Archives of Biological Sciences 2015 Volume 67, Issue 1, Pages: 41-55
https://doi.org/10.2298/ABS141003004Z
Full text ( 1003 KB)
Characterization and immunogenicity of rLipL32/1-LipL21-OmpL1/2 fusion protein as a novel immunogen for a vaccine against Leptospirosis
Zhao Xin (Zhejiang University School of Medicine, the First Affiliated Hospital, Division of Basic Medical Microbiology, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, P.R. China + Zhejiang University School of Medicine)
Wang Jiang (Zhejiang University School of Medicine, Department of Medical Microbiology and Parasitology, Hangzhou, Zhejiang, P.R. China)
Ge Yu-Mei (Zhejiang University School of Medicine, the First Affiliated Hospital, Division of Basic Medical Microbiology, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, P.R. China + Zhejiang University School of Medicine)
Lin Xu-Ai (Zhejiang University School of Medicine, the First Affiliated Hospital, Division of Basic Medical Microbiology, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, P.R. China + Zhejiang University School of Medicine)
Yan Jie (Zhejiang University School of Medicine, the First Affiliated Hospital, Division of Basic Medical Microbiology, State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, P.R. China + Zhejiang University School of Medicine)
Sun Ai-Hua (Zhejiang Medical College, Faculty of Basic Medicine, Hangzhou, Zhejiang, P. R. China)
Vaccination is an effective strategy to prevent leptospirosis, a global
zoonotic disease caused by infection with pathogenic Leptospira species.
However, the currently used multiple-valence vaccine, which is prepared with
whole cells of several Leptospira serovars, has major side effects, while its
cross-immunogenicity among different Leptospira serovars is weak. LipL32,
LipL21 and 2 OmpL1 have been confirmed as surface-exposed antigens in all
pathogenic Leptospira strains, but their immunoprotective efficiency needs to
be improved. In the present study, we generated a fusion gene
lipL32/1-lipL21-ompL1/2 using primer-linking PCR and an engineered E. coli
strain to express the recombinant fusion protein rLipL32/1-LipL21-OmpL1/2
(rLLO). Subsequently, the expression conditions were optimized using a
central composite design that increased the fusion protein yield 2.7-fold.
Western blot assays confirmed that rLLO was recognized by anti-rLipL32/1,
anti-rLipL21, and anti-rOmpL1/2 sera as well as 98.5% of the sera from
leptospirosis patients. The microscopic agglutination test (MAT) demonstrated
that rLLO antiserum had a stronger ability to agglutinate the strains of
different Leptospira serovars than the rLipL32/1, rLipL21, and rOmpL1/2
antisera. More importantly, tests in hamsters showed that rLLO provided
higher immunoprotective rates (91.7%) than rLipL32/1, rLipL21 and rOmpL1/2
(50.0-75.0%). All the data indicate that rLLO, a recombinant fusion protein
incorporating three antigens, has increased antigenicity and immunoprotective
effects, and so can be used as a novel immunogen to develop a universal
genetically engineered vaccine against leptospirosis.
Keywords: Leptospirosis, triple antigen, genetically engineered vaccine, immunogenicity