In vitro immunosuppressive properties of spergualins to murine T cell response.

Deoxyspergualin has strong immunosuppressive activity in animals. However, it shows less in vitro immunosuppressive activity at the therapeutic concentration used for in vivo administration. Recently, we reported that there are some technical problems with in vitro experiments. In this report, the effects of spergualins were examined under in vitro conditions which excluded these problems, and compared with cyclosporine A (CYA). Spergualins have suppressive effects on mixed lymphocyte response (MLR) and cytotoxic T lymphocyte induction. Furthermore, interleukin-2 (IL-2) induced proliferation of concanavalin A blasts and CTLL-2 were inhibited at low concentration. However, spergualins have little effect in the early stage of MLR or the mitogen response. These results suggest that spergualins act on the proliferation and differentiation of T cells which respond to growth factors, such as IL-2.