Comparison of immune responses against foot-and-mouth disease virus induced by fusion proteins using the swine IgG heavy chain constant region or beta-galactosidase as a carrier of immunogenic epitopes.
Previously, we demonstrated that a fusion protein (Gal-FMDV) consisting of beta-galactosidase and an immunogenic peptide, amino acids (141-160)-(21-40)-(141-160), of foot-and-mouth disease virus (FMDV) VP1 protein induced protective immune responses in guinea pigs and swine. We now designed a new potential recombinant protein vaccine against FMDV in swine. The immunogenic peptide, amino acids (141-160)-(21-40)-(141-160) from the VP1 protein of serotype O FMDV, was fused to the carboxy terminus of a swine immunoglobulin G single heavy chain constant region and expressed in Escherichia coli. The expressed fusion protein (IgG-FMDV) was purified and emulsified with oil adjuvant. Vaccination twice at an interval of 3 weeks with the emulsified IgG-FMDV fusion protein induced an FMDV-specific spleen proliferative T-cell response in guinea pigs and elicited high levels of neutralizing antibody in guinea pigs and swine. All of the immunized animals were efficiently protected against FMDV challenge. There was no significant difference between IgG-FMDV and Gal-FMDV in eliciting immunity after vaccination twice in swine. However, when evaluating the efficacy of a single inoculation of the fusion proteins, we found that IgG-FMDV could elicit a protective immune response in swine, while Gal-FMDV only elicited a weak neutralizing activity and could not protect the swine against FMDV challenge. Our results suggest that the IgG-FMDV fusion protein is a promising vaccine candidate for FMD in swine.
Li
Guangjin
G
State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan University, Shanghai 200433, PR China.
Chen
Weizao
W
Yan
Weiyao
W
Zhao
Kai
K
Liu
Mingqiu
M
Zhang
Jun
J
Fei
Liang
L
Xu
Quanxing
Q
Sheng
Zutian
Z
Lu
Yonggan
Y
Zheng
Zhaoxin
Z
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D036022:Capsid Proteins / Q000276:immunology*; D005260:Female; D005536:Foot-and-Mouth Disease / Q000517:prevention & control*; D029544:Foot-and-Mouth Disease Virus / Q000276:immunology*; D006168:Guinea Pigs; D007127:Immunoglobulin Constant Regions / Q000235:genetics; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D008297:Male; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage* / Q000096:biosynthesis / Q000276:immunology; D013552:Swine; D014611:Vaccination / Q000662:veterinary*; D014765:Viral Vaccines / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology; D001616:beta-Galactosidase / Q000235:genetics / Q000276:immunology
D000914:Antibodies, Viral; D036022:Capsid Proteins; D007127:Immunoglobulin Constant Regions; D007143:Immunoglobulin Heavy Chains; D011993:Recombinant Fusion Proteins; C442501:VP1 protein, Foot-and-mouth disease virus; D014765:Viral Vaccines; D001616:beta-Galactosidase