INDUCTION OF FC-RECEPTORS ON MURINE MACROPHAGES AND LEUKEMIC-CELLS BYINTERLEUKIN-1-BETA

Recombinant human interleukin-1beta (rhIL-1beta) is shown to be a stro ng inducer of Fc receptors (FcR) on murine macrophages and not on gran ulocytes. Data is provided indicating that rhIL-1beta does induce spec ific but not nonspecific phagocytosis. Macrophages are shown to autoin duce their FcR expression as a function of time in culture. This induc tion is increased by the use of exogenous rhIL-1beta and inhibited by anti-rhIL-1beta antibody, pointing to an autocrine regulation of FcR e xpression on macrophages. On the other hand the myelomonocytic cell li ne WEHI3BD- and the macrophage like cell line WR19M.1 are also shown t o be inducible for the expression of FcR by this molecule. Data is als o provided showing that recombinant murine Interferon gamma (rmIFNgamm a) induces FcR on both macrophages and granulocytes. Whereas polyclona l antibodies inhibit FcR induction by IL-1 on macrophages, it does not inhibit FcR induction by IFNgamma on these cells. This points to a di fferent mechanism of induction of FcR by EFN and IL-1. Finally, the po ssible application of rhIL-1beta in vivo to help the organism right in fections is discussed.