Humanization and molecular modeling of the anti-CD4 monoclonal antibody, OKT4A

Autor: V L Pulito, V A Roberts, J R Adair, A L Rothermel, A M Collins, S S Varga, C Martocello, M Bodmer, L K Jolliffe, R A Zivin
Rok vydání: 1996
Předmět:
Zdroj: The Journal of Immunology. 156:2840-2850
ISSN: 1550-6606
0022-1767
DOI: 10.4049/jimmunol.156.8.2840
Popis: OKT4A, a murine mAb that recognizes an epitope on the CD4 receptor, is a potent immunosuppressive agent in vitro and in a variety of nonhuman primate models of graft rejection and autoimmune disease. Initial human cardiac transplant trials suggest that OKT4A does not cause either cytokine release syndrome or CD4+ cell depletion, but does induce a human anti-mouse Ab (HAMA) response despite strong concurrent immunosuppression. To further investigate the potential of OKT4A as an immunomodulator, it was necessary to decrease its immunogenicity. Therefore, we developed a humanized version of this Ab (gOKT4A-4), which has the same binding affinity and in vitro immunosuppressive properties of OKT4A, but retains only three murine sequence-derived amino acid residues outside of the complementarity-determining regions (CDRs). Detailed computer modeling of both OKT4A and gOKT4A-4 provided a computational rationale for the changes necessary to regain activity after humanization. This has also provided a plausible representation of the Ag binding site. Preliminary clinical results with gOKT4A-4 suggest that we have eliminated the immunogenicity observed in the parent murine Ab.
Databáze: OpenAIRE