Immunoinformatics-based characterization of immunogenic CD8 T-cell epitopes for a broad-spectrum cell-mediated...

Human papillomavirus (HPV) represents the most prevalent sexually transmitted infectious agent worldwide. Vaccination has been an approach successfully used as a prophylactic measure against this infectious agent in patients without previous contact with the genotypes present in the vaccine. In this work, we use a computational approach to predict CD8 T cell epitopes from HPV proteins to promote cell-mediated immunity. We evaluated immunogenicity, conservation, toxicity, stability and population coverage of epitopes. Finally, a molecular docking analysis was performed to confirm the stability of the complexes formed. We identified 17 epitopes with affinity for several HLA alleles, covering 5 binding supermotifs (A2, A3, A24, B62 and B57). The analyses showed that these epitopes have a high population coverage and are highly conserved among several HPV genotypes. Seven of them (NWKNFFSTTW_E1594-603, KVSAFQYRVFRV_L163-74, LQFIFQLCK_L1372-380, RVFRVQLPDPNK_L170-81, FNKPYWLHR_L1307-315, FITCVDTTR_L1330-338 and HLRREQIFAR_L1248-257) were 100% conserved. Finally, molecular docking confirmed the stability of the complexes by means of a large network of hydrogen bonds formed and the calculated low bonding energy. The epitopes identified in this study are potential candidates as components of therapeutic vaccines and we suggest that these epitopes can be used in future studies aiming to activate antigen-specific CD8 T cells.