Behaviour of Cytokine Levels in Serum and Peritoneal Fluid of Women with Endometriosis

Abstract

Endometriosis is a disorder characterised by presence and growth of endometrial tissue outside the uterus, primarily into the peritoneum. The peritoneal fluid (PF) of women with endometriosis undergoes a number of biological changes, including local inflammatory-reparative phenomena and peripheral blood mononuclear cells (PBMC) involvement. These activated cells as well as the endometriotic cells secrete various cytokines with pleiotropic biological activities. Dynamic interplay among cytokines may contribute to realise a favourable microenvironment for the implantation of endometrial cells and the progression of the disease. In the present study, we evaluated the levels of cytokines, such as the tumour necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), interleukin-8 (IL-8) and monocyte chemotactic protein-1 (MCP-1) in PF and in serum (S) of women with endometriosis to compare their behaviour in both biological fluids. The patients (n = 26) were women of reproductive age attending our observation centre for infertility, diagnosed endometriosis at laparoscopy. Control group (n = 5) consisted of women affected by non-immunologic infertility, diagnosed by explorative laparoscopy. S samples were obtained from peripheral blood before anaesthesia and laparoscopy. PF samples were collected at the time of laparoscopy. Both biological fluids were examined for cytokine by ELISA assays. Our results showed that S and PF levels of TNF-α, not dosable in controls, were very high at the early stage and decreased significantly with the severity of the disease (p < 0.001). TGF-β levels were significantly (p < 0.001) higher than in controls and increased with the severity of the disease (p < 0.001), particularly in the PF. S and PF IL-8 as well as MCP-1 concentrations at all stages were higher than in controls (p < 0.001), yet showed an opposite behaviour in both biological fluids. In fact, S levels of IL-8 and MCP-1 were significantly (p < 0.001) higher at early stages and decreased with the severity of the disease, whereas we observed a significant (p < 0.001) enhancement of these chemokine levels in PF from stage I to stage II and stage III. These observations showed that TNF-α and TGF-β levels were overlapping in S and PF of women with endometriosis. On the contrary, MCP-1 and IL-8 S concentrations decreased with the severity of the disease, whereas PF levels showed markedly increased at severe stages. Taken together the observed changes may be due both to the increased peritoneal macrophage activity and to the larger recruitment of PBMC and autocrine release by endometriotic cells.

Th1 and Th2 immune responses related to pelvic endometriosis

“…Increased concentrations of TNF-alpha have already been described in relation to advanced stages 32 , initial stages 33 and in cases where no relation could be perceived with the stage of endometriosis 34 . Concerning deep endometriosis, statistical analysis showed no significant difference in cytokine concentrations.…”

Simultaneous Measurement of 25 Inflammatory Markers and Neurotrophins in Neonatal Dried Blood Spots by Immunoassay with xMAP Technology

“…Because no reference methods have been published for the measurement of cytokines in serum and blood and because of the large variations in serum concentrations reported in the literature, it is difficult to evaluate the absolute concentrations reported by the present multiplex method (8,16,34,(42)(43)(44)(45)(46)(47)(48). However, to the best of our knowledge the cytokine concentrations measured in sera from healthy people fell within the ranges reported by several other assays, i.e., for IL-1␤, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IL-17, IL-18, IFN-␥, TNF-␣, GM-CSF, and MCP-1 (35, 45, 49 -54 ) (60,61 ).…”

Diesel Exhaust Exposure Enhances the Persistence of Endometriosis Model in Rats

“…Serum MCP-1 level is increased in rats with endometriosis in comparison to those without endometriosis. 20) Several clinical researchers reported that serum MCP-1 is higher in women with endometriosis than in those without [26][27][28] and suggested its usefulness as a biomarker for nonsurgical prediction of endometriosis in humans. 29) Gmyrek et al 27) reported that serum MCP-1 level in women with endometriosis was correlated with severity of the disease.…”