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PubMed · 9294140

Rapid effector function in CD8+ memory T cells.

A Lalvani·R Brookes·S Hambleton·W J Britton·A V Hill·A J McMichael
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Abstract

The nature of the CD8+ T cells that underlie antiviral protective immunological memory in vivo is unclear. We have characterized peptide-specific CD8+ T lymphocytes directly ex vivo from peripheral blood in humans with past exposure to influenza virus, using single cell interferon gamma (IFN-gamma) release as a measure of effector function. In individuals in the memory state with respect to influenza virus infection, unrestimulated antigen-specific CD8+ T cells displayed IFN-gamma release within 6 h of antigen contact, identifying a population of memory CD8+ T cells that exhibit effector function without needing to divide and differentiate over several days. We have quantified circulating CD8+ effector T cells specific for six different MHC class I-restricted influenza virus epitopes. Enumeration of these CD8+ T cells gives frequencies of peptide-specific T cells that correlate with, but are in general severalfold higher than, CTL precursor frequencies derived from limiting dilution analysis, indicating that this novel population of memory CD8+ T cells has hitherto been undetected by standard means. The phenotype of these cells, which persist at a low frequency long after recovery from an acute viral infection, suggests that they play a role in protective immunological memory.

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AdultAmino Acid SequenceAntigens, ViralCD8-Positive T-LymphocytesEpitopesHLA AntigensHistocompatibility Antigens Class IHumansImmunologic MemoryIn Vitro TechniquesInfluenza, HumanInterferon-gammaOrthomyxoviridaePhenotypeReceptors, Antigen, T-Cell, alpha-betaT-Lymphocytes, CytotoxicJournal ArticleResearch Support, Non-U.S. Gov't

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A Lalvani, R Brookes, S Hambleton, W J Britton, A V Hill, A J McMichael. 1997-09-15. Rapid effector function in CD8+ memory T cells.. https://doi.org/10.1084/jem.186.6.859

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