A molecular approach to the identification of cytotoxic T-lymphocyte epitopes within equine herpesvirus 1.
Equine herpesvirus 1 (EHV-1) causes respiratory and neurological disease and abortion in horses. Animals with high frequencies of cytotoxic T lymphocytes (CTL) show reduced severity of respiratory disease and frequency of abortion, probably by CTL-mediated control of cell-associated viraemia. This study aimed to identify CTL epitopes restricted by selected major histocompatibility complex (MHC) class I alleles expressed in the equine leukocyte antigen (ELA) A3 haplotype. Effector CTL were induced from EHV-1-primed ponies and thoroughbreds with characterized MHC class I haplotypes and screened against P815 target cells transfected with selected EHV-1 genes and MHC class I genes. Targets that expressed EHV-1 gene 64 and the MHC B2 gene were lysed by effector CTL in a genetically restricted manner. There was no T-cell recognition of targets expressing either the MHC B2 gene and EHV-1 genes 2, 12, 14, 16, 35, 63 or 69, or the MHC C1 gene and EHV-1 genes 12, 14, 16 or 64. A vaccinia virus vector encoding gene 64 (NYVAC-64) was also investigated. Using lymphocytes from ELA-A3 horses, the recombinant NYVAC-64 virus induced effector CTL that lysed EHV-1-infected target cells; the recombinant virus also supplied a functional peptide that was expressed by target cells and recognized in an MHC-restricted fashion by CTL induced with EHV-1. This construct may therefore be used to determine the antigenicity of EHV-1 gene 64 for other MHC haplotypes. These techniques are broadly applicable to the identification of additional CTL target proteins and their presenting MHC alleles, not only for EHV-1, but for other equine viruses.
Kydd
Julia H
JH
Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU, UK.
Davis-Poynter
N J
NJ
Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU, UK.
Birch
J
J
Institute for Animal Health, Compton, Newbury, Berkshire RG20 7NN, UK.
Hannant
D
D
Centre for Preventive Medicine, Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk CB8 7UU, UK.
Minke
J
J
Merial SAS, 254 rue Marcel Mérieux, 69007 Lyon, France.
Audonnet
J-C
JC
Merial SAS, 254 rue Marcel Mérieux, 69007 Lyon, France.
Antczak
D F
DF
James A. Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Ellis
Shirley A
SA
Institute for Animal Health, Compton, Newbury, Berkshire RG20 7NN, UK.
D000483:Alleles; D000818:Animals; D000956:Antigens, Viral / Q000235:genetics; D001483:Base Sequence; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000235:genetics; D000939:Epitopes / Q000235:genetics; D005805:Genes, MHC Class I; D005814:Genes, Viral; D005822:Genetic Vectors; D006566:Herpesviridae Infections / Q000235:genetics / Q000276:immunology / Q000662:veterinary / Q000821:virology; D004861:Herpesvirus 1, Equid / Q000235:genetics / Q000276:immunology*; D006734:Horse Diseases / Q000235:genetics / Q000276:immunology / Q000821:virology; D006736:Horses; D066298:In Vitro Techniques; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014162:Transfection; D014616:Vaccinia virus / Q000235:genetics / Q000276:immunology
D000956:Antigens, Viral; D004279:DNA, Viral; D000939:Epitopes