Single nuclear RNA sequencing and analysis of basal cells in pulmonary acute respiratory distress syndrome.

Objective: This study aims to find the gene expression profile specifically in basal cells from pulmonary acute respiratory distress syndrome (ARDSp) patients using single-cell level analysis.

Methods: Single nuclear RNA sequencing (snRNA-seq) data of lung samples, including 18 ARDSp participants and 7 healthy participants, were sourced from the GEO database (GSE171524). The differentially expressed genes (DEGs) were screened by | log2FC | >1 and P < 0.05. Functional enrichment was constructed via Gene Ontology (GO) analysis. Pathway enrichment was conducted via Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The protein-protein interaction (PPI) network of the DEGs was performed via the STRING database. Cytoscape software was employed to find hub genes. The hub genes were sequenced and validated via data set after constructing the rat model of ARDSp.

Results: Using DESeq2 package, 299 genes were disclosed to be downregulated, while 228 were upregulated in ARDSp participants. GO analysis disclosed DEGs were enriched in processes like actin filament organization, regulation of small GTPase-mediated signal transduction, response to unfolded protein, wound healing, and response to oxygen levels. Meanwhile, KEGG analysis disclosed DEGs were involved in protein digestion and absorption, Th17 cell differentiation, iron death, and other biological effects. Ten hub genes, including FN1, HIF1A, HSP90AA1, SMAD3, FOS, CDKN2A, COL1A1, HSPA8, FLNA, and NFKBIA were highlighted based on their network centrality and biological significance. HIF1A, HSPA8, NFKBIA, and CDKN2A were differentially expressed in the validation dataset.

Conclusions: Basal cells in ARDSp exhibit significant changes in gene expression, with ten hub genes identified. Among them, four (HIF1A, HSPA8, NFKBIA, CDKN2A) were validated experimentally using RNA-Seq data from an ARDSp rat model. This study emphasizes the role of basal cells in ARDSp, highlighting the altered gene networks involved in repair and inflammatory responses, providing potential targets for further therapeutic exploration. These findings suggest that alterations in these hub genes may be crucial to basal cell-driven inflammatory and reparative responses in ARDSp.