Inhibition of HBV replication by EVA1A via enhancing cellular degradation of HBV components and its potential therapeutic application

Hepatitis B virus (HBV) DNA is much higher during HBeAg-positive chronic HBV infection (EP-CBI) than during HBeAg-negative chronic HBV infection (EN-CBI), although the necroinflammation in liver is minimal and the adaptive immune response is similar in both phases. We previously reported that mRNA levels of EVA1A were higher in EN-CBI patients. In this study, we aimed to investigate whether EVA1A inhibits HBV gene expression and examine the underlying mechanisms. The available cell models for HBV replication and model HBV mice were used to investigate how EVA1A regulates HBV replication and the antiviral activity based on gene therapy. The signaling pathway was determined through RNA sequencing analysis. The results demonstrated that EVA1A can inhibit HBV gene expression in vitro and in vivo. In particular, EVA1A overexpression resulted in accelerated HBV RNA degradation and activation of the PI3K-Akt-mTOR pathway, two processes that directly and indirectly inhibiting HBV gene expression. EVA1A is a promising candidate for treating chronic hepatitis B (CHB). In conclusion, EVA1A is a new host restriction factor that regulates the HBV life cycle via a nonimmune process.