title: Antiretroviral therapy does not block the secretion of the human immunodeficiency virus tat protein.
abstract: Tat is a viral protein secreted from HIV infected cells and extra cellular Tat is suspected to prevent destruction of HIV infected cells from cells of the cellular immunity. The effect of anti retroviral therapy (ART) on Tat secretion has never been investigated. In this study, we tested for antibody reactivity against Tat variants representative of the main HIV subtypes in HIV positive patients receiving ART with undetectable viral loads ( < 40 copies/mL) over the course of one year with a blood sampling every three months. For each of theses five blood sampling, an average of 50 % of patients had Anti-Tat IgG, it turned out that 86% of patients could recognize Tat at least in one blood sampling during the course of the study. Amazingly, anti-Tat IgG appeared and/or disappeared in 66 % of patients. Only 20% had anti-Tat IgG remaining persistently while 14% were consistently without anti Tat IgG in the five blood sampling. No significant correlation was found between anti-Tat IgG and CD4+ T cell, CD8+ T cell and B cell counts revealing the incapacity of these anti Tat IgG to neutralize extra cellular Tat. Interestingly the absence and then the appearance of anti-Tat IgG in patients suggest the presence of HIV infected cells in the blood that may constitute a significant reservoir of HIV infected cells. As a conclusion antiretroviral therapy does not block the secretion of Tat and may explain why HIV infected cells can survive in spite of an effective ART treatment.
authors.affiliation: University of the Mediterranean, Marseille cedex, France.
authors.forename: Sonia
authors.initials: S
authors.lastname: Mediouni
authors.forename: Albert
authors.initials: A
authors.lastname: Darque
authors.forename: Gilbert
authors.initials: G
authors.lastname: Baillat
authors.forename: Isabelle
authors.initials: I
authors.lastname: Ravaux
authors.forename: Catherine
authors.initials: C
authors.lastname: Dhiver
authors.forename: Herve
authors.initials: H
authors.lastname: Tissot-Dupont
authors.forename: Malika
authors.initials: M
authors.lastname: Mokhtari
authors.forename: Herve
authors.initials: H
authors.lastname: Moreau
authors.forename: Catherine
authors.initials: C
authors.lastname: Tamalet
authors.forename: Corinne
authors.initials: C
authors.lastname: Brunet
authors.forename: Pascale
authors.initials: P
authors.lastname: Paul
authors.forename: Francoise
authors.initials: F
authors.lastname: Dignat-George
authors.forename: Andreas
authors.initials: A
authors.lastname: Stein
authors.forename: Philippe
authors.initials: P
authors.lastname: Brouqui
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Spector
authors.forename: Grant R
authors.initials: GR
authors.lastname: Campbell
authors.forename: Erwann P
authors.initials: EP
authors.lastname: Loret
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D015696:Gene Products, tat / Q000097:blood / Q000276:immunology / Q000378:metabolism*; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged
chemical_list: D019380:Anti-HIV Agents; D015696:Gene Products, tat; D007074:Immunoglobulin G