Objectives: Tumor necrosis factor-alpha (TNF-alpha) plays a key role in the processes underlying the development of pelvic endometriosis. TNF-alpha acts on target cells via two receptors: TNFR1(p55) and TNFR2(p75). Depending on cell type and its activation state, ligand binding to TNF-alpha may induce activation and proliferation of the cells or promote apoptosis. The aim of our study has been to evaluate the expression of TNFR1 and TNFR2 on peritoneal fluid macrophages and T lymphocytes derived from women with endometriosis.
Material and methods: The study group consisted of 22 patients with endometriosis (stage I and II rAFS). 14 patients with benign, non-inflammatory ovarian tumors composed the reference group. Mononuclear cells have been isolated from peritoneal fluid, obtained during laparoscopy. The expression of TNFR1 and TNFR2 proteins has been evaluated by means of flow cytometry, using monoclonal antibodies against CD120a, CD120b, CD3 and CD14.
Results: The percentage of peritoneal fluid macrophages revealing the expression of TNFR1 and TNFR2 proteins has been higher in patients with endometriosis, in comparison with control group (22.6+/-5.3% vs. 6.8+/-1,8%; p=0.03 and 29.3+/-2.3% vs. 8.8+/-1.8%; p=0.01, respectively). The percentage of T lymphocytes with the expression of TNFR1 and TNFR2 has been similar in endometriosis and control group.
Conclusion: Higher percentage of peritoneal fluid macrophages expressing TNFR1 and TNFR2 proteins in endometriosis suggests dependence of these cells on TNF-alpha stimulation. Changes in TNF receptors distribution on PF macrophages, but not lymphocyte, may play its role in the pathogenesis of endometriosis.