Expression And Antigenicity Of Vp4 From Group A Human Rotavirus

Rotavirus (RV) belongs to Rotavirus genus in family Reoviridae. RV is the major etiology agents of acute gastroenteritis in human beings, mammals and birds. Vp4 is the outmost protein projected from the viral capsid, plays multiple important roles in virus infection, replication, immunity and is a target protein in exploiting rotavirus vaccines.In this study, Vp4 gene derived from a rotavirus TB-Chen strain which was isolated from a two years old patient with acute gastroenteritis was used to express recombinant protein. After PCR amplification, the Vp4 gene was cloned onto the expression vectors pET and a recombinant pET-Vp4 plasmid was constructed. The pET-Vp4 plasmid was further transformed into E. coli BL21(DE3) cell and recombinant protein Vp4 (rVp4) was highly expressed. Gel scanning analysis showed that the expressed protein account for about 17% of the total E. coli protein. Western Blot showed that rVp4 could be specifically recognized by guinea pig antibodies against Wa or SA11. After purification and renaturation rVP4 could form dimers. In immunofluorescent assay (IFA), anti-rVp4 antibodies recognize Vp4 protein in Wa- and SAil-infected MA104 cells at different infection time interval. IFA results showed that Vp4 expressed in Wa- and SAil-infected MA104 cells reached the peak level at 12 hours after infecton and, Vp4 protein distribute along the cell membrane and neuclear membrane. The results of neutralization test showed that the guinea pig antisbody against rVp4 could prevent MA104 cells from infection by SA11 or Wa.The results obtained in this study not only provided a solid basis for futher studying the fuction and immunity characteristics of Vp4 of group A rotavirus but also offered valuable data for study and development of rotavirus protein subunit vaccines.