β₂ Microglobulin: a reevaluation

Rabbit antiserum to human β₂ microglobulin was used to inhibit the proliferative response of lymphocytes in a variety of in vitro assays and to block the effector phase of the cell mediated lympholysis reaction. The antiserum was able to inhibit both of these reactions; it is not clear whether the cytotoxic reaction which was studied in a xenogeneic human rabbit system is based on phytohemagglutinin dependent cytotoxicity or on specific recognition of target cells by receptors on the effector cells, or most likely on a combination of both cytotoxic mechanisms. Whereas the possibility that β₂ microglobulin may be associated with receptors on the thymus derived lymphocyte surface is considered, it is also pointed out that the effect of the antiserum may be based on other mechanisms of perturbing the membrane so as to inhibit these responses.