title: Rectification of age-associated deficiency in cytotoxic T cell response to influenza A virus by immunization with immune complexes.
abstract: Decline in cellular immunity in aging compromises protection against infectious diseases and leads to the increased susceptibility of the elderly to infection. In particular, Ag-specific cytotoxic T lymphocyte (CTL) response against virus is markedly reduced in an aged immune system. It is of great importance to explore novel strategy in eliciting effective antiviral CTL activity in the elderly. In this study, the efficacy and mechanisms of immunization with immune complexes in overcoming age-associated deficiency in cellular immunity were investigated. In this study, we show that the severely depressed CTL response to influenza A in aged mice can be significantly restored by immunization with immune complexes consisting of influenza A virus and mAb to influenza A nucleoprotein. The main mechanisms underlying this recovery of CTL response induced by immune complex immunization in aged mice are enhanced dendritic cell function and elevated production of IFN-gamma in both CD4(+) Th1 and CD8(+) CTLs. Thus, these results demonstrate that immune complex immunization may represent a novel strategy to elicit effective virus-specific cytotoxic response in an aged immune system, and possibly, to overcome age-related immune deficiency in general.
authors.affiliation: Department of Immunology, Baylor College of Medicine, Houston, Texas 77030, USA.
authors.forename: Biao
authors.initials: B
authors.lastname: Zheng
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Hongxia
authors.initials: H
authors.lastname: He
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Marinova
authors.forename: Kirsten
authors.initials: K
authors.lastname: Switzer
authors.forename: Daniel
authors.initials: D
authors.lastname: Wansley
authors.forename: Innocent
authors.initials: I
authors.lastname: Mbawuike
authors.forename: Shuhua
authors.initials: S
authors.lastname: Han
mesh_terms: D000375:Aging / Q000276:immunology*; D000818:Animals; D000936:Antigen-Antibody Complex / Q000276:immunology*; D002454:Cell Differentiation / Q000276:immunology; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology; D006388:Hemagglutinins / Q000276:immunology; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007252:Influenza Vaccines / Q000276:immunology*; D007371:Interferon-gamma / Q000096:biosynthesis; D051379:Mice; D008807:Mice, Inbred BALB C; D009698:Nucleoproteins / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D000936:Antigen-Antibody Complex; D006388:Hemagglutinins; D007252:Influenza Vaccines; D009698:Nucleoproteins; D007371:Interferon-gamma