Virus-like particles expressing Plasmodium berghei MSP-8 induce protection against P. berghei infection

[[[ Aims: ]]] Merozoite surface protein 8 (MSP-8) of Plasmodium parasites plays an important role in erythrocyte invasion and is a potential malaria vaccine candidate. [[[ Methods and results: ]]] In this study, virus-like particles (VLPs) expressing MSP-8 of Plasmodium berghei on the surface of influenza virus matrix protein 1 (M1) core protein were generated for vaccine efficacy assessment. Mice were intramuscularly (IM) immunized with MSP-8 VLPs twice and challenge-infected with P. berghei. We found that VLP vaccination elicited higher levels of P. berghei-specific IgG antibody response in the sera, along with blood CD4^{+} and CD8^{+} T-cell response enhancement compared to the naïve control mice. CD4^{+} and CD8^{+} effector memory T-cell and memory B-cell responses in the spleen were found to be higher in VLP-immunized mice compared to control mice. VLP vaccination significantly reduced inflammatory cytokine (IFN-γ) response in the spleen and parasitemia levels in blood compared to naïve control mice. [[[ Conclusions: ]]] These results indicate that MSP-8 containing virus-like particles could be a vaccine candidate for blood-stage vaccine design.