Distinct effects of gamma interferon on human B-lymphocyte precursor cell lines

The effect of gamma interferon (IFN-gamma) on proliferation and antigenic characteristics of cell lines belonging to the B-cell progenitor compartment was studied. We observed a selective effect of recombinant IFN-gamma but not IFN-alpha on proliferation of the B-precursor cell lines Reh and KM3. On day 4, after addition of 400 mu/ml IFN-gamma the [3H]thymidine uptake in these cells was reduced to 60% and 45% respectively, while no effect of IFN-gamma was evident on the proliferation of the more mature B-cell lines Raji, Ramos, B85, and Daudi. On the other hand, both Reh and Ramos showed induction of major histocompatibility complex (MHC) class I antigen expression in response to 400 mu/ml IFN-gamma. In contrast to 12-O-tetradecanoyl-phorbol-13-acetate (TPA), IFN-gamma did not induce increased MHC class II antigen expression on Reh cells. Taken together, our results indicate that IFN-gamma fulfils distinct functions at different levels in the development of B cells.