Recombinant Japanese Encephalitis Virus Envelope Antigen Presented on CoPoP Liposomes Elicits Cellular Immunity and Protects Mice From Lethal Challenge

T-cell IFN-γ responses alongside functional neutralizing Abs. In a stringent intracerebral lethal challenge model, rJEV-E/ECLSQ conferred robust protection despite moderate 50% plaque reduction neutralization test titers. JEV-specific IgG responses were sustained for at least one year, with recallable cellular immunity upon late boosting. These findings demonstrate that CoPoP-based particleization enables qualitative modulation of vaccine-induced immunity while maintaining effective protection in a stringent challenge setting.