The Mechanism Research on Inhibition of Japanese Encephalitis Virus Replication by IFN-stimulated Gene 15

• Main Authors: Jiun-Wei Chen, 陳俊瑋
• Other Authors: Nai-Wan Hsiao
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/61984377652564037754

碩士 === 國立彰化師範大學 === 生物技術研究所 === 97 === Type I interferon (IFN)-α and β play an important role in innate immunity to against viral infection through the induction of numerous IFN-stimulated genes (ISGs). IFN- stimulated gene 15 (ISG15), a ubiquitin-like protein, is rapidly induced by IFN-α/β has been reported to be involved to inhibit the replication of NDV, Influenza A Virus, HIV-1, Sindbis Virus, and HSV-1. Japanese encephalitis virus (JEV) that is a mosquito-borne neurotropic flavivirus causes severe central nerve system diseases. We intend to investigate the potential antiviral ability of ISG15 against the JEV infection. Overexpression of ISG15 in human neuronal medulloblastoma TE671 cells significantly reduced the level of JEV-induced cytopathic effect and inhibited the JEV replication about 10 to 100 folds at 24, 48 and 72 hours post infection. In addition, the ISG15 expression reduced the JEV-induced apoptosis and inhibited the NF-κB and p53 activities. Interestingly, the expression of ISG15 increased the responses of JEV-infected cells to the IFN-β treatment, such as the activation of interferon stimulatory response element (ISRE)-luciferase reporter, and the gene expression of IL-6, IL-8, PKR and OAS. Furthermore, Western blotting revealed that the expression of ISG15 significantly increased the phosphorylation level of IRF-3, JAK2 and STAT1 in the JEV-infected cells. Confocal imaging indicated that the translocation of the transcription factors IRF-3 and STAT-1 into nucleus was found in the ISG15- expressing cells post the JEV infection, but in the JEV-infected mock cells. The results elucidated the mechanism of the anti-JEV ability by ISG15, being useful for the clinical application in the treatment against the JEV infection.