PARENT SESSION

(118) CYTOKINES REGULATE MATRIX METALLOPROTEINASES IN HUMAN UTERINE ENDOMETRIAL STROMAL CELLS.

Braundmeier, Andrea¹, Nowak, Romana¹, ¹ University of Illinois, Urbana, IL

ABSTRACT- Endometriosis is the presence of ectopic uterine endometrial tissue in the peritoneal cavity. Peritoneal fluid samples of women with endometriosis show elevated IL-1, TNF- and TGF-₁ levels, indicating that an altered immune system may play an important role in the pathogenesis of endometriosis. The invasion of ectopic endometrium into peritoneal mesothelium requires matrix metalloproteinases (MMPs) for tissue remodeling. Several MMPs are differentially expressed in human uterine endometrium with menstrual endometrium showing the highest level of expression. MMPs are stimulated by cytokines and also the protein extracellular matrix metalloproteinase inducer (EMMPRIN). In order to determine the role of cytokines in ectopic endometrial invasion we investigated whether cytokines could stimulate MMP secretion by endometrial stromal cells and whether this stimulation occurred through EMMPRIN. Human decidual uterine fibroblasts (HUDF) were treated with IL-1, TGF-₁ and TNF- in a dose dependent and time dependent manner (C, .1, 1, 10 ng/ml IL-1 or TGF-₁; C, 2, 10, 50 ng/ml TNF-) for 0, 6, 12, and 24 hours. Cell conditioned medium samples were collected and concentrated at each timepoint for immunoblot analysis. Cellular RNA was collected for real time PCR analysis of MMP-1, 2, 3 and EMMPRIN mRNA levels. Our results showed that IL-1 stimulated MMP-1 and 3 protein secretion and mRNA levels in a time and dose dependent manner (p<0.05). TNF- stimulated MMP-1 and 3 protein secretion in a time dependent manner and stimulated MMP-1, 2 and 3 mRNA levels in a time dependent manner (p<0.05). Neither IL-1 nor TNF- treatment affected MMP-2 protein secretion. TGF-₁ inhibited MMP-1, 2 and 3 mRNA levels but exerted no effect on MMP protein secretion (p<0.05). None of these cytokines affected EMMPRIN protein or mRNA levels. These data show that elevated cytokines may play a role in the establishment of ectopic endometrium in the peritoneal cavity by stimulating MMPs to remodel the mesothelial lining of the peritoneum thus allowing for tissue invasion. The stimulation of MMPs by cytokines is independent of EMMPRIN expression.

KEY WORDS: Cytokines, EMMPRIN, Endometriosis, Endometrium