Double-layered rotavirus-like particles are efficient carriers to elicit strong CTL responses to delivered heterologous antigens

•Rotavirus VLPs carrying large sequences in the inner space were produced.•Chimeric VLPs seem to be specifically endocyted by murine dendritic cells.•Mice were vaccinated with chimeric VLPs.•In vivo cytotoxic assays were used to evaluate cellular immune response.•A strong cytotoxic immune response was elicited against the heterologous sequence.

The first 92 amino acids of VP2 of rotavirus are dispensable for VLP assembly and can be replaced by heterologous reporter proteins without affecting either self-assembly of chimeric VP2 or the interaction with VP6 to render chimeric VP2/6 VLPs. In this study, we constructed recombinant baculoviruses expressing GFP or OVA fused to the amino terminus of a truncated VP2 sequence and produced chimeric VLPs by co-infection with a baculovirus expressing VP6. The results showed that these chimeric VLPs were efficiently uptaken by murine dendritic cells and that the heterologous sequences contained in the core of these VLPs seemed to be able to reach the MHC-I pathway as they elicited strong and specific CTL responses. Therefore, the data presented here suggest that chimeric VLPs could be used as excellent carriers to elicit CTL responses to antigens transported inside the VLPs.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide