Peng B, Alotaibi FT, Sediqi S, et al. - Researchers examined the role of interleukin-1β (IL-1β) in promoting nerve growth factor expression, neurogenesis and deep dyspareunia in endometriosis. In this in vitro study, endometriotic tissue samples were included from 45 women with surgically excised deep uterosacral/rectovaginal endometriosis (n = 12), ovarian endometriomas (n = 14) or superficial peritoneal uterosacral/cul-de-sac endometriosis (n = 19). Outcomes suggest that nerve growth factor (NGF) expression is directly stimulated by IL-1β in endometriosis; further, IL-1β was noted to be associated with local neurogenesis around endometriosis and more severe deep dyspareunia. In primary cultures of endometriosis stroma, endometriosis stromal cells indicated IL-1β induced NGF expression which is partly mediated by c-FOS; the conditioned medium from these endometriosis stromal cells was capable to induce PC12 neuronal differentiation. Notably, the NGF-neutralising antibody and IL-1R1 antagonist (Anakinra) inhibited the effect of this conditioned medium on PC12 neuronal differentiation.