Project description:The mpox outbreak of 2022–2023 involved rapid global spread in men who have sex with men. We infected 18 rhesus macaques with mpox by the intravenous, intradermal, and intrarectal routes and observed robust antibody and T cell responses following all three routes of infection. Numerous skin lesions and high plasma viral loads were observed following intravenous and intradermal infection. Skin lesions peaked on day 10 and resolved by day 28 following infection. On day 28, we re-challenged all convalescent and 3 naive animals with mpox. All convalescent animals were protected against re-challenge. Transcriptomic studies showed upregulation of innate and inflammatory responses and downregulation of collagen formation and extracellular matrix organization following challenge, as well as rapid activation of T cell and plasma cell responses following re-challenge. These data suggest key mechanistic insights into mpox pathogenesis and immunity. This macaque model should prove useful for evaluating mpox vaccines and therapeutics.
Project description:We sorted macrophages (known to be infected by influenza viruses from the lungs of mice infected with MA-Venus-PR8 on the basis of their fluorescent protein expression and performed microarray analysis. Macrophages isolated from the lungs of mice inoculated with PBS (naive macrophages) served as controls.
Project description:We sorted macrophages (known to be infected by influenza viruses from the lungs of mice infected with MA-Venus-PR8 on the basis of their fluorescent protein expression and performed microarray analysis. Macrophages isolated from the lungs of mice inoculated with PBS (naive macrophages) served as controls. 15 samples
Project description:The high mutation rate of HIV is linked to the generation of viruses expressing proteins with altered function whose impact on disease progression is unknown. We investigated the effects of HIV-1 viruses lacking Env, Vpr and Nef on CD4+ T cell gene expression using high-density DNA microarray analysis and functional assays. Keywords: three independent donors
Project description:The high mutation rate of HIV is linked to the generation of viruses expressing proteins with altered function whose impact on disease progression is unknown. We investigated the effects of HIV-1 viruses lacking Env, Vpr and Nef on CD4+ T cell gene expression using high-density DNA microarray analysis and functional assays. Experiment Overall Design: Human activated CD4+ T-lymphocytes from three independent donors were infected with HIV-1 viruses that lack Env and Nef (pNL4-3.eGFP.R+E- or HIVD2GFP) or Env, Vpr and Nef. (pNL4-3.eGFP.R-E- or HIVD3GFP) were pseudotyped with VSVG envelope. As a control, CD4+ T-lymphocytes were infected with VSVG-pseudotyped eGFP. CD4+ T-cells were sorted 48 hours after infection using GFP as a marker of infectivity. RNA was isolated 10 hours after sorting, labeled, and prepared for microarray analysis.
Project description:Modified vaccinia Ankara (MVA) immunisation is being deployed to curb the current outbreak of mpox in multiple countries1. Originally authorized for vaccination against smallpox, MVA is a vaccinia virus (VACV) strain that does not replicate in human cells or cause serious adverse events. Here, we conducted a highly multiplexed proteomic analysis2 to quantify >9,000 cellular proteins and ~80% of viral proteins at five time points throughout MVA infection of human cells3. 690 human proteins were down-regulated >2-fold by MVA, revealing a substantial remodelling of the host proteome. >25% of these MVA targets, including multiple components of the nuclear pore complex (NPC), were not shared with VACV-Western Reserve4, which is derived from a first generation smallpox vaccine associated with serious adverse events. Using pharmacological inhibition of viral DNA replication and heat-inactivated virions, we discovered that post-replicative gene expression is necessary for the downregulation of NPC proteins and for elements of MVA antagonism of innate immune sensing. Our approach thus provides the first global view of the impact of MVA infection on the host proteome, offers insights into how MVA interacts with the antiviral defences and identifies cellular mechanisms that may underpin the abortive infection of human cells. These discoveries will prove vital to the rational design of future generations of vaccines.
Project description:Severe fever with thrombocytopenia syndrome virus (SFTSV) is an emerging tick-borne bunyavirus that causes severe clinical symptoms and mortality in humans. Haemaphysalis longicornis tick has been identified as the competent vector for SFTSV transmission. Although antiviral RNA interference (RNAi) in insects has been well documented, the degree to which RNAi contributes to antiviral defense in ticks is still largely elusive. In this study, utilizing arthropod-borne RNA viruses, including SFTSV, we find abundant virus-derived small interfering RNAs (vsiRNAs) are induced in H. longicornis after infection through either microinjection or natural blood-feeding. Furthermore, we identify a Dicer2-like homolog, the core protein of antiviral RNAi pathway, in H. longicornis and knocking down this gene exacerbated virus amplification. To counteract this antiviral RNAi of ticks, viruses have evolved suppressors of RNAi (VSRs). Here, we show that reduced viral replication inversely correlated with the accumulation of vsiRNAs in ticks after infection with recombinant sindbis virus (SINV) expressing heterologous VSR proteins. Elucidating the antiviral RNAi pathway of ticks by model arthropod-borne RNA viruses in vivo is critical to understanding the virus-host interaction, providing a feasible intervention strategy to control tick-borne arbovirus transmission.