Rabbit Anti-Human β2 Microglobulin Antibodies: A T-Cell Mitogen

Rabbit anti-beta 2 microglobulin antibodies have been described as a potent mitogen for human B lymphocytes. However, when fractionated after activation, only the T-cell enriched population is actively dividing. The induction of proliferation in purified T cells requires the presence of non-T cells. Daudi cells (which do not express beta 2 microglobulin on their cell surface) were shown to produce 'macrophage replacing factors' which supported anti-beta 2-induced T cell division. Non-T cells could be effectively replaced by addition of interleukin 2 containing cell supernatants, 12-O-tetradecanoyl-phorbol-13-acetate (TPA), or teleocidin B. Thus, anti-beta 2 appears to selectively activate T cells. In contrast to other T cell mitogens, anti-beta 2 microglobulin antibodies did not induce secondary immunoglobulin production in B cells from peripheral blood or spleen.