Lactotetraosylceramide, a Novel Glycosphingolipid Receptor for Helicobacter pylori, Present in Human Gastric Epithelium

Abstract

The binding of Helicobacter pylori to glycosphingolipids was examined by binding of 35 S-labeled bacteria to glycosphingolipids on thin-layer chromatograms. In addition to previously reported binding specificities, a selective binding to a non-acid tetraglycosylceramide of human meconium was found. This H. pylori binding glycosphingolipid was isolated and, on the basis of mass spectrometry, proton NMR spectroscopy, and degradation studies, were identified as Gal␤3GlcNAc␤3-Gal␤4Glc␤1Cer (lactotetraosylceramide). When using non-acid glycosphingolipid preparations from human gastric epithelial cells, an identical binding of H. pylori to the tetraglycosylceramide interval was obtained in one of seven samples. Evidence for the presence of lactotetraosylceramide in the binding-active interval was obtained by proton NMR spectroscopy of intact glycosphingolipids and by gas chromatography-electron ionization mass spectrometry of permethylated tetrasaccharides obtained by ceramide glycanase hydrolysis. The lactotetraosylceramide binding property was detected in 65 of 74 H. pylori isolates (88%). Binding of H. pylori to lactotetraosylceramide on thin-layer chromatograms was inhibited by preincubation with lactotetraose but not with lactose. Removal of the terminal galactose of lactotetraosylceramide by galactosidase hydrolysis abolished the binding as did hydrazinolysis of the acetamido group of the Nacetylglucosamine. Therefore, Gal␤3GlcNAc is an essential part of the binding epitope.Adhesion of microorganisms to target cells is regarded as a first step in pathogenesis of infections, where the specificity of the adhesins of the infectious agent on the one hand and the receptor structures expressed by the epithelial cells of the host target organ on the other are important determinants of the host range and the tissue tropism of the pathogen (1).The human gastric pathogen Helicobacter pylori is an etiologic agent of chronic active gastritis, peptic ulcer disease, and gastric adenocarcinoma (2, 3). This Gram-negative bacterium has a very distinct host range and tissue tropism, i.e. it requires human gastric epithelium for colonization (4). In the human stomach most of the bacteria are found in the mucus layer (5), but selective association of the bacteria to surface mucous cells has also been shown (4, 6).Several different binding specificities of H. pylori have previously been demonstrated. Thus, the binding of the bacterium to such diverse compounds as phosphatidylethanolamine and gangliotetraosylceramide (7), the Le b blood group determinant (8), heparan sulfate (9), the GM3 1 ganglioside and sulfatide (10, 11), and lactosylceramide (12), has been reported. A sialic aciddependent binding of H. pylori to large complex glycosphingolipids (polyglycosylceramides) has also been documented (13). However, only one H. pylori adhesin, the Le b binding BabA adhesin, has been identified to date (14).In the present study a number of different H. pylori strains were labeled with [35 S]methionine and examined for binding to a panel of...

Helicobacter pylori and Complex Gangliosides

“…Thus, d18:1 designates sphingosine [1,3-dihydroxy-2-aminooctadecene] and t18:0 designates phytosphingosine [1,3,4-trihydroxy-2-aminooctadecane].) Other receptors subsequently reported include gangliotetraosylceramide (17), the Le b antigen (3), NeuAc␣3-neolactotetraosylceramide (20), lactosylceramide (1), and lactotetraosylceramide (38). In a separate series of studies, the binding of H. pylori to sialic acid-containing glycoconjugates from a variety of origins was demonstrated (21,22).…”

Novel Binding Epitope for Helicobacter pylori Found in Neolacto Carbohydrate Chains

“…Like many other microbes, H. pylori recognizes carbohydrates, probably mediating essential attachment to host cells (4,5). However, H. pylori is unusually complex in its binding to carbohydrates as shown by interaction with sialylated oligosaccharides (6), gangliotetraosylceramide (7), Lewis b antigen (8), monohexosylceramide (9), lactosylceramide (10), lactotetraosylceramide (11), sulfatide (12), and heparan sulfate (13). The inhibition of binding of H. pylori to gastric cells by glycoconjugates (14) and free oligosaccharides (15) has been reported, and sialyllactose was shown to eradicate bacteria or decrease bacterial density in rhesus monkeys experimentally infected with H. pylori (16).…”

Relapsing fever Borrelia binds to neolacto glycans and mediates rosetting of human erythrocytes

“…Neolactotetraosylceramide has been described in several human tissues, such as erythrocytes (15), neutrophils (14), brain (19), stomach (10), and semen (20). This broad tissue distribution stands in sharp contrast to the distribution of lactotetraosylceramide, which only has been chemically identified in the human gastrointestinal tract (10,21).…”

“…Binding of radiolabeled Borrelia to GSLs on thin-layer chromatograms was performed as described (10). Mixtures of GSLs (40 g/lane) or pure compounds (1-4 g/lane) were separated on aluminum-backed silica gel plates.…”