Cell–cell communication analysis of pbmc of IPF patients highlighted that the CD30 pathway (TNFSF8 and TNFRSF8), CD40 pathway (CD40LG, ITGA5, ITGAM, ITGB1, ITGB2), and FLT3 signaling pathway (FLT3LG and FLT3) play crucial roles in the interactions between CD4+ and CD8+ T cells and other peripheral immune cells among IPF patients (Figure 5‐5/6/7, Supplementary Files 2, KEGG pathway result can be found in Supplementary Files 2). Here, CD4 is linked to idiopathic pulmonary fibrosis.