Secretion of Bioactive Interleukin-1, Interleukin-6, and Colony-Stimulating Factors by Human Ovarian Surface Epithelium1

Abstract

The ovarian surface epithelium (OSE) takes part in the lysis and repair of the ovulatory site. It also forms invaginations and cysts that give rise to the majority of ovarian epithelial carcinomas. In the present study, we investigated the capacity of cultured human OSE to secrete cytokines that may contribute to the regulation of ovarian functions and may influence ovarian carcinogenesis. Bioassays, combined with antibody neutralization experiments, showed that OSE cells in short-term culture secrete bioactive interleukin-1 (IL-1), interleukin-6 (IL-6), macrophage colony-stimulating factor (CSF-1), granulocyte colony-stimulating factor (G-CSF), and limited granulocyte-macrophage colony-stimulating factor (GM-CSF). There was a tendency for these factors to be absent or secreted in reduced amounts in SV40-immortalized OSE lines and in two ovarian carcinoma lines. No IL-2, IL-3, or IL-4 was detected. The results show that normal OSE cells secrete factors that are known to have regulatory effects on follicular growth and differentiation, ovulation, and the distribution of intraovarian cells of the immune system. In addition, the results suggest that the secretion of cytokines by ovarian carcinomas represents the retention of normal precursor cell properties, rather than new characteristics acquired as a result of neoplastic progression.