Cytidine deaminase
View Patent ↗Antibodies that specifically bind to AID (Activation-Induced cytidine Deaminase) proteins, compositions comprising said antibodies, and cells producing said antibodies, are described. The AID proteins are structurally related to APOBEC-1,l an RNA editing enzyme, and have a cytidine deaminase activity similar to APOBEC-1. The AID genes were found by preparing cDNA libraries from mouse B cell clone CH12F3-2 (which undergoes class switch recombination from IgM to IgA at an extremely high rate after activation of the cells by stimulation with cytokines), with and without stimulation with cytokines, and performing subtraction cloning using the libraries.
1. An isolated antibody or antigen binding portion thereof that specifically binds to a polypeptide consisting of SEQ ID NO: 8.
2. An isolated antibody or antigen binding portion thereof that specifically binds to: a mammalian polypeptide encoded by a nucleic acid that hybridizes to the complement of the full length of the coding sequence of SEQ ID NO:7 in 0.9% NaCl at 75° C., wherein the polypeptide has a cytidine deaminase activity.
3. The isolated antibody or antigen binding portion thereof of claim 1 , wherein the antibody is a monoclonal antibody.
4. The isolated antibody or antigen binding portion thereof of claim 2 , wherein the antibody is a monoclonal antibody.
5. The isolated antibody or antigen binding portion thereof of claim 1 , wherein the antibody is a humanized antibody.
6. The isolated antibody or antigen binding portion thereof of claim 2 , wherein the antibody is a humanized antibody.
7. The isolated antibody or antigen binding portion thereof of claim 1 , wherein the antibody inhibits the cytidine deaminase activity of the polypeptide.
8. The isolated antibody or antigen binding portion thereof of claim 2 , wherein the antibody inhibits the cytidine deaminase activity of the polypeptide.
9. A composition comprising the isolated antibody or the portion thereof of claim 1 , and a pharmaceutically acceptable carrier.
10. A composition comprising the isolated antibody or the portion thereof of claim 2 , and a pharmaceutically acceptable carrier.
11. An isolated cell producing the antibody or antigen binding portion thereof of claim 3 .
12. An isolated cell producing the antibody or antigen binding portion thereof of claim 4 .
13. The cell of claim 11 , wherein the cell is a hybridoma obtained by fusing a mammalian myeloma cell with said non-human mammalian B cell that produces said monoclonal antibody.
14. The cell of claim 12 , wherein the cell is a hybridoma obtained by fusing a mammalian mycloma cell with said non-human mammalian B cell that produces said monoclonal antibody.
15. The cell of claim 11 , wherein the cell is a transgenic cell transformed by introducing, into the cell, either or both of a nucleic acid encoding a heavy chain of the monoclonal antibody and a nucleic acid encoding a light chain of the monoclonal antibody.
16. The cell of claim 12 , wherein the cell is a transgenic cell transformed by introducing, into the cell, either or both of a nucleic acid encoding a heavy chain of the monoclonal antibody and a nucleic acid encoding a light chain of the monoclonal antibody.
17. The isolated antibody or antigen binding portion thereof of claim 1 , wherein the antigen binding portion thereof is selected from the group consisting of F(ab′)2, Fab′, Fab, variable fragment of antibody (Fv), single chain Fv (sFv), disulfide stabilized Fv (dsFv), and single domain antibody (dAb).
18. The isolated antibody or antigen binding portion thereof of claim 2 , wherein the antigen binding portion thereof is selected from the group consisting of F(ab′)2, Fab′, Fab, variable fragment of antibody (Fv), single chain Fv (sFv), disulfide stabilized Fv (dsFv), and single domain antibody (dAb).