title: Changes in HIV-specific antibody responses and neutralization titers in patients under ART.
abstract: In this study, we tested for antibody reactivities against gp120 and gp41-derived peptides, recombinant gp160, gp41 and tat in HIV-positive sera under antiretroviral therapy (ART) and determined their neutralization capacity. As a baseline, sera from patients in stage A, B and C of the disease, long term non-progressors (LNPs) and HIV-negative individuals were included. Compared to LNPs or sera from patients in group A, the reactivity of sera in stage B or C against gp120-derived peptides was reduced parallel to disease progression. Reactivity of these samples was compared with sera of patients under ART. Parallel to the decrease of viral load, the reactivity against gp120 and gp41-derived epitopes, recombinant gp160 and gp41 or the native gp120/41 complex was significantly reduced. Antibody-mediated neutralization of HIV-1 was detectable prior to ART but revealed substantial decreases coupled with progression of therapy. Responses to recombinant tat dropped after three months of therapy, increased however at later time points to initial levels. These data indicate that in parallel to the decrease in viral load and antibodies against gp120, the neutralization capacity of sera under ART is reduced, and can not be compensated by an increase in tat-specific antibodies.
authors.affiliation: Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University and L. Boltzmann-Institute of AIDS Research, Fritz Pregl Str. 3, 6020 Innsbruck, Austria. Barbara.Falkensammer@i-med.ac.at
authors.forename: Barbara
authors.initials: B
authors.lastname: Falkensammer
authors.forename: Doris
authors.initials: D
authors.lastname: Freissmuth
authors.forename: Luzia
authors.initials: L
authors.lastname: Hübner
authors.forename: Cornelia
authors.initials: C
authors.lastname: Speth
authors.forename: Manfred Paul
authors.initials: MP
authors.lastname: Dierich
authors.forename: Heribert
authors.initials: H
authors.lastname: Stoiber
mesh_terms: D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology*; D015696:Gene Products, tat / Q000276:immunology; D015488:HIV Antigens / Q000276:immunology*; D015699:HIV Envelope Protein gp120 / Q000276:immunology; D019302:HIV Envelope Protein gp160 / Q000276:immunology; D015700:HIV Envelope Protein gp41 / Q000276:immunology; D015658:HIV Infections / Q000188:drug therapy / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D009500:Neutralization Tests; D010455:Peptides / Q000276:immunology; D014759:Viral Envelope Proteins / Q000276:immunology*; D054322:tat Gene Products, Human Immunodeficiency Virus
chemical_list: D000914:Antibodies, Viral; D015696:Gene Products, tat; D015488:HIV Antigens; D015699:HIV Envelope Protein gp120; D019302:HIV Envelope Protein gp160; D015700:HIV Envelope Protein gp41; D010455:Peptides; D014759:Viral Envelope Proteins; D054322:tat Gene Products, Human Immunodeficiency Virus