Policing pregnancy: Tregs help keep the peace

Effector T cells must be kept under control to suppress autoimmunity and immunity to innocuous antigens encountered at mucosal surfaces. In mice, T cells with regulatory functions are potent suppressors of T-cell responses and can protect tissues from T-cell-mediated destruction. The aim of this research focus is to summarize recent reports suggesting that regulatory T cells (Tregs) might be key components that protect mammalian fetuses from potentially lethal maternal adaptive immunity. Hence, defective generation or function of Tregs might explain some cases of human pregnancy failure.