Peripheral blood-derived virus-specific memory stem T cells mature to functional effector memory subsets with self-renewal potency

Memory T cells expressing stem cell–like properties have been described recently. The capacity of self-renewal and differentiation into various memory/effector subsets make them attractive for adoptive T cell therapy to combat severe virus infections and tumors. The very few reports on human memory stem T cells (TSCM) are restricted to analyses on polyclonal T cells, but extensive data on Ag-specific TSCM are missing. This might be due to their very low frequency limiting their enrichment and characterization. In this article, we provide functional and phenotypic data on human viral-specific TSCM, defined as CD8+CD45RA+CCR7+CD127+CD95+. Whereas