How Can We Better Understand the Gastric Carcinogenesis of Helicobacter pylori?

M cells targeted H. pylori antigen SAM-FAdE displayed on bacterium-like particles induce protective immunity

BACKGROUND

Helicobacter pylori (H. pylori), a specific bacterium capable of surviving in the acidic environment of the stomach, has been recognized as a group of causative agents of gastric cancer. Therefore, the development of mucosal vaccines against H. pylori is expected to provide an important direction for the treatment of chronic gastritis and the prevention of gastric cancer.

METHODS AND RESULTS

In this study, we used bacteria-like particles (BLPs) obtained by treating Lactic acid bacteria (L. lactis) with hot acid, and successfully displayed the M cell-targeted H. pylori multi-epitope purified antigen SAM-FAdE, with 90% display efficiency. In addition, BLPs-SAM-FAdE can effectively target M ​​cell models and M cells of mouse Peyer's patches (PPs) through oral immunization, promote the transport of particulate vaccines to dendritic cells (BMDCs) and stimulate their maturation, significantly increased proportion of plasma cells and germinal centers B cells. This indicates that the vaccination can induce notable antigen-specific mucosal immune responses (production of sIgA), CD4+ T cell responses (Th1/Th2/Th17) and humoral immune responses (production of serum IgG). Furthermore, oral BLPs-SAM-FAdE dramatically reduced the H. pylori adhesion and specific 16S rRNA expression of H. pylori in gastric mucosal tissue, protecting gastric tissue from damage.

CONCLUSION

BLPs-SAM-FAdE can significantly reduce the adhesion of H. pylori in gastric mucosal tissue and inhibit gastritis and gastric damage caused by H. pylori infection.

Overcoming antibiotic resistance caused by genetic mutations of Helicobacter pylori with mucin adhesive polymer-based therapeutics

Herein, we describe the 3'-sialyllactose-polyethyleneimine-chlorine e6 conjugate (3PC), meticulously engineered to effectively target Helicobacter bacteria (H. pylori) within the gastric environment. The composition of 3PC comprises polyethyleneimine, a cationic polymer, 3'-sialyllactose, which exhibits a specific binding affinity for H. pylori surface proteins, and a photosensitizer capable of generating oxygen radicals in response to specific wavelengths. The distinctive feature of 3PC lies in its capacity to enhance interaction with the anionic mucus layer facilitated by electrostatic forces. This interaction results in prolonged residence within the intestinal environment. The extended vacation in the intestinal milieu overcomes inherent limitations that have historically impeded conventional antibiotics from efficiently reaching and targeting H. pylori. 3PC can be harnessed as a potent tool for antibacterial photodynamic therapy, and its versatility extends to addressing the challenges posed by various antibiotic-resistant strains. The exceptional efficacy of 3PC in enhancing intestinal residence time and eradicating H. pylori has been robustly substantiated in animal models, particularly in mice. In summary, 3PC is a formidable agent capable of eradicating H. pylori, irrespective of its antibiotic resistance status, by efficiently penetrating and selectively targeting the mucus layer within the gastric environment.