Rapid Inflammasome Activation Following Mucosal SIV infection of Rhesus Monkeys
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ABSTRACT: The purpose of this study was to evaluated the kinetics of virus dissemination to distal tissues and the initial innate and adaptive host immune responses following intravaginal SIV infection of rhesus monkeys.
Project description:The earliest events following mucosal HIV-1 infection, prior to measurable viremia, remain poorly understood. Here, by detailed necropsy studies, we show that the virus can rapidly disseminate following mucosal SIV infection of rhesus monkeys and trigger components of the inflammasome, both at the site of inoculation and at early sites of distal virus spread. By 24 hr following inoculation, a proinflammatory signature that lacked antiviral restriction factors was observed in viral RNA-positive tissues. The early innate response included expression of NLRX1, which inhibits antiviral responses, and activation of the TGF-? pathway, which negatively regulates adaptive immune responses. These data suggest a model in which the virus triggers specific host mechanisms that suppress the generation of antiviral innate and adaptive immune responses in the first few days of infection, thus facilitating its own replication. These findings have important implications for the development of vaccines and other strategies to prevent infection.
Project description:Cells from SIV-negative (SIVnegative_p17, n=5; SIVnegative_p18, n=5) and SIV-chronic (ChronicSIVinfection_p18, n=6) SP tissues were sorted for microarray studies. RNA samples were prepared using the Illumina beads station assay and hybridized to the Illumina HumanHT-12 version 4 Expression BeadChip according to the Illumina’s instruction. The data were normalized with the quantile normalization method of Bioconductor package limma . Missing values were imputed with R package impute (http://cran.rproject.org/web/packages/impute/index.html). Genes with significant differential expression levels were identified using Bioconductor limma package with >= 1.5 fold change (up or down), the false discovery rate (FDR) adjusted P value < 0.05. Cells from SIV-negative (SIV and SIV-chronic SP) tissues were sorted for micorarray studies
Project description:In this study, we investigated longitudinal changes in response to SIV infection of rhesus monkeys in the presence of morphine, compared to animals administered saline, before and after cART treatment. Using single-cell and single-nucleus RNA sequencing (scRNA-seq and snRNA-seq), we examined the effect of morphine on brain-resident macrophages and microglia in these SIV-infected, cART-suppressed animals to better understand the factors responsible for the morphine-induced increased CNS reservoir and the role of opioids in neuropathogenesis.
Project description:Cells from SIV-negative (SIVnegative_p17, n=5; SIVnegative_p18, n=5) and SIV-chronic (ChronicSIVinfection_p18, n=6) SP tissues were sorted for microarray studies. RNA samples were prepared using the Illumina beads station assay and hybridized to the Illumina HumanHT-12 version 4 Expression BeadChip according to the Illumina’s instruction. The data were normalized with the quantile normalization method of Bioconductor package limma . Missing values were imputed with R package impute (http://cran.rproject.org/web/packages/impute/index.html). Genes with significant differential expression levels were identified using Bioconductor limma package with >= 1.5 fold change (up or down), the false discovery rate (FDR) adjusted P value < 0.05.
Project description:The virus/host interactions during the acute phase of human immunodeficiency virus (HIV) infection help determine the course of disease. During this time period, virus enters the brain. Here, we report clusters of genes whose transcripts are significantly upregulated in the frontal lobe of the brain during acute simian immunodeficiency virus (SIV) infection of rhesus monkeys. Many of these genes are involved in interferon (IFN) and/or interleukin (IL)-6 pathways. Although neither IFNa nor IFN? are elevated in the brain, IL6 is increased. Both IFNa and IL6 are elevated in plasma during this acute phase. The upregulation of STAT1, verified by immunohistochemical staining, can be due to both central nervous system (CNS) (SIV and IL6) and peripheral (IFNa and IL6) causes, and can itself drive the expression of many of these genes. Examination of the levels of expression of the upregulated genes in the post-acute and long-term phases of infection, as well as in SIV encephalitis, reveals increased expression throughout SIV infection, which may serve to protect the brain, but can have untoward long-term consequences.
Project description:Although modern therapies like cART have transformed HIV from a lethal disease to a manageable condition, associated neurocognitive consequences remain a concern. Paradoxically, microglia and macrophages, which comprise the innate defense system in the brain and are crucial for CNS homeostasis, are targets for HIV and key players in its neuropathogenesis. In addition, these infected cells can serve as viral reservoirs even in effectively treated infection. Here using an scRNA-seq approach in the SIV-NHP model, we demonstrate differential transcriptional programs in brain myeloid cells from monkeys under four conditions: uninfected, chronically SIV-infected, chronically SIV-infected treated with combination antiretroviral therapy (cART), and SIVE. Our study reveals alterations in composition (both lineage and gene expression profiles) of the cell populations between groups. Importantly, treatment with cART largely restored the homeostatic microglia profile present in uninfected animals that was disrupted in SIV-infected untreated animals
Project description:Goal of this study was to assess the levels of protection and investigate cellular, humoral, and mucosal immune correlates on the functional and gene transcriptional levels in elite-controller macaques following high dose SIV challenge. Three experimental, post SIV smE660 challenge macaque jejunal samples were individually compared to four pre SIV smE660 challenge baseline samples.
Project description:Salmonella enterica serotype Typhimurium cause a localized enteric infection in immunocompetent patients while human immunodeficiency virus (HIV)-infected patients develop a life threatening bacteremia. We used a rhesus macaque ileal loop model to study how simian immunodeficiency virus (SIV) infection triggers defects in mucosal barrier function that enhance S. Typhimurium dissemination. SIV infection resulted in significant depletion of CD4+ T cells in the intestinal mucosa. Gene expression profiling revealed a defective TH17 response (with suppression of IL-17 and IL-22 expression) and impaired homeostasis of the intestinal epithelium in SIV-infected animals during NTS infection. These findings correlated with an impaired ability of lamina propria CD4+ T cells from SIV-infected macaques to produce IL-17 upon ex vivo stimulation, while production of IFNï§ was not affected. This cytokine imbalance in SIV-infected animals was associated with reduced expression of genes required for intestinal epithelial maintenance and repair, increased fluid secretion during NTS infection, epithelial damage and translocation of a non-invasive S. Typhimurium mutant. Although no defects in neutrophil recruitment were noted, the ileum of SIV-infected animals contained lower levels of the enzyme myeloperoxidase, which may indicate defects in neutrophil killing capacity. S. Typhimurium was recovered in markedly increased numbers from the mesenteric lymph nodes of SIV-infected macaques, illustrating the increased potential for systemic dissemination during co-infection. Our data suggest that SIV-infection causes a multi-factorial defect in mucosal barrier function that promotes bacterial dissemination. Keywords: Disease state analysis Comparison of ileal gene expression profiles in SIV infected rhesus macaques in response to Salmonella challange.
Project description:Question Addressed: How does Simian immunodeficiency virus (SIV) infection alter gene expression in memory CD4 T cell subsets very early during the 1st 10 days after infection? Memory CD4 T cells were sorted from rhesus macaque peripheral blood samples before infection and then at 4 and 10 days post SIV infection. RNA was recovered from the sorted memory CD4 T cells samples. RNA from the time point prior to SIV infection from each individual animal was used as the reference for the post SIV infection time points for that same animal. Thus, for each data set, the 4 and 10 day time points are being directly compared to the pre-infection data from the same animal. RNA samples as indicated above were used for reverse transcription reactions that directly incorporate Cy5 and Cy3 labeled nucleotides into the cDNA. Time: Time after infection with SIV
Project description:Question Addressed: Does gene expression change in the buccal mucosa of Lymphocryptovirus (LCV) infected animals when they are chronically infected with Simian immunodeficiency virus (SIV)? Oropharyngeal mucosal tissue samples were collected from rhesus macaques. A pooled common reference was used for all hybridizations. This reference was composed of RNA harvested from rhesus macaques not infected with either LCV or SIV. Infection: Animals were infected with SIV and/or LCV