[An attempt at in vitro reconstruction of the human endometrium by serum-free collagen gel culture of glandular epithelial cells and stromal cells]

Normal human endometrial epithelial cells were obtained from premenopausal women at the time of necessary hysterectomy. The cells were cultured in, or on, collagen gels in a serum-free medium, and were also co-cultured with endometrial stromal cells in order to reconstruct an in vitro model of the endometrium. They were observed morphologically and effects of estrogen (E) and progesterone (P) on the cultured cells were assessed. The epithelial cells and the stromal cells were separated by collagenase digestion and filtration through stainless steel sieves. The floating collagen gel method was used. The epithelial cells on the gels formed a monolayer sheet of columnar or cuboidal cells, and those in the gels grew three-dimensionally to form round or oval glands. The stromal cells co-cultured with the epithelial cells formed cell masses just under the epithelial cell layer quite similar to those of the endometrium in vivo. The epithelial cells on the gels did not migrate into the gels, nor did the stromal cells in the gels proliferate outside of the epithelial cell layer. The epithelial cells did proliferate, showing mitotic activity, but there was no evidence of their responding to E and/or P. The endometrial stromal cells themselves did not decidualize following the addition of E and/or P to the medium.