A Recombinant Rift Valley Fever Virus Glycoprotein Subunit Vaccine Confers Full Protection against Rift Valley Fever Challenge in Sheep.
Rift Valley fever virus (RVFV) is a mosquito-borne zoonotic pathogen causing disease outbreaks in Africa and the Arabian Peninsula. The virus has great potential for transboundary spread due to the presence of competent vectors in non-endemic areas. There is currently no fully licensed vaccine suitable for use in livestock or humans outside endemic areas. Here we report the evaluation of the efficacy of a recombinant subunit vaccine based on the RVFV Gn and Gc glycoproteins. In a previous study, the vaccine elicited strong virus neutralizing antibody responses in sheep and was DIVA (differentiating naturally infected from vaccinated animals) compatible. In the current efficacy study, a group of sheep (n = 5) was vaccinated subcutaneously with the glycoprotein-based subunit vaccine candidate and then subjected to heterologous challenge with the virulent Kenya-128B-15 RVFV strain. The vaccine elicited high virus neutralizing antibody titers and conferred complete protection in all vaccinated sheep, as evidenced by prevention of viremia, fever and absence of RVFV-associated histopathological lesions. We conclude that the subunit vaccine platform represents a promising strategy for the prevention and control of RVFV infections in susceptible hosts.
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
Bonto
B
Faburay
United States Department of Agriculture, Agricultural Research Service, Arthropod Borne Animal Disease Research Unit, Manhattan, Kansas, USA.
William C
WC
Wilson
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
Natasha N
NN
Gaudreault
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
A Sally
AS
Davis
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
Vinay
V
Shivanna
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
Bhupinder
B
Bawa
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
Sun Young
SY
Sunwoo
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
Wenjun
W
Ma
United States Department of Agriculture, Agricultural Research Service, Arthropod Borne Animal Disease Research Unit, Manhattan, Kansas, USA.
Barbara S
BS
Drolet
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
Igor
I
Morozov
United States Department of Agriculture, Agricultural Research Service, Arthropod Borne Animal Disease Research Unit, Manhattan, Kansas, USA.
D Scott
DS
McVey
Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA.
Juergen A
JA
Richt
D000818:Animals; D057134:Antibodies, Neutralizing / Q000378:metabolism; D000917:Antibody Formation / Q000276:immunology; D006023:Glycoproteins / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood; D008099:Liver / Q000473:pathology; D008198:Lymph Nodes / Q000473:pathology; D011994:Recombinant Proteins / Q000276:immunology*; D012295:Rift Valley Fever / Q000097:blood / Q000276:immunology* / Q000517:prevention & control*; D012296:Rift Valley fever virus / Q000378:metabolism* / Q000472:pathogenicity; D012756:Sheep / Q000276:immunology* / Q000821:virology; D012757:Sheep Diseases / Q000097:blood / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D013696:Temperature; D022223:Vaccines, Subunit / Q000276:immunology*; D014766:Viremia / Q000276:immunology; D014774:Virulence
D057134:Antibodies, Neutralizing; D006023:Glycoproteins; D007074:Immunoglobulin G; D011994:Recombinant Proteins; D022223:Vaccines, Subunit