Project description:Powassan virus (POWV), a vector-borne pathogen transmitted by Ixodes ticks in North America, is the causative agent of Powassan encephalitis. As obligate hematophagous organisms, ticks transmit pathogens like POWV at the tick bite site, specifically during the initial stages of feeding. Tick-feeding and salivary factors modulate the host's immunological responses, facilitating blood feeding and pathogen transmission. However, the mechanisms of immunomodulation during POWV transmission remain inadequately understood. In this study, we investigated the global cutaneous transcriptomic changes associated with tick bites during POWV transmission. We collected skin biopsies from the tick attachment sites at 1-, 3-, and 6-hours post-feeding by POWV-infected and uninfected ticks, followed by RNA sequencing of these samples. Differentially expressed genes were analyzed for pathway enrichment using gene ontology and pathway enrichment analyses. Our findings reveal that tick feeding alone significantly impacts the skin transcriptome within the first 1 to 3 hours of tick attachment. Although early POWV transmission induces minimal changes in the local environment, a pronounced shift toward a proinflammatory state is observed 6 hours post tick attachment, characterized by neutrophil recruitment and interleukin signaling. These transcriptomic data elucidate the dynamic changes at the tick bite site, transitioning from changes that assist blood meal acquisition to a proinflammatory phase that may facilitate viral dissemination.

2025-02-05 | GSE282786 | GEO

Genotype-Driven Sensitivity in Mice to Tick-Borne Encephalitis Virus Correlates with Differential Host Responses in Peripheral Macrophages and Brain

Project description:Tick-borne encephalitis (TBE) is the most common tick-borne viral infection in Eurasia, with outcomes ranging from asymptomatic to fatal encephalitis. While the reasons for this variability are unclear, host genetics likely plays a role. Our previous research showed that BALB/c mice have intermediate susceptibility to TBE virus (TBEV), STS mice are highly resistant, and the recombinant congenic strain CcS-11, which has 12.5% of the STS genome on the BALB/c background, is more susceptible than the BALB/c. In this study, we used these three mouse strains to investigate the host response to TBEV infection in both peripheral macrophages, one of the initial target cell populations, and in the brain, the terminal target organ for the virus.

2025-02-05 | GSE276086 | GEO

Differences in Genetic Diversity of Tick-Borne Flaviviruses

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.

2023-12-04 | E-MTAB-12112 | biostudies-arrayexpress

Single-cell transcriptomic profiling of brain immune infiltration following Venezuelan equine encephalitis virus infection

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.

2024-12-09 | GSE274566 | GEO

Japanese encephalitis virus

Project description:Japanese encephalitis virus Genome sequencing

| PRJNA871976 | ENA