P2Y6 Deficiency Enhances Dendritic Cell-Mediated Th1/Th17 Differentiation and Aggravates Experimental Autoimmune Encephalomyelitis

Dendritic cells (DCs) are essential APCs and play a crucial role in initiating and regulating the adaptive immune response. In this study, we have reported that P2Y(6), a member of G protein-coupled receptors, inhibits the maturation and activation of DCs via suppressing the activation of the transcription factor NF-kappa B. Furthermore, loss of P2Y(6) does not impact T cells homeostasis in the steady-state. However, in vitro studies show that P2Y(6) signaling inhibits the production of IL-12 and IL-23 and the polarization of Th1 and Th17 subsets mediated by DCs. In addition, we find that mice lacking P2Y 6 develop more severe experimental autoimmune encephalomyelitis compared with wild-type mice. Our results indicate that P2Y(6) functions as a pivotal regulator on DC maturation, and the loss of P2Y(6) results in the aggravated experimental autoimmune encephalomyelitis, which suggests that P2Y(6) may play a pivotal role in the pathogenesis of autoimmune diseases.