DEVELOPMENT CLINICAL-DISEASE IN CATS EXPERIMENTALLY INFECTED WITH FELINE IMMUNODEFICIENCY VIRUS

Cats naturally infected with feline immunodeficiency virus (FIV) devel op an AIDS-like syndrome whereas experimentally infected cats do not. To investigate the role of cofactors in the development of this diseas e in cats, 7 specific pathogen-free (SPF) and 12 random-source (RS) ca ts were infected with FIV. Over 4 years, infected cats developed simil ar phenotypic and functional immune abnormalities characterized by ear ly and chronic inversion of CD4(+):CD8(+) cell ratios and significantl y decreased mitogen responses compared with controls. Beginning 18-24 months after infection, 10 RS cats developed chronic clinical disease typical of feline AIDS, including stomatitis and recurrent upper respi ratory disease; 4 SPF cats also developed chronic clinical disease, 2 with neurologic disease and 2 with B cell lymphomas. Thus, immunologic background is important in the type of disease that develops in cats infected with FIV, and FIV represents a promising animal model for stu dying the immunopathogenesis of AIDS in humans.