title: Analysis of the frequencies and of the memory T cell phenotypes of human CD8+ T cells specific for influenza A viruses.
abstract: We characterized the human CD8+ T cell response against influenza A viruses by a flow cytometry-based assay. Peripheral blood mononuclear cells (PBMCs) were incubated with inactivated influenza virus preparation, for 17 h, and were stained for intracellular interferon-gamma. Major histocompatibility complex class I-restricted memory CD8+ T cells specific for influenza antigens were detected in PBMCs from all 19 adult donors, at an average frequency of 0.39%. On average, 83% of influenza virus-specific CD8+ T cells expressed the differentiation-associated marker CD27, a percentage that is significantly higher than that of CD8+ T cells specific for pp65 of human cytomegalovirus (53%). These observations indicate that class I-restricted immunity against influenza A viruses is characterized by the persistence, after clearance of infection, of circulating antigen-specific CD8+ T cells. The different patterns of CD27 expression in influenza virus- and cytomegalovirus-specific CD8+ T cells suggest that influenza virus-specific memory and effector CD8+ T cells can be differentiated by phenotypic analysis.
authors.affiliation: Stanford University School of Medicine, Stanford, California, USA. xiaosong@stanford.edu
authors.forename: Xiao-Song
authors.initials: XS
authors.lastname: He
authors.forename: Kutubuddin
authors.initials: K
authors.lastname: Mahmood
authors.forename: Holden T
authors.initials: HT
authors.lastname: Maecker
authors.forename: Tyson H
authors.initials: TH
authors.lastname: Holmes
authors.forename: George W
authors.initials: GW
authors.lastname: Kemble
authors.forename: Ann M
authors.initials: AM
authors.lastname: Arvin
authors.forename: Harry B
authors.initials: HB
authors.lastname: Greenberg
mesh_terms: D000328:Adult; D000956:Antigens, Viral / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D002455:Cell Division; D005260:Female; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D006801:Humans; D007156:Immunologic Memory; D009980:Influenza A virus / Q000276:immunology*; D007371:Interferon-gamma / Q000378:metabolism; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000276:immunology / Q000378:metabolism
chemical_list: D000956:Antigens, Viral; D015395:Histocompatibility Antigens Class I; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7; D007371:Interferon-gamma