Immunoinformatic Design and Structural Evaluation of a Full-Length mRNA Vaccine Targeting Rabies Glycoprotein G

Background/Objectives: Rabies remains a fatal viral disease, and current conventional vaccine strategies face significant challenges regarding structural stability and large-scale manufacturing. This study aimed to design a novel messenger ribonucleic acid (mRNA) vaccine candidate targeting the rabies virus glycoprotein G (RABV-G) using an integrated immunoinformatic and structural modeling framework. Methods: The RABV-G sequence was systematically evaluated for evolutionary conservation and safety, followed by 3D structural modeling. Highly antigenic B-cell and T-cell epitopes were identified based on human leukocyte antigen (HLA) binding, toxicity, and glycosylation shielding analyses. Functional interactions were assessed via molecular docking with the Toll-like Receptor 4/Myeloid Differentiation factor 2 (TLR4-MD2) complex. Finally, a full-length mRNA construct was engineered and computationally evaluated for translational efficiency, structural stability, and immune simulation. Results: The RABV-G target exhibited high evolutionary conservation, with 53.82% of positions fully identical and an additional 43.70% highly conserved (70–99%) across 87 analyzed sequences. Structural validation confirmed a high-quality model, enabling the extraction of accessible, non-glycosylated epitopes. Molecular docking simulations revealed a highly favorable predicted structural interaction with the TLR4-MD2 receptor, suggesting a potential structural capacity to engage innate immune pathways, pending experimental validation. The codon-optimized mRNA construct exhibited a predicted thermodynamically stable secondary structure (MFE = −429.50 kcal/mol) with an accessible translation initiation site, pending experimental validation. Furthermore, in silico immune simulations predicted a robust and sustained activation of both humoral and cellular immunity, notably including memory B-cell expansion. Conclusions: The computationally designed mRNA vaccine candidate demonstrates highly favorable structural characteristics and immunogenic potential. While these in silico findings present a promising foundational framework for rabies prevention, subsequent experimental laboratory validation is strictly required to confirm its functional efficacy and translation.