Fig. 1

scRNA-seq analysis of PAH lung tissue reveals cellular heterogeneity and key gene expression differences between PAH patients and healthy controls. A Schematic representation of the scRNA-seq analysis process. Lung tissue samples were collected from PAH patients and healthy controls, and multiple publicly available datasets (GSE254617, GSE210248, GSE233189, and GSE228643) were integrated for analysis. Single cells from these samples were sequenced to explore gene expression patterns across various cell types, enabling a detailed investigation of cellular and molecular changes associated with PAH. B UMAP plot showing clusters of different cell types identified in the lung tissue samples, with each color representing a unique cell type: SMC, Fib, endothelial cells, epithelial cells, B cells, T cells, and myeloid cells. C UMAP plots (bottom) show the distribution of cell types and their respective proportions in PAH and control groups, highlighting the shifts in cell type composition within diseased tissue. D Heatmap depicting differentially expressed genes across cell types, with pathways significantly enriched in PAH patients annotated on the right. Enrichment terms include pathways related to cell migration, inflammation, vascular remodeling, and immune response, suggesting critical molecular processes that may be driving PAH pathogenesis. The bar plots on the right indicate the number of differentially expressed genes associated with each pathway, grouped by cell type. E Cell proportion analysis: The table illustrates the relative proportions of each cell type in PAH and Con, highlighting notable changes in cellular composition associated with PAH pathology