Virus-like particle vaccines for poliovirus types 1, 2, and 3 with enhanced thermostability expressed in insect cells.

Poliovirus (PV) is a pathogen that causes poliomyelitis, which may lead to paralysis and fatality. Inactivated PV vaccines (IPVs) and live-attenuated oral PV vaccines (OPVs) are currently used to defend against PV worldwide. Vaccines must be developed in a PV-free environment given the biosafety issues associated with OPV and IPV production and to eradicate PV globally. In this study, PV1, PV2, and PV3 virus-like particles with enhanced thermostability (PV-sVLPs) were produced in large quantities by using a baculovirus expression vector system (BEVS). Mice immunized with PV-sVLPs generated antibodies with strong PV-neutralizing response. In addition, splenocytes collected from immunized mice expressed high levels of IFN-γ, IL-2, GM-CSF, IL-5, and IL-10 upon PV-sVLPs stimulation. These data suggest that PV-sVLPs can serve as vaccines against PV infection.