Dengue virus (DENV) is a single-stranded positive-sense RNA virus, transmitted to humans by mosquito vectors. There are four distinct circulating serotypes of DENV, and together they are estimated to infect 390 million people per year. Stable infection of the common DENV vector Aedes aegypti with the insect endosymbiotic bacterium Wolbachia has been demonstrated to limit the ability of A. aegypti to support DENV replication, but the mechanism is unresolved.
Previous studies indicate that the DENV serotypes differ in the degree to which they are inhibited by Wolbachia infection of A. aegypti 1. However, the specific contribution of DENV genome sequence variation has not been directly examined. Using a panel of DENV serotype 2 (DENV-2) strains, we have compared intra-serotype differences in blocking by Wolbachia. Our data indicate that titres of a variety of DENV-2 strains are reduced in an A. aegypti cell line infected with Wolbachia compared to titres produced in the parental cell line (without Wolbachia). Additionally, we have performed experimental evolution experiments to examine the ability of DENV-2 to adapt within these cell lines with serial passaging. These data will be used together with next generation sequencing techniques to identify regions of the DENV genome that confer resistance/susceptibility to Wolbachia-mediated inhibition.