B and T Cell Epitope-Based Peptides Predicted from Evolutionarily Conserved and Whole Protein Sequences of Ebola Virus as Vaccine Targets

Scand J Immunol. 2016 May;83(5):321-37. doi: 10.1111/sji.12425.

Abstract

Ebola virus (EBV) has become a serious threat to public health. Different approaches were applied to predict continuous and discontinuous B cell epitopes as well as T cell epitopes from the sequence-based and available three-dimensional structural analyses of each protein of EBV. Peptides '(79) VPSATKRWGFRSGVPP(94) ' from GP1 and '(515) LHYWTTQDEGAAIGLA(530) ' from GP2 of Ebola were found to be the consensus peptidic sequences predicted as linear B cell epitope of which the latter contains a region (519) TTQDEG(524) that fulfilled all the criteria of accessibility, hydrophilicity, flexibility and beta turn region for becoming an ideal B cell epitope. Different nonamers as T cell epitopes were obtained that interacted with different numbers of MHC class I and class II alleles with a binding affinity of <100 nm. Interestingly, these alleles also bound to the MHC class I alleles mostly prevalent in African and South Asian regions. Of these, 'LANETTQAL' and 'FLYDRLAST' nonamers were predicted to be the most potent T cell epitopes and they, respectively, interacted with eight and twelve class I alleles that covered 63.79% and 54.16% of world population, respectively. These nonamers were found to be the core sequences of 15mer peptides that interacted with the most common class II allele, HLA-DRB1*01:01. They were further validated for their binding to specific class I alleles using docking technique. Thus, these predicted epitopes may be used as vaccine targets against EBV and can be validated in model hosts to verify their efficacy as vaccine.

MeSH terms

  • Africa / epidemiology
  • Asia / epidemiology
  • Computational Biology
  • Computer Simulation
  • Conserved Sequence / genetics
  • Ebola Vaccines / immunology*
  • Ebolavirus / immunology*
  • Epitope Mapping*
  • Epitopes, B-Lymphocyte / genetics
  • Epitopes, B-Lymphocyte / immunology
  • Epitopes, B-Lymphocyte / metabolism*
  • Epitopes, T-Lymphocyte / genetics
  • Epitopes, T-Lymphocyte / immunology
  • Epitopes, T-Lymphocyte / metabolism*
  • Evolution, Molecular
  • Gene Frequency
  • HLA Antigens / genetics
  • HLA Antigens / metabolism
  • HLA-DRB1 Chains / metabolism
  • Hemorrhagic Fever, Ebola / epidemiology
  • Hemorrhagic Fever, Ebola / immunology
  • Hemorrhagic Fever, Ebola / prevention & control*
  • Humans
  • Protein Binding
  • Viral Envelope Proteins / immunology*

Substances

  • Ebola Vaccines
  • Epitopes, B-Lymphocyte
  • Epitopes, T-Lymphocyte
  • HLA Antigens
  • HLA-DRB1 Chains
  • HLA-DRB1*01:01 antigen
  • Viral Envelope Proteins
  • envelope glycoprotein, Ebola virus