ABSTRACT
【Objective】 To screen the differentially expressed immune genes between responders （Rs） and non-responders （NRs） in chronic hepatitis B patients receiving interferon alpha （IFN-α） treatment and to explore the molecular basis of IFN-α treatment failure. 【Methods】 The gene expression profile GSE27555 which contained 6 Rs and 7 NRs was obtained from the Gene Expression Omnibus （GEO） database； then differentially expressed genes between liver tissues of Rs and NRs were selected by the R software. The iconic immune gene set consisting of 1793 genes was downloaded from the immunology database and analysis portal （ImmPort）. The immune genes were extracted from the differentially expressed genes to obtain the differentially expressed immune genes. Subsequently， Gene Ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analyses of the differentially expressed immune genes were performed by the R software. Protein-protein interaction （PPI） network of the differentially expressed immune genes was constructed using the STRING online tool. The plugin CytoHubba of the Cytoscape software was applied to identify the top 10 genes by using Degree， MCC， MNC， and Closeness algorithms； then the intersection was taken to obtain the hub genes. 【Results】 A total of 88 differentially expressed immune genes， consisting of 13 upregulated and 75 downregulated genes， were identified between Rs and NRs. GO analysis showed that the differentially expressed immune genes were significantly enriched in T cell activation， cell chemotaxis， regulation of cell-cell adhesion， antigen processing and presentation. KEGG pathway analysis suggested that the differentially expressed immune genes were significantly enriched in cytokine-cytokine receptor interactions， Th cell differentiation， antigen processing and presentation， interactions between viral proteins and cytokines and cytokine receptors， chemokine signaling pathways， T cell receptor signaling pathway， IL-17 signaling pathway， natural killer cell-mediated cytotoxicity， Toll-like receptor signaling pathway， and other immune response signaling pathways. The top 7 hub genes， identified by the plugin cytoHubba of the Cytoscape software by using Degree， MCC， MNC and Closeness algorithms， were CD8A， IFNG， CCL2， CCL5， CXCL10， CCL4， and FCGR3A. 【Conclusion】 This study made a comprehensive analysis of the differentially expressed immune genes and signal pathways between Rs and NRs by bioinformatics， and identified 7 Hub genes related to the ineffectiveness of IFN-α treatment in CHB patients. These hub genes may serve as potential biomarkers for predicting the response of IFN-α treatment in CHB patients.