Project description:The purpose was to study temporal changes in cellular gene expression upon infection with HIV-1. The T lymphoblastic leukemia cell line SUP-T1 was infected with HIV-1 The purpose was to study temporal changes in cellular gene expression upon infection with HIV-1. 1x10^6 homo sapien were infected with LAI/lab strain at MOI giving infection of almost 100% of cells; this was visible in a QC step in which cells 24 hours after infection were stained for p24 antigen. MOI was set so that this infection rate was achieved after 1 hour incubation of cells with virus. Mock, UV-inactivated virus, and live virus infections were carried out in three (each) separate tubes and infected cells were maintained in separate suspensions (9 samples each). Time point aliquots were then collected in 4-hr intervals from each suspension, cells were pelleted, and lysed in 1 ml Trizol. Lysed samples were immediately frozen on dry ice and moved to -80M-BM-0C until RNA extraction, probe labeling and microarray analysis.
Project description:Our previous work demonstrated that HIV-1 infection progressively reduces TCR/CD3 expression due to a defect in CD3g gene transcripts. We further found that knocking down expression of the viral tat and/or nef genes was correlated with CD3g transcript and TCR/CD3 surface receptor levels on HIV-1 infected cells. This study was undertaken to investigate the direct effect of HIV-1 Tat expression on the TCR/CD3 machinery. Progressive downregulation from TCR/CD3hi to TCR/CD3lo to TCR/CD3? was observed on Tat expressing cells in a manner that emulated HIV-1 infection, with a lack of CD3g transcripts again responsible for the defect. When Tat cell cultures containing a mixture of TCR/CD3 surface densities were separated into TCR/CD3hi and TCR/CD3lo/? populations, they quickly reverted to a mixed CD3 phenotype. Thus, the progression TCR/CD3hi to TCR/CD3lo to TCR/CD3? is an active, reversible process with receptor levels fluctuating in response to intracellular dynamics. Examination of tat mutants found that the regions involved in Tat-mediated transactivation and TAR binding are required for TCR/CD3 downregulation while the lysine at position 28 and Tat exon 2 are dispensable. Global gene expression, assessed in association with TCR/CD3 downregulation in HIV-1 infected and Tat expressing cells, detected broad suppression of TCR/CD3 signaling, co-stimulation and negative regulatory genes along with target transcription factors, ligands and receptors. A significant subset of the genes altered in HIV-1 infected cells was specifically targeted by Tat in association with TCR/CD3 loss. Our finding that Tat negatively regulates many facets of the TCR/CD3 machinery has important implications for disease pathogenesis. This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
Project description:Cell activation is a vital step for T cell memory/effector differentiation as well as for productive HIV infection. To identify novel regulators of this process, we used next generation sequencing to profile changes in microRNA expression occurring in purified human naive CD4 T cells in response to TCR stimulation and HIV infection. HIV infection had no significant impact on global miR expression in quiescent nave CD4 T cells. We identified miR-34c-5p as a novel miR strongly induced by TCR stimulation of nave CD4 T cells, and found that it was consistently down-regulated in response to viral infection. Over-expression of miR-34c-5p had a positive effect on HIV-1 replication. Finally, we demonstrated that miR-34c-5p alters the expression of several genes involved in TCR signaling and cell activation, identifying it as a novel regulator of nave CD4 T cell activation potentially targeted by HIV infection.
Project description:Our previous work demonstrated that HIV-1 infection progressively reduces TCR/CD3 expression due to a defect in CD3g gene transcripts. We further found that knocking down expression of the viral tat and/or nef genes was correlated with CD3g transcript and TCR/CD3 surface receptor levels on HIV-1 infected cells. This study was undertaken to investigate the direct effect of HIV-1 Tat expression on the TCR/CD3 machinery. Progressive downregulation from TCR/CD3hi to TCR/CD3lo to TCR/CD3â was observed on Tat expressing cells in a manner that emulated HIV-1 infection, with a lack of CD3g transcripts again responsible for the defect. When Tat cell cultures containing a mixture of TCR/CD3 surface densities were separated into TCR/CD3hi and TCR/CD3lo/â populations, they quickly reverted to a mixed CD3 phenotype. Thus, the progression TCR/CD3hi to TCR/CD3lo to TCR/CD3â is an active, reversible process with receptor levels fluctuating in response to intracellular dynamics. Examination of tat mutants found that the regions involved in Tat-mediated transactivation and TAR binding are required for TCR/CD3 downregulation while the lysine at position 28 and Tat exon 2 are dispensable. Global gene expression, assessed in association with TCR/CD3 downregulation in HIV-1 infected and Tat expressing cells, detected broad suppression of TCR/CD3 signaling, co-stimulation and negative regulatory genes along with target transcription factors, ligands and receptors. A significant subset of the genes altered in HIV-1 infected cells was specifically targeted by Tat in association with TCR/CD3 loss. Our finding that Tat negatively regulates many facets of the TCR/CD3 machinery has important implications for disease pathogenesis. We used microarrays to investigate changes in CD4+ T cell gene expression induced by expression of the HIV-1 Tat protein. Examine changes in gene expression in HIV-1 Tat transduced cells compared with cells transduced with an antisense Tat sequence used as a control.
Project description:Discovery of novel host-virus interactions leads to a better understanding of mechanisms underlying infection and points to potential therapeutic targets at the interface between virus and host proteins. Recently, global, virus-host interaction networks have been mapped using affinity purification-mass spectrometry (AP-MS) approaches, but these studies do not provide information about dynamic remodeling of host complexes during infection. Here, we describe a novel quantitative proteomics approach in the context of HIV infection to unravel dynamics of the Cullin RING E3 ligase 5 (CRL5) complex, which is hijacked by HIV Vif to degrade the viral restriction factor of the APOBEC3 family. Generating a dynamic and quantitative interaction network of CRL5 under various infection conditions, we identify the E3 ligase ARIH2 as novel regulator of APOBEC3G degradation, which is essential for HIV infectivity in primary CD4+ T-cells. ARIH2 acts in a “tag-team” mechanism that accelerates ubiquitin chain formation on APOBEC3G through CUL5Vif/CBFß by priming the substrate with mono-ubiquitination. Finally, our data suggest a general role for ARIH2 in CRL5 substrate ubiquitination in host cells.
Project description:The lineage relationships and fate of human blood and tissue dendritic cells (DC) has significance for a number of diseases including HIV where both blood and tissue DC may be infected. We used gene expression profiling of monocyte and DC sub-populations sorted directly from blood and skin and compared this to monocyte derived DC (MDDC) and MUTZ3 Langerhans cells (LCs) to define the lineage relationships. Hierarchical clustering analysis showed that plasmacytoid DCs formed the most discrete cluster. The ex vivo derived myeloid cells formed two separate clusters of cells derived from blood, and skin. Separate and specific DC populations could be determined within the sub-clusters. During overnight culture CD14+ dermal DCs (DDC) converted to CD1a+ expressing cells in situ consistent with origin of the CD1a+ DDC from a local precursor rather than from circulating blood DC or monocyte precursors. The in vitro derived MDDC and MUTZ3 populations grouped within the skin DC cluster and MDDCs clustered most closely to CD14+ DDC consistent with the proposed similarity between these two cell types. We identified differential expression of novel genes in particular DC subsets including genes related to DC surface receptors (including C-type lectin receptors, toll-like receptors and galectins). Total RNA was extracted and hybridised to 24 bead arrays. Dendritic cells and monocytes from human blood and skin using magnetic bead and flow cytometry based cell sorting both before and after culture for 24 hours
Project description:Host directed therapies against HIV-1 are thought to be critical for long term containment of the HIV-1 pandemic but remain elusive. Since HIV-1 infects and manipulates important effectors of both the innate and adaptive immune system, identifying modulations of the host cell systems in humans during HIV-1 infection may be crucial for the development of immune based therapies. Here, we quantified the changes of the proteome in human CD4+ T cells upon HIV-1 infection, both in vitro and in vivo. A SWATH-MS approach was used to measure the proteome of human primary CD4+ T cells infected with HIV-1 in vitro as well as CD4+ T cells from HIV-1 infected patients with paired samples on and off antiretroviral treatment. In the in vitro experiment, the proteome of CD4+ T cells was quantified over a time course following HIV-1 infection. 1,725 host cell proteins and 4 HIV-1 proteins were quantified, with 145 proteins changing significantly during the time course. Changes in the proteome peaked 24 hours after infection, concomitantly with significant HIV-1 protein production. In the in vivo branch of the study, CD4+ T cells from viremic patients and those with no detectable viral load after treatment were sorted and the proteomes quantified. We consistently detected 895 proteins, 172 of which were considered to be significantly different between viraemic patients and patients undergoing successful treatment. The proteome of in vitro infected CD4+ T cells was modulated on multiple functional levels, including TLR-4 signalling and the type 1 interferon signalling pathway. Perturbations in the type 1 interferon signalling pathway were recapitulated in CD4+ T cells from patients. The study shows that proteome maps generated by SWATH-MS indicate a range of functionally significant changes in the proteome of HIV infected human CD4+ T cells. Exploring these perturbations in more detail may help identify new targets for immune based interventions.
Project description:To examine the gene expression data in retinal punches from posterior poles in HIV positive (PP+) and HIV negative (PP-) autopsy eyes we used a microarray approach with the HumanHT-12 v4 Expression BeadChip
Project description:The lineage relationships and fate of human blood and tissue dendritic cells (DC) has significance for a number of diseases including HIV where both blood and tissue DC may be infected. We used gene expression profiling of monocyte and DC sub-populations sorted directly from blood and skin and compared this to monocyte derived DC (MDDC) and MUTZ3 Langerhans cells (LCs) to define the lineage relationships. Hierarchical clustering analysis showed that plasmacytoid DCs formed the most discrete cluster. The ex vivo derived myeloid cells formed two separate clusters of cells derived from blood, and skin. Separate and specific DC populations could be determined within the sub-clusters. During overnight culture CD14+ dermal DCs (DDC) converted to CD1a+ expressing cells in situ consistent with origin of the CD1a+ DDC from a local precursor rather than from circulating blood DC or monocyte precursors. The in vitro derived MDDC and MUTZ3 populations grouped within the skin DC cluster and MDDCs clustered most closely to CD14+ DDC consistent with the proposed similarity between these two cell types. We identified differential expression of novel genes in particular DC subsets including genes related to DC surface receptors (including C-type lectin receptors, toll-like receptors and galectins). Total RNA was extracted and hybridised to 62 cDNA arrays. Dendritic cells and monocytes from human blood and skin using magnetic bead and flow cytometry based cell sorting both before and after culture for 24 hours
Project description:In this study, treatment-naive HIV, HCV mono-/co-infected individuals with CD4+ T cell counts >300/?l were recruited and their global gene expression profiles were investigated. By gene set enrichment analysis (GSEA), we revealed that gene sets of cell cycle progression, innate immune response and some transcription factors in CD4+ T cells were affected mainly by HIV; while genes associated with extracellular matrix (ECM), Beta cell development and insulin synthesis and secretion were the major targets of HCV. For metabolic pathways, it was modulated by both viruses. Besides, for the first time, our data uncovered the importance of GPCR signaling pathway during HCV, HIV infections. These data for the first time offer genetic basis for HCV/HIV mono-/co- infections, which will facilitate the understanding of the interaction of HCV/HIV in vivo and how they subvert the human gene machinery at the individual cell type level.