Vaccination with fixed feline immunodeficiency virus (FIV) infected cells: Protection, breakthrough and specificity of response
VACCINE
Authors: Bishop, SA; Stokes, CR; GruffyddJones, TJ; Whiting, CV; Humphries, JE; Osborne, R; Papanastasopoulou, M; Harbour, DA
Abstract
Infection of cats with feline immunodeficiency virus (FIV), a naturally occurring lentivirus infection of cats which causes an AIDS-like disease, has generated considerable interest as an animal model for HIV vaccination. This paper reports on experiments performed to examine the potential of a fixed infected cell vaccine to confer protection against intraperitoneal challenge with cell-free FIV. The cell vaccine was highly immunogenic and elicited antibody responses to virus core antigen, p24, high virus neutralizing (VN) antibody titres, and antibodies which recognized cellular components of the vaccine. Whilst protection, assessed by the inability to detect infectious virus by virus isolation or polymerase chain reaction, against homologous but not heterologous FIV isolates was apparent up to week 12 post-challenge, when cats were monitored longer up to week 50 post-challenge a breakthrough in vaccine protection against homologous virus was observed. Protection could not be correlated with levels of antibody to p24 or VN antibody titres. In contrast with simian immunodeficiency virus vaccine studies in macaques there was no clear evidence that antibodies recognizing cellular components of the vaccine, including MHC class I and II antigens, conferred any protective effect following challenge. These results indicate that long-term post-challenge monitoring for infection is essential in lentivirus vaccine trials. Crown Copyright (C) 1996 Published by Elsevier Science Ltd.
High prevalence of Borna disease virus in domestic cats with neurological disorders in Japan
VETERINARY MICROBIOLOGY
Authors: Nakamura, Y; Watanabe, M; Kamitani, W; Taniyama, H; Nakaya, T; Nishimura, Y; Tsujimoto, H; Machida, S; Ikuta, K
Abstract
A total of 15 (T-1-T-15) domestic cats with neurological disorders in Tokyo area were examined for association with Borna disease virus (BDV), None had detectable antibodies to feline immunodeficiency virus (FIV), feline leukemia virus, feline infectious peritonitis virus and Toxoplasma gondii, and only cat T-8 had detectable antibody to FIV. Serological and molecular epidemiological studies revealed a significantly high prevalence of BDV infection in these cats: antibodies against BDV p24 and/or p40 proteins in 10/15 (66.7%) and p24 and/or p40 RNA in peripheral blood mononuclear cells in 8/15 (53,3%), Further, in situ hybridization and immunohistochemistry analyses of the autopsied brain samples derived from one of the cats (T-15) revealed BDV RNA predominantly in neuronal cells in restricted regions, such as olfactory bulb and medulla of cerebrum. Thus, BDV is present in Japanese domestic cats with neurological disorders at a high prevalence. (C) 1999 Elsevier Science B,V, All rights reserved.