Background: Rotavirus is the most common cause of infectious diarrhea in infants and
young children around the world. The inner capsid protein VP6 has been discussed as alternative
vaccine as it can induce cross-protective immune responses against different RV strai. The use of
ferritin nanoparticle may enhance the immunogenicity of the subunit vaccine.
Objective: In this article, our motivation is to design and obtain a self-assemble rotavirus
nanoparticle vaccine which can induce efficiency immune response.
Methods: The VP6 protein was fused with ferritin and expressed in the Escherichia coli expression
system. The recombinant VP6-ferritin (rVP6-ferritin) protein was purified by His-tag affinity
chromatography and fast protein liquid chromatography. Transmission electron micrographic
analysis was used to detect the nanostructure of the self-assembled protein. Mice were gavage with
the protein and ELISA was used to detect the titer of the VP6 specific antibody.
Results: The recombined VP6-ferritin was expressed in the Escherichia coli as an inclusion body
form and the purified protein has similar antigenicity to rotavirus VP6. Transmission electron
micrographic analysis of rVP6-ferritin exhibited spherical architecture with a uniform size
distribution, which is similar to the ferritin nanocage. Immune response analysis showed that mice
immunized by rVP6-ferritin protein induced 8000 (8000±1093) anti-VP6 IgG titers or 1152
(1152±248.8) anti-VP6 IgA titers.
Conclusion: According to the above research, the rotavirus VP6-ferritin protein can be easily
express and self-assemble to the nano-vaccine and induce efficiency humoral and mucosal
immunity. Our research makes a foundation for the development of oral rotavirus vaccine.