Xenoantisera to allotypic specificities of HLA-A and B antigens. Serological characterization.

By using the lysostrip and the blocking of cytotoxicity by Fab2 fragments, HLA-A and B antibodies were detected in sera from rabbits and goats immunized with human high-density lipoprotein (HDL)-associated HLA antigens isolated from sera and from cultured lymphoid cells. After appropriate absorptions, the xenoantisera became specific for HLA-A and B alloantigens, reacted with the same structures as alloantisera, and displayed the same patterns of cross-reactions as alloantisera; however, several xenoantisera contained antibodies cross-reactive with antigens coded by the A and B loci. Our data indicate that HDL-associated HLA antigens isolated from lymphoid cells and from serum efficiently elicit xenoantibodies to allotypic specificities of the human histocompatibility system.