Peritoneal fluid macrophages in endometriosis: correlation between the expression of estrogen receptors and inflammation

Objective: To investigate the expression of estrogen receptors (ERs) and inflammatory cytokines in macrophages obtained from peritoneal fluid (PF) of women with endometriosis. Design: Comparative immumocytochemical study. Setting: University hospital. Patient(s): Thirty women with endometriosis and 22 controls. Intervention(s): The PF samples were collected at laparoscopy. Main Outcome Measure(s): The expression of ER alpha, ER beta, differentiation markers (CD68, NCL-MACRO, HAM56), and inflammatory cytokines (interleukin [IL]-1 beta, tumor necrosis factor-alpha [TNF-alpha], IL-6) in PF macrophages was determined. Result(s): The expression of CD68, NCL-MACRO, HAM56, TNF alpha IL-6, and IL-1 beta was significantly higher in PF macrophages obtained from women with endometriosis than in controls. The ER alpha and ER beta had significantly higher expression in macrophages of women with endometriosis than in controls. A positive correlation was observed between the expression of ER alpha and ER beta both in women with and without endometriosis. The ER alpha expression was positively correlated with the expression of inflammatory cytokines in women with endometriosis but not in controls; ER beta expression was correlated to the expression of inflammatory cytokines in the both groups. Conclusion(s): There is a correlation between the expression of ER beta and proinflammatory cytokines both in women with and without endometriosis. The expression of ER alpha correlates with cytokine production selectively in women with endometriosis but not in controls.