Microvesicles released from ectopic endometrial foci as a potential biomarker of endometriosis

Objectives: Angiogenesis is engaged in endometriosis. It is regulated by regulatory factors and cytokines, transported in microvesicles. The purpose was to investigate the presence of MVs with vascular endothelial growth factor (VEGF) and metalloproteinase-9 (MMP-9) in peripheral blood and peritoneal fluid of women operated on for endometrioma or teratoma Material and methods: Microvesicles (MVs) were determined in blood samples and peritoneal fluid samples collected from women aged 20–60 years operated on for endometriosis (test group) and teratoma (control group). The final investigations were performed on 47 patients, who qualified for the study based on the meticulous inclusion criteria. MVs were analyzed by flow cytometry (FACS) using annexin V, antibodies for molecules characteristic of cells from endometriosis foci (keratin 18 (K18), CD105, CD146), and antibodies for intraepithelial vascular growth factor VEGF and metalloproteinase-9 (MMP-9). The sample was double “reading” using flow cytometry (FACSCantoII). Results: Cytometry analysis confirmed MVs’ presence in plasma and peritoneal fluid collected from patients with both endometriosis and teratomas. A statistically significant higher level of AnnexinV (+) MVs were observed in plasma samples of endometriosis patients. In the control group, there was a higher percentage of double-positive VEGF (+)/MMP-9 (+) and single MMP-9 (+) positive MVs in the serum. In the peritoneal fluid higher frequency of double-positive VEGF (+)/MMP-9 (+) MVs were found in the control group. However, the amount of VEGF (+) / MMP-9 (+) MVs object did not enable to differentiate between the test and control groups. The study was the first, in which MVs were confirmed in plasma and peritoneal fluid in benign adnexa tumors. Conclusions: Microvesicles are present in peripheral blood and peritoneal fluid samples collected from patients with endometriosis and teratomas. Microvesicles with proangiogenic factors (VEGF and MMP-9) are more abundant in blood and peritoneal fluid samples from patients with teratomas