Anti-CD20 antibody and uses thereof
Provided herein are anti-CD20 antibodies and uses thereof for treatment and diagnosis. Also provided are CD20 antigens for the production of anti-CD20 antibodies and methods of generating anti-CD20 antibodies using the CD20 antigens.
1. An isolated antibody or an antigen binding portion thereof that specifically binds to a canine CD20 cyclic peptide having the sequence of SEQ ID NO: 20, wherein the cysteine at position 7 of SEQ ID NO: 20 forms a disulfide bond with the cysteine at position 23 of SEQ ID NO: 20, wherein the antibody or the antigen binding portion comprises a heavy chain variable domain (VH) complementarity determining region (CDR)1 of SEQ ID NO: 40, a VH CDR2 of SEQ ID NO: 42, a VH CDR3 consisting of a threonine (T) residue, and a light chain variable domain (VL) CDR1 of SEQ ID NO: 46, a VL CDR2 of SEQ ID NO: 48, and a VL CDR3 of SEQ ID NO: 50.
2. The isolated antibody or antigen binding portion of claim 1 , comprising a heavy chain variable domain (VH) comprising SEQ ID NO: 4 and/or a light chain variable domain (VL) comprising SEQ ID NO: 6.
3. The isolated antibody or antigen binding portion of claim 1 , wherein the isolated antibody or antigen binding portion is a full length antibody, a Fab fragment, a F(ab′)2 fragment, or a single chain variable fragment (scFV).
4. The isolated antibody or antigen binding portion of claim 1 , wherein the isolated antibody or antigen binding portion comprises SEQ ID NO: 8.
5. A fusion protein comprising the isolated antibody or antigen binding portion of claim 1 , wherein the fusion protein comprises a scFv-Fc fusion protein, immunoconjugate, or bispecific antibody, optionally wherein the fusion protein comprises a second component selected from the group consisting of a cytotoxin, a detectable label, a radioisotope, a therapeutic agent, a liposome, a nanoparticle, a binding protein, or an antibody.
6. A nucleic acid encoding the isolated antibody or antigen binding portion of claim 1 .
7. An expression vector comprising the nucleic acid of claim 6 .
8. A cell comprising the nucleic acid of claim 6 or a vector comprising said nucleic acid.
9. A chimeric antigen receptor comprising (i) an antigen binding portion comprising the isolated antibody or antigen binding portion of claim 1 ; (ii) a transmembrane portion; and (iii) a cytoplasmic signaling portion.
10. A cell expressing a chimeric antigen receptor of claim 9 , wherein the cell is a T cell or natural killer (NK) cell.
11. A pharmaceutical composition comprising the isolated antibody or antigen binding portion of claim 1 ; and a physiologically acceptable diluent, excipient or carrier.
12. A method of treating a condition mediated by B-cells in a subject in need thereof comprising administering to the subject an effective amount of the cell of claim 10 , wherein the condition mediated by B-cells is a B cell lymphoma or an immune mediated disease.
13. The method of claim 12 , wherein the immune mediated disease is an autoimmune disease.
14. A method for detecting a CD20 protein or an extracellular domain of a CD20 protein in a biological sample, comprising contacting a biological sample with the antibody or antigen binding portion of claim 1 .
15. A kit for detecting a CD20 protein or an extracellular domain of a CD20 protein in a biological sample, comprising the antibody or antigen binding portion of claim 1 and at least one reagent for the detection of the antibody or antigen binding portion.
16. The isolated antibody or antigen binding portion of claim 1 , wherein the antibody or antigen binding portion binds to the canine CD20 cyclic peptide at a higher affinity than a linear peptide having the sequence of SEQ ID NO: 21.
17. The cell of claim 8 , wherein the cell is an immune cell, a T-cell or natural killer (NK) cell.
18. The chimeric antigen receptor of claim 9 , wherein the chimeric antigen receptor comprises a CD8 leader sequence, a CD28 costimulatory domain, a CD3-chain, a 4-1BBL costimulatory domain, a PD1-DNR domain, a CD34 domain, or any combination thereof.
19. The autoimmune disease of claim 13 , wherein the autoimmune disease is selected from the group consisting of rheumatoid arthritis, systemic lupus erythematosus (SLE), Sjogren's syndrome, vasculitis, multiple sclerosis, Graves' disease, idiopathic thrombocytopenia, dermatomyositis, immune mediated thrombocytopenia, polymyocytosis, pemphigus, immune mediated hemolytic anemia and bullous pemphigoid.
20. The biological sample of claim 14 , wherein the biological sample is a biopsy, tissue, blood, serum, plasma, or lymphatic fluid sample; or comprises cells that express a CD20 protein or a fragment thereof or is a cell lysate prepared from cells that express a CD20 protein or a fragment thereof; or comprises B cells or a B cell lysate.