Heterogeneity of H-2D Region Associated Genes and Gene Products

Abstract

Publisher Summary It is clear that the once accepted dogma that there is only one gene product for each H-2K or H-2D region is incorrect, at least for certain haplotypes. In the case of the H-2D region of the d haplotype designated Dd, there is now a preponderence of data demonstrating at least two gene products, Dd and Ld, determined by two separate genes H-2Dd and H-2Ld, respectively. The cell surface expression of Ld antigens appears 2 to 3 times lower than that of Kd and Dd antigens, and H-2L gene products have been proposed to have unique antigenic properties rendering them less polymorphic than H-2K and H-2D gene products. New technical advances promise to provide the tools to address a few important questions. The availability of monoclonal antibodies to H-2K and H-2D antigens has provided a technical stimulus for the study of class I antigens. Monoclonal antibodies have facilitated the serologic and molecular resolution of H-2 antigens and have circumvented several of the caveats encountered using complex allo-antisera. Recombinant DNA technology not only provides precise information on the genetic organization of H-2 genes, but when taken in the context of serologic, structural, and chemical findings, they should also yield invaluable information regarding the genetic evolution of H-2 molecules.