title: Impact of persistent HIV replication on CD4 negative Vγ2Vδ2 T cells.
abstract: BACKGROUND
  CD4- Vγ2Vδ2 T cells are depleted during human immunodeficiency virus (HIV) infection but can recover to near normal levels in patients who spontaneously control viremia in the absence of therapy. By contrasting Vγ2Vδ2 T-cell numbers, phenotype, and T-cell receptor (TCR) repertoire, we investigate the dynamic tension between active immunity and progressive T-cell destruction during persistent viremia.
  
  
  METHODS
  Peripheral blood Vγ2Vδ2 T-cell levels and phenotypes were characterized by flow cytometry. Lymphoproliferation assays measured functional responses. Spectratyping characterized damage to the TCR repertoire.
  
  
  RESULTS
  Levels, responses to antigen and the proportion of T effector memory Vγ2Vδ2 T cells in patients with persistent viremia, were intermediate between patients with natural virus suppression (NVS) and patients receiving antiretroviral therapy. Damage to the TCR γ-2 chain repertoire and depletion of CD56+ Vγ2Vδ2 T cells were more pronounced in viremic patients, compared with antiretroviral therapy recipients and patients with natural virus suppression.
  
  
  CONCLUSIONS
  Characteristics of Vγ2Vδ2 T cells in viremic patients reflect both active responses (increasing cell numbers, better antigen responses, and higher proportion of effector memory cells) and ongoing damage (repertoire changes and loss of CD56+ cells). Unlike patients who control viremia to undetectable levels, Vγ2Vδ2 T cells are diminished during persistent viremia and may eventually be lost because of progressive destruction of the TCR repertoire.
authors.affiliation: Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
authors.forename: Sarah
authors.initials: S
authors.lastname: Boudová
authors.forename: Haishan
authors.initials: H
authors.lastname: Li
authors.forename: Mohammad M
authors.initials: MM
authors.lastname: Sajadi
authors.forename: Robert R
authors.initials: RR
authors.lastname: Redfield
authors.forename: C David
authors.initials: CD
authors.lastname: Pauza
mesh_terms: D000328:Adult; D005260:Female; D006678:HIV / Q000502:physiology*; D015658:HIV Infections / Q000276:immunology* / Q000821:virology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011948:Receptors, Antigen, T-Cell / Q000276:immunology / Q000378:metabolism; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D012189:Retrospective Studies; D013601:T-Lymphocytes / Q000276:immunology* / Q000821:virology; D014766:Viremia / Q000276:immunology; D014779:Virus Replication
chemical_list: D011948:Receptors, Antigen, T-Cell; D016692:Receptors, Antigen, T-Cell, gamma-delta