Next, to determine the antigen-specific recognition of CAR-cTregs by both activation (Figure 2D and Supplemental Figure 4, A and B) and proliferation (Figure 2F) and the secretion of Th1/2 cytokines (Figure 2G), we utilized aFibs induced by TGF-β1 to emulate the FAP1+ AF1 population in IPF. This evidence concerns the gene PTPN13 and idiopathic pulmonary fibrosis.