HUMAN ENDOMETRIAL INTERLEUKIN-6 (IL-6) - IN-VIVO MESSENGER-RIBONUCLEIC-ACID EXPRESSION, IN-VITRO PROTEIN-PRODUCTION, AND STIMULATION THEREOF BY IL-1-BETA

Objective: To investigate human endometrial interleukin-6 (IL-6) expre ssion and effects thereon by IL-1 beta. Design: Prospective. Setting: Academic medical center. Patient(s): Endometrial biopsy specimens from normal volunteers (n = 20) at four specific menstrual stages were use d for in vivo study. Endometrial specimens for in vitro study were obt ained from patients (n = 19) undergoing gynecologic surgery. Intervent ion(s): Time and dose-response treatment of endometria with IL-1 beta in tissue culture. Main Outcome Measure(s): In vivo IL-6 messenger RNA expression by Northern analysis and in vitro endometrial IL-6 protein production by assay of the conditioned media. Result(s): Midsecretory and late secretory phase endometria expressed more IL-6 messenger RNA than late proliferative phase endometria in vivo. Similarly in vitro, in pg/mg endometrium per hour secretory endometria IL-6 protein produ ction, 25.7 +/- 7.1 (mean +/- SEM), exceeded that of proliferative end ometria, 4.7 +/- 1.0. With IL-1 beta treatment, secretory endometria I L-6 protein production exceeded that of proliferative endometria. Inte rleukin-1 beta stimulated endometrial IL-6 protein production in time- and dose-dependent manners. Conclusion(s): Human endometrial IL-6 exp ression varies with the menstrual cycle, occurs more highly in secreto ry endometria, and in vitro is stimulated by interleukin-1 beta. Human endometrial IL-6 may therefore mediate some actions of IL-1 beta invo lving the endometrium and trophoblast.