Designing a broad-spectrum multi-epitope vaccine against human parainfluenza virus: an immunoinformatics approach

Objective Human parainfluenza virus type 3 (HPIV-3) is a key factor in global acquired respiratory infections, and there is no specific therapy available. Due to the complexity and variability of the pathogen antigen, the development of vaccines against HPIV-3 is lagging behind. It is crucial to design a novel broad-spectrum vaccine for comprehensive protection against continuously mutated wild-type strains.Methods To overcome the antigenic variation of the virus, we downloaded different HPIV-3 antigen proteins (F, M, N, and HN proteins) from NCBI and generated consensus sequences through sequence alignment. Furthermore, a broad-spectrum T cell epitope vaccine targeting HPIV-3 was predicted and designed via methods of reverse vaccinology.Results The multi-epitope vaccine (MEV) incorporated 11 cytotoxic T lymphocyte (CTL) epitopes (9-mer) and 11 helper T lymphocyte (HTL) epitopes (15-mer) from the F, M, N and HN proteins, being composed of 355 amino acid residues without adjuvant. The predicted T cell epitopes had solubility, no allergenicity, high antigenicity, and immunogenicity. The designed vaccine can effectively bind to Toll-like receptors in natural immunity, with good stability, hydrophilicity, and high population coverage.Conclusion The designed vaccine could be a candidate vaccine against HPIV-3 infection. We provide a novel immunoinformatics approach for vaccine design and development.