title: Cytotoxic T lymphocyte responses to a liposome-adjuvanted influenza A virus vaccine in the elderly.
abstract: This randomized double-blind study evaluated cytotoxic T lymphocyte (CTL) responses of elderly volunteers after parenteral immunization with either liposome-adjuvanted (n = 23) or control subvirion (n = 26) vaccine containing detergent-split influenza A/Taiwan/1/86 (H1N1) virus. Peripheral blood mononuclear cells obtained 0, 2, and 12 weeks after vaccination were stimulated in vitro with influenza A (H1N1) virus-infected autologous cells and then assayed for influenza virus-specific cytotoxicity using autologous virus-infected target cells. CTL responses to vaccination exhibited influenza A virus heterosubtypic cross-reactivity and were mediated primarily by CD8+ effector cells. Anti-influenza virus CTL activity was enhanced to a significantly greater extent by the liposome vaccine than by the control subvirion vaccine. It remains to be established whether the advantage of a liposomal formulation in terms of an improved CTL response is relevant to vaccine protective efficacy.
authors.affiliation: Geriatric Research, Education and Clinical Center, St. Louis VA Medical Center, Missouri, USA.
authors.forename: D C
authors.initials: DC
authors.lastname: Powers
authors.forename: M C
authors.initials: MC
authors.lastname: Manning
authors.forename: P J
authors.initials: PJ
authors.lastname: Hanscome
authors.forename: P J
authors.initials: PJ
authors.lastname: Pietrobon
mesh_terms: D000276:Adjuvants, Immunologic; D000368:Aged; D000369:Aged, 80 and over; D004304:Dosage Forms; D004311:Double-Blind Method; D006801:Humans; D009980:Influenza A virus / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control*; D008081:Liposomes; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D013997:Time Factors
chemical_list: D000276:Adjuvants, Immunologic; D004304:Dosage Forms; D007252:Influenza Vaccines; D008081:Liposomes