Expression data from human naïve (TN), stem cell memory (TSCM), central memory (TCM) and effector memory (TEM) CD8+ T cells

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.