Expression of CD44 in endometrial stromal cells from women with and without endometriosis and its effect on the adherence to peritoneal mesothelial cells

OBJECTIVE: This study was performed to compare the expression of CD44 in endometrial stromal cells (ESCs) of women with and without endometriosis and to evaluate the role of CD44 in the adherence of ESCs to peritoneal mesothelial cells (PMCs). METHODS: A PMC adherence assay was performed to evaluate the adherence of ESCs to PMCs in women with and without endometriosis. The expression of CD44 mRNA was measured by reverse transcription-polymerase chain reaction. CD44 protein was evaluated by Western blot analysis. RESULTS: There were no significant differences in the expression of CD44 mRNA and protein in ESCs or in the binding of ESCs to PMCs between patients with endometriosis and controls. Although the expression of CD44 protein was decreased in both women with endometriosis and controls after anti-CD44 antibody treatment, there was no effect on binding of ESCs to PMCs. Treatment of ESCs with peritoneal fluid from endometriosis patients resulted in a significant increase in binding of ESCs to PMCs compared to untreated ESCs in the endometriosis group. CONCLUSION: This study demonstrates that the expression of CD44 protein in ESCs from women with endometriosis might not be directly associated with adherence to PMCs.