Document 0685
 DOCN  M9650685
 TI    Properties of virus-like particles produced by SIV-chronically infected
       human cell clones.
 DT    9605
 AU    Kraiselburd EN; Torres JV; Dept. of Microbiology and Medical Zoology,
       UPR School of; Medicine, San Juan 00936-5067, Puerto Rico.
 SO    Cell Mol Biol (Noisy-le-grand). 1995;41 Suppl 1:S41-52. Unique
       Identifier : AIDSLINE MED/96171634
 AB    SIVsm chronically infected cultures were obtained after infection of
       CEMX174 cells with either SIVsmH3 or SIVsmE660. These phenotypically CD4
       cells, formed syncytia but only when cocultivated with CD4+ cells.
       Single cell clones were derived from these cultures and examined for the
       production of virus-specific proteins. The majority of the clones
       expressed SIV p27 antigen and low levels of virus reverse transcriptase
       activity. Western blot analysis, performed with either monoclonal or
       polyclonal sera, showed that a chronically infected clone (B7) produced
       particles which contained envelope (gp135 and gp43), gag precursors and
       gag proteins (p27, p16 and p8). However, these particles (SIVsmB7)
       lacked detectable levels of vpx and of integrase, and contained several
       fusion proteins which expressed viral protease antigens. This defective
       virus failed to infect established CD4+ cell lines, as well as primary
       cultures of macrophages and of peripheral blood lymphocytes, obtained
       both from humans and from rhesus macaques. Lack of infection correlated
       with lack of viral DNA detection by PCR amplification of genomic DNA
       extracted from these cell cultures. In addition, SIVsmB7 virus lacked
       infectivity in vivo. Rhesus macaques inoculated with high concentrations
       of SIVsmB7 showed no viremia and their PBMC were PCR negative. Thus, B7
       cells produced stable, non-infectious virus mutants, which contained env
       and gag proteins, but lacked detectable amounts of vpx and of enzymes
       required for virus replication. Due to the high constitutive expression
       of this virus-like particle, we are now testing this preparation as a
       vaccine.
 DE    Animal  Base Sequence  Cell Fusion  Clone Cells/*VIROLOGY
       Cytopathogenic Effect, Viral  CD4-Positive T-Lymphocytes/*VIROLOGY
       Defective Viruses/GENETICS/ISOLATION & PURIF/*PHYSIOLOGY  DNA,
       Viral/ANALYSIS  Gene Products, gag/ANALYSIS  Genes, Viral  Human
       Inclusion Bodies, Viral/*PHYSIOLOGY  Macaca mulatta/VIROLOGY
       Macrophages/VIROLOGY  Microscopy, Electron  Molecular Sequence Data
       Polymerase Chain Reaction  Proviruses/GENETICS/ISOLATION & PURIF
       Repetitive Sequences, Nucleic Acid  Retroviridae
       Proteins/BIOSYNTHESIS/GENETICS  Support, U.S. Gov't, P.H.S.
       SIV/GENETICS/ISOLATION & PURIF/*PHYSIOLOGY  Virus Replication  JOURNAL
       ARTICLE

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