In silico design of a multi-epitope vaccine against HPV16/18

Abstract

Background Cervical cancer is the fourth most common cancer affecting women and is caused by human Papillomavirus (HPV) infections that are sexually transmitted. There are currently commercially available prophylactic vaccines that have been shown to protect vaccinated individuals against HPV infections, however, these vaccines have no therapeutic effects for those who are previously infected with the virus. The current study’s aim was to use immunoinformatics to develop a multi-epitope vaccine with therapeutic potential against cervical cancer. Results In this study, T-cell epitopes from E5 and E7 proteins of HPV16/18 were predicted. These epitopes were evaluated and chosen based on their antigenicity, allergenicity, toxicity, and induction of IFN-γ production (only in helper T lymphocytes). Then, the selected epitopes were sequentially linked by appropriate linkers. In addition, a C-terminal fragment of Mycobacterium tuberculosis heat shock protein 70 (HSP70) was used as an adjuvant for the vaccine construct. The physicochemical parameters of the vaccine construct were acceptable. Furthermore, the vaccine was soluble, highly antigenic, and non-allergenic. The vaccine’s 3D model was predicted, and the structural improvement after refinement was confirmed using the Ramachandran plot and ProSA-web. The vaccine’s B-cell epitopes were predicted. Molecular docking analysis showed that the vaccine's refined 3D model had a strong interaction with the Toll-like receptor 4. The structural stability of the vaccine construct was confirmed by molecular dynamics simulation. Codon adaptation was performed in order to achieve efficient vaccine expression in Escherichia coli strain K12 (E. coli). Subsequently, in silico cloning of the multi-epitope vaccine was conducted into pET-28a ( +) expression vector. Conclusions According to the results of bioinformatics analyses, the multi-epitope vaccine is structurally stable, as well as a non-allergic and non-toxic antigen. However, in vitro and in vivo studies are needed to validate the vaccine’s efficacy and safety. If satisfactory results are obtained from in vitro and in vivo studies, the vaccine designed in this study may be effective as a therapeutic vaccine against cervical cancer.

Immunoinformatics applications in the development of therapeutic vaccines against human papillomavirus‐related infections and cervical cancer

“…81 Sanami et al in their studies of multi-epitope vaccine constructs for the treatment of HPV-associated cervical cancer sought to test both possibilities, the docking between the multiepitope and a cell surface protein, TLR4, 81 and between each epitope and its associated HLA macromolecule. 82 To perform molecular docking, it is initially necessary to have the structures modelled and then anchor them to each other. Thus, for ligands that were elaborated from structures already available in the Protein DataBank 93 it is possible to model by homology using the Modeller programme.…”

“…In addition, immunotherapy has given attention to new areas focused on the modulation of tumour microenvironments through receptors capable of inhibiting lymphocytes and the use of biomarkers in clinical trials. 69,81,82…”

“…Figure 2 demonstrates a possible flowchart with steps from the prediction of epitopes to the evaluation of the physicochemical properties, antigenicity, and allergenicity of the multi‐epitope. In addition to the steps mentioned in the figure, it is also possible to select and analyse epitopes based on the induction of interleukins and interferon, as was done in the multi‐epitope vaccine construction studies against HPV carried out by Sanami et al 81,82 . Further, it is important that all the data collected by in silico analysis be validated in vitro and in vivo to confirm the intended response 78 …”

“…Sanami et al. in their studies of multi‐epitope vaccine constructs for the treatment of HPV‐associated cervical cancer sought to test both possibilities, the docking between the multi‐epitope and a cell surface protein, TLR4, 81 and between each epitope and its associated HLA macromolecule 82 …”

Third-Generation Vaccines: Features of Nucleic Acid Vaccines and Strategies to Improve Their Efficiency

“…A study by Sanami et al included epitopes of HPV16 E6 and E7 oncoproteins in the construction that was suggested as an effective therapeutic vaccine after analysis of antigenicity, allergenicity, and physicochemical properties [ 37 ]. Another vaccine for the treatment of cervical cancer was designed with epitopes of HPV16/18 E5 and E7 proteins and showed stability, non-toxicity, and non-allergenicity [ 38 ]. Kumar et al [ 39 ] went further, designing a multi-epitope platform with prophylactic and therapeutic potential against HPV16 and 18 from peptides obtained from L1, E5, E6, and E7 proteins that can induce an immune response against CD8+ and TCD4+ lymphocytes.…”