NK Cell Profiling: Expression of TIGIT and LAG3 as Immune Checkpoints in Advanced Endometriosis.

PROBLEM: Endometriosis (EMS) is a gynecological condition that is associated with chronic pelvic pain and inflammation. Evidence supports the idea that natural killer (NK) cell dysfunction contributes to EMS pathogenesis; nevertheless, the role of T cell immunoreceptors with Ig and ITIM domains (TIGIT) and lymphocyte activation gene 3 (LAG3) in the development of endometriosis-associated immunological abnormalities is not yet reported.

METHOD OF STUDY: The present study used multicolor flow cytometry to compare the frequency of NK cells expressing TIGIT and LAG3 in the peripheral blood (PB) and peritoneal fluid (PF) of women with and without endometriosis. The levels of soluble form of LAG3 (sLAG3) were compared between EMS and non-EMS participants in both PB and PF.

RESULTS

The number of NK cells expressing TIGIT increased in the PF of EMS compared to the other benign gynecological conditions (OBGC) (Pv = 0.0089); however, this difference was not statistically significant in PB. In contrast, an increased frequency of LAG3+NK cells was detected in both PF and PB in EMS compared to the controls. Additionally, a higher level of sLAG3 was stated in both the PB and PF of EMS patients.

CONCLUSIONS

An impaired number of TIGIT+ and LAG3+NK cells was detected in the peritoneal microenvironment of EMS, which may be responsible for impaired immune surveillance, promoting the survival of ectopic lesions, and contributing to the evolution of EMS.