Project description:There are very few studies exploring the genetic diversity of tick-borne encephalitis complex viruses. Most of the viruses have been sequenced using capillary electrophoresis, however, very few viruses have been analyzed using deep sequencing to look at the genotypes in each virus population. In this study, different viruses and strains belonging to the tick-borne encephalitis complex were sequenced and genetic diversity was analyzed. Shannon entropy and single nucleotide variants were used to compare the viruses. Then genetic diversity was compared to the phylogenetic relationship of the viruses.
Project description:Neurotropic alphaviruses such as Venezuelan equine encephalitis virus (VEEV) are critical human pathogens that continually expand to naïve populations and for which there are no licensed vaccines or therapeutics. The neuropathology of VEEV has been attributed to the immune response in the brain yet the underlying mechanisms and specific immune cell populations involved are not fully elucidated. In this study, a murine model of lethal VEEV infection is paired with single-cell RNA sequencing to transcriptionally profile the immune response longitudinally in the brain following infection. Infection-induced immune changes in the brain was also compared to changes in peripheral blood mononuclear cells (PBMCs). The results define an inflammatory response involving transcriptionally distinct subpopulations of activated microglia and infiltrating proinflammatory myeloid populations and cytotoxic lymphocytes. This study advances our understanding of the immune mechanisms underlying viral encephalitis toward the goal of identifying new therapeutic targets.
Project description:Zika virus (ZIKV) is a mosquito-transmitted positive-sense RNA virus in the family Flaviviridae. Live attenuated vaccines have been successfully used to combat infection by flaviviruses, such as yellow fever and Japanese encephalitis viruses. A Zika virus harboring combined mutations in the envelope protein glycosylation site and in the nonstructural 4B protein amino acid 36 (ZE4B-36) was generated and assessed for stability, attenuation, and protection against infection. To determine the genetic stability of its RNA genome, ZE4B-36 was serially passaged in vitro in Vero cells. Virus harvested from passages (P)1 to P6 was subjected to next generation sequencing and downstream analysis to determine its nucleotide sequence variability. Specifically, single nucleotide variant analysis showed that the ZE4B-36 genome decreased its genetic diversity and resulted in a more stable nucleotide sequence. Thus, in addition to showing attenuation and protection, ZE4B-36 is a stable live attenuated virus that possesses characteristics important for a vaccine to combat Zika disease.
