Characterization of leukocyte subpopulations in the peritoneal fluid of women with endometriosis.

Monoclonal antibodies identifying leukocytes subpopulations were applied to smears of laparoscopically collected peritoneal fluid leukocytes and parallel samples of peripheral blood leukocytes from women with endometriosis (n = 33), those with unexplained infertility (n = 9), and fertile controls (n = 8). Peripheral blood leukocyte profiles in all groups were indistinguishable from reported normal values. Peritoneal fluid leukocyte profiles were observed to be different between groups. The most significant elevations in total leukocytes, macrophages, helper T lymphocytes and natural-killer cells were observed in women with stage I and II endometriosis. Significantly elevated levels of total leukocytes, macrophages, and T lymphocytes were also observed in peritoneal fluid from women with unexplained infertility. The results from this study indicate that the peritoneal environment is immunologically dynamic and suggest that cellular immune mechanisms may contribute to reproductive failure in women with endometriosis and unexplained infertility.