Human seminal extracellular vesicles enhance endometrial receptivity through leukemia inhibitory factor

Seminal extracellular vesicles (EVs) contain different subgroups that have diverse effects on sperm function. However, the effect of seminal EVs—especially its subgroups, on the endometrial receptivity was largely unknown. Here, we found that the seminal EVs could be divided into high-density EV (EV-H), medium density EV (EV-M), and low-density EV (EV-L), after purification using iodixanol. Then we demonstrated that EV-H could promote the expression and secretion of leukemia inhibitor factor (LIF) in human endometrial cells. In EV-H-treated endometrial cells, we identified 1274 differentially expressed genes (DEGs). DEGs were enriched in cell adhesion and AKT, STAT3 pathways. Therefore, we illustrated that EV-H enhanced the adhesion of human choriocarcinoma JAr cell spheroids to endometrial cells through the LIF-STAT3 pathway. Collectively, our findings indicated that seminal EV-H could regulate endometrial receptivity through the LIF pathway, which would provide novel insights into male fertility.