Location: Location not imported yet.Title: Japanese encephalitis virus infects novel Culex cell line
Submitted to: Meeting Abstract
Publication Type: Other
Publication Acceptance Date: 4/16/2020
Publication Date: N/A
Technical Abstract: Japanese encephalitis virus (JEV) is the leading cause of human viral encephalitis in Asia. Transmission of JEV is mediated by Culex mosquitoes with water birds being a primary reservoir and pigs serving as an amplifying host. While JEV transmission has not occurred in the United States, some North American Culex mosquitoes are competent vectors and North American domestic pigs are susceptible to experimental infection. This suggests that JEV introduction and spread into the United States is possible. The studies with JEV infection primarily require biosafety laboratory (BSL)-3 space, thereby limiting the laboratories that can examine the virus interaction with North American vector and host species. An exception to this is the SA-14-14-2 vaccine strain of JEV which can be safely studied in cell culture at BSL-2. While previous studies utilizing the vaccine strain used an Aedes cell line (C6/36) for viral infections, this study examines the ability of the vaccine strain to infect cell lines derived from Culex mosquitoes. Two Culex cells lines derived from species known to be susceptible to JEV infection were utilized. These cell lines include Hsu cells (derived from Culex quinquifasciatus) and a novel cell line created at the Arthropod-Borne Animal Disease Research Unit of USDA, derived from Culex tarsalis (CxTr). The vaccine strain of JEV infected CxTr with an average titer of 5.7 Log10 which was approximately 35 times lower than the average titer of C6/36. Compared to BHK and C6/36 cells which demonstrated cytopathic effect at 3- and 5-days post infection (dpi), the CxTr cell lines did not have CPE at 5 dpi. Preliminary studies with Hsu, demonstrated a variable infection that resulted in much lower titers than those found in the CxTr cell line. These data demonstrate that the novel cell line from Culex mosquitoes can be infected with JEV. In addition, this system could be used as a surrogate for the more virulent viruses in studies examining the molecular mechanisms of the virus-vector interaction important for replication and maintenance in the Culex mosquitoes.