Mycoplasma-lymphocyte interactions: Ir gene control of mitogenesis and a paradoxical interaction with thy-1 bearing cells.

A novel interaction occurs between mycoplasmas and lymphocytes whereby the mycoplasmas behave as multivalent ligands and, following attachment to the lymphocyte plasma membrane, redistribute to one pole of the cell. This mycoplasma-capping event is accompanied by co-capping of certain specific lymphocyte surface antigens. Mycoplasma capping occurs on both lymphoblastoid cells and resting lymphocytes. There is a high degree of correlation between mycoplasma capping on resting (splenic) lymphocytes and blast transformation of these cells. This appears to be a general phenomenon, and many different mycoplasma species are mitogenic for lymphocytes from a number of animal species, including human. In the mouse, mycoplasma-induced triggering does not appear to be influenced by H-2 differences and the primary lymphocyte triggered is the B cell. In other animal species T cells or B and T cells are stimulated. The importance of these interactions with reference to mycoplasma pathogenesis will be discussed.