Role of lipopolysaccharide and related cytokines in Helicobacter pylori infection.
Recenti Prog Med
; 88(5): 237-41, 1997 May.
Article
em En
| MEDLINE
| ID: mdl-9200967
ABSTRACT
Helicobacter pylori is a gram-negative bacterium which accounts for the development of chronic gastritis and peptic ulcer in man. In this review, emphasis has been laid on the role of lipopolysaccharide (LPS) of the H. pylori cellular wall in the pathogenesis of gastroduodenal disease. H. pylori LPS exhibits a reduced endotoxic potency in terms of pyrogenicity, lethality, toxicity, mitogenicity, cytokine (CK) release and chromogenic limulus amebocyte lysate assay. This low biological activity of the LPS could be ascribed to the underacylation and underphosphorylation pattern of the lipid A backbone. However, also LPS core structures seem to contribute to the biological activity of the molecule. Despite this low immunological potential, an array of proinflammatory CKs are produced both in vitro and in vivo following stimulation of mucosal cells with H. pylori organisms. It is likely that LPS plays a major role in triggering interleukin (IL)-8, IL-1 and tumor necrosis factor-alpha production from both epithelial cells and macrophages. Finally, the lower immune response elicited by H. pylori LPS in comparison with other enterobacterial LPS may represent an escape mechanism from the host immunosurveillance exerted by this bacterium, thus allowing its survival and persistence in the gastric niche.
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Bases de dados:
MEDLINE
Assunto principal:
Lipopolissacarídeos
/
Citocinas
/
Helicobacter pylori
/
Infecções por Helicobacter
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Recenti Prog Med
Ano de publicação:
1997
Tipo de documento:
Article