Abstract：Objective: To screen potential key genes (Hub genes) and pathways involved in the pathogenesisof bronchiolitis in children caused by respiratory syncytial virus (RSV) subtype A using RNA sequencing data analysis, aiming to provide scientific clues for intervention and treatment of RSV bronchiolitis. Methods: Twentythree patients with RSV bronchiolitis (case group) and ten healthy children (healthy control) were enrolled.RNA was extracted from peripheral blood leukocytes for high-throughput RNA sequencing. The differentially expressed genes (DEGs) between case and control were obtained by three R packages including DESeq2, edgeR and limma. All DEGs were selected for GO and KEGG enrichment analysis by “clusterProfiler” package and Metascape tool, respectively. Protein-protein interaction (PPI) analysis for all DEGs was constructed using STRING database, and finally Hub genes were identified in Cytoscape software. Results: We screened a total of 286 DEGs between case and control, including 166 upregulated genes and 120 downregulated genes. GOenrichment analysis showed that these DEGs were mainly enriched in several biological processes including hydrogen peroxide catabolic process, cellular response to biotic stimulus and vitamin D receptor signaling pathway. KEGG pathway analysis showed that these DEGs were mainly involved in several pathways related to immune response, such as cytokine signaling in immune system, adaptive immune system and neutrophildegranulation. Using the MCODE plug-in of Cytoscape, we determined four core modules from entire PPI network, mainly associated with viral protein interaction with cytokine and cytokine receptor, and RAF/MAP kinase cascade. Finally, we screened a total of 11 Hub genes related to RSV subtype A bronchiolitis, including RRM2, BUB1B, BUB1, MCM10, CDC45, MKI67, ASPM, NCAPG, NUSAP1, ESPL1 and CDT1. Conclusion:These immune characteristics and hub genes may be correlated with the pathogenesis of RSV bronchiolitis in children, and the specific pathogenic mechanism deserves further investigation.
