To elucidate the comprehensive transcriptomic dynamics during spontaneous PF development, lung cells from the intact, inflammatory, and fibrotic phases in Ifngr1-/-Rag2-/- mice were analyzed by means of single-cell RNA-sequencing (scRNA-seq), with Rag2-/- mice used as the control (Supplementary Fig. 4a). This evidence concerns the gene RAG2 and pemphigus foliaceus.