Establishment of human cell lines producing anti-D monoclonal antibodies: identification of Rhesus D antigen

Two cell lines producing monoclonal antibodies have been established from peripheral blood of a negative Rhesus blood donor which has been immunized with positive Rhesus red blood cells. Two monoclonal antibodies Co II 8.8 and Co II 7.12 have been selected. Both are IgG1 antibodies, but recognize different epitopes on the Rhesus D antigen, apparently associated with different subunits of the D antigen. Thus the Co II 8.8, like the positive serum, immunoprecipitates an antigen of a relative molecular weight of 33 kDa, while the Co II 7.12 recognizes an antigen of Mr 42 kDa.