PT - JOURNAL ARTICLE AU - A Nøorgaard AU - L P Andersen AU - H Nielsen TI - Neutrophil degranulation by Helicobacter pylori proteins. AID - 10.1136/gut.36.3.354 DP - 1995 Mar 01 TA - Gut PG - 354--357 VI - 36 IP - 3 4099 - http://gut.bmj.com/content/36/3/354.short 4100 - http://gut.bmj.com/content/36/3/354.full SO - Gut1995 Mar 01; 36 AB - Mucosal biopsy specimens from patients with Helicobacter pylori infection in gastric antrum contain an increased amount of myeloperoxidase. This study was performed to elucidate the interaction of H pylori sonicate protein(s) and neutrophils concerning myeloperoxidase release. Neutrophil degranulation with myeloperoxidase release was examined in a direct stimulating assay. Priming activity of H pylori was examined after preincubating neutrophils in sonicate, either crude or modified by heat treatment, pronase inactivation and dialysis, and stimulating with N-formyl-methionyl-leucyl-phenylalanine (fMLP) or serum opzonised zymosan (OZ). It was found that H pylori sonicate protein(s) stimulates neutrophil degranulation with myeloperoxidase release in a concentration dependent way. The activity was distinct from fMLP and capable of priming the subsequent fMLP and OZ response. Experiments with the modified bacterial sonicate suggest the activity is caused by a protein, but the findings show that non-protein molecules, for example, lipopolysaccarides were also part of the H pylori sonicate priming activity. The increased mucosal myeloperoxidase in H pylori associated disease can be a direct consequence of bacteria derived stimulation of inflammatory neutrophils.