Design of a novel multi-epitope monovalent vaccine against Hantaan virus using an immunoinformatics approach

Hantaan virus is a well-known causative agent of Hemorrhagic Fever with Renal Syndrome (HFRS) which is distributed broadly in the Eastern Asia, particularly in Korea, Russia, and China. Despite its significance, no FDA-approved vaccine currently exists for this virus. Therefore, this study aimed to design a novel multi-epitope monovalent vaccine against Hantaan virus utilizing an immunoinformatics approach, targeting the envelopment polyprotein and nucleoprotein. To develop potential candidate vaccines 6 CTL, 6 HTL, and 12 BCL epitopes were combined with suitable adjuvants, linkers and a PADRE sequence. V1 construct (MW: 39.2 kDa) is the best in length (373 aa), antigenic score (0.8426), and solubility (0.718) and it exhibits basic characteristics (Theoretical pI: 9.28), hydrophilic nature (GRAVY: -0.412), thermostability (Aliphatic index: 70.56), and significant stability (Instability index: 29.60). The secondary structure showed 20.38% alpha helix, 28.42% β sheet, and 44.24% random coil and the refined structure confirmed the validity. The vaccine could strongly interact with numerous MHC molecules and immune receptors of human, including DAF/CD55, integrins β 3 , gC1qR, and protocadherin-1 (PCDH1) and exhibited minimal deformability. The optimized CAI value was 0.986 having 50.491% GC content. Finally, the vaccine was inserted into the pET30a (+) vector for expression in E. coli strain K12 to assess microbial expression as well as translational potency. However, in vitro experiments using model organisms is essential for experimental validation.