The complement system and endometriosis: what's new?

Abstract

The objective of this literature review was to reveal new noninvasive markers of the complement system for improvement of endometriosis (EM) diagnostics. To analyze scientific literature, the international database was used.
 Among women with EM, a significant increase in the blood serum С1, С1-INH, C3c and С4 levels and elevated concentrations in the peritoneal fluid was observed. However, iC3b level in EM women was significantly lower in the peritoneal fluid and blood serum compared with healthy women. The levels of C4A/B gene expression were higher in the ectopic tissues than in the eutopic endometrium. The membrane attack complex (MAC) concentration was higher in the peritoneal fluid and blood serum among women with disseminated stage of EM compared to the control group. In women with EM, an increased level of mannose-binding lectin (MBL) in the peritoneal fluid was noted; a higher concentration was observed at the early stage of EM (stages I and II AFS) in comparison with the disseminated one (stages III and IV AFS). The development of new and improvement of the existing noninvasive markers of the complement system can be perspective for noninvasive diagnostics of EM and determination of the degree of its severity.