Design of a Multiepitope Pan-Proteomic mRNA Vaccine Construct Against African Swine Fever Virus: A Reverse Vaccinology Approach.

Abstract

African swine fever (ASF), caused by African swine fever virus (ASFV), is a highly contagious disease with devastating effects on the global pig industry. This warrants the development of effective control strategies, such as vaccines. However, previously developed inactivated vaccines have proven ineffective, while live-attenuated vaccines carry inherent safety risks. The use of mRNA vaccines eliminates these risks offering a safe, cost-effective, and efficient vaccine strategy against ASFV. In this study, a reverse vaccinology approach was used to design a multiepitope pan-proteomic mRNA vaccine against ASFV. Various bioinformatics tools were employed to predict epitopes for cytotoxic T lymphocytes, helper T lymphocytes, and B lymphocytes. A 50S ribosomal L7/L12 protein adjuvant, 5' cap, poly(A) tail, signal peptide, and MHC-I-targeting domain were incorporated into the design using appropriate linkers to increase immunogenicity, stability, and recognition efficiency. The physicochemical properties of the final construct were evaluated, and docking analyses were done with Toll-like receptors (TLRs) 3, 4, and 7 to evaluate binding affinity. A molecular dynamics simulation was then performed to determine binding stability, while immune simulations evaluated host's immune response. Based on 100 ASFV proteomes, six epitopes that induce cytotoxic T-cell responses, five epitopes that induce helper T-cell responses, and four epitopes that induce antibody production were predicted. The designed vaccine construct was found to be nonallergenic, antigenic, and stable when bound to TLR4 while the binding pocket analyses of the vaccine construct to TLR3 and TLR7 indicate high translation efficiency. Immune simulations demonstrated successful induction of immune responses and generation of antigen-specific memory cells. In conclusion, this study introduces an mRNA vaccine construct as a potential disease control strategy against ASF for in vitro confirmation.