title: T-cell proliferation to subinfectious SIV correlates with lack of infection after challenge of macaques.
abstract: OBJECTIVE
  To analyze correlates of protection in macaques exposed to SIV.
  
  
  METHODS
  Peripheral blood mononuclear cells (PBMC) from macaques inoculated intrarectally with various dilutions of SIV were examined for their in vitro proliferative response to SIV envelope peptides and generation of SIV-specific antibodies. Some macaques previously exposed intravenously to subinfectious doses of SIV were subsequently challenged 16 months later with an infectious intrarectal dose of SIV.
  
  
  RESULTS
  The viral-specific immune responses of macaques exposed to infectious doses of SIV were characterized by generation of antibodies and weak or undetectable T-cell-mediated responses. In contrast, macaques inoculated with doses of SIV below the threshold required for seroconversion and recovery of virus exhibited T-cell proliferation in response to SIV envelope synthetic peptides. The macaques that had previously been exposed to SIV resisted the subsequent virus challenge, whereas the naive macaques (never exposed to SIV) all became infected.
  
  
  CONCLUSIONS
  The inability to productively infect macaques previously exposed to subinfectious doses of SIV suggests that a T-cell-mediated response may confer long-term protection against infection, and that AIDS vaccines should be designed to optimize the cellular arm of the immune response.
authors: Experimental Immunology Branch, National Cancer Institute, Bethesda, Maryland.
authors: M
authors: M
authors: Clerici
authors: E A
authors: EA
authors: Clark
authors: P
authors: P
authors: Polacino
authors: I
authors: I
authors: Axberg
authors: L
authors: L
authors: Kuller
authors: N I
authors: NI
authors: Casey
authors: W R
authors: WR
authors: Morton
authors: G M
authors: GM
authors: Shearer
authors: R E
authors: RE
authors: Benveniste
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D000956:Antigens, Viral / Q000276:immunology; D002455:Cell Division; D002478:Cells, Cultured; D008213:Lymphocyte Activation; D008252:Macaca fascicularis; D008254:Macaca nemestrina; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry / Q000276:immunology; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology*; D015302:Simian Immunodeficiency Virus / Q000276:immunology* / Q000302:isolation & purification; D013601:T-Lymphocytes / Q000276:immunology*; D013936:Thymidine / Q000378:metabolism
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D010455:Peptides; D013936:Thymidine