[VP4 protein of simian rotavirus strain SA11 expressed by a baculovirus recombinant]

The complementary DNA copies of the gene 4 were prepared by reverse transcription and polymerase chain reaction (RT-PCR) from genomic RNA of simian rotavirus strain SA11. A complete VP4 gene was been inserted into a baculovirus intermediate vector pVL-1393 which was under control of the polyhedrin promoter. The outer capsid protein VP4 which was a major neutralization antigen of rotavirus, was expressed in high yield in Spodoptera frugiperda cell line. The VP4 protein expressed was recognized with a hyperimmunized serum directed against the rotavitus by immunoblot assay. Expressed VP4 protein own about 10 percent of the total proteins. The baculovirus recombinant expressed full-length VP4 protein was used to immunize animals. A high level of neutralizing antibody directed against parentalstrain SA11 virus was developed in the animals. The anti-vp4 antibody could block visible cytopathic effect (CPE) forming of SA11 virus in MA104 cells. Immunofluorescence test and Western blot also confirmed that the antibody could recognize specific antigen of rotavirus in infectious MA104 cells. The results suggest that VP4 protein expressed in a recombinant baculovirus has antigenicity and immunogenicity as well. It may be an important component in developing rotavirus recombinant and subunit vaccine.