Feline immunodeficiency virus (FIV)-specific cytotoxic T lymphocytes from chronically infected cats are induced in vitro by retroviral vector-transduced feline T cells expressing the FIV capsid protein.
We have previously reported the presence of feline immunodeficiency virus (FIV)-specific, major histocompatibility complex (MHC)-restricted cytolytic T lymphocytes (CTL) in experimentally FIV-infected cats. However, the fine specificity of the CTL and the role of individual FIV proteins in inducing FIV-specific CTL responses remain unknown. In this study, we examined the in vitro induction and activity of FIV p24 capsid-specific CTL obtained from cats that had been experimentally infected with FIV Petaluma for 30 to 56 months. An amphotropic murine retroviral vector was used to generate transgenic primary feline T lymphoblasts that expressed the FIV capsid protein. When the autologous capsid-transduced T cells were used in vitro to stimulate CTL responses from peripheral blood mononuclear cells of chronically infected cats, MHC-restricted lysis of virus-infected target cells was observed. The majority of the CTL expressed CD8, and depletion of this population, but not CD4+ cells, effectively diminished the CTL activity. When the autologous capsid-transduced T cells were used as target cells, lysis by capsid-induced effectors was not observed. Analysis of capsid-transduced T cell clones revealed a variable and low level of capsid expression among the clones. This study demonstrates the potential for using retroviral vectors as a means of inducing CTL effector cells that will specifically kill lentivirus-infected cells during lentiviral infection.
Song
W
W
Department of Veterinary Pathobiology, Texas A&M University, College Station, USA.
Collisson
E W
EW
Li
J
J
Wolf
A M
AM
Elder
J H
JH
Grant
C K
CK
Brown
W C
WC
D000818:Animals; D001483:Base Sequence; D002213:Capsid / Q000096:biosynthesis*; D002415:Cats; D002460:Cell Line; D003001:Cloning, Molecular; D003602:Cytotoxicity, Immunologic; D017931:DNA Primers; D016181:Feline Acquired Immunodeficiency Syndrome / Q000276:immunology*; D015870:Gene Expression; D016089:Immunodeficiency Virus, Feline / Q000276:immunology* / Q000502:physiology; D008285:Major Histocompatibility Complex; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000821:virology*; D014161:Transduction, Genetic; D014162:Transfection
D017931:DNA Primers