title: Phenotypic, functional, and kinetic parameters associated with apparent T-cell control of human immunodeficiency virus replication in individuals with and without antiretroviral treatment.
abstract: The human immunodeficiency virus (HIV)-mediated immune response may be beneficial or harmful, depending on the balance between expansion of HIV-specific T cells and the level of generalized immune activation. The current study utilizes multicolor cytokine flow cytometry to study HIV-specific T cells and T-cell activation in 179 chronically infected individuals at various stages of HIV disease, including those with low-level viremia in the absence of therapy ("controllers"), low-level drug-resistant viremia in the presence of therapy (partial controllers on antiretroviral therapy [PCAT]), and high-level viremia ("noncontrollers"). Compared to noncontrollers, controllers exhibited higher frequencies of HIV-specific interleukin-2-positive gamma interferon-positive (IL-2(+) IFN-gamma(+)) CD4(+) T cells. The presence of HIV-specific CD4(+) IL-2(+) T cells was associated with low levels of proliferating T cells within the less-differentiated T-cell subpopulations (defined by CD45RA, CCR7, CD27, and CD28). Despite prior history of progressive disease, PCAT patients exhibited many immunologic characteristics seen in controllers, including high frequencies of IL-2(+) IFN-gamma(+) CD4(+) T cells. Measures of immune activation were lower in all CD8(+) T-cell subsets in controllers and PCAT compared to noncontrollers. Thus, control of HIV replication is associated with high levels of HIV-specific IL-2(+) and IFN-gamma(+) CD4(+) T cells and low levels of T-cell activation. This immunologic state is one where the host responds to HIV by expanding but not exhausting HIV-specific T cells while maintaining a relatively quiescent immune system. Despite a history of advanced HIV disease, a subset of individuals with multidrug-resistant HIV exhibit an immunologic profile comparable to that of controllers, suggesting that functional immunity can be reconstituted with partially suppressive highly active antiretroviral therapy.
authors.affiliation: Department of Medicine, San Francisco General Hospital, University of California, 94110, USA.
authors.forename: Brinda
authors.initials: B
authors.lastname: Emu
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Sinclair
authors.forename: David
authors.initials: D
authors.lastname: Favre
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Moretto
authors.forename: Priscilla
authors.initials: P
authors.lastname: Hsue
authors.forename: Rebecca
authors.initials: R
authors.lastname: Hoh
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Martin
authors.forename: Douglas F
authors.initials: DF
authors.lastname: Nixon
authors.forename: Joseph M
authors.initials: JM
authors.lastname: McCune
authors.forename: Steven G
authors.initials: SG
authors.lastname: Deeks
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D015703:Antigens, CD / Q000276:immunology; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D006678:HIV / Q000276:immunology*; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology; D007700:Kinetics; D008213:Lymphocyte Activation; D010641:Phenotype; D012367:RNA, Viral / Q000097:blood / Q000302:isolation & purification; D013601:T-Lymphocytes / Q000276:immunology*; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents; D015703:Antigens, CD; D007376:Interleukin-2; D012367:RNA, Viral; D007371:Interferon-gamma