Vaccination of ponies with the IE gene of EHV-1 in a recombinant modified live vaccinia vector protects against clinical and virological disease.
Vet Immunol Immunopathol
; 135(1-2): 108-117, 2010 May 15.
Article
in En
| MEDLINE
| ID: mdl-20018383
ABSTRACT
The control of EHV-1 infection by cytotoxic T-cell responses (CTL) via a reduction in cell associated viremia remains an important goal in horses. Unfortunately, current vaccines are inefficient at inducing these responses. We have identified the immediate early (IE) gene of EHV-1 as a potent stimulator of virus-specific CTL responses in ponies expressing a specific MHC class I serological haplotype (A3/B2). This study was designed to determine if vaccination of A3/B2 MHC I positive ponies with the IE gene could induce protection and immune responses associated with cell mediated immunity. Ponies expressing the MHC-I A3/B2 haplotype (A3/B2 vaccinates) and ponies with a different MHC I haplotype (either non-A3 vaccinates or A3-non-B2 vaccinates) were vaccinated with a recombinant modified vaccinia Ankara (rMVA) vector expressing the IE gene on 3 occasions and vaccinates and unvaccinated controls were challenge infected 8 weeks after the last vaccination. Interferon gamma (IFN-gamma) mRNA and antibody titers were determined throughout the study and clinical signs, nasal virus shedding and viremia were determined following challenge infection. Vaccination of A3/B2 vaccinates conferred significant clinical protection and a significant reduction in EHV-1 viremia. IFN-gamma mRNA increased significantly following vaccination in the A3/B2 vaccinates. Antibody titers remained low until after challenge infection, indicating that no accidental field acquired or recrudescent EHV-1 infection had occurred. In summary, this is an important study showing that vaccination of ponies with the EHV-1 IE protein provides not only reduction in clinical disease but also reduction of cell associated viremia, which is a prerequisite for the prevention of abortion and neurological disease.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Herpesvirus 1, Equid
/
Herpesviridae Infections
/
Herpesvirus Vaccines
/
Horse Diseases
Limits:
Animals
Language:
En
Journal:
Vet Immunol Immunopathol
Year:
2010
Document type:
Article
Affiliation country:
United States