Inflammatory activation of neutrophils by Helicobacter pylori; a mechanism insensitive to pertussis toxin

• Published in: Clinical and experimental immunology 2001-01, Vol.123 (1), p.73-80
• Main Authors: Hansen, P. S., Madsen, P. H., Petersen, S. B., Nielsen, H.
• Format: Article
• Language: English
• Subjects: Bacterial diseases; Biological and medical sciences; Calcium Signaling - immunology; CD18 Antigens - biosynthesis; Cell Fractionation; Drug Resistance, Microbial; Ent and stomatologic bacterial diseases; Gastritis - immunology; Gastritis - microbiology; Gastritis - pathology; GTP-Binding Proteins - antagonists & inhibitors; GTP-Binding Proteins - metabolism; Helicobacter Infections - immunology; Helicobacter Infections - pathology; Helicobacter pylori; Helicobacter pylori - immunology; Human bacterial diseases; Humans; Immunity to Infection; Infectious diseases; Integrin alphaXbeta2 - biosynthesis; L-Selectin - biosynthesis; l‐selectin; Macrophage-1 Antigen - biosynthesis; Medical sciences; Neutrophil Activation - immunology; neutrophils; Neutrophils - immunology; Neutrophils - metabolism; Neutrophils - microbiology; Neutrophils - pathology; Pertussis Toxin; Sonication; Virulence Factors, Bordetella - toxicity; β2‐integrins
• ISSN: 0009-9104; 1365-2249
• DOI: 10.1046/j.1365-2249.2001.01368.x

Chronic active gastritis of the antral mucosa is a characteristic feature of infection with Helicobacter pylori and interactions between bacterial components and inflammatory cells are believed to play an important pathogenic role. Neutrophils stimulated with H. pylori sonicate were demonstrated to release l‐selectin (CD62L) expressed on the cellular surface, with a subsequent up‐regulation of the β2‐integrins CD11b and CD11c, both in a dose‐ and time‐dependent manner, reaching maximum levels after 45–60 min of stimulation. No changes were observed for the CD11a receptor upon stimulation. The activating properties of H. pylori sonicates on neutrophils were heat‐labile and susceptible to protease attack, indicating the protein nature of the activating factor. After size fractionation, the major neutrophil‐inducing activity was detected in the high molecular weight fraction exhibiting urease activity. Pertussis toxin was unable to inhibit neutrophil activation by the H. pylori protein(s). We conclude that proteins from H. pylori have a potent inflammatory effect on the surface membrane molecules CD62L, CD11b and CD11c essential for transendothelial migration of neutrophils to areas of inflammation. The neutrophil‐activating protein(s) act via a pertussis toxin‐insensitive mechanism.