The Tyrosine Phosphatase Activity of PTPN22 Is Involved in T Cell Development via the Regulation of TCR Expression

The protein tyrosine phosphatase PTPN22 inhibits T cell activation by dephosphorylating some essential proteins in the receptor (TCR)-mediated signaling pathway, such as lymphocyte-specific kinase (Lck), Src family kinases Fyn, and phosphorylation levels of Zeta-chain-associated kinase-70 (ZAP70). For first time, we have successfully produced CS transgenic mice which activity is suppressed. Notably, number thymocytes was significantly reduced, expression cytokines spleen lymph nodes changed significantly. Furthermore, facilitated positive negative selection developing thymocytes, increased TCRαβ-CD3 complex on thymus surface, regulated their internalization recycling. ZAP70, Lck, Phospholipase C gamma1(PLCγ1), other were observed to be reduced mouse thymocytes. In summary, regulates TCR recycling via modulation pathway affects surface regulate selection. affected development thymus, spleen, nodes, peripheral immune organs mice. Our study demonstrated that plays a crucial role provides theoretical basis for system construction.