Figure 1.

(A) A pro-endometriotic microenvironment produced by an existing endometriotic lesion provides the appropriate micro-environment for the progression of this disorder. After the buildup of cells by a previously established lesion, these elements show distinctive features that destroy immune surveillance (96). (B) H19 levels have been shown to be decreased in the PBMCs of patients with endometriosis. This is accompanied with an increase in miR-342-3p levels. This miRNA binds with the 3′ UTR of IER3, thus inhibiting its expression (93). IER3 participates in proteasomal degradation of IF-1. Decrease in the levels of IF-1 leads to increase in reactive oxygen species (ROS) levels (97). ROS increases active extracellular TGF-β levels. This cytokine influences RORγt, thus activating transcription of IL-17 and leading to differentiation of TH17 cells (98).