Project description:The development of T cells has been characterized as taking place over three stages: naïve (Tn), central memory (Tcm), and effector memory (Tem) cells. Recently, stem cell memory T cells (Tscm) were found to be the least-developed memory subset. We performed detailed analysis of the gene expression of human CD4+ T cells with clear distinction of the Tn, Tscm, Tcm, and Tem stages. We sorted Tn, Tscm, Tcm, and Tem CD4+ T cells from the peripheral blood of six healthy volunteers to see the differences of gene expression between each developmental stage.
Project description:The development of T cells has been characterized as taking place over three stages: naïve (Tn), central memory (Tcm), and effector memory (Tem) cells. Recently, stem cell memory T cells (Tscm) were found to be the least-developed memory subset. We performed detailed analysis of the gene expression of human CD4+ T cells with clear distinction of the Tn, Tscm, Tcm, and Tem stages.
Project description:The development of T cells has been characterized as taking place over three stages: naïve (Tn), central memory (Tcm), and effector memory (Tem) cells. Recently, stem cell memory T cells (Tscm) were found to be the least-developed memory subset. We performed detailed analysis of the gene expression of human CD4+ T cells from patients with rheumatoid arthritis with clear distinction of the Tn, Tscm, Tcm, and Tem stages.
Project description:Stem cell memory T cells can be defined as the memory T cell subsets with naïve T cell phenotypes and stem cell-like properties. We find that Notch signaling converts activated T cells into stem cell memory T (TSCM) cells by OP9-DL1 feeder cell coculture. Based on gene expression profile analysis, we provide evidence that these cells represent distinct characters with central memory T (TCM) cells and naïve T cells with effector molecules and transcription factors. TSCM cells induced by Notch cluster closer to TCM cells than naïve T cells, and display similar phenotypes to TCM phenotype in terms of effector molecules and transcription factors, but the gene expressions of TSCM cells are entirely lower than that of TCM cells.
Project description:We assessed correlates of protection from disease progression in a rare subset of HIV-infected individuals, viremic non-progressors (VNPs). These individuals have high viral load for several years, but in contrast to the majority of infected individuals, they do not progress to AIDS. Here we found this lack of progression was associated with selective preservation of two essential subsets of memory CD4+ T cells, central memory (TCM) and stem-cell memory (TSCM) cells. Compared to HIV-infected putative progressors, VNPs had higher proliferation of these indispensable subsets of memory cells, which was associated with the number of TCM. In addition, the long-lived CD4+ TCM and TSCM cells in VNPs had decreased HIV infection compared to the less critical effector memory CD4+ T cells, which indicates a possible mechanism by which VNPs maintain their CD4+ T cell pool after several years of infection, and remain free from AIDS progression.
Project description:An early-differentiated CD8+ memory T cell subset with stem cell-like properties (TSCM) can be identified within the naïve-like T cell population by the expression of CD95/Fas. Based on experiments including exon- and gene-level expression analysis, we provide evidence that this subset of antigen-specific cells represents an early precursor of conventional central (TCM) and effector (TEM) memory CD8+ T cells with enhanced self-renewal capacity and proliferative potential. We identified 900 genes differentially expressed between major T cell subsets defined along with memory T cell commitment. Based on the analysis of these genes, CD95+ naïve T cells (TSCM) cluster closer to the CD8+ T memory compartment than to classical (CD95-) naïve T (TN) cells, and display an intermittent phenotype between classical TN and TCM cells in terms of all major T cell differentiation markers analyzed. Three healthy human blood donors provided lymphocyte-enriched apheresis blood for this study after informed consent. From all samples, total RNA was isolated using an RNEasy Micro kit (Qiagen), processed by Ambion’s WT expression kit, fragmented and labeled with a WT Terminal Labeling Kit (Affymetrix), hybridized to WT Human Gene 1.0 ST arrays (Affymetrix) and stained on a Genechip Fluidics Station 450 (Affymetrix), all according to the respective manufacturer's instructions. Samples represent "exon-level" and "gene-level" analyses.
Project description:An early-differentiated CD8+ memory T cell subset with stem cell-like properties (TSCM) can be identified within the naïve-like T cell population by the expression of CD95/Fas. Based on experiments including exon- and gene-level expression analysis, we provide evidence that this subset of antigen-specific cells represents an early precursor of conventional central (TCM) and effector (TEM) memory CD8+ T cells with enhanced self-renewal capacity and proliferative potential. We identified 900 genes differentially expressed between major T cell subsets defined along with memory T cell commitment. Based on the analysis of these genes, CD95+ naïve T cells (TSCM) cluster closer to the CD8+ T memory compartment than to classical (CD95-) naïve T (TN) cells, and display an intermittent phenotype between classical TN and TCM cells in terms of all major T cell differentiation markers analyzed.
Project description:We assessed correlates of protection from disease progression in a rare subset of HIV-infected individuals, viremic non-progressors (VNPs). These individuals have high viral load for several years, but in contrast to the majority of infected individuals, they do not progress to AIDS. Here we found this lack of progression was associated with selective preservation of two essential subsets of memory CD4+ T cells, central memory (TCM) and stem-cell memory (TSCM) cells. Compared to HIV-infected putative progressors, VNPs had higher proliferation of these indispensable subsets of memory cells, which was associated with the number of TCM. In addition, the long-lived CD4+ TCM and TSCM cells in VNPs had decreased HIV infection compared to the less critical effector memory CD4+ T cells, which indicates a possible mechanism by which VNPs maintain their CD4+ T cell pool after several years of infection, and remain free from AIDS progression. 6 HIV-infected patients fitting the clinical criteria of Viremic Non-Progressors were identified. VNPs were defined as having confirmed HIV-1 infection for at least 9 years with sustained plasma HIV RNA levels >10,000 copies/ml and maintenance of peripheral blood CD4+ T cell counts >500 cells/mm3 and a CD4% (of all lymphocytes) >15%. As controls, 7 HIV-infected Putative Progressors were identified. PPs were defined as having plasma HIV RNA levels >10,000 copies/mL, CD4+ T cell counts >400 cells/mm3 and having been initially infected with HIV 2-24 months prior to the index visit. The estimated date of initial HIV infection was calculated according to published algorithms that incorporate âde-tunedâ anti-HIV-1 antibody ELISA results or by a documented sero-conversion window of <6 months. All participants were required to be antiretroviral therapy (ART)-naïve. RNA from 6 VNP and 7 PPs was purified from PAXgene whole blood tubes and hybridized to Affymetrix U133 Plus 2.0 arrays. During data analysis, one VNP patient (PID 4015) was determined to be an outlier and removed from further analysis. Thus, 5 VNPs and 7 PPs are represented in this Series.
Project description:Memory T cells are heterogeneous in terms of their phenotype and functional properties. We investigated the molecular profiles of human CD8 naïve (TN), central memory (TCM), effector memory (TEM), and effector memory RA (TEMRA) T cells using gene expression microarrays and phospho-protein-specific intracellular flow cytometry. We demonstrate that TCM have a gene expression and cytokine signaling signature that lies between that of TN and TEM or TEMRA cells, whereas TEM and TEMRA are closely related. Our data define the molecular basis for the different functional properties of central and effector memory subsets. We show that TEM and TEMRA cells strongly express genes with known importance in CD8 T cell effector function. In contrast, TCM are characterized by high basal and cytokine-induced STAT5 phosphorylation, reflecting their capacity for self-renewal. Altogether, our results distinguish TCM and TEM/TEMRA at the molecular level and are consistent with the concept that TCM represent memory stem cells.