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

Abstract

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 born to naive dams but foster nursed by VP8*-immunized dams did not develop diarrhea after having been orally infected with the SA11 strain, but they suffered diarrhea when challenged with the EDIM strain. These results support the concepts that (1) VP8* is a highly immunogenic polypeptide that induces effective homotypic protection against disease in pups born to dams immunized with this antigen and (2) in newborn mice the protection against disease is mediated by neutralizing secretory antibodies present in the milk rather than by serum antibodies transferred through the placenta to the offspring.

PROTECTIVE ACTIVITY STUDY OF A CANDIDATE VACCINE AGAINST ROTAVIRUS INFECTION BASED ON RECOMBINANT PROTEIN FliCVP6VP8

“…Полипептид внутреннего капсида VP6 является мажорным белком вириона, в экспериментах на лабораторных мышах показа-но, что он обеспечивает защиту новорожденных животных за счет индукции выработки нейтра-лизирующих секреторных антител у беременных самок [4]. Выбранный фрагмент VP6 в составе гибридного белка имеет общие и гомологичные участки с фрагментом белка VP6 ротавируса С, а также гомологичные участки с фрагментом бел-ка VP6 ротавируса В. Белок VP8 -N-концевой триптический фрагмент белка VP4 -является высокоиммуногенным полипептидом и индуци-рует эффективную защиту против заболевания.…”

Yeast expression of the VP8* fragment of the rotavirus spike protein and its use as immunogen in mice

“…PCR was performed using Expand High Fidelity (Roche) and plasmid pGEX-VP8 as template (Gil et al, 2000), leading to the synthesis of a 765-bp DNA fragment coding VP8* which was subcloned in pUC18 previously digested by HincII to give construction pVH. This DNA fragment was digested out by HindIII and subcloned in construction pIA1 (Andrés et al, 2003), consisting of the complete ICWP sequence including promoter and terminator in vector YEplac195, also digested by HindIII with the loss of 132 bp of the coding sequence of ICWP.…”

Screening and construction of probiotic strains with enhanced protective properties against intestinal disorders

“…This could best be achieved through mucosal routes (22). Previous reports demonstrated that the rotavirus outer capsid proteins VP7 and VP4, or its fragment VP8*, elicit the production of neutralizing antibodies (23,24). VP8* is a non-glycosylated protein of relatively small size (29.5 kDa) which was considered a suitable candidate for expression in LAB, with the aim of designing second-generation probiotic strains protective against rotavirus infections.…”