Homotypic Protection Against Rotavirus-Induced Diarrhea in Infant Mice Breast-Fed by Dams Immunized with the Recombinant VP8* Subunit of the VP4 Capsid Protein

The outer capsid proteins VP4 and VP7 induce neutralizing antibody against rotavirus. We have investigated in a mouse model the protection mediated by immunization with VP8*, the amino-terminal tryptic fragment of VP4. BALB/c female mice immunized with simian rotavirus SA11 VP6 and VP8* proteins expressed in Escherichia coli were mated with seronegative males. Litters were orally challenged with the SA11 strain (P5B[2], G3) or with the murine rotavirus strain EDIM (P10[16], G3) to verify the degree of protection against diarrhea induced in the newborns. Only those pups born to dams immunized with VP8* did not develop diarrhea after having been orally challenged with the SA11 strain. Pups bo…