Hedgehog Induced ZFYVE21 Activates T Cell Intrinsic, NLRP3 Inflammasomes to Promote Chronic Inflammation

ZFYVE21 is a novel Rab5 effector involved in immune signaling whose functions in vivo are undefined. Using humanized mouse models and patient specimens, we describe a T cell-autonomous role for ZFYVE21 in promoting chronic inflammation. Following ischemia reperfusion injury (IRI), endothelial cells (ECs) produce Hedgehog (Hh) ligands. Hh ligands induce expression of ZFYVE21 in a “Ptchhi” cell population (CD3+CD4+CD45RO+Ptch1hiPD-1hi) that is highly responsive to Hh signaling and which display vigorous EC-mediated recruitment and effector responses in vivo. Mechanistically, following IFN-gamma-dependent priming, Hh-induced ZFYVE21 modulates T cell intrinsic, NLRP3 inflammasome activity in an Akt-dependent manner to allow IL-18-mediated potentiation of IFN-gamma responses. Hh-induced NLRP3 inflammasomes and T cell-specific ZFYVE21 augment vascular sequelae of chronic inflammation. Moreover, Ptchhi T cells highly expressing ZFYVE21 are expanded in IRI patients, and frequencies of these cells are modulated by Hh signaling. Hh-induced ZFYVE21 activates T cell intrinsic, NLRP3 inflammasomes to promote chronic inflammation. Overall design: To do this, Tmem from 4 donors were stimulated with anti-CD3 in the presence of either anti-CD28 or SAG, and the P1-P4 populations emerging from these treatments were FACS-sorted for RNA sequencing.