Evaluation of Rh monoclonal antibodies for flow cytometry tests

As participants of the “III International Workshop on Monoclonal Antibodies against Human Red Blood Cells and Related Antigens”, we tested 43 RH monoclonal antibodies by the flow cytometry technique. Besides the anti-D antibodies (not included in this paper), we tested the following antibodies: three (3) anti-C; one (1) anti-C^w; six (6) anti-c; eight (8) anti-E; three (3) anti-e; two (2) anti-G; one (1) anti-CcEe (total = 24 antibodies). These antibodies (from different lab sources) were tested against antigen positive cells (homozygous or heterozygous) and antigen negative cells. When available, some of them were tested against “rare” phenotypes like r_yr, r″^Gr, r^Gr, R₂R_z. All the three anti-C tested, showed poor discrimination between positive and negative cells; from the six anti-c tested, only three had good results (Workshop n° 18, 20, 21) with a superior performance of one of them (Workshop n° 18). From the eight anti-E tested, we found two (Workshop n° 139 and 153) with good performance; all the three anti-e were non reactive; the two anti-G failed to react with r′r red cells; the anti-C^w reacted better with R₁^wr cells than R₁^wR₁; and the anti-CcEe antibody showed good results with all the phenotypes tested. From the 24 antibodies tested, we found six (25%) antibodies with a good performance.