Regulatory T Cells are Baby′s Best Friends

Regulatory T cells ( T reg) are one of the most and best studied immune cell population during human and murine pregnancy, and there is a general consent about their expansion during pregnancy. However, the identification of new and more reliable T reg markers during the last years resulted in some controversies about the kinetics of various T reg subsets at different pregnancy stages. No doubt exists regarding the importance of T reg for a normal pregnancy as pregnancy complications like spontaneous abortion and preeclampsia could be associated with a reduced T reg number and activity. In future, more attention should be paid to bring established data from the bench to the bedside to force the development of adequate therapies for treatment of pregnancy complications. In this article, we summarize previous and recent data on several aspects of T reg biology during human and murine pregnancy.