A series of fusions using mouse myeloma cells and spleen cells from mice immunized with blood group substances or human red cells was performed with the aim of obtaining ABO antibodies suitable for routine blood grouping. Seven strongly agglutinating antibodies against antigens in the ABO system were obtained from 18 fusions. These antibodies were tested extensively in manual and automated routines, and six of them were found to be as good as or better than commercial polyclonal test sera of human origin.

A haemagglutinating monoclonal anti-Le^bL antibody has been obtained from a mouse-mouse hybridoma after immunization with the Leb-active oligosaccharide lacto- N-difucohexaose I, coupled to edestin. Of 13 other antibodies obtained, one was able to agglutinate enzyme-treated erythrocytes of all ABO groups and three more were considered to be anti-Le^bH haemagglutinins. The remaining nine antibodies did not agglutinate red cells. The specificity of the stronger of the anti-Le^bL haemagglutinins was examined by studying its binding to a number of glycoconjugates and oligosaccharides.