Modulation of Antigen Display on PapMV Nanoparticles Influences Its Immunogenicity

Background: The papaya mosaic virus (PapMV) vaccine platform is a rod-shaped nanoparticle made of the recombinant PapMV coat protein (CP) self-assembled around noncoding single-stranded RNA (ssRNA) template. induces innate immunity through stimulation Toll-like receptors (TLR) 7 and 8. display antigen at surface nanoparticle, associated with co-stimulation signal via TLR7/8, ensures strong immune response, which ideal for development candidate vaccines. In this study, we assess impact where peptide fused, whether or extremities nanoparticles, on response directed to that antigen. Methods: Two different peptides from influenza A were used as model antigens. conserved M2e peptide, derived matrix 2 was chosen B-cell epitope, nucleocapsid cytotoxic T lymphocytes (CTL) epitope. These coupled two positions CP, N- (PapMV-N) C-terminus (PapMV-C), using transpeptidase activity Sortase (SrtA). responses, both humoral CD8+ T-cell-mediated, antigens in fusion contexts analyzed compared. coupling density also investigated. Conclusions: results demonstrate N-terminus CP led an enhanced compared C-terminus. difference between platforms linked capacity PapMV-N stimulate TLR7/8. We demonstrated strength increases nanoparticles.