Feline leukaemia virus: protective immunity is mediated by virus-specific cytotoxic T lymphocytes.
Feline leukaemia virus (FeLV) nucleic acid vaccination of domestic cats affords protection against viraemia and the development of latency without inducing antiviral antibodies.1 To determine the contribution of cell-mediated immunity to the control of virus replication and clearance from the host, FeLV-specific cytotoxic T lymphocyte (CTL) responses were compared in vaccine-protected, transiently viraemic, and persistently viraemic cats. Vaccinal immunity was associated with the detection of higher levels of virus-specific effector CTL in the peripheral blood and lymphoid organs to FeLV Gag/Pro and Env antigens than those observed in unvaccinated control, persistently viraemic cats (P<0.001). Likewise, higher levels of virus-specific CTLs were also observed in transiently viraemic cats which recovered following exposure to FeLV. In cats that controlled their infection, recognition of Gag/Pro antigens was significantly higher than the recognition of Env antigens. This is the first report highlighting the very significant role that virus-specific CTL have in determining the outcome of FeLV infection in either vaccinated cats or cats recovering naturally from FeLV exposure.
Flynn
J N
JN
Retrovirus Research Laboratory, Department of Veterinary Pathology, University of Glasgow, Glasgow, UK.
Hanlon
L
L
Jarrett
O
O
D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis; D002415:Cats; D003602:Cytotoxicity, Immunologic; D007111:Immunity, Cellular; D005256:Leukemia Virus, Feline / Q000276:immunology*; D012192:Retroviridae Infections / Q000276:immunology* / Q000517:prevention & control; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014412:Tumor Virus Infections / Q000276:immunology* / Q000517:prevention & control; D014611:Vaccination; D019444:Vaccines, DNA / Q000276:immunology; D014765:Viral Vaccines / Q000276:immunology; D014766:Viremia / Q000276:immunology
D000914:Antibodies, Viral; D019444:Vaccines, DNA; D014765:Viral Vaccines