Innate Immunity in the Vagina (Part<scp>I</scp>): Estradiol Inhibits<scp>HBD</scp>2 and Elafin Secretion by Human Vaginal Epithelial Cells

Abstract

Problem Vaginal epithelial cells ( VEC ) are the first line of defense against incoming pathogens in the female reproductive tract. Their ability to produce the anti‐ HIV molecules elafin and HBD 2 under hormonal stimulation is unknown. Method of study Vaginal epithelial cells were recovered using a menstrual cup and cultured overnight prior to treatment with estradiol ( E 2 ), progesterone ( P 4 ) or a panel of selective estrogen response modulators ( SERM s). Conditioned media were recovered and analyzed for protein concentration and anti‐ HIV activity. Results E 2 significantly decreased the secretion of HBD 2 and elafin by VEC over 48 hrs, while P 4 and the SERM s (tamoxifen, PHTTP , ICI or Y 134) had no effect. VEC conditioned media from E 2 ‐treated cells had no anti‐ HIV activity, while that from E 2 / P 4 ‐treated cells significantly inhibited HIV ‐ BaL infection. Conclusion The menstrual cup allows for effective recovery of primary VEC . Their production of HBD 2 and elafin is sensitive to E 2 , suggesting that innate immune protection varies in the vagina across the menstrual cycle.