Intra-serotype SAT2 chimeric foot-and-mouth disease vaccine protects cattle against FMDV challenge.
The genetic diversity of the three Southern African Territories (SAT) types of foot-and-mouth disease virus (FMDV) reflects high antigenic variation, and indications are that vaccines targeting each SAT-specific topotype may be needed. This has serious implications for control of FMD using vaccines as well as the choice of strains to include in regional antigen banks. Here, we investigated an intra-serotype chimeric virus, vSAT2(ZIM14)-SAT2, which was engineered by replacing the surface-exposed capsid-coding region (1B-1D/2A) of a SAT2 genome-length clone, pSAT2, with that of the field isolate, SAT2/ZIM/14/90. The chimeric FMDV produced by this technique was viable, grew to high titres and stably maintained the 1B-1D/2A sequence upon passage. Chemically inactivated, oil adjuvanted vaccines of both the chimeric and parental immunogens were used to vaccinate cattle. The serological response to vaccination showed the production of strong neutralizing antibody titres that correlated with protection against homologous FMDV challenge. We also predicted a good likelihood that cattle vaccinated with an intra-serotype chimeric vaccine would be protected against challenge with viruses that caused recent outbreaks in southern Africa. These results provide support that chimeric vaccines containing the external capsid of field isolates induce protective immune responses in FMD host species similar to the parental vaccine.
Transboundary Animal Diseases Programme, Onderstepoort Veterinary Institute, Agricultural Research Council, Private Bag X05, Onderstepoort 0110, South Africa; Department of Microbiology and Plant Pathology, Faculty of Agricultural and Natural Sciences, University of Pretoria, Pretoria 0002, South Africa. Electronic address: mareef@arc.agric.za.
Francois F
FF
Maree
Department of Veterinary Tropical Diseases, Faculty of Veterinary Science University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa; Makerere University, College of Veterinary Medicine, Animal Resources and Biosecurity, PO Box 7062, Kampala, Uganda.
Peninah
P
Nsamba
Transboundary Animal Diseases Programme, Onderstepoort Veterinary Institute, Agricultural Research Council, Private Bag X05, Onderstepoort 0110, South Africa.
Paidamwoyo
P
Mutowembwa
Transboundary Animal Diseases Programme, Onderstepoort Veterinary Institute, Agricultural Research Council, Private Bag X05, Onderstepoort 0110, South Africa.
Lia S
LS
Rotherham
Transboundary Animal Diseases Programme, Onderstepoort Veterinary Institute, Agricultural Research Council, Private Bag X05, Onderstepoort 0110, South Africa.
Jan
J
Esterhuysen
Transboundary Animal Diseases Programme, Onderstepoort Veterinary Institute, Agricultural Research Council, Private Bag X05, Onderstepoort 0110, South Africa; Department of Veterinary Tropical Diseases, Faculty of Veterinary Science University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa.
Katherine
K
Scott
D000276:Adjuvants, Immunologic; D000353:Africa, Southern; D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D000940:Antigenic Variation; D036022:Capsid Proteins / Q000276:immunology*; D002417:Cattle; D005536:Foot-and-Mouth Disease / Q000517:prevention & control*; D029544:Foot-and-Mouth Disease Virus / Q000235:genetics / Q000254:growth & development / Q000276:immunology*; D009500:Neutralization Tests; D065288:Serogroup; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology; D014765:Viral Vaccines / Q000008:administration & dosage / Q000276:immunology
D000276:Adjuvants, Immunologic; D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D036022:Capsid Proteins; D015164:Vaccines, Inactivated; D014614:Vaccines, Synthetic; D014765:Viral Vaccines
Chimeric antigen; Foot-and-mouth disease virus; Intra-serotype chimera; Vaccine