GPER1 and autoimmune disease: Recent studies have revealed that GPER plays an important role in regulating immune responses in autoimmune diseases, possibly by promoting the secretion of interleukin (IL)-10 and amplifying Treg cells, thereby inhibiting the Th17 cell–mediated immune response, which can be inhibited by activating the GPER-direct antagonist G15 and inhibiting the GPER agonist G1 receptors [29–32].