An immunoinformatics-driven multiepitope subunit vaccine targeting Oropouche virus: Molecular docking, immune and dynamics simulation approaches.

The Oropouche virus (OROV) is an emerging zoonotic orthobunyavirus responsible for recurring outbreaks of febrile illness and neurological disorders in South and Central America. Despite its growing public health issues, no FDA-approved vaccines or antiviral therapies currently exist. To address this gap, a multiepitope subunit vaccine was designed to target OROV glycoproteins G1 (Gn), G2 (Gc), and the nucleocapsid (N) protein using a reverse-vaccinology (RV) approach. For vaccine construction, suitable epitopes (MHC-I, MHC-II, and linear B-cell) were selected based on percentile rank, antigenicity, allergenicity, and toxicity. However, the biophysical attributes demonstrated advantageous characteristics, including stability and solubility (GRAVY score: -0.432). The structural modelling exhibited a Ramachandran and Z scores of 91.86% (most favoured regions) and -1.81, respectively. However, the molecular docking with TLR-2 and TLR-4 receptors showed probable interactions (-1126.8 kJ/mol) and (-1239.4 kJ/mol), respectively. Moreover, dynamics simulation of the vaccine and Vaccine-TLR-4 complexes confirmed probable dynamic stability and compactness. The codon optimisation for Escherichia coli K12 expression yielded a CAI value of 1.0 and a GC content of (30-70) %, indicating optimal expression. The immune simulation predicted strong antibody-mediated and T cell-mediated immunity, including elevated IFN-γ, IgG, and memory cell populations. These findings suggest the potential of multiepitope subunit vaccines as a promising preventive candidate against OROV. However, additional experimental verification is required to confirm its immunogenicity and safety in experimental settings.