       Document 0111
 DOCN  M9630111
 TI    Differing T-cell requirements for recombinant retrovirus vaccines.
 DT    9603
 AU    Hasenkrug KJ; Brooks DM; Nishio J; Chesebro B; Laboratory of Persistent
       Viral Diseases, Rocky Mountain; Laboratories, Hamilton, Montana 59840,
       USA.
 SO    J Virol. 1996 Jan;70(1):368-72. Unique Identifier : AIDSLINE
       MED/96099452
 AB    Friend murine leukemia virus is a retrovirus complex that induces rapid
       erythroleukemia and immunosuppression in susceptible strains of adult
       mice. Using this model, we directly examined the T-cell subsets required
       for a protective retrovirus vaccine. Paradoxically, recovery in mice
       immunized with a chimeric envelope containing only T-helper (TH) and
       B-cell epitopes was dependent on CD8+ T cells as well as CD4+ T cells
       despite the fact that the vaccine contained no CD8+ cytolytic
       T-lymphocyte (CTL) epitopes. However, the requirement for CD8+ T cells
       was overcome by inclusion of additional TH and B-cell epitopes in the
       immunizing protein. These additional epitopes primed for more rapid
       production of virus-neutralizing antibody which appeared to limit virus
       spread sufficiently to protect even in the absence of CD8+ T cells.
       Inclusion of an immunodominant CTL epitope in the vaccine was not
       sufficient to overcome dependence on CD4+ T cells. These data suggest
       that TH priming is more critical for retrovirus immunity than CTL
       priming.
 DE    Amino Acid Sequence  Animal  Antigens, Viral/*IMMUNOLOGY  Chimeric
       Proteins/IMMUNOLOGY  CD4-Positive T-Lymphocytes/IMMUNOLOGY  CD8-Positive
       T-Lymphocytes/IMMUNOLOGY  Epitopes/ANALYSIS  Female  Friend
       Virus/*IMMUNOLOGY  Lymphocyte Depletion  Male  Mice  Molecular Sequence
       Data  T-Lymphocyte Subsets/*IMMUNOLOGY/METABOLISM  T-Lymphocytes,
       Cytotoxic/IMMUNOLOGY  Vaccination  Viral Envelope
       Proteins/GENETICS/IMMUNOLOGY  Viral Vaccines/*IMMUNOLOGY  JOURNAL
       ARTICLE

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

