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 immunocytochemical 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 ERα, ERβ, differentiation markers (CD68, NCL-MACRO, HAM56), and inflammatory cytokines (interleukin [IL]-1β, tumor necrosis factor-α [TNF-α], IL-6) in PF macrophages was determined. Result(s): The expression of CD68, NCL-MACRO, HAM56, TNFα, IL-6, and IL-1β was significantly higher in PF macrophages obtained from women with endometriosis than in controls. The ERα and ERβ had significantly higher expression in macrophages of women with endometriosis than in controls. A positive correlation was observed between the expression of ERα and ERβ both in women with and without endometriosis. The ERα expression was positively correlated with the expression of inflammatory cytokines in women with endometriosis but not in controls; ERβ expression was correlated to the expression of inflammatory cytokines in the both groups. Conclusion(s): There is a correlation between the expression of ERβ and proinflammatory cytokines both in women with and without endometriosis. The expression of ERα correlates with cytokine production selectively in women with endometriosis but not in controls.