H¢lic~baeter pylorl has I~en identified as a ¢~ttaati~ a=enl in ,ctiw chronic $astritis, The rec=ptor for this baeteri=t, however, is not known, It is likely that the r~wptor molecules may b~ 81yt:osphinsolipid~.* as shown in th~ ea~cs orother bacteria. We explored this po~sihility by a thin-layer chromatography (~LC).immun~staininu method. Amontt lllyeo~phinllolipids extracted from hum;tn gastric mucosa, intact t1¢11¢.oba¢l¢t pylorl Sl~.cifleall~, bound to PSO~.O~tleer trod IPNeuAc.LacCer. whereas no specific bindin8 to neutral tll~sphint~olipids, ,,vhiel~ sh~re the same ¢era mide muiety with P$Os-OalCer or ! PNeuAe. LacCer, was demonstrated, $onieated bacteria could still bind to I PNeoAoLacCer with comparable affinity. In contrast, the btndinll of bacteria to PSO~.GaiCer was 8reatly diminished upon sonieation, Th~se results suS$est that each of the olisosaeehar.ide moieties mr I PNeuAc-LacCcr and PSO,-GalCer may be spccitlcally recol]nized by difl'eren~ liljand molecule= of llelieaba¢ter i)~,'larLH¢lirc~harr¢r pylorl: Gastric mucosa: Glycosphinsolipid; Bacterial adhesion

The composition of the glycosphingolipids of the human gastrointestinal tract was studied. The major neutral glycosphingolipids were ceramide monohexosides (e.g., GalCer, GlcCer), LacCer, Gb3Cer, Gb4Cer and more polar ones with more than four sugars, whereas neither Gg3Cer nor Gg4Cer were present. The acidic glycosphingolipids consisted of sulfatides and gangliosides such as GM3, GM1, GD3 and GD1a. Also a large amount of sulfatides was found in the gastric mucosa and duodenum. The concentrations of sulfatides in the fundic mucosa, antral mucosa and duodenum amounted to 416.0, 933.8 and 682.9 nmol/g of dry weight, respectively, exceeding those in the gastric mucosa and kidney of other mammals. The major molecular species of the sulfatides were identified as I3SO3-GalCer with hydroxylated longer-chain fatty acids based on the analyses by gas-liquid chromatography and negative ion fast-atom bombardment mass spectrometry. In contrast, gangliosides in these regions showed a tendency to be lower than sulfatides, and the molar ratios of sulfatides to gangliosides were about 2.0, whereas those in other parts were less than 0.5. A high content of sulfatides in the gastric and duodenal mucosa, where mucosa is easily insulted by acid, pepsin and bile salts, may be closely related to their roles in mucosal protection.

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