title: Evidence for intact costimulation via CD28 and CD27 molecules in hyporesponsive T cells from human immunodeficiency virus-infected individuals.
abstract: In the activation of T cells, the primary signal is antigen-specific and given through T cell receptor (TcR)/CD3 ligation. Furthermore, costimulatory molecules such as CD28 and CD27, provide an essential signal for activation through interaction with their ligands, present on the membrane of antigen-presenting cells. During asymptomatic human immunodeficiency virus (HIV)-1 infection, T cell function is progressively lost. Here, we investigated whether in the presence of impaired responses of T cells from HIV-infected individuals to signal one, costimulation through CD28 and CD27 after interaction with their natural ligands CD80 and CD70 is intact. T cell proliferative responses to signal one in combination with CD80 or CD70 were decreased in a large fraction of asymptomatically HIV-infected individuals. This was due to impaired responses of signal one but not to impaired responses to costimulation, since CD80 or CD70 did enhance signal one-mediated proliferative responses to a normal extent. Moreover, in individuals with proliferative responses to signal one that were decreased to 50% of normal T cell responses, costimulation even was increased compared to controls. Our results demonstrate that in HIV-infected individuals the response to costimulation is relatively preserved compared to responses to the first signal and point to the defect in T cells in HIV infection being primarily in the CD3/TcR-mediated pathway.
authors.affiliation: Department of Clinical Viro-Immunology, Central Laboratory of The Netherlands Red Cross Blood Transfusion Service, Amsterdam.
authors.forename: L
authors.initials: L
authors.lastname: Meyaard
authors.forename: H
authors.initials: H
authors.lastname: Kuiper
authors.forename: S A
authors.initials: SA
authors.lastname: Otto
authors.forename: K C
authors.initials: KC
authors.lastname: Wolthers
authors.forename: R A
authors.initials: RA
authors.lastname: van Lier
authors.forename: F
authors.initials: F
authors.lastname: Miedema
mesh_terms: D015703:Antigens, CD / Q000276:immunology*; D018122:B7-1 Antigen / Q000276:immunology; D018801:CD2 Antigens / Q000276:immunology; D053282:CD27 Ligand; D018106:CD28 Antigens / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D015658:HIV Infections / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D008565:Membrane Proteins / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D015398:Signal Transduction / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7 / Q000276:immunology
chemical_list: D015703:Antigens, CD; D018122:B7-1 Antigen; D018801:CD2 Antigens; D053282:CD27 Ligand; D018106:CD28 Antigens; D017252:CD3 Complex; C505771:CD70 protein, human; D008565:Membrane Proteins; D011948:Receptors, Antigen, T-Cell; D018127:Tumor Necrosis Factor Receptor Superfamily, Member 7