Anti-HLA-A,B,C monoclonal antibodies with no alloantigenic specificity in humans define polymorphisms in other primate species

Abstract

THE study of evolutionary relationships by immunological comparison of homologous proteins from different species has been limited by the complexity and variability of conventional heteroantisera¹. These problems can be avoided by using selected panels of monoclonal antibodies, specific for single antigenic determinants, which would enable detailed immunochemical descriptions of homologous proteins to be made². The human HLA-A,B,C antigens and their homologues provide a particularly interesting system for this type of analysis³. Although they are extraordinarily polymorphic within species, many features of their structure, including association with β-microglobulin, have been highly conserved during evolution^4–6. A preliminary survey showed that monoclonal antibodies with specificity for the HLA-A,B,C–β₂-microglobulin complex reacted with primate species but not with non-primates⁷. We have therefore concentrated on comparing primate species with a panel of anti-A,B,C monoclonal antibodies. We report here the finding that two different anti-HLA-A,B,C monoclonal antibodies with no demonstrable polymorphic specificity in humans define polymorphisms in owl and spider monkeys, thus demonstrating the potential of these reagents for fine structure antigenic mapping.