Development and Evaluation of a Multi-Epitope Vaccine Based on P22 Virus-Like Particles Targeting Helicobacter pylori.

Abstract

Background: The current first-line treatment for Helicobacter pylori (H. pylori) infection is bismuth-based quadruple therapy. However, the widespread use of antibiotics has contributed to the emergence of antibiotic-resistant strains, thereby increasing the likelihood of treatment failure. This study aimed to develop a multi-epitope H. pylori vaccine, designated P22-C3, based on P22 Virus-like Particles, with the objective of reducing infection rates and preventing transmission.

Materials and methods: The structural characteristics of P22-C3 were analyzed using transmission electron microscopy (TEM) and dynamic light scattering (DLS). The safety profile of P22-C3 was evaluated through a series of in vitro and in vivo assays. In vitro assessments included cytotoxicity and proinflammatory factor testing. In vivo evaluations, conducted in immunized mice, involved monitoring changes in body weight, biochemical marker fluctuations, and histopathological examinations. The antibody response and T cell-mediated immunity elicited by P22-C3 were quantified using enzyme-linked immunosorbent assay (ELISA) and flow cytometry, respectively. Immune protection efficacy was assessed through a challenge experiment.

Results: P22-C3 successfully self-assembled into T = 7 icosahedral structures with an average diameter of 58 nm. Both in vitro and in vivo experiments confirmed that P22-C3 was safe and well-tolerated. Furthermore, P22-C3 elicited a dose-dependent IgG response and a mixed Th1/Th17 immune profile. In challenge experiments, mice immunized with P22-C3 demonstrated reduced bacterial loads and urease levels in the stomach.

Conclusion: P22-C3 was well-tolerated and successfully induced a strong immune response, offering protection against H. pylori infection. These properties make P22-C3 a promising H. pylori vaccine. It is important to note that this study was conducted solely in mice and did not involve human participants; therefore, a clinical trial registration number is not applicable.