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PubMed · 1384604

Vitronectin binding by Helicobacter pylori.

M Ringnér·M Paulsson·T Wadström
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Abstract

Vitronectin, a serum and extracellular matrix protein involved in immunological reactions, interacts with Helicobacter pylori strains. Of the 20 H. pylori strains tested three strains bound more than 50% of the vitronectin added, five strains bound 25-40%, nine strains bound 10-20% and three strains bound 5-8% vitronectin. Two strains, one with high- and one with low-binding properties, were selected for further characterization of 125I-vitronectin binding. Binding to the urea-activated 125I-labelled vitronectin was fast, saturable and reversible when an excess of unlabelled vitronectin was added to the bacteria with bound 125I-vitronectin. The binding was heat- and protease-sensitive, suggesting that the binding was mediated by bacterial cell-surface proteins. Since components such as fetuin and orosomucoid but not asialofetuin inhibited the binding, sialic-acid specific proteins, related to H. pylori sialic-acid specific haemagglutinins, were probably involved.

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Blood ProteinsExtracellular Matrix ProteinsGlycoproteinsHelicobacter pyloriHydrogen-Ion ConcentrationRadioligand AssayUreaVitronectinJournal ArticleResearch Support, Non-U.S. Gov't

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M Ringnér, M Paulsson, T Wadström. 1992. Vitronectin binding by Helicobacter pylori.. https://doi.org/10.1111/j.1574-6968.1992.tb05904.x

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