“Chemerin/chemerin receptor axis plays a role in the accumulation of NK cells in the decidua during pregnancy”

During early pregnancy, human uterine mucosa decidualization is accompanied by a drastic enrichment of CD56highCD16negative NK (dNK) cells even if their origin is still unclear. We and others have reported that several chemokines are able to support peripheral blood NK (pbNK) cell migration through decidual endothelial cells (DEC) and stromal cells (ST) suggesting that this process can contribute to the accumulation of NK cells in the decidual compartment during the first trimester of gestation (1). Here we analyzed whether chemerin, a recently identified chemoattractant for NK cells, is expressed in the uterine compartment and whether it can contribute to pbNK cell recruitment into the uterus. Chemerin belongs to the cathelicidin/cystatin family of proteins, and it is synthesized and secreted as an inactive precursor, prochemerin, present in the plasma at nanomolar concentration. Notably, we found that ST cells isolated from pregnant women express higher levels of chemerin mRNA and ar