Relationship between apoptosis and the number of macrophages in eutopic endometrium from women with and without endometriosis

Objective: To investigate the relationship between apoptotic cells and macrophages in the eutopic endometrium of women with and without endometriosis. Design: Retrospective analysis of archival uterine endometrial biopsy specimens. Setting: Institute for the Study and Treatment of Endometriosis, and university-based pathology and research laboratories. Patient(s): Fifty-one women with endometriosis and 24 healthy control subjects without endometriosis. Intervention(s): None. Main Outcome Measure(s): The number of TUNEL+ (terminal deoxynucleotide transferase [TdT]-mediated deoxyuridine triphospate [dUTP] nick end-labeling-positive) (apoptotic) cells and CD68+ (CD68 positive) (macrophages). Result(s): Apoptotic cells and macrophage numbers were positively correlated in the eutopic endometrium of women with and without endometriosis. However, the number of apoptotic cells and the macrophage content in the endometrium of women with endometriosis was significantly reduced compared with that of healthy control subjects without endometriosis. Differences between apoptosis and macrophage numbers between the two populations were observed predominantly during the early proliferative phase of the menstrual cycle. Conclusion(s): The reduction in apoptosis described for endometrial cells in women with endometriosis may be related to reduced macrophage trafficking into the eutopic endometrium during the early-proliferative phase of the menstrual cycle.