       Document 0623
 DOCN  M9630623
 TI    Limited viral spread and rapid immune response in lymph nodes of
       macaques inoculated with attenuated simian immunodeficiency virus.
 DT    9603
 AU    Chakrabarti L; Baptiste V; Khatissian E; Cumont MC; Aubertin AM;
       Montagnier L; Hurtrel B; Unite d'Oncologie Virale, Institut Pasteur,
       Paris, France.
 SO    Virology. 1995 Nov 10;213(2):535-48. Unique Identifier : AIDSLINE
       MED/96074529
 AB    A comparative study was undertaken to characterize the very early events
       that distinguish attenuated and pathogenic simian immunodeficiency virus
       (SIV) infections. Three rhesus macaques were inoculated with the
       attenuated SIVmac 251 delta nef virus, and three others with a virus of
       intermediate phenotype, SIVmac 239 nef stop. They were compared to four
       macaques inoculated with the pathogenic SIVmac 251 isolate. Lymph nodes
       (LN) taken between 7 days and 2 months postinoculation were analyzed for
       SIV expression by in situ hybridization. During acute infection, SIV 21
       delta nef infected 1 to 1.5 log10 fewer cells in LN tissue than the
       pathogenic SIV 251 isolate. The reduction was more marked in the blood,
       as SIV 251 delta nef infected 2 to 3 log10 fewer PBMC than the isolate
       and did not yield detectable antigenemia. Morphometric measurements
       showed that the development of germinal centers (GC) was more rapid in
       the delta nef infection, which led to a more efficient trapping of viral
       particles, and could account for antigenemia clearance. The SIV 239 nef
       stop clone reverted to a nef+ genotype at Week 2, but induced a lower
       viral burden than a directly pathogenic virus. The kinetics of GC
       development was rapid, indicating that SIV 239 nef stop induced an
       immune response similar to that seen in attenuated infection. This study
       provides evidence that attenuated SIV elicits a more rapid immune
       response than pathogenic SIV and suggests that an early
       immunosuppressive episode may facilitate the dissemination of pathogenic
       SIV.
 DE    Amino Acid Sequence  Animal  Antibodies, Viral/BLOOD  Base Sequence
       Comparative Study  Disease Progression  DNA Primers  DNA, Viral/ANALYSIS
       Germinal Center/IMMUNOLOGY  Kinetics  Leukocytes, Mononuclear/VIROLOGY
       Lymph Nodes/IMMUNOLOGY/*VIROLOGY  Macaca mulatta  Molecular Sequence
       Data  Simian Acquired Immunodeficiency Syndrome/IMMUNOLOGY/*VIROLOGY
       Support, Non-U.S. Gov't  SIV/IMMUNOLOGY/ISOLATION & PURIF/*PATHOGENICITY
       Viremia  Virulence  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

