Characterization of ovarian surface epithelial cells from the hen: a unique model for ovarian cancer

To further develop the hen as a model of ovarian adenocarcinoma, we have studied normal and neoplastic ovaries as well as cultured cells from the ovarian surface epithelium (OSE). We characterized the OSE layer of the hen for specific histologic markers and evaluated these markers on tumor tissue. We also isolated and characterized the epithelial cells that are the likely source of the ovarian tumors of the hen. The surface epithelium of normal ovaries demonstrated positive staining for cytokeratin, proliferating cell nuclear antigen (PCNA), progesterone receptor (PR), and negative staining for vimentin. Ovarian tumors demonstrated positive cytokeratin, PCNA, PR, and weak vimentin staining in the gland-like areas. Epithelial cell cultures were obtained by an explant method utilizing small and large yellow follicles. These cells were positive for cytokeratin and negative for vimentin on Days 1 and 3. By Day 10, cytokeratin protein expression was less for some cells, and vimentin expression was weakly present in some cells. Expression of PCNA was observed at Days 1 and 3, but was rarely seen in cells cultured for 10 days. Expression of PR was observed on Day 10 after 24-hr estrogen treatment. Epithelial cells grew slowly in culture, and were susceptible to trypsin or other dissociation treatments.