Acquisition of receptive endometrium: partaking of inflammation

Yulia Gnainsky

Our study aims at exploring the inflammatory components of successful implantation. For this purpose we analyze uterine endometrial samples recovered from patients with fertility problems treated by in vitro fertilization (IVF). Some of these patients underwent endometrial biopsy during the menstrual cycle preceding IVF. Our results demonstrate that endometrial biopsy triggers an inflammatory response characterized by the influx of macrophages and dendritic cells (DCs) (HLA-DR+CD11c+), as well as by an increase in proinflammatory cytokines.

We also show that these cells may have a direct favorable effect on epithelial differentiation. Most importantly, we found that the abundance of macrophages/DCs and the expression of biopsy-induced cytokines positively correlate with pregnancy outcome.

Taken together, these findings imply that the injury-induced inflammatory response facilitates the transition of a non-receptive uterus into a receptive uterus, a reaction that does not take place in infertile patients in absence of endometrial treatment