ABSTRACT
The major histocompatibility complex (MHC) of mammals has been the focus of most of the studies involving the identification of alio antigenic gene products that block tissue transplantation. The smaller magnitude of the immune response to the individual antigens in this family, in comparison with MHC antigens, has prompted their classification as “minor” histocompatibility antigens. The in vivo immune response to minor H antigens is primarily revealed through T-cell-mediated reactions to allogeneic tissue grafts. Suppressor T cells have been observed to be derived from populations that present multiple minor H antigens to responder populations. The major obstacle encountered in analyzing the mechanisms involved in mediating and regulating the T-cell response to minor H antigens has been their elusive identification. The family of minor histocompatibility antigens in the mouse was discovered as the major histocompatibility complex, H-2, but the genetic and immunologic analyses of minor H antigens have lagged far behind similar analyses of H-2 and its associated alloantigens.
