Morpho-functional characterization of equine endometrial epithelial cells in vitro - preliminary results

Influences of different culture media and growth surfaces on morpho-functional characteristics of equine endometrial epithelial cells (EEC) in vitro were investigated in order to optimize culture conditions. Therefore, the results were compared to the endometrium in situ. Equine EEC were cultured using different media with varying serum components and additives: foetal bovine serum plus additives (MFBS+A), foetal bovine serum (MFBS), horse serum 1 (MHS1), horse serum 2 (MHS2) and horse serum 3 (MHS3). Uncovered and Matrigel (TM)-covered cell culture inserts, as well as cell culture flasks were used. Cultured cells were examined cytomorphologically (hoemoloun-eosin staining, giemsa staining), cytochemically (alcian blue staining) and immunocytochemically (oestrogen receptor (ER) alpha, progesterone receptor, proliferating cell nuclear antigen, inhibin-alpha, cytokeratin 8, 18, 19, vimentin, a-actin, desmin, transforming growth factor (TGF)-alpha, -beta 1, -beta 2, -beta 3). Further, tissue samples of the uteri from which the cells were isolated were examined histopathologically (hoemalaun-eosin staining), histochemically (alcian blue staining) and immunohistochemically, using the above-mentioned antibodies. Regardless of the used media and the state of the endometrial cycle at point of isolation, two morphologically different cell types and three growth patterns were found. None of these facts led to apparent differences concerning immunolabelling. Whereas growth surfaces, duration of culture and state of endometrial cycle at point of isolation did not cause any obvious influences on the immunolabelling of EEC in vitro concerning the utilized antibodies, the culture media did. Especially cells grown in MFBS+A exhibited characteristics comparable to uterine glandular epithelia in situ concerning cytokeratin 8, 18, 19, TGF-beta 1, -beta 3 and ER alpha.