The Peritoneal Fluid Levels of Interleukin‐12 in Women with Endometriosis

PROBLEM: Interleukin-12 (IL-12) is produced mainly by monocytes/macrophages, and it induces proliferation and cytotoxicity of T-cells and natural killer cells. In women with endometriosis, natural killer cell activity in the peritoneal fluid is significantly decreased. We aimed to measure the peritoneal fluid level of IL-12 in endometriosis. METHOD OF STUDY: We measured IL-12 levels in peritoneal fluid samples from women with or without endometriosis and in supernatants from endometrial stromal, ovarian stromal, and mesothelial cell cultures, using a high-sensitivity enzyme-linked immunosorbent assay. RESULTS: The median concentration of IL-12 in the peritoneal fluid of women with endometriosis was 1.1 pg/ml (range, 0.2-5.5) and was 1.6 pg/ml (range, 0.4-2.8) in women without endometriosis, not a statistically significant difference. IL-12 was not detected in the supernatants of endometrial stromal, ovarian stromal, and mesothelial cell cultures. CONCLUSION: Concentrations of IL-12 in the peritoneal fluid of women with or without endometriosis are low, but they are detectable and are not affected significantly by the presence of endometriosis.