Biomaterial Database

Pathogenic diversity of Helicobacter pylori. 1997

F Mégraud

Laboratoire de Bactériologie, Hôpital Pellegrin, Bordeaux, France.

Helicobacter pylori has been shown to possess a very heterogeneous genoma despite its common phenotypic properties. Some characteristics relevant to pathogenesis have also been found to be heterogeneous. This is the case for adherence properties and the amount of urease produced, but it was not possible to relate these properties to disease entities. A vacuolating cytotoxin which alters epithelial cells has been found in about 60% of strains isolated from patients with ulcers versus 30% from those with gastritis only. The cagA gene can be used as a marker to detect the cag pathogenicity island. This DNA fragment seems to induce an increased inflammation in the gastric tissue via release of interleukin 8 by the epithelial cells. The association of this marker is strongly linked with ulcers compared with gastritis only (80% vs 55%, respectively). A number of other properties may be heterogeneous, but the low number of strains studied does not allow conclusions to be drawn.

UI	MeSH Term	Description	Entries
D004269	DNA, Bacterial	Deoxyribonucleic acid that makes up the genetic material of bacteria.	Bacterial DNA
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000942	Antigens, Bacterial	Substances elaborated by bacteria that have antigenic activity.	Bacterial Antigen,Bacterial Antigens,Antigen, Bacterial
D001426	Bacterial Proteins	Proteins found in any species of bacterium.	Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial
D016480	Helicobacter pylori	A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus CAMPYLOBACTER, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus HELICOBACTER. It has been officially transferred to Helicobacter gen. nov. (see Int J Syst Bacteriol 1989 Oct;39(4):297-405).	Campylobacter pylori,Campylobacter pylori subsp. pylori,Campylobacter pyloridis,Helicobacter nemestrinae
D016481	Helicobacter Infections	Infections with organisms of the genus HELICOBACTER, particularly, in humans, HELICOBACTER PYLORI. The clinical manifestations are focused in the stomach, usually the gastric mucosa and antrum, and the upper duodenum. This infection plays a major role in the pathogenesis of type B gastritis and peptic ulcer disease.	Infections, Helicobacter,Helicobacter Infection,Infection, Helicobacter
D018375	Neutrophil Activation	The process in which the neutrophil is stimulated by diverse substances, resulting in degranulation and/or generation of reactive oxygen products, and culminating in the destruction of invading pathogens. The stimulatory substances, including opsonized particles, immune complexes, and chemotactic factors, bind to specific cell-surface receptors on the neutrophil.	Activation, Neutrophil,Activations, Neutrophil,Neutrophil Activations