Humanization of mouse anti-human IL-2 receptor antibody B-B10.

Mouse monoclonal anti-human IL-2 receptor antibody (B-B10) inhibits IL-2-dependent human T-cell proliferation. It has been used in clinical trials in the transplantation field and promising results are being accumulated. Mouse B-B10 antibody was humanized by grafting all CDRs and some framework amino acid residues onto human antibodies, KAS for V H and PAY for V x . Nine humanized B-B10s with differently grafted framework residues were constructed and assessed for their biological activities. One of these humanized B-B10, M5, showed nearly the same activity as the mouse B-B10. The 49th residue of V x was demonstrated to play a crucial role in the antigen - antibody interaction by 3-D structure analysis with a computer modeling system