Designing a next-generation multi-stage vaccine for malaria prevention.

Malaria is a potentially fatal parasitic disease that significantly affects human health worldwide. Several drugs are available for malaria treatment, but an alarming increase in Plasmodium drug resistance is of huge concern. To date, only two vaccines, RTS,S/AS01 and R21/Matrix-M, are recommended by the WHO. The present study focuses on designing a multi-epitope subunit vaccine targeting five key Plasmodium proteins using an immunoinformatic approach. Three vaccine constructs comprising adjuvants, cytotoxic T-lymphocyte-binding epitopes, helper T-lymphocyte-binding epitopes, B-cell epitopes, and specific linkers were designed. The assessment of their physicochemical properties revealed that the constructs were antigenic, non-allergenic, and non-toxic. The vaccines' 3D structures were designed, refined, and validated. Molecular docking with the immune receptor TLR-4 revealed the most stable binding to construct 1. The molecular dynamics simulations of the complex with construct 1 revealed strong, stable interactions. The vaccine candidate was evaluated through immune simulations to predict its immunogenic profile. In silico cloning indicated its potential for efficient expression in E. coli. The proposed vaccine construct has shown promising results; however, in vitro and in vivo studies are necessary to validate its efficacy.