Insights Into Pathogenesis Of Japanese Encephalitis Virus Infection By Quantitative Proteomic Analysis

Japanese encephalitis virus is a main cause of encephalitis in Southeast Asia with above 16 thousand reported cases and 5 thousand mortalities per year.In mainland China,the incidence of deaths is 30% during 2001-2010.Nowadays,although the outbreak of JEV infection is controlled by use of vaccines,epidemical or incidental occurrence of Japanese encephalitis(JE)in developing countries is popular.In fact,not all of infection could cause JE;it is estimated that the ratio of symptomatic to asymptomatic infection is 1:300 to 1:1000.Thus,the data above suggest that host defense plays an important role in the outcome of viral infections,i.e.in determining whether the virus could proceed infection in the central nervous system(CNS).In comparison to protective humoral responses,the innate antiviral immunity,such as the type-I interferon mediated antiviral response,plays a critical role against JEV infection.Notable some of the JEV strains can evade this type-I interferon-mediated antiviral response.Except evasion of antiviral response,progress of JE is also attributed to induction of inflammatory response,which not only cause Blood-Brain Barrier(BBB)damage,but also leads to neuron death.However,by far the mechanisms responsible for the evasion of the type-I interferon response and induction of inflammatory response are not fully understood.The goal of this project is to gain insights into pathogenesis of JE by using iTRAQ proteomics analysis.To fulfil this goal:1.We have set up a mouse model in which JEV infection through intraperitoneal(IP)injection leads to more than 80% mice with symptoms.2.We harvested brain samples from mock-infected mice and JEV-infected mice with symptoms3.We take advantage of iTRAQ proteomics techniques to analyze those brain samples4.We identify the differential expression proteins in comparison to mock-infected samples and validate our proteomic result by western blot5.We perform bioinformatic analysis to identify signaling pathways of those differential expression proteins.6.We use in vitro cell culture to analyze effects of certain molecule on JEV infection.Our major founding are as follows:1.250 proteins were differentially changed after the JEV infection.Out of 250,43 were down-regulated and 207 were up-regulated.2.According to KEGG analysis,JEV infection regulates cytosolic DNA-sensing pathway with induction of TREX1 which has been shown to modulate innate antiviral response.3.Finally,our data demonstrate that TREXl plays an important role in promoting JEV infection.