J Gen Virol. 1997 Dec;78 ( Pt 12):3265-75. Unique Identifier : AIDSLINE
Two experimental feline immunodeficiency virus (FIV) vaccines were
tested, either alone or in combination, in four groups of cats (A-D).
One vaccine (SL3261-FIV) was composed of live attenuated Salmonella
typhimurium aroA (SL3261) strains expressing the capsid (Gag) and part
of the envelope (Env) proteins of FIV. The other was composed of FIV Gag
and Env proteins incorporated into immune-stimulating complexes
iscom-FIV). Cats of group A were immunized four times with SL3261-FIV.
Cats of group B were immunized twice with SL3261-FIV and then twice with
iscom-FIV. Cats of group C were immunized twice with SL3261 expressing
the B subunit of cholera toxin SL3261-CtxB) and then twice with
iscom-FIV. Cats of group D, which served as negative controls, were
immunized twice with SL3261-CtxB and then twice with iscom into which
the Gag and Env proteins of simian immunodeficiency virus (SIV) had been
incorporated (iscom-SIV). Two weeks after the last immunization, all
cats were challenged with FIV. At this time, cats immunized with
iscom-FIV (groups B and C) showed strong plasma antibody responses to
Gag and Env, whilst these responses were weak or undetectable in the
cats immunized four times with SL3261-FIV group A). Seven weeks after
FIV challenge, Env-specific antibody responses had increased
considerably in cats of all groups except group A. The mean virus loads
in the cats of this group proved to be lower than those of the other
groups at all time points, indicating partial protection.
*Feline Acquired Immunodeficiency Syndrome/IMMUNOLOGY *Immunodeficiency
Virus, Feline/IMMUNOLOGY *Salmonella typhimurium/IMMUNOLOGY *Vaccines,
Synthetic *Viral Vaccines