Mitogen induced production of polyclonal IgG is decreased in women with severe endometriosis

PROBLEM: The etiology and/or pathogenesis of endometriosis may involve aspects of both humoral and cellular immunity. METHOD: In this investigation, we analyzed the ability of B lymphocytes from distinct patient groups for production of IgG1, IgG2, and IgG3 following in vitro stimulation with polyclonal B-cell mitogens (pokeweed mitogen and Staphylococcus aureus Cowan strain I) after in vitro stimulation with polyclonal B-cell activators. RESULTS: We observed that the in vitro production of IgG1, IgG2, and IgG3 was identical among fertile controls (no endometriosis; N = 22), infertile women without endometriosis (N = 22), infertile women without endometriosis (N = 20) and patients with stage 1 or 2 endometriosis (N = 31). In contrast, in vitro IgG2 production was significantly reduced among women with stage 3 or 4 endometriosis (N = 11) compared to controls (P < 0.001). CONCLUSION: Since the number of circulating B cells was similar in each patient group studied, the reduced production of IgG2 in patients with stage 3 or 4 disease was not merely due to fewer antibody producing cells in those subjects, and we speculate that the observed decrease in polyclonal IgG2 production among these patients is due to a primary defect. In additional studies, we observed that polyclonal IgG2 production was normal among stage 3 or 4 patients treated with danazol (N = 11), but significantly reduced in patients treated with gonadotropin releasing hormone agonists (N = 8). Although not conclusive, these data suggest that danazol may have the capacity to correct the defective production of polyclonal IgG2 in patients with severe endometriosis.