Role of chemokines in the endometrium and in embryo implantation

Purpose of review Chemokines are well known for their roles in the immune system; convincing evidence has emerged demonstrating a broader role for chemokines in the endometrium, particularly during embryo implantation. This review highlights the evidence on newly defined roles for chemokines in the endometrium during embryo implantation, with particular focus on those chemokines expressed by the endometrium. Recent findings The highly regulated temporal and spatial expression of chemokines in the endometrium leads not only to specific recruitment and activation of appropriate leucocytes but also coordinates the precisely orchestrated invasion of trophoblasts through the decidua and maternal vasculature. Results to date implicate chemokine signalling at the maternal-foetal interface in important processes during implantation and placentation, such as leucocyte recruitment and controlled trophoblast invasion. Unravelling such actions of chemokines in the endometrium has provided new insights into these complex processes. Summary Disturbances of chemokine production, processing, or actions are likely to contribute to dysfunction of implantation and placentation, with implications for early pregnancy loss and disturbed placental and foetal development. More research into altered chemokine function in such conditions may provide leads for new clinical interventions.