Monoclonal antibodies directed against the human Leb blood group antigen.

Four monoclonal antibodies produced by hybridomas obtained from a mouse immunized with a human adenocarcinoma cell line SW1116 (Koprowski, H., Steplewski, Z., Mitchell, K., Herlyn, M., Herlyn, D., and Fuhrer, P. (1979) Somatic Cell Genet. 5, 957-972) are directed against the Leb antigen of the human Lewis blood group system. Their specificities were established by binding studies using purified Leb-active ceramide hexasaccharide and by hapten inhibition studies involving oligosaccharides obtained from human milk.