Integration of Physicochemical Profiling and HLA Class II Binding for the Identification of Conserved Epitopes in the Glycoprotein of Lyssaviruses from Phylogroups I and II

Lyssaviruses are neurotropic viruses that cause fatal encephalitis, with the rabies virus as the most prominent member. The viral glycoprotein (G) plays a key role in infection and is the main target of adaptive immune responses. This study aimed to comparatively analyze linear B- and CD4+ T-cell epitopes in the G protein ectodomain of lyssaviruses from phylogroups I (RABV, EBLV-1, EBLV-2, DUVV, and ABLV) and II (LBV and MOKV) using bioinformatics tools. Protein sequences were obtained from GenBank, processed to isolate ectodomains, aligned for identity analysis, and used to generate consensus sequences. CD4+ T-cell epitopes were predicted based on HLA-II binding affinity, while linear B-cell epitopes were identified using physicochemical properties and assessed for N-glycan masking. Amino acid identity ranged from 76.71% to 83.79% in phylogroup I and 82.72% in phylogroup II. Phylogroup I showed a higher density of HLA-II epitopes (0.22) than phylogroup II (0.18). Despite differences in antigenicity distribution, conserved linear B-cell epitopes in both phylogroups overlapped with peptides binding to HLA-II DRB1*15:01 and were not masked by N-glycans. These findings highlight putatively conserved antigenic regions identified through computational analysis and may support future studies focused on the development of improved vaccines and immunoprophylactic strategies against lyssaviruses.