Background:
Helicobacter pylori infection and its treatment still remains a challenge to human health
worldwide. A variety of antibiotics and combination therapies are currently used to treat H. pylori induced
ulcers and carcinoma; however, no effective treatment is available to eliminate the pathogen from the
body. Additionally, antibiotic resistance is also one of the main reasons for prolonged and persistent
infection.
Aim of the study:
Until new drugs are available for this infection, vaccinology seems the only
alternative opportunity to exploit against H. pylori induced diseases.
Methods: Multiple epitopes prioritized in our previous study have been tested for their possible antigenic
combinations, and results in 169-mer and 183-mer peptide vaccines containing the amino acid sequences
of 3 and 4 epitopes respectively, along with adjuvant (Cholera Toxin Subunit B adjuvant at 5’ end) and
linkers (GPGPG and EAAAK).
Results:
Poly-epitope proteins proposed as potential vaccine candidates against H. pylori include SabAHP0289-Omp16-VacA (SHOV), VacA-Omp16-HP0289-FecA (VOHF), VacA-Omp16-HP0289-SabA
(VOHS), VacA-Omp16-HP0289-BabA (VOHB), VacA-Omp16-HP0289-SabA-FecA (VOHSF), VacAOmp16-HP0289-SabA-BabA (VOHSB) and VacA-Omp16-HP0289-BabA-SabA (VOHBS). Structures of
these poly-epitope peptide vaccines have been modelled and checked for their affinity with HLA alleles
and receptors. These proposed poly-epitope vaccine candidates bind efficiently with A2, A3, B7 and DR1
superfamilies of HLA alleles. They can also form stable and significant interactions with Toll-like
receptor 2 and Toll-like receptor 4.
Conclusion:
Results suggest that these multi-epitopic vaccines can elicit a significant immune response
against H. pylori and can be tested further for efficient vaccine development.