Deficient antiendometrium lymphocyte-mediated cytotoxicity in patients with endometriosis

Abstract

To study the possible role of the immune system in the pathogenesis of endometriosis. A cytotoxicity assay by 51Cr release was performed to determine the lymphocyte cytotoxic response toward endometrial targets and an erytroleukemic cell line (K562). The assays were performed in an academic research environment. Twenty-five control women and 25 patients with endometriosis were selected on the basis of laparoscopic examination. The lymphocyte cytotoxic activity was evaluated separately on endometrial stromal and epithelial cells after 4 hours' incubation. The study was designed to determine, in controls and endometriosis patients, the lymphocyte-mediated cytotoxicity toward stromal and epithelial cells of endometrium. The lymphocyte response in the presence of stromal cell antigens was significantly lower (P less than 0.02) in disease-affected women when compared with that obtained in controls (2.89 +/- 0.87 and 7.64 +/- 1.66, respectively). In contrast, when the same assay was performed on K562 cells, no difference was observed between endometriosis patients and controls. These data suggest that an altered immune recognition might be one of the pathogenic mechanisms of endometriosis. Moreover, they indicate that this is not a general phenomenon but is specific for the endometrial target.