主权项 |
1. An isolated host cell transformed with a vector, wherein the vector encodes a humanized CC49 antibody comprising:
(a) four variable light framework regions and four variable heavy framework regions of a human antibody; a light chain complementarity determining region (L-CDR)1, a L-CDR2, a L-CDR3, a heavy chain complementarity determining region (H-CDR)1, a H-CDR2, and a H-CDR3;
a non-conservative substitution of a first residue at position 91, wherein the first residue is in the L-CDR3 of the antibody; anda substitution of a second residue at position 27b, wherein the second residue is in the L-CDR1 of the antibody;wherein the non-conservative substitution of the first residue at position 91 is a tyrosine to proline substitution, the substitution of the second residue at position 27b is a valine to leucine substitution, the L-CDR1, L-CDR2, L-CDR3, H-CDR1, H-CDR2, and H-CDR3 are a HuCC49V10 antibody L-CDR1, L-CDR2, L-CDR3, H-CDR1, H-CDR2, and H-CDR3, respectively, and the humanized CC49 antibody has a high binding affinity for TAG-72 and is minimally immunogenic, as compared to the HuCC49V10 antibody, deposited as ATCC Accession No. PTA-5416; (b) a light chain complementarity determining region (L-CDR)1, a L-CDR2, and a L-CDR3, a heavy chain complementarity determining region (H-CDR)1, a H-CDR2, and a H-CDR3, all from the HuCC49V10 antibody; wherein the L-CDR3 of the humanized CC49 antibody comprises a non-conservative amino acid substitution at position 91 and has a high binding affinity for TAG-72, as compared to the HuCC49V10 antibody, deposited as ATCC Accession No. PTA-5416; (c) humanized CC49 antibody deposited as ATCC Accession number PTA-4182; or (d) humanized CC49 antibody deposited as ATCC Accession number PTA-4183. |