ANTIGENIC DETERMINANTS OF HUMAN SERUM RETINOL-BINDING PROTEIN AS PROBED WITH MONOCLONAL-ANTIBODIES

Monoclonal antibodies raised against human serum retinol-binding prote in (hRBP) were used as probes for the study of the antigenic determina nts of hRBP and those shared with the same protein from other species. The antibodies could be classified into four distinct groups and reac t with the homologous proteins from the rat as well as the rabbit sera . Three of these antibodies recognize sequential or continuous epitope s while the remaining antibody is directed against a discontinuous or conformational epitope. By chemical cleavage with cyanogen bromide, th e domains recognized by the monoclonal antibodies could be delineated. By solid-phase synthetic approach, the core sequences recognized by t wo of these monoclonal antibodies were identified to amino acid sequen ces 45-51 and 128-131 of the primary amino acid sequence of hRBP.