Studies of human endometrium in organ culture

Endometrial stromal cells regulate epithelial cell growth in vitro: a new co-culture model

The regulation of epithelial cell function and morphogenesis by the paracrine effectors from the mesenchyme or stroma has been well established using in-vivo studies. A more complete understanding of these relationships has been delayed due, in part, to a lack of appropriate co-culture models. In this study, we describe a co-culture model which demonstrates that normal paracrine relationships can be reconstituted in vitro and that human endometrial stromal cells regulate both growth and differentiation of primary human endometrial epithelial cells. Interesting differences in the proliferation of stromal and epithelial cells were noted in response to the basement membrane extract, Matrigel((R)). Exposure of stromal cells to Matrigel((R)) enhanced the paracrine capacity of these cells in vitro. When epithelial cells were co-cultured in contact with stromal cells embedded in Matrigel((R)), epithelial cell growth was inhibited by 65-80% compared to controls. Stromal cells in contact with Matrigel((R)) also regulated epithelial cell differentiation, as shown by induction of glycodelin expression. These co-culture studies show great promise as a method to investigate the cellular interactions between endometrial stromal and epithelial cells and their environment and to understand the molecular basis for the regulation of normal growth and differentiation of cells within complex tissues such as the endometrium.

Benzo[a]pyrene metabolism in organ cultures of human endometrium

Twenty-six specimens of normal human endometrium were obtained for studies of [3H]benzo[alpha]pyrene metabolism in short-term organ culture. The tissues were capable of converting benzo[alpha]pyrene (BP) to oxygenated derivatives which co-chromatographed with dihydrodiols, quinones and monohydroxy derivatives of BP. A sulfate conjugate of a monohydroxy BP was also found among the acetone/ethyl acetate soluble products. When the acetone/ethyl acetate soluble metabolites were analyzed using high-pressure liquid chromatography (HPLC), the proportion of metabolites were found to vary greatly from specimen to specimen. Eight women smoked cigarettes but the BP metabolite profiles from organ cultures of endometrial tissue from these women did not differ from those who did not smoke. The average value for sulfate conjugates of monohydroxy BP was significantly lower in endometrial tissue from three postmenopausal women (ages 49, 57 and 58) than among premenopausal women. Specimens from premenopausal women which had been in organ culture for 2 weeks prior to the addition of [3H] BP produced metabolite profiles similar to those of specimens from postmenopausal women with a greatly reduced proportion of BP-phenol sulfate conjugates. These data suggest that the absence of hormonal stimulus (i.e., advanced age or conditions of organ culture) may affect the metabolism of BP in human endometrial tissue.