Bioinformatics and immunoinformatic approaches for structural modeling and vaccine design of the CCHFV whole genome to develop a novel broad-spectrum multiepitope vaccine candidate.

Crimean-Congo hemorrhagic fever virus (CCHFV), the causative agent of Crimean-Congo hemorrhagic fever (CCHF), represents the most widely distributed tick-borne viral disease in humans and is currently managed only through supportive care. Consequently, considerable efforts have been directed toward the development of an effective vaccine to control this pathogen. Here, we report the first comprehensive in silico prediction of immunogenic CD8⁺ T cells, CD4⁺ T cells, and B-cell epitopes across the S, M, and L segments of CCHFV. Candidate epitopes were evaluated for conservation in mouse and human homologs of HLA alleles, as well as for antigenicity, toxicity, sequence homology, cellular topology, and binding affinity to a broad range of human leukocyte antigen (HLA) alleles. The final multiepitope vaccine construct was assembled by linking selected epitopes with an adjuvant via KK, AAY, and GPGPG linkers. Codon optimization and in silico cloning into prokaryotic and eukaryotic expression vectors confirmed high-level expression potential in Escherichia coli and human cells. Molecular docking analyses demonstrated that the vaccine-derived epitopes bind HLA molecules with affinities comparable to those of naturally processed peptides. Molecular dynamics simulations further revealed stable and robust interactions between the vaccine construct and Toll-like receptors (TLRs) throughout the simulation period, indicating the potential to elicit strong immune activation upon administration. The designed vaccine is predicted to stimulate both humoral and cellular immunity effectively. Although the construct exhibits promising immunogenicity, safety, and stability in silico, experimental validation in appropriate model systems is warranted to substantiate these findings.