Epitope-driven common subunit vaccine design against H. pylori strains

Abstract

The developing potent vaccine is a pre-emptive strategy to tackle drug abuses and maladies of multidrug-resistant Helicobacter pylori strains. Ongoing vaccine studies are being conducted, however, development is in its infancy as ineffective vaccine targets might be. So, the linear perspective may indicate the need for potent subunit vaccine variants. Here, surface-exposed membrane proteins out of 826 common proteins of 53 H. pylori strains were chosen for analysis, as a follow-up to previous studies; these proteins are responsible for antigenicity to elicit the immune response. Antigenic determinant regions on prognostic targets were evaluated in the successive peptide screening using experimental T-cell epitope positive control and optimized with eminent immunoinformatics algorithms. In the milieu of docking, an ensemble of 2200 multiple conformers of complexes of modeled peptide and human leukocyte antigen- antigenD Related Beta-chain (HLA-DRB) was generated. Prioritized physics-based Molecular Mechanics-Generalized Born Surface Area approach coupled with bond length monitoring paved the improvement of prediction accuracy with binding potency estimations. ΔGbind free energy, interaction patterns, enrichment factor contributions and root-mean-square deviation predictions evidenced the existence of better binding affinities of four novel peptides hits with predominant allotype HLA-DR alleles than co-crystal controls. Moreover, conformational plasticity and stability assessments of the better ranked complex epitope-2 (86-FRRNPNINV-94) – HLA-DRB5*0101 formulated in dynamic simulations of 10,416 trajectories depicted stable interaction profile that correlated with docking endpoints. Thus, the proposed novel vaccine cocktails of the study would be ideal candidates and provide new insights for T-cell driven subunit vaccine design against H. pylori strainsCommunicated by Ramaswamy H. Sarma