Detection of antiendometrial antibodies in patients with endometriosis by cell ELISA

PROBLEM: To determine whether infertile patients with endometriosis have serum antiendometrial antibodies. METHODS: Sera from 40 infertile patients with or without endometriosis were tested by cell enzyme-linked immunosorbent assay (ELISA), in which endometrial cancer cells were used as endometrial antigens, and uterine cervix cancer cells as control antigens. As a negative control, eight healthy adult males were included. The level greater than the mean + 2 standard deviations (SD) of the male control group was judged positive. RESULTS: The mean value of antiendometrial antibody level was significantly higher in patients with endometriosis than in those without endometriosis (ANOVA, P < 0.01). The frequency of antiendometrial antibody-positive patients was also higher in the former than in the latter (χ2 test, P < 0.05). However, when uterine cervix cancer cells were used as antigens, no difference was observed in the mean antibody levels or in the positive rates between the two groups. CONCLUSIONS: Endometriosis seems to be associated with autoantibody production against the endometrium-related antigen(s).