title: Low level of regulatory T cells and maintenance of balance between regulatory T cells and TH17 cells in HIV-1-infected elite controllers.
abstract: BACKGROUND
  A subgroup of HIV-1-infected individuals, elite controllers, have spontaneous viral control and offer an exceptional opportunity to study virological and immunolocigal factors of possible involvement in control of HIV-1 infection.
  
  
  METHODS
  The frequencies of Tregs and TH17 cells was evaluated and correlated to markers of disease progression in peripheral blood mononuclear cells from 3 different groups of individuals infected with HIV-1: treatment-naive viremic individuals, individuals on successful highly active antiretroviral therapy, and elite controllers. In addition, a group of HIV-1-negative individuals were included.
  
  
  RESULTS
  We demonstrate that elite controllers have lower levels of Tregs compared with HIV-1-infected viremic individuals, but that the low Treg level does not differ between individuals with HIV-1 control, whether natural or therapy induced. We also show that T-cell activation and proliferation both correlate to the level of Tregs. Finally, the TH17/Treg ratio was similar in Elite Controllers and uninfected controls, whereas in viremic and treated HIV-1-infected individuals, the TH17/Treg ratio was lower compared with uninfected controls.
  
  
  CONCLUSIONS
  We show that one feature of spontaneous HIV-1 control is a maintained balance between regulatory T cells and TH17 cells.
authors.affiliation: Department of Virology, Statens Serum Institut, Copenhagen, Denmark.
authors.forename: Lea
authors.initials: L
authors.lastname: Brandt
authors.forename: Thomas
authors.initials: T
authors.lastname: Benfield
authors.forename: Helene
authors.initials: H
authors.lastname: Mens
authors.forename: Louise Nygaard
authors.initials: LN
authors.lastname: Clausen
authors.forename: Terese L
authors.initials: TL
authors.lastname: Katzenstein
authors.forename: Anders
authors.initials: A
authors.lastname: Fomsgaard
authors.forename: Ingrid
authors.initials: I
authors.lastname: Karlsson
mesh_terms: D004797:Enzyme-Linked Immunosorbent Assay; D015483:HIV Antibodies / Q000097:blood; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D012367:RNA, Viral / Q000097:blood; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000502:physiology*; D058504:Th17 Cells / Q000276:immunology / Q000502:physiology*; D019562:Viral Load; D014766:Viremia
chemical_list: D015483:HIV Antibodies; D012367:RNA, Viral