Liver transcriptome profiles correlates with viral control during hepatitis B virus infection

The natural history of chronic hepatitis B virus (HBV) infection could be divided in different phases by transaminase and HBV replication levels. However, it remains unknown how the intrahepatic transcriptomes in patients are correlated with the clinical phases. Here, we determined the intrahepatic transcriptomes of chronic hepatitis B patients and examined the role of specific groups of genes, including immune-related genes, in the control of hepatitis B virus infection. The transcriptomes of 83 chronic hepatitis B patients (22 immune tolerant, 50 immune clearance, and 11 inactive carrier state) were analyzed by performing microarray analysis of liver biopsies.KEGG pathway analysis showed that immune response genes and interferon-stimulated genes were up-regulated in the immune clearance phase. Although immune tolerant patients and inactive state carriers had significantly different serum viral loads, the hepatic transcriptomes of the two groups were largely similar and only significantly differed in the expression of 109 genes (p < 0.01). Thus, we hypothesized that some of the 109 genes may be involved in HBV control and identified genes of interest by performing systematic screening using specific siRNAs. We showed that silencing candidate genes such as EVA1A resulted in significantly increased viral replication. Conversely, overexpression of candidate genes suppressed virus replication. Conclusions: The immune related pathways were up-regulated in the immune clearance phase but not in the inactive carrier phase. A number of host genes unrelated to immune pathways were expressed in the inactive carrier phase and these may participate in the control of hepatitis B virus replication, resulting in low viral replication.