Project description:We used microarrays to compare the global programme of gene expression in HTLV-positive, ATL-derived and HTLV-positive in vitro-transformed cell lines with that of uninfected primary CD4 T cells.
Project description:We used microarrays to compare the global programme of gene expression in HTLV-positive, ATL-derived and HTLV-positive in vitro-transformed cell lines with that of uninfected primary CD4 T cells. Cells were harvested one day after splitting, in case of primary T cells, cells were harvested after reaching a postmitotic state.
Project description:Human T-cell leukemia virus type 1 (HTLV-1) is linked to the development of adult T-cell leukemia (ATL) and the neuroinflammatory disease, HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The HTLV-1 Tax oncoprotein regulates viral gene expression and the NF-kB pathway to promote the survival of HTLV-1 infected T cells. In thsi study, we utilize a kinome-wide shRNA screen to identify the tyrosine kinase KDR/VEGFR2 as an essential survival factor of HTLV-1-transformed T cells. Inhibition of KDR induces apoptosis of Tax expressing HTLV-1-transformed cell lines and CD4+ T cells from HAM/TSP patients. Phosphoproteomics analysis of HTLV-1 transformed cells treated with a KDR inhibitor revealed inhibition of the phosphorylation of multiple receptors/cell surface proteins, ubiquitin conjugating systems, proteases, phosphatases, apoptotic regulatory factors, adhesion/extracellular matrix proteins and viral proteins. This work suggests that HTLV-1 Tax has hijacked KDR kinase activity to promote Tax stability and the proliferation and survival of HTLV-1 infected cells.
Project description:Human T-cell leukemia virus type 1 (HTLV-1) bZIP factor (HBZ) which is encoded in the minus strand of HTLV-1 provirus, possesses dual function as protein, and also as RNA. To know the effect of HBZ RNA and protein in primary T-cells, we introduced HBZ, or its mutant TTG (exclude protein activity), or SM (exclude RNA activity) with retrovirus vector into CD4 positive murine T cells, and analysed the transcriptome profiling. We found that HBZ RNA altered cell cycle progression, cell survival related genes, while HBZ protein altered immunology related genes. This microarray results demonstrated that HBZ RNA and protein possess distinct functions in primary cells. CD4 positive cells were enriched from murine splenocyte, and cultured with irradiated antigen presenting cells (APC). HBZ, or its mutant were introduced with retroviral vector. Forty eight hours after introduction, cells were washed and cultured with recombinant human IL-2. Further 48 hours after culture, virus infected cells were sorted and analysed by agilent microarray.
Project description:Human T-cell leukemia virus type 1 (HTLV-1) bZIP factor (HBZ) which is encoded in the minus strand of HTLV-1 provirus, possesses dual function as protein, and also as RNA. To know the effect of HBZ RNA and protein in primary T-cells, we introduced HBZ, or its mutant TTG (exclude protein activity), or SM (exclude RNA activity) with retrovirus vector into CD4 positive murine T cells, and analysed the transcriptome profiling. We found that HBZ RNA altered cell cycle progression, cell survival related genes, while HBZ protein altered immunology related genes. This microarray results demonstrated that HBZ RNA and protein possess distinct functions in primary cells.
Project description:Infections by Human T cell Leukaemia Virus type 1 (HTLV-1) persist for the lifetime of the host by integrating into the genome of CD4+ T cells. Proviral gene expression is core to proviral survival and the maintenance of the proviral load, through the pro-proliferative changes it induces in infected cells. Despite their role in HTLV-1 infection and a persistent cytotoxic T lymphocyte response raised against them, proviral transcripts from the sense-strand are rarely detected in fresh cells extracted from the peripheral blood, and have recently been found to be expressed intermittently by a small subset of cells at a given time. Ex vivo culture of infected cells prompts synchronised proviral expression in infected cells from peripheral blood, allowing the study of factors involved in reactivation in primary cells. Here, we used bulk RNA-seq to examine the host transcriptome over six days in vitro, following proviral reactivation in primary peripheral CD4+ T cells isolated from subjects with non-malignant HTLV-1 infection. Infected cells displayed a conserved response to reactivation, characterised by discrete stages of gene expression, cell division and subsequently horizontal transmission of the virus. We observed widespread changes in Polycomb gene expression following reactivation, including an increase in PRC2 transcript levels and diverse changes in the expression of PRC1 components. We hypothesize that these transcriptional changes constitute a negative feedback loop that maintains proviral latency by re-deposition of H2AK119ub1 following the end of proviral expression. Using RNAi, we found that certain deubiquitinases, BAP1, USP14 and OTUD5 each promote proviral transcription. These data demonstrate the detailed trajectory of HTLV-1 proviral reactivation in primary HTLV-1-carrier lymphocytes and the impact on the host cell.
Project description:To address whether changes in miRNA expression accompany cell-associated replication of HTLV-1 in vivo, we carried out the miRNA expression profiling of CD4+ and CD8+ T-cells derived from naturally HTLV-1 infected individuals with no clinical sign of malignancy. T-cell clones were obtained by limiting dilution culture of PBMCs of HTLV-1 carriers. miRNA expression was assessed by Agilent V3 miRNA array according to the manufacturer's instructions. miRNA expression profiles of cloned CD4+ and CD8+ T-cells (carrying or not HTLV-1) derived from naturally HTLV-1 infected individuals.
Project description:HTLV-1 preferentially infects CD4+ T cells and these cells play a central role in HTLV-1 infection. In this study, we investigated the global gene expression profile of circulating CD4+ T cells from distinct clinical status of HTLV-1-infected individuals in regard to Tax expression levels. CD4+ T cells were isolated from asymptomatic HTLV-1 carrier (HAC) and HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) patients, in order to identify genes involved in the HAM/TSP development. Hierarchical clustering analysis showed that healthy controls (CT) and HTLV-1-infected samples clustered separately. We also observed that HAC and HAM/TSP groups clustered separately regardless Tax expression. The gene expression profile of CD4+ T cells was compared among CT, HAC and HAM/TSP groups. The IL-27, PXN, CXCR4, GZMA, PRF1 and Foxp3 genes were differentially expressed between HAC and HAM/TSP groups and the frequency of CD4+Foxp3+ regulatory T cells (Treg) were higher in HTLV-1-infected individuals. These findings suggest that CD4+ T cells activity is distinct between HAC and HAM/TSP groups as expected. In order to study the transcriptional changes in CD4 T cell from HTLV-1-infected individuals, immunomagnetically purified CD4+ T-cells from the peripheral blood of 4 asymptomatic HTLV-1 carrier individuals (HAC) and 4 individuals with HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP), as well as from 4 healthy controls (CT) were isolated and processed the microarray assay according Agilent's protocol. The differential expressed genes, molecular characterization and networks analysis were evaluated using robust bioinformatic tools, then the real time PCR was done to validate the genes.