As shown in Fig. 3, the percentages of aTregs in CD4+ T cells were negatively correlated with DLCO predicted values (r = −0.475, p = 0.016; Fig. 3a) but not with FVC % predicted values (r = −0.257, p = 0.225; Fig. 3b) in IPF patients. This evidence concerns the gene CD4 and idiopathic pulmonary fibrosis.