Sortilin antibodies of the present disclosure may inhibit addititional activities of a Sortilin protein, including but not limited to inhibiting interaction (e.g., binding) with one or more of pro-neurotrophins of the present disclosure (pro-neurotrophin-3, pro-neurotrophin-4 / 5, pro-NGF, pro-BDNF, etc.), neurotrophins of the present disclosure (neurotrophin-3, neurotrophin-4 / 5, NGF, BDNF, etc.), neurotensin, p75, Sortilin propeptide (Sort-pro), amyloid precursor protein (APP), the A beta peptide, lipoprotein lipase (LpL), apolipoprotein AV (APOA5), apolipoprotein E (APOE), and receptor associated protein (RAP), decreasing secretion of PCSK9, deacreasing production of beta amyloid peptide..

[0236] In certain embodiments, the present disclosure provides an anti-Sortilin antibody, wherein (a) the anti-Sortilin antibody increases extracellular levels of Progranulin, decreases cellular levels of Sortilin, inhibits interaction between Sortilin and Progranulin, or any combination thereof; (b) the anti-Sortilin antibody decreases cell surface levels of Sortilin, increases extracellular levels of Progranulin, inhibits interaction between Sortilin and Progranulin, or any combination thereof; (c) the anti-Sortilin antibody decreases cell surface levels of Sortilin, decreases intracellular levels of Sortilin, decreases total levels of Sortilin, or any combination thereof; (d) the anti-Sortilin antibody induces Sortilin degradation, Sortilin cleavage, Sortilin internalization, Sortilin down regulation, or any combination thereof; (e) the anti-Sortilin antibody decreases cellular levels of Sortilin and inhibits the interaction between Sortilin and Progranulin; (f) the anti-Sortilin antibody decreases cellular levels of Sortilin and increases cellular levels of Progranulin; and / or (g) the anti-Sortilin antibody increases the effective concentration of Progranulin.

[0237] In certain embodiments, the present disclosure provides an anti-Sortilin antibody, wherein the anti-Sortilin antibody decreases cell surface levels of Sortilin, increases extracellular levels of Progranulin, inhibits interaction between Sortilin and Progranulin, or any combination thereof.

[0238] In some embodiments, an anti-Sortilin antibody of the present disclosure (a) reduces cell surface levels of Sortilin with a half maximal effective concentration (EC 50 ) that is less than 150 pM, as measured by flow cytometry; (b) reduces cell surface levels of Sortilin by more than about 50% at 1.25 nM IgG, by more than about 80% at 0.63 nM IgG, or by more than about 69% at 150 nM IgG relative to control, as measured by flow cytometry; increases Progranulin secretion by more than about 1.13 fold over control at 0.63 nM IgG, or by more than about 1.22 fold over control at 50 nM IgG, as measured by standard ELISA; blocks binding of Progranulin to Sortilin with a half maximal effective concentration (EC 50 ) that is less than .325 nM, as measured by flow cytometry; (e) blocks binding of Progranulin to Sortilin by more than about 88% at 50 nM IgG, or by more than about 27.5% at 150 nM IgG relative to control, as measured by flow cytometry; or (f) any combination thereof (see, e.g., Examples 2-4).

[0239] In some embodiments, an anti-Sortilin antibody of the present disclosure (a) reduces cell surface levels of Sortilin with a half maximal effective concentration (EC 50 ) that is less than 681 pM, as measured by flow cytometry; (b) reduces cell surface levels of Sortilin by more than about 40% at 1.25 nM IgG, by more than about 29% at 0.6 nM IgG, or by more than about 62% at 150 nM IgG relative to control, as measured by flow cytometry; (c) increases Progranulin secretion by more than about 1.11 fold over control at 0.63 nM IgG, or by more than about 1.75 fold over control at 50 nM IgG, as measured by standard ELISA; (d) blocks binding of Progranulin to Sortilin with a half maximal effective concentration (EC 50 ) that is less than 0.751 nM, as measured by flow cytometry; (e) blocks binding of Progranulin to Sortilin by more than about 90% at 50 nM IgG, or by more than about 95% at 150 nM IgG relative to control, as measured by flow cytometry; or (f) any combination thereof (see, e.g., Examples 2-4). Decreasing Sortilin levels

[0240] In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a Sortilin protein of the present disclosure expressed on the surface of a cell and modulate (e.g., induce or inhibit) one or more Sortilin activities of the present disclosure after binding to the surface-expressed Sortilin protein,

[0241] In some embodiments, anti-Sortilin antibodies of the present disclosure decrease cellular levels of Sortilin in vitro. In some embodiments, anti-Sortilin antibodies of the present disclosure may decrease cellular levels of Sortilin in vivo (e.g., in the brain, and / or peripheral organs of an individual). In some embodiments, a decrease in cellular levels of Sortilin comprises a decrease in cell surface levels of Sortilin. As used herein, an anti-Sortilin antibody decreases cell surface levels of Sortilin if it induces a decrease at saturating antibody concentrations (e.g., 0.6 nM, 0.63 nM, 1.25 nM, 50 nM or 150 nM) and / or relative to a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60) in cell surface levels of Sortilin as measured by any in vitro cell-based assays or suitable in vivo model described herein or known in the art. In some embodiments, a decrease in cellular levels of Sortilin comprises a decrease in intracellular levels of Sortilin. As contemplated herein, an anti-Sortilin antibody decreases intracellular levels of Sortilin if it induces a decrease at saturating antibody concentrations and / or relative to a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60) in intracellular levels of Sortilin as measured by any in vitro cell-based assays or suitable in vivo model described herein or known in the art. In some embodiments, a decrease in cellular levels of Sortilin comprises a decrease in total levels of Sortilin. As contemplated herein, an anti-Sortilin antibody decreases total levels of Sortilin if it induces a decrease at saturating antibody concentrations and / or relative to a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60) in total levels of Sortilin as measured by any in vitro cell-based assays or suitable in vivo model described herein or known in the art.

[0242] As used herein, levels of Sortilin may refer to expression levels of the gene encoding Sortilin; to expression levels of one or more transcripts encoding Sortilin; to expression levels of Sortilin protein; and / or to the amount of Sortilin protein present within cells and / or on the cell surface. Any methods known in the art for measuring levels of gene expression, transcription, translation, and / or protein abundance or localization may be used to determine the levels of Sortilin.

[0243] Cellular levels of Sortilin may refer to, without limitation, cell surface levels of Sortilin, intracellular levels of Sortilin, and total levels of Sortilin. In some embodiments, a decrease in cellular levels of Sortilin comprises decrease in cell surface levels of Sortilin. In some embodiments, anti-Sortilin antibodies of the present disclosure that decrease cellular levels of Sortilin (e.g., cell surface levels of Sortilin) have one or more of the following characteristics: (1) inhibits or reduces one or more Sortilin activities; (2) the ability to inhibit or reduce binding of a Sortilin to one or more of its ligands; (3) the ability to reduce Sortilin expression in Sortilin-expressing cells; (4) the ability to interact, bind, or recognize a Sortilin protein; (5) the ability to specifically interact with or bind to a Sortilin protein; and (6) the ability to treat, ameliorate, or prevent any aspect of a disease or disorder described or contemplated herein.

[0244] In some embodiments, an isolated anti-Sortilin antibody of the present disclosure induces downregulation of Sortilin, In some embodiments, an isolated anti-Sortilin antibody of the present disclosure induces cleavage of Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure induces internalization of Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure induces shedding of Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure induces degradation of Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure induces desensitization of Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure acts as a ligand mimetic to transiently activate Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure acts as a ligand mimetic and transiently activates Sortilin before inducing a decrease in cellular levels of Sortilin and / or inhibition of interaction (e.g., binding) between Sortilin and one or more Sortilin ligands. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure acts as a ligand mimetic and transiently activates Sortilin before inducing degradation of Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure acts as a ligand mimetic and transiently activates Sortilin before inducing cleavage of Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure acts as a ligand mimetic and transiently activates Sortilin before inducing internalization of Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure acts as a ligand mimetic and transiently activates Sortilin before inducing shedding of Sortilin. In some embodiments, an isolated anti-Sortilin antibody of the present disclosure acts as a ligand mimetic and transiently activates Sortilin before inducing downregulation of Sortilin expression, In some embodiments, an isolated anti-Sortilin antibody of the present disclosure acts as a ligand mimetic and transiently activates Sortilin before inducing desensitization of Sortilin.

[0245] In certain embodiments, anti-Sortilin antibodies of the present disclosure may decrease cellular levels of Sortilin (e.g., cell surface levels of Sortilin, intracellular levels of Sortilin, and / or total levels of Sortilin) by inducing Sortilin degradation. Accordingly, in some embodiments, anti-Sortilin antibodies of the present disclosure induce Sortilin degradation.

[0246] Anti-Sortilin antibodies of the present disclosure may decrease cellular levels (e.g., cell surface levels) of Sortilin with a half-maximal effective concentration (EC 50 ) (e.g., when measured in vitro) in the picomolar range. In certain embodiments, the EC 50 of the antibody is less than about 680.9 pM. In certain embodiments, the EC 50 of the antibody is about 72.58 pM to about 680.9 nM. In certain embodiments, the EC 50 of the antibody is about 103.6 pM to about 680.9 nM. In certain embodiments, the EC 50 of the antibody is less than about 600 pM, 500 pM, 400 pM, 300 pM, 200 pM, 100 pM, 50 pM, 40 pM, 30 pM, 20 pM, 10 pM, 1pM, or 0.5 pM.

[0247] In some embodiments, the EC 50 of the antibody is less than about or equal to about 675 pM, 650 pM, 625 pM, 600 pM, 575 pM, 550 pM, 525 pM, 500 pM, 475 pM, 450 pM, 425 pM, 400 pM, 375 pM, 350pM, 325 pM, 300 pM, 275 pM, 250 pM, 225 pM, 200 pM, 175 pM, 150 pM, 125 pM, 100 pM, 90 pM, 80 pM, 70 pM, 60 pM, 50 pM, 40 pM, 30 pM, 20 pM, 10 pM, 9 pM, 8 pM, 7 pM, 6 pM, 5 pM, 4 pM, 3 pM, 2 pM, 1 pM, or 0.5 pM.

[0248] In some embodiments, the EC 50 of the antibody is less than about 680.9 pM. In some embodiments, the EC 50 of the antibody is greater than about or equal to about 0.1 pM, 0.5pM, 1 pM, 10 pM, 20 pM, 30 pM, 40 pM, 50 pM, 60 pM, 70 pM, 80 pM, 90 pM, 100 pM, 125 pM, 150 pM, 175 pM, 200 pM, 225 pM, 250 pM, 275 pM, 300 pM, 325 pM, 350 pM, 375 pM, 400 pM, 425 pM, 450 pM, 475 pM, 500 pM, 525 pM, 550 pM, 575 pM, 600 pM, 625 pM, 650 pM, 675 pM. That is, the EC 50 of the antibody can be any of a range having an upper limit of about 675 pM, 650 nM, 650 pM, 625 pM, 600 pM, 575 pM, 550 pM, 525 pM, 500 pM, 475 pM, 450 pM, 425 pM, 400 pM, 375 pM, 350pM, 325 pM, 300 pM, 275 pM, 250 pM, 225 pM, 200 pM, 175 pM, 150 pM, 125 pM, 100 pM, 90 pM, 80 pM, 70 pM, 60 pM, 50 pM, 40 pM, 30 pM, 20 pM, 10 pM, 1 pM, or 0.5 pM, and an independently selected lower limit of about 0.1 pM, 0.5pM, 1 pM, 10 pM, 20 pM, 30 pM, 40 pM, 50 pM, 60 pM, 70 pM, 80 pM, 90 pM, 100 pM, 125 pM, 150 pM, 175 pM, 200 pM, 225 pM, 250 pM, 275 pM, 300 pM, 325 pM, 350 pM, 375 pM, 400 pM, 425 pM, 450 pM, 475 pM, 500 pM, 525 pM, 550 pM, 575 pM, 600 pM, 625 pM, 650 pM, or 675 pM, wherein the lower limit is less than the upper limit. In some embodiments, the EC 50 of the antibody is any of about 1 pM, 2 pM, 3 pM, 4 pM, 5 pM, 6 pM, 7 pM, 8 pM, 9 pM, 10 pM, 15 pM, 20 pM, 25 pM, 30 pM, 35 pM, 40 pM, 45 pM, 50 pM, 55 pM, 60 pM, 65 pM, 70 pM, 75 pM, 80 pM, 85 pM, 90 pM, 95 pM, 100 pM, 105 pM, 110 pM, 115 pM, 120 pM, 125 pM, 130 pM, 135 pM, 140 pM, 145 pM, 150 pM, 155 pM, 160 pM, 165 pM, 170 pM, 175 pM, 180 pM, 185 pM, 190 pM, 195 pM, or 200 pM.

[0249] In some embodiments, an anti-Sortilin antibody of the present disclosure reduces cell surface levels of Sortilin with a half maximal effective concentration (EC 50 ) that is less than 150 pM, as measured by flow cytometry. In some embodiments, the EC 50 of an anti-Sortilin antibody of the present disclosure is about 103.6 pM. In some embodiments, the EC 50 of an anti-Sortilin antibody of the present disclosure is about 72.58 pM.

[0250] In some embodiments, an anti-Sortilin antibody of the present disclosure reduces cell surface levels of Sortilin by more than about 40% at 1.25 nM IgG or by more than about 80% at 0.63 nM IgG, as measured by flow cytometry. In some embodiments, an anti-Sortilin antibody of the present disclosure reduces cell surface levels of Sortilin by about 60.92% at 1.25 nM IgG, as measured by flow cytometry. In some embodiments, an anti-Sortilin antibody of the present disclosure reduces cell surface levels of Sortilin by about 69.3% at 150 nM IgG, as measured by flow cytometry. In some embodiments, an anti-Sortilin antibody of the present disclosure reduces cell surface levels of Sortilin by about 70.3% at 150 nM IgG, as measured by flow cytometry.

[0251] Various methods of measuring antibody EC 50 values are known in the art, including, for example, by flow cytometry (See e.g., Example 2). In some embodiments, the EC 50 is measured in vitro using cells engineered to express human Sortilin. In some embodiments, the EC 50 is measured at a temperature of approximately 4°C. In some embodiments, the EC 50 is measured at a temperature of approximately 25°C. In some embodiments, the EC 50 is measured at a temperature of approximately 35°C. In some embodiments, the EC 50 is measured at a temperature of approximately 37°C. In some embodiments, the EC 50 is determined using a monovalent antibody (e.g., a Fab) or a full-length antibody in a monovalent form. In some embodiments, the EC 50 is determined using antibodies containing constant regions that demonstrate enhanced Fc receptor binding. In some embodiments, the EC 50 is determined using antibodies containing constant regions that demonstrate reduced Fc receptor binding.

[0252] In some embodiments, anti-Sortilin antibodies of the present disclosure have higher potencies in reducing cell surface levels of Sortilin relative to a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure decrease cellular levels (e.g., cell surface levels) of Sortilin with a lower EC 50 (e.g., as measured in vitro) than a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure decrease cellular levels (e.g., cell surface levels) of Sortilin with an EC 50 that is at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least about 99% lower than the EC 50 of a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure decrease cellular levels (e.g., cell surface levels) of Sortilin with an EC 50 that is at least about 1-fold, at least about 1.1-fold, at least about 1.5-fold, at least about 2-fold, at least about 3-fold, at least about 4-fold, at least about 5-fold, at least about 6-fold, at least about 7-fold, at least about 8-fold, at least about 9-fold, at least about 10-fold, at least about 12.5-fold, at least about 15-fold, at least about 17.5-fold, at least about 20-fold, at least about 22.5-fold, at least about 25-fold, at least about 27.5-fold, at least about 30-fold, at least about 50-fold, or at least about 100-fold lower than the EC 50 of a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60).

[0253] In some embodiments, anti-Sortilin antibodies of the present disclosure have an EC 50 that is at least 1.5-fold lower than control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure have an EC 50 that is at least 1.1-fold lower than control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60).

[0254] In some embodiments, an anti-Sortilin antibody of the present disclosure (a) reduces cell surface levels of Sortilin with a half maximal effective concentration (EC 50 ) that is less than 681 pM, as measured by flow cytometry; (b) reduces cell surface levels of Sortilin by more than about 40% at 1.25 nM IgG, by more than about 29% at 0.6 nM IgG, or by more than about 62% at 150 nM IgG relative to control, as measured by flow cytometry; (c) increases Progranulin secretion by more than about 1.11 fold over control at 0.63 nM IgG, or by more than about 1.75 fold over control at 50 nM IgG, as measured by standard ELISA; (d) blocks binding of Progranulin to Sortilin with a half maximal effective concentration (EC 50 ) that is less than 0.751 nM, as measured by flow cytometry; (e) blocks binding of Progranulin to Sortilin by more than about 90% at 50 nM IgG, or by more than about 95% at 150 nM IgG relative to control, as measured by flow cytometry; or (f) any combination thereof (see, e.g., Examples 2-4). Increasing Progranulin levels

[0255] In some embodiments, anti-Sortilin antibodies of the present disclosure increase extracellular levels of Progranulin in vitro. In some embodiments, anti-Sortilin antibodies of the present disclosure may increase cellular levels of Progranulin or in vivo (e.g., in the brain, blood, and / or peripheral organs of an individual). As used herein, an anti-Sortilin antibody increases extracellular levels of Progranulin if it induces an increase at saturating antibody concentrations (e.g., 0.6 nM, 0.63 nM, 1.25 nM, 50 nM or 150 nM) and / or relative to a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60) in extracellular levels of Progranulin as measured by any in vitro cell-based assays or in tissue-based (such as brain tissue-based) assays described herein or known in the art. As contemplated herein, an anti-Sortilin antibody increases cellular levels of Progranulin if it induces an increase at saturating antibody concentrations (e.g., 0.6 nM, 0.63 nM, 1.25 nM, 50 nM or 150 nM) and / or relative to a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60) in cellular levels of Progranulin as measured by any in vitro cell-based assays or in tissue-based (such as brain tissue-based) assays described herein or known in the art.

[0256] As used herein, levels of Progranulin may refer to expression levels of the gene encoding Progranulin; to expression levels of one or more transcripts encoding Progranulin; to expression levels of Progranulin protein; and / or to the amount of Progranulin protein secreted from cells and / or present within cells. Any methods known in the art for measuring levels of gene expression, transcription, translation, protein abundance, protein secretion, and / or protein localization may used to determine the levels of Progranulin.

[0257] As used herein, Progranulin levels may refer to, without limitation, extracellular levels of Progranulin, intracellular levels of Progranulin, and total levels of Progranulin; In some embodiments, an increase in levels of Progranulin comprises an increase in extracellular levels of Progranulin.

[0258] In some embodiments, an anti-Sortilin antibody of the present disclosure increases Progranulin secretion by more than about 1.11 fold over control at 0.63 nM IgG, as measured by standard ELISA. In some embodiments, an anti-Sortilin antibody of the present disclosure increases Progranulin secretion by about 1.42 fold over control at 0.63 nM IgG, as measured by standard ELISA. In some embodiments, an anti-Sortilin antibody of the present disclosure increases Progranulin secretion by more than about 1.75 fold over control at 50 nM IgG, as measured by standard ELISA. In some embodiments, an anti-Sortilin antibody of the present disclosure increases Progranulin secretion by about 1.97 fold over control at 50 nM IgG, as measured by standard ELISA. In some embodiments, an anti-Sortilin antibody of the present disclosure increases Progranulin secretion by about 2.29 fold over control at 50 nM IgG, as measured by standard ELISA.

[0259] Various methods of measuring Progranulin secretion are known in the art, including, for example, by ELISA (See e.g., Examples 2 and 4 ). In some embodiments, the EC 50 is measured in vitro using cells expressing human Sortilin. In some embodiments, Progranulin secretion is determined using a monovalent antibody (e.g., a Fab) or a full-length antibody in a monovalent form. In some embodiments, Progranulin secretion is determined using antibodies containing constant regions that demonstrate enhanced Fc receptor binding. In some embodiments, Progranulin secretion is determined using antibodies containing constant regions that demonstrate reduced Fc receptor binding.

[0260] In some embodiments, anti-Sortilin antibodies of the present disclosure have higher potencies in increasing levels of Progranulin relative to a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure increase levels (e.g., extracellular levels) of Progranulin with a lower EC 50 (e.g., as measured in vitro) than a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure increase levels (e.g., extracellular levels) of Progranulin by at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least about 99% than a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure increase levels (e.g., extracellular levels) of Progranulin by about 1-fold, at least about 1.1-fold, at least about 1.5-fold, at least about 2-fold, at least about 3-fold, at least about 4-fold, at least about 5-fold, at least about 6-fold, at least about 7-fold, at least about 8-fold, at least about 9-fold, at least about 10-fold, at least about 12.5-fold, at least about 15-fold, at least about 17.5-fold, at least about 20-fold, at least about 22.5-fold, at least about 25-fold, at least about 27.5-fold, at least about 30-fold, at least about 50-fold, or at least about 100-fold higher than a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60).

[0261] In some embodiments, anti-Sortilin antibodies of the present disclosure increase Progranulin levels by about 1.1-fold higher than a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure increase Progranulin levels by about 1.3-fold higher than a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60).

[0262] In some embodiments, anti-Sortilin antibodies of the present disclosure increase the effective concentration of Progranulin. The effective concentration of Progranulin refers to the concentration of Progranulin in plasma or cerebrospinal fluid. In some embodiments, an increase in the effective concentration of Progranulin is an increase of greater than 1.5 fold. In some embodiments, the effective concentration of Progranulin is increased for 7-28 days.Decreasing interaction between Sortilin and binding partner

[0263] In certain embodiments, the anti-Sortilin antibodies inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and one or more proteins selected from Progranulin, a pro-neurotrophin, a neurotrophin, pro-neurotrophin-3, neurotrophin-3, pro-neurotrophin-4 / 5, neurotrophin-4 / 5, pro-nerve growth factor (pro-NGF), nerve growth factor (NGF), pro-brain-derived neurotrophic factor (pro-BDNF), brain-derived neurotrophic factor (BDNF), neurotensin, p75, Sortilin propeptide (Sort-pro),amyloid precursor protein (APP), the A beta peptide, lipoprotein lipase (LpL), apolipoprotein AV (APOA5), apolipoprotein E (APOE), PCSK9, and receptor associated protein (RAP), and / or naturally occurring variants. In a specific embodiment, anti-Sortilin antibodies of the present disclosure inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and Progranulin;

[0264] In some embodiments, the anti-Sortilin antibodies may inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and a neurotrophin of the present disclosure, such as a pro-neurotrophin, pro-neurotrophin-3, pro-neurotrophin-4 / 5, pro-NGF, pro-BDNF, neurotrophin-3, neurotrophin-4 / 5, NGF, and BDNF. In other embodiments, the anti-Sortilin antibodies may inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and neurotensin. In other embodiments, the anti-Sortilin antibodies inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and p75. In other embodiments, the anti-Sortilin antibodies may inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and a Sort-pro. In other embodiments, the anti-Sortilin antibodies may inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and APP. In other embodiments, the anti-Sortilin antibodies may inhibit the production of the A beta peptide. In other embodiments, the anti-Sortilin antibodies may inhibit the transport and secretion of PCSK9. In other embodiments, the anti-Sortilin antibodies may inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and LpL. In other embodiments, the anti-Sortilin antibodies may inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and APOA5. In other embodiments, the anti-Sortilin antibodies may inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and APOE. In other embodiments, the anti-Sortilin antibodies may inhibit interaction (e.g., binding) between a Sortilin protein of the present disclosure and RAP.

[0265] In some embodiments, anti-Sortilin antibodies of the present disclosure bind to a Sortilin protein of the present disclosure expressed on the surface of cell and the naked antibodies inhibit interaction (e.g., binding) between the Sortilin protein and one or more Sortilin ligands. In some embodiments, anti-Sortilin antibodies of the present disclosure that bind to a Sortilin protein of the present inhibit interaction (e.g., binding) between the Sortilin protein and one or more Sortilin ligands by reducing the effective levels of Sortilin that is available to interact with these proteins either on the cell surface or inside the cell. In some embodiments, anti-Sortilin antibodies of the present disclosure that bind to a Sortilin protein of the present inhibit interaction (e.g., binding) between the Sortilin protein and one or more Sortilin ligands by inducing degradation of Sortilin.A. Decreasing interaction between Sortilin and Progranulin

[0266] In some embodiments, anti-Sortilin antibodies of the present disclosure increase Progranulin levels and / or decrease cellular levels of Sortilin while blocking (e.g. inhibiting) the interaction (e.g., binding) between Sortilin and Progranulin. Accordingly, in some embodiments, anti-Sortilin antibodies of the present disclosure block the interaction (e.g., binding) between Sortilin and Progranulin; As used herein, an anti-Sortilin antibody blocks the interaction (e.g., binding) between Sortilin and Progranulin if it decreases Progranulin binding to Sortilin relative to a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60) at saturating antibody concentrations (e.g., 0.6 nM, 0.63 nM, 1.25 nM, 50 nM or 150 nM) in any in vitro assay or cell-based culture assay described herein or known in the art.

[0267] Anti-Sortilin antibodies of the present disclosure may decrease Progranulin binding to Sortilin with a half-maximal effective concentration (EC 50 ) (e.g., when measured in vitro) in the picomolar range. In certain embodiments, the EC 50 of the antibody is less than about 2.2 nM. In certain embodiments, the EC 50 of the antibody is less than about 1.22 nM. In certain embodiments, the EC 50 of the antibody is less than about 751 pM. In certain embodiments, the EC 50 of the antibody is about 325 pM to about 751nM. In certain embodiments, the EC 50 of the antibody is about 405 pM to about 751 nM. In certain embodiments, the EC 50 of the antibody is about 588 pM to about 751 nM. In certain embodiments, the EC 50 of the antibody is less than about 2.2 nM, 2.1 nM, 2.0 nM, 1.9 nM, 1.8 nM, 1.7 nM, 1.6 nM, 1.5 nM, 1.4 nM, 1.3 nM, 1.2 nM, 1.1 nM, 1.0 nM, 900 pM, 800 pM, 700 pM, 600 pM, 500 pM, 400 pM, 300 pM, 200 pM, 100 pM, 50 pM, 40 pM, 30 pM, 20 pM, 10 pM, 1pM, or 0.5 pM.

[0268] In some embodiments, the EC 50 of the antibody for decreasing Progranulin binding to Sortilin is less than about or equal to about 2.2 nM, 2.1 nM, 2.0 nM, 1.9 nM, 1.8 nM, 1.7 nM, 1.6 nM, 1.5 nM, 1.4 nM, 1.3 nM, 1.2 nM, 1.1 nM, 1.0 nM, 900 pM, 800 pM, 700 pM, 600 pM, 500 pM, 475 pM, 450 pM, 425 pM, 400 pM, 375 pM, 350pM, 325 pM, 300 pM, 275 pM, 250 pM, 225 pM, 200 pM, 175 pM, 150 pM, 125 pM, 100 pM, 90 pM, 80 pM, 70 pM, 60 pM, 50 pM, 40 pM, 30 pM, 20 pM, 10 pM, 9 pM, 8 pM, 7 pM, 6 pM, 5 pM, 4 pM, 3 pM, 2 pM, 1 pM, or 0.5 pM.

[0269] In some embodiments, the EC 50 of an anti-Sortilin antibody of the present disclosure is about 1.22 nM. In some embodiments, the EC 50 of an anti-Sortilin antibody of the present disclosure is about 588 pM, In some embodiments, the EC 50 of an anti-Sortilin antibody of the present disclosure is about 405 pM. In some embodiments, the EC 50 of an anti-Sortilin antibody of the present disclosure is about 325 pM.

[0270] Various methods of measuring antibody EC 50 values are known in the art, including, for example, by flow cytometry (See e.g., Example 3). In some embodiments, the EC 50 for decreasing Progranulin binding to Sortlin is measured in vitro using cells expressing human Sortilin. In some embodiments, the EC 50 is measured at a temperature of approximately 4°C. In some embodiments, the EC 50 is measured at a temperature of approximately 25°C. In some embodiments, the EC 50 is measured at a temperature of approximately 35°C. In some embodiments, the EC 50 is measured at a temperature of approximately 37°C. In some embodiments, the EC 50 for decreasing Progranulin binding to Sortlin is determined using a monovalent antibody (e.g., a Fab) or a full-length antibody in a monovalent form. In some embodiments, the EC 50 is determined using antibodies containing constant regions that demonstrate enhanced Fc receptor binding. In some embodiments, the EC 50 for decreasing Progranulin binding to Sortlin is determined using antibodies containing constant regions that demonstrate reduced Fc receptor binding.

[0271] In some embodiments, anti-Sortilin antibodies of the present disclosure have higher potencies in reducing Progranulin binding to Sortlin relative to a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure decrease Progranulin binding to Sortlin with a lower EC 50 (e.g., as measured in vitro) than a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure decrease Progranulin binding to Sortlin with an EC 50 that is at least about 5%, at least about 10%, at least about 5%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least about 99% lower than the EC 50 of a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure decrease Progranulin binding to Sortlin with an EC 50 that is at least about -fold, at least about 1.1-fold, at least about 1.5-fold, at least about 2-fold, at least about 3-fold, at least about 4-fold, at least about 5-fold, at least about 6-fold, at least about 7-fold, at least about 8-fold, at least about 9-fold, at least about 10-fold, at least about 12.5-fold, at least about 15-fold, at least about 17.5-fold, at least about 20-fold, at least about 22.5-fold, at least about 25-fold, at least about 27.5-fold, at least about 30-fold, at least about 50-fold, or at least about 100-fold lower than the EC 50 of a control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60).

[0272] In some embodiments, anti-Sortilin antibodies of the present disclosure have an EC 50 that is at least 1.3-fold lower than control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure have an EC 50 that is at least 1 .8-fold lower than control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure have an EC 50 that is at least ,9-fold lower than control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60). In some embodiments, anti-Sortilin antibodies of the present disclosure have an EC 50 that is at least 2.3-fold lower than control antibody (e.g. an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60).

[0273] Any in vitro cell-based assays or suitable in vivo model described herein or known in the art may be used to measure inhibition or reduction of interaction (e.g., binding) between Sortilin and one or more Sortilin ligands. In some embodiments, anti-Sortilin antibodies of the present disclosure inhibit or reduce interaction (e.g., binding) between Sortilin and one or more Sortilin ligands by reducing Sortilin expression (e.g., by reducing cell surface levels of Sortilin). In some embodiments, anti-Sortilin antibodies of the present disclosure inhibit or reduce interaction (e.g., binding) between Sortilin and one or more Sortilin ligands by at least 21%, at least 22%, at least 23%, at least 24%, at least 25%, at least 26%, at least 27%, at least 28%, at least 29%, at least 30%, at least 31%, at least 32%, at least 33%, at least 34%, at least 35%, at least 36%, at least 37%, at least 38%, at least 39%, at least 40%, at least 41%, at least 42%, at least 43%, at least 44%, at least 45%, at least 46%, at least 47%, at least 48%, at least 49%, at least 50%, at least 51%, at least 52%, at least 53%, at least 54%, at least 55%, at least 56%, at least 57%, at least 58%, at least 59%, at least 60%, at least 61%, at least 62%, at least 63%, at least 64%, at least 65%, at least 66%, at least 67%, at least 68%, at least 69%, at least 70%, at least 71%, at least 72%, at least 73%, at least 74%, at least 75%, at least 76%, at least 77%, at least 78%, at least 79%, at least 80%, at least 81%, at least 82%, at least 83%, at least 84%, at least 85%, at least 86%, at least 87%, at least 88%, at least 89%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or more at saturating antibody concentrations utilizing any in vitro assay or cell-based culture assay described herein or known in the art..

[0274] In some embodiments, an anti-Sortilin antibody of the present disclosure blocks Progranulin binding to Sortlin by more than about 90% at 50 nM IgG or by more than about 96% at 150 nM IgG, as measured by flow cytometry. In some embodiments, an anti-Sortilin antibody of the present disclosure blocks Progranulin binding to Sortlin by about 90.74% at 50 nM IgG, as measured by flow cytometry. In some embodiments, an anti-Sortilin antibody of the present disclosure blocks Progranulin binding to Sortlin by about 96.5% at 150 nM IgG, as measured by flow cytometry. In some embodiments, an anti-Sortilin antibody of the present disclosure blocks Progranulin binding to Sortlin by about 96.9% at 150 nM IgG, as measured by flow cytometry.Decreasing expression of pro-inflammatory mediators

[0275] In some embodiments, anti-Sortilin antibodies of the present disclosure may decrease the expression of pro-inflammatory mediators after binding to a Sortilin protein expressed in a cell.

[0276] As used herein, pro-inflammatory mediators are proteins involved either directly or indirectly (e.g., by way of pro-inflammatory signaling pathways) in a mechanism that induces, activates, promotes, or otherwise decreases an inflammatory response. Any method known in the art for identifying and characterizing pro-inflammatory mediators may be used.

[0277] Examples of pro-inflammatory mediators include, without limitation, cytokines, such as type I and II interferons, IL-6, IL12p70, IL12p40, IL-1β, TNF-α, IL-8, CRP, IL-20 family members, IL-33, LIF, OSM, CNTF, GM-CSF, IL-11, IL-12, IL-17, IL-18, and CRP. Further examples of pro-inflammatory mediators include, without limitation, chemokines, such as CXCL1, CCL2, CCL3, CCL4, and CCL5.

[0278] In some embodiments, the anti-Sortilin antibodies of the present disclosure may decrease functional expression and / or secretion of pro-inflammatory mediators, IL-6, IL12p70, IL12p40, IL-1β, TNF-α, GXCL I, CCL2, CCL3, CCL4, and CCL5. In certain embodiments, decreased expression of the pro-inflammatory mediators occurs in macrophages, dendritic cells, monocytes, osteoclasts, Langerhans cells of skin, Kupffer cells, T cells, and / or microglial cells. Decreased expression may include, without limitation, a decrease in gene expression, a decrease in transcriptional expression, or a decrease in protein expression. Any method known in the art for determining gene, transcript (e.g., mRNA), and / or protein expression may be used. For example, Northern, blot analysis may be used to determine pro-inflammatory mediator gene expression levels, RT-PCR may be used to determine the level of pro-inflammatory mediator transcription, and Western blot analysis may be used to determine pro-inflammatory mediator protein levels.

[0279] As used herein, a pro-inflammatory mediator may have decreased expression if its expression in one or more cells of a subject treated with a Sortilin agent, such as an agonist anti-Sortilin antibody of the present disclosure is more than the expression of the same pro-inflammatory mediator expressed in one or more cells of a corresponding subject that is not treated with the agonist anti-Sortilin antibody. In some embodiments, the anti-Sortilin antibody of the present disclosure may decrease pro-inflammatory mediator expression in one or more cells of a subject by at least 10%, at least 15%, at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, at least 100%, at least 110%, at least 115%, at least 120%, at least 125%, at least 130%, at least 135%, at least 140%, at least 145%, at least 150%, at least 160%, at least 170%, at least 180%, at least 190%, or at least 200% for example, as compared to pro-inflammatory mediator expression in one or more cells of a corresponding subject that is not treated with the anti-Sortilin antibody. In other embodiments, the anti-Sortilin antibody may decrease pro-inflammatory mediator expression in one or more cells of a subject by at least at least 1.5 fold, at least 1.6 fold, at least 1.7 fold, at least 1.8 fold, at least 1.9 fold, at least 2.0 fold, at least 2.1 fold, at least 2.15 fold, at least 2.2 fold, at least 2.25 fold, at least 2.3 fold, at least 2.35 fold, at least 2.4 fold, at least 2.45 fold, at least 2.5 fold, at least 2.55 fold, at least 3.0 fold, at least 3.5 fold, at least 4.0 fold, at least 4.5 fold, at least 5.0 fold, at least 5.5 fold, at least 6.0 fold, at least 6.5 fold, at least 7.0 fold, at least 7.5 fold, at least 8.0 fold, at least 8.5 fold, at least 9.0 fold, at least 9.5 fold, or at least 10 fold, for example, as compared to pro-inflammatory mediator expression in one or more cells of a corresponding subject that is not treated with the anti-Sortilin antibody.

[0280] In some embodiments, an anti-Sortilin antibody according to any of the above embodiments may incorporate any of the features, singly or in combination, as described in Sections 1-7 below:(1) Anti-Sortilin antibody binding affinity

[0281] In some embodiments of any of the antibodies provided herein, the antibody has a dissociation constant (Kd) of < 1 µM, < 100 nM, < 10 nM, < 1 nM, < 0.1 nM, < 0.0 1 nM, or < 0.001 nM (e.g., 10 -8< M or less, e.g., from 10 -8< M to 10 -13< M, e.g. , from 10 -9< M to 10 -13< M).

[0282] Anti-Sortilin antibodies of the present disclosure may have nanomolar or even picomolar affinities for the target antigen (e.g., human Sortilin or mammalian Sortilin). In certain embodiments, the binding affinity of an anti-Sortilin antibody of the present disclosure for target antigen (e.g., human Sortilin or mammalian Sortilin) is measured by the dissociation constant, K D . Dissociation constants may be determined through any analytical technique, including any biochemical or biophysical technique such as fluorescent activated cell sorting (FACS), flow cytometry, enzyme-linked immunosorbent assay (ELISA), surface plasmon resonance (SPR), BioLayer interferometry (see, e.g., Octet System by ForteBio), meso scale discover (see, e.g., MSD-SET), isothermal titration calorimetry (ITC), differential scanning calorimetry (DSC), circular dichroism (CD), stopped-flow analysis, and colorimetric or fluorescent protein melting analyses; or a cell binding assay. In some embodiments, the K D for Sortilin is determined at a temperature of approximately 25°C. In some embodiments, the dissociation constant (K D ) may be measured at 4°C or room temperature utilizing, for example, FACS or BioLayer interferometry assay.

[0283] In some embodiments, the K D for Sortilin is determined at a temperature of approximately 4°C. In some embodiments, the K D is determined using a monovalent antibody (e.g., a Fab) or a full-length antibody in a monovalent form. In some embodiments, the K D is determined using a bivalent antibody and monomeric recombinant Sortilin protein,

[0284] In certain embodiments, the K D of an anti-Sortilin antibody of the present disclosure for human Sortilin, mammalian Sortilin, or both, is measured using FACS as described herein (see, e.g., Examples 1 and 4). In certain embodiments, the K D of an anti-Sortilin antibody of the present disclosure for human Sortilin, mammalian Sortilin, or both, is measured using BioLayer Interferometry as described herein (see., e.g., Example 4).

[0285] In some embodiments, the anti-Sortilin antibody has a dissociation constant (K D ) for human Sortilin that is up to 2.5-fold lower than an anti-Sortilin antibody comprising a heavy chain variable region comprising the sequence of SEQ ID NO: 56 and a light chain variable region comprising the sequence of SEQ ID NO: 79, wherein the K D is determined by FACS (see, e.g., Example 1). In some embodiments, the anti-Sortilin antibody has a dissociation constant (K D ) for human Sortilin that ranges from about 1.10E-8 M to about 4.68E-10 M wherein the K D is determined by FACS (see, e.g.. Example 1), or about 270 to about 2910 pM wherein the K D is determined by Bio-layer interferometry (see, e.g.,Example 4).

[0286] In certain embodiments, the K D of an anti-Sortilin antibody of the present disclosure for human Sortilin, mammalian Sortilin, or both, may be less than than 100nM, less than 90 nM, less than 80 nM, less than 70 nM, less than 60 nM, less than 50 nM, less than 40 nM, less than 30 nM, less than 20 nM, less than 0 nM, less than 9 nM, less than 8 nM, less than 7 nM, less than 6 nM, less than 5 nM, less than 4 nM, less than 3 nM, less than 2 nM, less than 1 nM, less than 0.5 nM, less than 0.1 nM, less than 0.09 nM, less than 0.08 nM, less than 0.07 nM, less than 0.06 nM, less than 0.05 nM, less than 0.04 nM, less than 0.03 nM, less than 0.02 nM, less than 0.01 nM, less than 0.009 nM, less than 0.008 nM, less than 0.007 nM, less than 0.006 nM, less than 0.005 nM, less than 0.004 nM, less than 0.003 nM, less than 0.002 nM, less than 0.001 nM,or less than 0.001 nM.

[0287] The dissociation constants (K D ) of anti-Sortilin antibodies for human Sortilin, mammalian Sortilin, or both, may be less than 10 nM, less than 9.5 nM, less than 9 nM, less than 8.5 nM, less than 8 nM, less than 7.5 nM, less than 7 nM, less than 6.9 nM, less than 6.8 nM, less than 6.7 nM, less than 6.6 nM, less than 6.5 nM, less than 6.4 nM, less than 6.3 nM, less than 6.2 nM, less than 6. 1 nM, less than 6 nM, less than 5.5 nM, less than 5 nM, less than 4.5 nM, less than 4 nM, less than 3.5 nM, less than 3 nM, less than 2.5 nM, less than 2 nM, less than 1.5 nM, less than 1 nM, less than 0.95 nM, less than 0.9 nM, less than 0.89 nM, less than 0.88 nM, less than 0.87 nM, less than 0.86 nM, less than 0.85 nM, less than 0.84 nM, less than 0.83 nM, less than 0.82 nM, less than 0.81 nM, less than 0.8 nM, less than 0.75 nM, less than 0.7 nM, less than 0.65 nM, less than 0.64 nM, less than 0.63 nM, less than 0.62 nM, less than 0.61 nM, less than 0.6 nM, less than 0.55 nM, less than 0.5 nM, less than 0.45 nM, less than 0.4 nM, less than 0.35 nM, less than 0.3 nM., less than 0.29 nM, less than 0.28 nM, less than 0.27 nM, less than 0.26 nM, less than 0.25 nM, less than 0.24 nM, less than 0.23 nM, less than 0.22 nM, less than 0.21 nM, less than 0.2 nM, less than 0.15 nM, less than 0.1 nM, less that 0.09 nM, less than 0.08 nM, less than 0.07 nM, less than 0.06 nM, less than 0.05 nM, less than 0.04 nM, less than 0.03 nM, less than 0.02 nM, less than 0.01 nM, less that 0.009 nM, less than 0.008 nM, less than 0.007 nM, less than 0.006 nM, less than 0.005 nM, less than 0.004 nM, less than 0.003 nM, less than 0.002 nM, or less than 0.001 nM.

[0288] In certain embodiments, the dissociation constant (K D ) of the antibody for Sortilin is from about 0.560 nM to about 1.63 nM, for example when the K D is determined by FACS. In certain embodiments, the dissociation constant (K D ) of the antibody for Sortilin is from about 0.270 nM to about 2.910 nM, for example when the K D is determined by BioLayer Interferometry. In some embodiments, the antibody has a dissociation constant (K D ) for human Sortilin, mouse Sortilin, or both, that ranges from about 0.36 nM to about 0.43 nM, or less than 1.02 nM. In some embodiments, the dissociation constant is less than 1.02 nM. In some embodiments, an anti-Sortilin antibody of the present disclosure has a dissociation constant for human Sortilin of .560 nM or less.

[0289] In one specific embodiment, an anti-Sortilin antibody of the present disclosure has a dissociation constant for human Sortilin of about .560 nM. In one specific embodiment, an anti-Sortilin antibody of the present disclosure has a dissociation constant for human Sortilin of about .423 nM. In one specific embodiment, an anti-Sortilin antibody of the present disclosure has a dissociation constant for human Sortilin of about .365 nM. In one specific embodiment, an anti-Sortilin antibody of the present disclosure has a dissociation constant for human Sortilin of about .344 nM. In one specific embodiment, an anti-Sortilin antibody of the present disclosure has a dissociation constant for human Sortilin of about .298 nM. In one specific embodiment, an anti-Sortilin antibody of the present disclosure has a dissociation constant for human Sortilin of about .270 nM. In another specific embodiment, an anti-Sortilin antibody of the present disclosure has a dissociation constant for human Sortilin of about .260 nM.

[0290] In some embodiments, anti-Sortilin antibodies of the present disclosure have a lower dissociation constant (K D ) for Sortilin than a control anti-Sortilin antibody (e.g., a control anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60. In some embodiments, anti-Sortilin antibodies of the present disclosure have a K D for a target (e.g., human Sortilin) that is at least about 5%, at least about 10%, at least about 15%, at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or at least about 99% lower than the K D of a control anti-Sortilin antibody for the target (e.g., a control anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60. In some embodiments, anti-Sortilin antibodies of the present disclosure have a K D for a target (e.g., human Sortilin) that is at least about 1-fold, at least about 1.1-fold, at least about 1.5-fold, at least about 2-fold, at least about 3-fold, at least about 4-fold, at least about 5-fold, at least about 6-fold, at least about 7-fold, at least about 8-fold, at least about 9-fold, at least about 10-fold, at least about 12.5-fold, at least about 15-fold, at least about 17.5-fold, at least about 20-fold, at least about 22.5-fold, at least about 25-fold, at least about 27.5-fold, at least about 30-fold, at least about 50-fold, at least about 100-fold, at least about 200-fold, at least about 300-fold, at least about 400-fold, at least about 500-fold, at least about 600-fold, at least about 700-fold, at least about 800-fold, at least about 900-fold, or at least about 000-fold lower than the K D of a control anti-Sortilin antibody for the target (e.g., a control anti-Sortilin antibody comprising a heavy chain variable region and a light chain variable region corresponding to S-60.

[0291] In some embodiments, anti-Sortilin antibodies of the present disclosure have a K D for human Sortilin that is at least 100-fold lower than an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60. In some embodiments, anti-Sortilin antibodies of the present disclosure have a K D for human Sortilin that is at least 50-fold lower than an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60. In some embodiments, anti-Sortilin antibodies of the present disclosure have a K D for human Sortilin that is at least 10-fold lower than an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60. In some embodiments, anti-Sortilin antibodies of the present disclosure have a K D for human Sortilin that is at least 5-fold lower than an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60. In some embodiments, anti-Sortilin antibodies of the present disclosure have a K D for human Sortilin that is at least 2-fold lower than an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60.

[0292] In a specific embodiment, an anti-Sortilin antibody of the present disclosure has a K D for human Sortilin that is about 2.79-fold lower than an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60. In another specific embodiment, an anti-Sortilin antibody of the present disclosure has a K D for human Sortilin that is about 2.05-fold lower than an anti-Sortilin antibody having a heavy chain variable region and a light chain variable region corresponding to S-60.(2) Antibody fragments

[0293] In some embodiments of any of the antibodies provided herein, the antibody antibodies is an antibody fragment. Antibody fragments include, but are not limited to, Fab, Fab', Fab'-SH, F(ab') 2 , Fv, and scFv fragments, and other fragments described below. For a review of certain antibody fragments, see Hudson et al. Nat. Med. 9: 129-134 (2003). For a review of scFv fragments, see, e.g., WO 93 / 16185; and U.S. Patent Nos. 5571894 and 5587458. For discussion of Fab and F(ab') 2 fragments comprising salvage receptor binding epitope residues and having increased in vivo half-life, see U.S. Patent No. 5869046.

[0294] Diabodies are antibody fragments with two antigen-binding sites that may be bivalent or bispecific. See, for example, EP404097; WO 1993 / 01161; Hudson et al. Nat. Med. 9:129-134 (2003). Triabodies and tetrabodies are also described in Hudson et al. Nat. Med. 9:129-134 (2003). Single-domain antibodies are antibody fragments comprising all or a portion of the heavy chain variable domain or all or a portion of the light chain variable domain of an antibody, In certain embodiments, a single-domain antibody is a human single-domain antibody (see, e.g., U.S. Patent No. 6248516).

[0295] Antibody fragments can be made by various techniques, including but not limited to proteolytic digestion of an intact antibody as well as production by recombinant host cells (e.g., E. coli or phage), as described herein.

[0296] In some embodiments, the antibody fragment is used in combination with a second Sortilin antibody and / or with one or more antibodies that specifically bind a disease-causing protein selected from: amyloid beta or fragments thereof, Tau, IAPP, alpha-synuclein, TDP-43, FUS protein, prion protein, PrPSc, huntingtin, calcitonin, superoxide dismutase, ataxin, Lewy body, atrial natriuretic factor, islet amyloid polypeptide, insulin, apolipoprotein AI, serum amyloid A, medin, prolactin, transthyretin, lysozyme, beta 2 microglobulin, gelsolin, keratoepithelin, cystatin, immunoglobulin light chain AL, S-IBM protein, Repeat-associated non-ATG (RAN) translation products, DiPeptide repeat (DPR) peptides, glycine-alanine (GA) repeat peptides, glycine-proline (GP) repeat peptides, glycine-arginine (GR) repeat peptides, proline-alanine (PA) repeat peptides, proline-arginine (PR) repeat peptides, and any combination thereof.(3) Chimeric and Humanized antibodies

[0297] In some embodiments of any of the antibodies provided herein, the antibody is a chimeric antibody. Certain chimeric antibodies are described, e.g., in U.S. Patent No. 4816567. In one example, a chimeric antibody comprises a non-human variable region (e.g., a variable region derived from a mouse, rat, hamster, rabbit, or non-human primate, such as a monkey) and a human constant region. In a further example, a chimeric antibody is a "class switched" antibody in which the class or subclass has been changed from that of the parent antibody. Chimeric antibodies include antigen-binding fragments thereof.

[0298] In some embodiments of any of the antibodies provided herein, the antibody is a humanized antibody. Typically, a non-human antibody is humanized to reduce immunogenicity to humans, while retaining the specificity and affinity of the parental non-human antibody. In certain embodiments, a humanized antibody is substantially non-immunogenic in humans. In certain embodiments, a humanized antibody has substantially the same affinity for a target as an antibody from another species from which the humanized antibody is derived. See, e.g., U.S. Pat. No. 5530101, 5693761; 5693762; and 5585089, In certain embodiments, amino acids of an antibody variable domain that can be modified without diminishing the native affinity of the antigen binding domain while reducing its immunogenicity are identified. See, e.g., U.S. Pat. Nos. 5766886 and 5869619. Generally, a humanized antibody comprises one or more variable domains in which HVRs (or portions thereof) are derived from a non-human antibody, and FRs (or portions thereof) are derived from human antibody sequences. A humanized antibody optionally will also comprise at least a portion of a human constant region. In some embodiments, some FR residues in a humanized antibody are substituted with corresponding residues from a non-human antibody (e.g., the antibody from which the HVR residues are derived), for example, to restore or improve antibody specificity or affinity.

[0299] Humanized antibodies and methods of making them are reviewed, for example, in Almagro et al. Front. Biosci. 13: 161 9-1633 (2008), and are further described, e.g., in US Patent Nos. 5821337, 7527791, 6982321, and 7087409. Human framework regions that may be used for humanization include but are not limited to: framework regions selected using the "best- fit" method (see, e.g., Sims et al. J. Immunol. 151:2296 (1993)); framework regions derived from the consensus sequence of human antibodies of a particular subgroup of light or heavy chain variable regions (see, e.g., Carter et al. Proc. Natl. Acad. Sci. USA 89:4285 (1992); and Presta et al., J. Immunol. 151 :2623 (1993)); human mature (somatically mutated) framework regions or human germline framework regions (see, e.g., Almagro and Fransson Front. Biosci. 13: 1619-1633 (2008)); and framework regions derived from screening FR libraries (see, e.g., Baca et al. J. Biol. Chem. 272: 10678-10684 (1997) and Rosok et al. J. Biol. Chem. 271:22611-22618(1996)).(4) Human Antibodies

[0300] In some embodiments of any of the antibodies provided herein, the antibody is a human antibody. Human antibodies can be produced using various techniques known in the art. Human antibodies are described generally in van Dijk et al. Curr. Opin. Pharmacol. 5:368-74 (2001) and Lonberg Curr. Opin. Immunol. 20:450-459 (2008).

[0301] Human antibodies may be prepared by administering an immunogen to a transgenic animal that has been modified to produce intact human antibodies or intact antibodies with human variable regions in response to antigenic challenge. One can engineer mouse strains deficient in mouse antibody production with large fragments of the human Ig loci in anticipation that such mice would produce human antibodies in the absence of mouse antibodies. Large human Ig fragments can preserve the large variable gene diversity as well as the proper regulation of antibody production and expression. By exploiting the mouse machinery for antibody diversification and selection and the lack of immunological tolerance to human proteins, the reproduced human antibody repertoire in these mouse strains can yield high affinity fully human antibodies against any antigen of interest, including human antigens. Using the hybridoma technology, antigen-specific human MAbs with the desired specificity can be produced and selected. Certain exemplary methods are described in U.S. Pat. No. 5545807, EP 546073, and EP 546073. See also, for example, U.S. Patent Nos. 6075181 and 6150584 describing XENOMOUSE ™< technology; U.S. Patent No. 5770429 describing HUMAB ®< technology; U.S. Patent No. 7041870 describing K-M MOUSE@ technology, and U.S. Patent Application Publication No. US 2007 / 0061900, describing VELOCIMOUSE ®< technology. Human variable regions from intact antibodies generated by such animals may be further modified, e.g., by combining with a different human constant region.

[0302] Human antibodies can also be made by hybridoma-based methods. Human myeloma and mouse-human heteromyeloma cell lines for the production of human monoclonal antibodies have been described. (See, e.g., Kozbor J. Immunol. 133:3001 (1984) and Boemer et al. J. Immunol. 147:86 (1991)). Human antibodies generated via human B-cell hybridoma technology are also described in Li et al. Proc. Natl. Acad. Sci. USA, 1 03:3557-3562 (2006). Additional methods include those described, for example, in U.S. Patent No. 7189826 (describing production of monoclonal human IgM antibodies from hybridoma cell lines). Human hybridoma technology (Trioma technology) is also described in Vollmers et al. Histology and Histopathology 20(3) :927-937 (2005) and Vollmers et al. Methods and Findings in Experimental and Clinical Pharmacology 27(3): 185-91 (2005). Human antibodies may also be generated by isolating Fv clone variable domain sequences selected from human-derived phage display libraries. Such variable domain sequences may then be combined with a desired human constant domain. Techniques for selecting human antibodies from antibody libraries are described below.

[0303] In some embodiments of any of the antibodies provided herein, the antibody is a human antibody isolated by in vitro methods and / or screening combinatorial libraries for antibodies with the desired activity or activities. Suitable examples include but are not limited to phage display (CAT, Morphosys, Dyax, Biosite / Medarex, Xoma, Symphogen, Alexion (formerly Proliferon), Affimed) ribosome display (CAT), yeast-based platforms (Adimab), and the like. In certain phage display methods, repertoires of VH and VL genes are separately cloned by polymerase chain reaction (PCR) and recombined randomly in phage libraries, which can then be screened for antigen-binding phage as described in Winter et al. Ann. Rev. Immunol. 12: 433-455 (1994). For example, a variety of methods are known in the art for generating phage display libraries and screening such libraries for antibodies possessing the desired binding characteristics. See also Sidhu et al. J. Mol. Biol. 338(2): 299-310, 2004; Lee et al. J. Mol. Biol. 340(5): 1073-1093, 2004; Fellouse Proc. Natl. Acad. Sci. USA 101(34): 12467-12472 (2004); and Lee et al. J. Immunol. Methods 284(-2):1 19-132 (2004). Phage typically display antibody fragments, either as single-chain Fv (scFv) fragments or as Fab fragments. Libraries from immunized sources provide high-affinity antibodies to the immunogen without the requirement of constructing hybridomas. Alternatively, the naive repertoire can be cloned (e.g., from human) to provide a single source of antibodies to a wide range of non-self and also self-antigens without any immunization as described by Griffiths et al. EMBO J. 12: 725-734 (1993). Finally, naive libraries can also be made synthetically by cloning unrearranged V-gene segments from stem cells, and using PCR primers comprising random sequence to encode the highly variable HVR3 regions and to accomplish rearrangement in vitro, as described by Hoogenboom et al. J. Mol. Biol., 227: 381-388, 1992. Patent publications describing human antibody phage libraries include, for example: US Patent No. 5750373, and US Patent Publication Nos. 2007 / 0292936 and 2009 / 0002360. Antibodies isolated from human antibody libraries are considered human antibodies or human antibody fragments herein.(5) Constant Regions including Fc regions

[0304] In some embodiments of any of the antibodies provided herein, the antibody comprises an Fc. In some embodiments, the Fc is a human IgG1, IgG2, IgG3, and / or IgG4 isotype. In some embodiments, the antibody is of the IgG class, the IgM class, or the IgA class.

[0305] In certain embodiments of any of the antibodies provided herein, the antibody has an IgG2 isotype. In some embodiments, the antibody contains a human IgG2 constant region. In some embodiments, the human IgG2 constant region includes an Fc region. In some embodiments, the antibody induces the one or more Sortilin activities or independently of binding to an Fc recept...

Claims

1. An antibody that binds to a human Sortilin protein, wherein the antibody comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 56 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 60.

2. An antibody that binds to a human Sortilin protein, wherein the antibody comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 56 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 57.

3. An antibody that binds to a human Sortilin protein, wherein the antibody comprises a heavy chain comprising the amino acid sequence of SEQ ID NO: 137 and a light chain comprising the amino acid sequence of SEQ ID NO: 142.

4. An antibody that binds to a human Sortilin protein, wherein the antibody comprises a heavy chain comprising the amino acid sequence of SEQ ID NO: 138 and a light chain comprising the amino acid sequence of SEQ ID NO: 142.

5. The antibody of any one of claims 1 to 4, wherein the human Sortilin protein comprises the amino acid sequence of SEQ ID NO: 81.

6. The antibody of claim 1 or claim 2, wherein the antibody is of the IgG class, the IgM class, or the IgA class.

7. The antibody of claim 6, wherein the antibody is of the IgG class and has an IgG1, IgG2, IgG3, or IgG4 isotype.

8. The antibody of claim 7, wherein: (a) the antibody is an IgG1 or IgG2 isotype and the Fc region comprises an amino acid substitution at position P33 1S, wherein the numbering of the residue position is according to EU numbering; (b) the antibody is an IgG1 isotype and the Fc region comprises amino acid substitutions at positions L234A, L235A, and P331S, wherein the numbering of the residue position is according to EU numbering; (c) the antibody is an IgG1, IgG2, or IgG4 isotype and the Fc region comprises an amino acid substitution at position N297A, wherein the numbering of the residue position is according to EU numbering; or (d) the Fc region comprises an amino acid substitution at positions S267E and L328F, wherein the numbering of the residue position is according to EU numbering.

9. The antibody of claim 8, wherein the antibody is an IgG1 isotype and the Fc region comprises amino acid substitutions at positions L234A, L235A, and P331S, wherein the numbering of the residue position is according to EU numbering.

10. The antibody of any one of claims 1-9, wherein the antibody is a human antibody, a bispecific antibody, a monoclonal antibody, a multivalent antibody, or a conjugated antibody.

11. The antibody of claim 10, wherein the antibody is a bispecific antibody recognizing a Sortilin protein and a second antigen.

12. The antibody of claim 11, wherein the second antigen is an antigen facilitating transport across the blood-brain-barrier.

13. The antibody of claim 12, wherein the second antigen is selected from the group consisting of transferrin receptor (TR), insulin receptor (HIR), insulin-like growth factor receptor (IGFR), low-density lipoprotein receptor related proteins 1 and 2 (LPR-1 and 2), diphtheria toxin receptor, CRM197, a llama single domain antibody, TMEM 30(A), a protein transduction domain, TAT, Syn-B, penetratin, a poly-arginine peptide, an angiopep peptide, basigin, Glutl, CD98hc, and ANG1005.

14. The antibody of claim 1 or 2, wherein the antibody is an antibody fragment that binds to a human Sortilin protein.

15. The antibody of claim 14, wherein the antibody fragment is an Fab, Fab', Fab'-SH, F(ab')2, Fv, or scFv fragment.

16. An isolated nucleic acid comprising a nucleic acid sequence encoding the antibody of any one of claims 1-15.

17. A vector comprising the nucleic acid of claim 16.

18. An isolated host cell comprising the vector of claim 17.

19. A method of producing an antibody that binds to Sortilin, comprising culturing the host cell of claim 18 so that the antibody is produced.

20. The method of claim 19, further comprising recovering the antibody produced by the host cell.

21. A pharmaceutical composition comprising the antibody of any one of claims 1-15 and a pharmaceutically acceptable carrier.

22. An antibody according to any one of claims 1-15 for use as a medicament.

23. The antibody according to any one of claims 1-15, for use in a method of preventing, reducing risk of or treating a disease, disorder, or injury selected from the group consisting of frontotemporal dementia, Alzheimer's disease, vascular dementia, seizures, retinal dystrophy, amyotrophic lateral sclerosis, traumatic brain injury, a spinal cord injury, dementia, stroke, Parkinson's disease, retinal degeneration, multiple sclerosis, septic shock, arthritis, osteoarthritis and neuropathic pain.

24. The antibody according to any one of claims 1-15, for use in a method of preventing, reducing risk of or treating a disease, disorder, or injury selected from the group consisting of frontotemporal dementia, Alzheimer's disease, vascular dementia, seizures, retinal dystrophy, amyotrophic lateral sclerosis, traumatic brain injury, a spinal cord injury, dementia, stroke, Parkinson's disease, retinal degeneration, multiple sclerosis, septic shock, arthritis and osteoarthritis.

25. The antibody for use of claim 24, wherein the disease, disorder, or injury is selected from the group consisting of frontotemporal dementia, Alzheimer's disease, amyotrophic lateral sclerosis, and Parkinson's disease.

26. The antibody for use of claim 25, wherein the disease, disorder or injury is frontotemporal dementia.

27. The antibody according to any one of claims 1-15, for use in a method of preventing, reducing risk of or treating an inflammatory disorder.

28. An antibody according to any one of claims 1-15 for use in a method of inhibiting neuroinflammation or axonopathy characterized by short axonal outgrowth and aberrant branching in an individual in need thereof.

29. An antibody according to any one of claims 1-15 for use in a method of promoting wound healing.

30. An antibody according to any one of claims 1-15 for use in a method of preventing, reducing risk of, or treating arthritis in an individual in need thereof.

31. An in vitro method of inhibiting the interaction between Sortilin expressed on a cell and Progranulin, the method comprising exposing a cell expressing Sortilin to the anti-Sortilin antibody of any one of claims 1-15 or the pharmaceutical composition of claim 21.

32. The method of claim 31, wherein the method of inhibiting the interaction between Sortilin expressed on a cell and Progranulin further comprises decreasing the level of Sortilin expressed on the cell surface.

33. The method of claim 31 or 32, wherein the method of inhibiting the interaction between Sortilin expressed on a cell and Progranulin further comprises increasing extracellular levels of Progranulin.

34. The antibody for use of any one of claims 23-26 wherein the method of preventing, reducing risk of or treating the disease, disorder, or injury comprises administering the antibody to an individual having one or more mutations in the gene encoding Progranulin.

35. The antibody for use of claim 34, wherein the individual is heterozygous for one or more loss-of-function mutations in the gene encoding Progranulin.

36. The antibody for use or the method of any one of claims 23-35 wherein the anti-Sortilin antibody comprises two or more anti-Sortilin antibodies.