Abstract
Type I interferons (IFNs) are pleiotropic cytokines and impact various immune cells, including regulatory T cells (Treg cells). The effect of type-I IFNs on the development and function of Treg cells is quite controversial. Here we induced Treg cells (iTreg cells) from naïve CD4+ T cells in vitro in the presence or absence of IFN-β to elucidate its direct effect on the induction of iTreg cells. We found that IFN-β suppressed the proliferation of iTreg cells but enhanced their expression of anti-apoptotic genes Bcl-2 and Mcl-1 during the development of iTreg cells. We also found that IFN-β promoted suppression of conventional T cell proliferation by iTreg cells. These results suggest that IFN-β promotes the survival and immunomodulatory function of iTreg cells.