QUANTITATIVE STUDY OF CHIMPANZEE AND GORILLA COUNTERPARTS OF THE HUMAN D-ANTIGEN

The reactivities of three human anti-D monoclonal antibodies (mAbs) wi th human, chimpanzee, and gorilla red blood cells (RBCs) were compared by quantitative radioimmunology and indirect immunofluorescence metho ds. The number of antigenic sites varies widely in gorillas (from 48,0 00-283,000), while in chimpanzees this number is very close to that ob served in human R1R2 RBCs. The affinity of the anti-D antibodies was s lightly lower with ape RBCs than with D-positive human RBCs. In chimpa nzee, the D-like epitopes recognition is enhanced by papain while the gorilla D-like epitopes are destroyed by enzyme treatment.