Dose response effects of feline immunodeficiency virus PPR strain infection in cats

Abstract

Feline immunodeficiency virus (F1V) causes an immune phics. deficiency disease in cats similar to HIV-AIDS in humans. FIV-specific antibodies have been found in symptomatic and asymptomatic, domestic and non-domestic, cats world-wide. Little is known about the illness occurring immediately after infection with FIV. Fifteen specific-pathogen free (SPF) cats were inoculated with SOTCIDSO, 250TClD50 or 12501C1950 of the FIV-PPR strain and observed during the first eight weeks post-inoculation. Transient lymphadenopathy (day 4, 5 and 14) was detected in 3 cats in the 12501C1D50 group, and 2 in the 250-1-C1D50 group. 250TCID50 group and nasal discharge was observed in the 1250-1-Cr50 group. Between weeks 3-7, FIV specific antibodies were confirmed in the all of the inoculated animals. Sneezing was reported in one cat in the neither neutropenia nor nymphomania were detected by complete blood counts within this time frame. [] ratios fell to near 1 over the course of the experiment in all animals inoculated. Virus was detected by virus isolation in all animals inoculated by week 2 and from 13/ 15 by PCR by week 8. During weeks 4-6, prodigal DNA was undetectable in those animals previously PCR positive. Virus replication may be suppressed by mycotoxic T-lymphocytes (CFL), neutralizing antibodies and/ or cell-derived anti-FIV factors not yet fully characterized. Two of three cats tested in both the 250TCID50 and 1250TC1D50 groups had FW-specific CT'L killing. A11 cats tested for neurological manifestations of FIWPPR infection in the 1250TCID50 group had hindlimb dysfunction or behavioral changes, whereas the SOTCIDSO and negative control groups were normal. During the first eight weeks post inoculation, some of the classical signs of FIV infection, lymphadenopathy, upper respiratory difficulties and seroconversion appear to be dose responsive. [] ratios, virus isolation and CI'L mediated killing were not dose responsive.