Published online May 14, 2014. doi: 10.3748/wjg.v20.i18.5294
Revised: December 2, 2013
Accepted: January 6, 2014
Published online: May 14, 2014
Helicobacter pylori (H. pylori) neutrophil-activating protein (HP-NAP) was originally identified as a virulence factor of H. pylori for its ability to activate neutrophils to generate respiratory burst by releasing reactive oxygen species. Later on, HP-NAP was also found to be involved in the protection of H. pylori from DNA damage, supporting the survival of H. pylori under oxidative stress. This protein is highly conserved and expressed by virtually all clinical isolates of H. pylori. The majority of patients infected with H. pylori produced antibodies specific for HP-NAP, suggesting its important role in immunity. In addition to acting as a pathogenic factor by activating the innate immunity through a wide range of human leukocytes, including neutrophils, monocytes, and mast cells, HP-NAP also mediates adaptive immunity through the induction of T helper cell type I responses. The pro-inflammatory and immunomodulatory properties of HP-NAP not only make it play an important role in disease pathogenesis but also make it a potential candidate for clinical use. Even though there is no convincing evidence to link HP-NAP to a disease outcome, recent findings supporting the pathogenic role of HP-NAP will be reviewed. In addition, the potential clinical applications of HP-NAP in vaccine development, clinical diagnosis, and drug development will be discussed.
Core tip:Helicobacter pylori (H. pylori) neutrophil-activating protein (HP-NAP) acts as a virulence factor to play a pathogenic role in H. pylori infection. However, the unique immune properties and biological function of HP-NAP make it a potential candidate for clinical applications, including vaccine development, clinical diagnosis, and drug development.