Establishment of infection of animals with a viral clone will be important for investigating viral determinants of pathogenesis and monitoring sequence changes in the viral genome in vivo and may find utility as a means of immunization with live-attenuated virus. To test the efficiency of intramuscular (im) injection of cloned proviral plasmid DNA for establishing feline immunodeficiency virus (FIV) infection in specific pathogen-free (SPF) cats, groups of cats were inoculated by the im route with 300, 100, or 30 μg of plasmid DNA containing the infectious molecular clone, FIV-pPPR. A fourth group of cats was inoculated intradermally with 30 μg of FIV-pPPR plasmid DNA. For comparison, a fifth group received 103 TCID50 of a live virus stock of FIV-pPPR by intraperitoneal inoculation. Inoculation by im injection with 100 to 300 μg of infectious FIV-pPPR proviral DNA produced infection detectable by both antiviral antibody and virus isolation from peripheral blood mononuclear cells. Inoculation by im injection with 30 μg of proviral DNA resulted in infection in two of three inoculated cats. Intradermal infection with 30 μg of proviral DNA induced infection in one of three cats. Induction of antiviral antibody and viremia was delayed in cats inoculated with 30 μg compared to cats inoculated with either 100 or 300 μg of proviral DNA. This study indicates that cloned FIV proviral DNA may replace infectious virion preparations as inocula for pathogenesis and immunization studies.
ASJC Scopus subject areas
- Infectious Diseases