Structure of Murine Histocompatibility Antigens

The histocompatibility or transplantation antigens are cell-surface glycoproteins that are present on nearly all vertebrate cells but appear in greatest amounts on lymphocytes (Klein 1975). They display an unusually extensive genetic polymorphism, and their function may be intimately connected with the immune response (Ir). Studies of the structure of human (HL-A) and mouse (H-2) major histocompatibility antigens indicate that they are closely associated with β2-microglobulin (Nakamuro et al. 1973; Peterson et al. 1974; Silver and Hood 1974), a protein that has sequence homology with the immunoglobulins (Peterson et al. 1972; Cunningham et al. 1973). This finding is in accord with hypotheses (Burnet 1970; Gaily and Edelman 1972) that the immune system and histocompatibility system may have a common evolutionary origin and that they may share some similar effector functions.