Helicobacter pylori neutrophil activating protein's potential as tool in therapeutic immune modulation

Helicobacter pylori is one of the most common human pathogens and is associated with chronic gastritis, peptic ulcers and gastric carcinoma. H. pylori establishes a persistent infection, suggesting that the host response is ineffective in clearing the infection. H. pylori employs multiple mechanisms to undermine host responses. For example, CD4⁺ T cells are recruited to the gastric mucosa of infected individuals, but these cells are predominantly T helper 1 (T_H1) cells, which do not provide protection from the extracellular pathogen. H. pylori neutrophil-activating protein (HP-NAP) promotes the T_H1 polarized response. HP-NAP induces macrophages and dendritic cells to produce IL-12 and IL-23, which could explain the effect on T cells. These properties of HP-NAP make it a potential immunotherapeutic tool to redirect harmful T_H2 cell responses, as seen in atopic allergy, to T_H1 cell responses and also in IL-12 induction in cancer therapy.