In-silico design and evaluation of a novel mRNA vaccine against human bocavirus 1: A neglected viral pathogen.

Human Bocavirus 1 (HBoV1) majorly affects infants and children, resulting severe lower respiratory tract infections. Since its first identification in 2005, HBoV1 has been detected in up to 18 % of respiratory infection cases, with a chronicity rate ranging from 2 % to 19 % in pediatric populations. Despite its considerable clinical impact, no specific vaccines or targeted therapies are currently available. This study aimed to design a chimera vaccine via reverse vaccinology and immunoinformatics approaches. T-cell and B-cell epitopes were derived and subsequently screened for non-allergenicity, antigenicity, non-toxicity, and the ability to induce a robust immune response. A multi-epitope vaccine (MEV) construct was designed, incorporating linear B-cell epitopes (LBLs), cytotoxic T-lymphocyte (CTL) epitopes, and helper T-lymphocyte (HTL) epitopes, connected via flexible and rigid linkers, along with adjuvants to enhance immune response. Molecular docking and molecular dynamics (MD) simulations, including analyses such as RMSD, RMSF, principal component analysis (PCA), radius of gyration (Rg), MM-PBSA binding free energy, solvent-accessible surface area (SASA), dynamic cross-correlation matrix (DCCM), and normal mode analysis (NMA), were performed to check the stability and binding affinity of the MEV with human Toll-like receptor 4 (TLR4) and TLR2. These simulations confirmed the complex's structural stability and its favorable interaction potential, suggesting that the vaccine could trigger an effective immune response. Computational immune simulations demonstrated that the vaccine might elicit robust and sustained immune responses. Additionally, codon-optimized sequences were utilized to design mRNA-based vaccines, to ensure enhanced translational efficiency. In-silico cloning indicated the feasibility of recombinant expression in Escherichia coli strain K12. This study presents the computational design of a chimeric vaccine candidate targeting HBoV1 using an integrated reverse vaccinology and immunoinformatics approach. While the in-silico results are promising, further experimental validation through in-vitro and in-vivo studies are essential to affirm its real-world applicability.