Suppressive effect of 17-β-estradiol and progesterone on macrophage proliferation

Collabration between the immunological and hormonal system in females is crucial for basic cellular and molecular processes responsible for successful reproduction. The aim of this study was to evalute the effect of estradiol and proliferation of bone marrow derived macrophages of BALB/c (H-2(d)) mice. Applying an in vitro model, the study demonstrated that macrophage proliferation is significantly inhibited by estradiol and progesterone when these two hormones are used together, and that apoptosis is involved in this process. This suggests that estradiol and progesterone may temporarily reduce the number of immune cells (macrophages) in the reproductively tract during a particular period of the ovarian cycle when protecting the gametes/embryo against the effector arm of the immune system is the most vital.