title: Phenotypic and functional analysis of immune CD8+ T cell responses induced by a single injection of a HIV DNA vaccine in mice.
abstract: HIV DNA vaccines are potent inducers of cell-mediated immune (CMI) response in mice but elicit poor HIV-specific IFN-gamma-producing T cells in monkeys and humans. In this study, we performed kinetic analyses on splenocytes of BALB/c mice that were immunized by a single injection with a unique DNA vaccine. Using IFN-gamma-ELISPOT and multiparametric FACS analysis, we characterized the induced CMI response. We found that the response was detectable for at least 63 wk. ELISPOT detection of IFN-gamma-producing T cells showed a profile with two waves separated by a long period of minimal response. Multiparametric FACS analysis showed two populations of CD3(+)CD8(+) T cells that were specific for all HIV Ags. These cells had similar robust proliferation abilities and contained granzyme B. However, only a few produced IFN-gamma. Both IFN-gamma-producing and non-IFN-gamma-producing HIV-specific CD8(+) T cells were detected in the early stage (week (W)1 and W2 postimmunization (PI)), in the prolonged intermediate period of minimal response (W4-W26 PI), and in the final late phase of increased response (W30-W63 PI). Our longitudinal characterization showed that both subsets of cells underwent expansion, contraction, and memory generation/maintenance phases throughout the lifespan of the animal. Altogether, these findings bring insight to the heterogeneity of the immune T cell response induced by a single immunization with this DNA and strengthen the concept that used of the IFN-gamma-ELISPOT assay alone may be insufficient to detect critical T cell responses to candidate HIV vaccines.
authors.affiliation: Department of Microbiology, Molecular Genetics, and Immunology, University of Kansas Medical Center, Kansas City, KS 66160, USA. garrode@kumc.edu
authors.forename: Geraldine
authors.initials: G
authors.lastname: Arrode
authors.forename: Ramakrishna
authors.initials: R
authors.lastname: Hegde
authors.forename: Arunmani
authors.initials: A
authors.lastname: Mani
authors.forename: Yuhuai
authors.initials: Y
authors.lastname: Jin
authors.forename: Yahia
authors.initials: Y
authors.lastname: Chebloune
authors.forename: Opendra
authors.initials: O
authors.lastname: Narayan
mesh_terms: D016915:AIDS Vaccines / Q000276:immunology* / Q000494:pharmacology; D000818:Animals; D017252:CD3 Complex / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D053804:Granzymes / Q000276:immunology; D015488:HIV Antigens / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology* / Q000517:prevention & control; D000882:Haplorhini; D006801:Humans; D007114:Immunization; D007156:Immunologic Memory / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D013045:Species Specificity; D019444:Vaccines, DNA / Q000276:immunology* / Q000494:pharmacology
chemical_list: D016915:AIDS Vaccines; D017252:CD3 Complex; D015488:HIV Antigens; D019444:Vaccines, DNA; D007371:Interferon-gamma; D053804:Granzymes