NLRP3 activated macrophages promote endometrial stromal cells migration in endometriosis.

Endometriosis (EMs) is a common gynecological disease whose pathogenesis remains unclear. Immunological factors have been a key hotspot in recent years. Peritoneal fluid samples from women with EMs show defectively activated macrophages (MΦs) and strong NOD-like receptor family pyrin domain containing 3 (NLRP3) expression. Activated MΦs secrete interleukin 1β, which stimulates migration of endometrial stromal cells (ESCs) and promotes accumulation of extracellular matrix. Levels of interleukin 1β in peritoneal fluid were significantly higher in patients with stage III-IV EMs compared with stage I-II EMs. We also found that the size and weight of endometrial lesions in NLRP3-/- mice were significantly lower than those of wild-type mice, and this phenomenon was reversed by intraperitoneally injecting peritoneal MΦs derived from wild-type mice. Moreover, we observed that the NLRP3 inflammasome was activated in MΦs by crosstalk between MΦs and ESCs. Targeted inhibition of NLRP3 significantly reduced lesion development in vivo and suppressed the migration ability of ESCs in vitro. Collectively, these findings suggest that the occurrence of EMs may be associated with the interaction between MΦs and ESCs.