Blood group reactivities of SLCL-workshop antibodies

We have tested all 98 workshop antibodies for blood group antigen reactivity. In initial experiments we used a routine agglutination technique with A1LEb and BLea erythrocytes to screen for reactivity with most of the possible antigens. Except for WS78 which reacted with both types of erythrocyte and WS92 which reacted with A1Leb, there was only very weak or no reactivity. We therefore used indirect immunofluorescence and a cell analyser to increase sensitivity and tested a variety of erythrocytes expressing different blood group antigens. WS78 was strongly reactive against all types of erythrocyte tested (96-99% of the cells). WS92 appeared to react with blood group A1. WS27 detected an antigen present on all erythrocytes but expressed weakly (19-21% of the cells).