Objective: Murine endometrial granulocyte-macrophage colony-stimulating factor has been related to macrophage recruitment and activation and postulated to mediate reproductive events. This study was designed to determine whether granulocyte-macrophage colony-stimulating factor is present in normal human endometrium or endometriosis.
Study design: Granulocyte-macrophage colony-stimulating factor was immunohistochemically evaluated in matched endometrial and endometriosis biopsy specimens (n = 19) and endometrial biopsy specimens from disease-free patients (n = 8). Staining differences were determined with McNemar's, Fisher's, and Wilcoxon's tests.
Results: Granulocyte-macrophage colony-stimulating factor was primarily localized in endometrial and endometriotic epithelial cells. Expression (p = 0.71) and staining intensity (p = 0.37) was similar in matched proliferative-phase endometrium and endometriosis. Matched secretory-phase endometrium and endometriosis also expressed granulocyte-macrophage colony-stimulating factor in similar proportions (p = 0.12), but staining intensity was enhanced in secretory endometriosis compared with secretory endometrium (p = 0.05). Endometrial granulocyte-macrophage colony-stimulating factor did not vary throughout the menstrual cycle, but endometriotic expression (p = 0.013) and staining intensity (p = 0.008) were significantly greater in the secretory phase.
Conclusions: Granulocyte-macrophage colony-stimulating factor is localized in endometrial and endometriotic epithelial cells with increased expression in secretory-phase endometriosis. Granulocyte-macrophage colony-stimulating factor may elicit migration, proliferation, and activation of endometrial and peritoneal macrophages.