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  • 1. Fagerberg, David
    et al.
    Angström, Jonas
    Halim, Adnan
    Hultberg, Anna
    Rakhimova, Lena
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Hammarström, Lennart
    Borén, Thomas
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Teneberg, Susann
    Novel Leb-like Helicobacter pylori-binding glycosphingolipid created by the expression of human alpha-1,3/4-fucosyltransferase in FVB/N mouse stomach.2009Ingår i: Glycobiology, ISSN 0959-6658, E-ISSN 1460-2423, Vol. 19, nr 2, s. 182-191Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The "Le(b) mouse" was established as a model for investigations of the molecular events following Le(b)-mediated adhesion of Helicobacter pylori to the gastric epithelium. By the expression of a human alpha-1,3/4-fucosyltransferase in the gastric pit cell lineage of FVB/N transgenic mice, a production of Le(b) glycoproteins in gastric pit and surface mucous cells was obtained in this "Le(b) mouse," as demonstrated by binding of monoclonal anti-Le(b) antibodies. To explore the effects of the human alpha-1,3/4-fucosyltransferase on glycosphingolipid structures, neutral glycosphingolipids were isolated from stomachs of transgenic alpha-1,3/4-fucosyltransferase-expressing mice. A glycosphingolipid recognized by BabA-expressing H. pylori was isolated and characterized by mass spectrometry and proton NMR as Fuc alpha 2Gal beta 3(Fuc alpha 4)GalNAc beta 4 Gal beta 4 Glc beta 1Cer, i.e., a novel Le(b)-like glycosphingolipid on a ganglio core. In addition, two other novel glycosphingolipids were isolated from the mouse stomach epithelium that were found to be nonbinding with regard to H. pylori. The first was a pentaglycosylceramide, GalNAc beta 3 Gal alpha 3(Fuc alpha 2)Gal beta 4 Glc beta 1Cer, in which the isoglobotetrasaccharide has been combined with Fuc alpha 2 to yield an isoglobotetraosylceramide with an internal blood group B determinant. The second one was an elongated fucosyl-gangliotetraosylceramide, GalNAc beta 3(Fuc alpha 2)Gal beta 3GalNAc beta 4Gal beta 4 Glc beta 1Cer.

  • 2. Ito, Yuki
    et al.
    Vela, Jose Luis
    Matsumura, Fumiko
    Hoshino, Hitomi
    Lee, Heeseob
    Kobayashi, Motohiro
    Bao, Xingfeng
    Boren, Thomas
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Jin, Rongsheng
    Seeberger, Peter H.
    Nakayama, Jun
    Kronenberg, Mitchell
    Fukuda, Minoru
    Immunological functions of cholesteryl alpha-glucosides in helicobacter pylori-associated inflammation2011Ingår i: Glycobiology, ISSN 0959-6658, E-ISSN 1460-2423, Vol. 21, nr 11, s. 1485-1486Artikel i tidskrift (Refereegranskat)
  • 3. Ito, Yuki
    et al.
    Vela, Jose Luis
    Matsumura, Fumiko
    Hoshino, Hitomi
    Tyznik, Aaron
    Lee, Heeseob
    Girardi, Enrico
    Zajonc, Dirk M.
    Kobayashi, Motohiro
    Bao, Xingfeng
    Boren, Thomas
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Jin, Rongsheng
    Seeberger, Peter H.
    Nakayama, Jun
    Kronenberg, Mitchell
    Fukuda, Minoru
    Helicobacter pylori cholesteryl alpha-glucosides are critical for bacterial growthand activation of invariant NKT cells2012Ingår i: Glycobiology, ISSN 0959-6658, E-ISSN 1460-2423, Vol. 22, nr 11, s. 1635-1636Artikel i tidskrift (Övrigt vetenskapligt)
  • 4. Li, Chunxia
    et al.
    Palma, Angelina S.
    Zhang, Pengtao
    Zhang, Yibing
    Gao, Chao
    Silva, Lisete M.
    Li, Zhen
    Trovão, Filipa
    Weishaupt, Markus
    Seeberger, Peter H.
    Likhosherstov, Leonid M.
    Piskarev, Vladimir
    Yu, Jin
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Westerlind, Ulrika
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Chai, Wengang
    Noncovalent microarrays from synthetic amino-terminating glycans: Implications in expanding glycan microarray diversity and platform comparison2021Ingår i: Glycobiology, ISSN 0959-6658, E-ISSN 1460-2423, Vol. 31, nr 8, s. 931-946Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Glycan microarrays have played important roles in detection and specificity assignment of glycan recognition by proteins. However, the size and diversity of glycan libraries in current microarray systems are small compared to estimated glycomes, and these may lead to missed detection or incomplete assignment. For microarray construction, covalent and noncovalent immobilization are the two types of methods used, but a direct comparison of results from the two platforms is required. Here we develop a chemical strategy to prepare lipid-linked probes from both naturally derived aldehyde-terminating and synthetic amino-terminating glycans that addresses the two aspects: expansion of sequence-defined glycan libraries and comparison of the two platforms. We demonstrate the specific recognition by plant and mammalian lectins, carbohydrate-binding modules and antibodies and the overall similarities from the two platforms. Our results provide new knowledge on unique glycan-binding specificities for the immune receptor Dectin-1 toward beta-glucans and the interaction of rotavirus P[19] adhesive protein with mucin O-glycan cores.

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  • 5. Löfling, Jonas
    et al.
    Diswall, Mette
    Eriksson, Sara
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Borén, Thomas
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Breimer, Michael E
    Holgersson, Jan
    Studies of Lewis antigens and H. pylori adhesion in CHO cell lines engineered to express Lewis b determinants2008Ingår i: Glycobiology, ISSN 0959-6658, E-ISSN 1460-2423, Vol. 18, nr 7, s. 494-501Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many microbes bind and adhere via adhesins to host cell carbohydrates as an initial step for infection. Therefore, cell lines expressing Lewis b (Le(b)) determinants were generated as a potential model system for Helicobacter pylori colonization and infection, and their expression of blood group Lewis determinants was characterized. CHO-K1 cells were stably transfected with selected glycosyltransferase cDNAs, and two Le(b) positive clones, 1C5 and 2C2, were identified. Expression of Lewis (Le(a), Le(b), Le(x), and Le(y)) determinants was analyzed by flow cytometry of intact cells, SDS-PAGE/Western blot of solubilized glycoproteins, and thin layer chromatography immunostaining of isolated glycolipids (GL). Binding of H. pylori to cells was examined by microscopy and quantified. Flow cytometry showed that 1C5 and 2C2 were Le(a) and Le(b) positive. 1C5 expressed Le(b) on O-linked, but not N-linked, glycans and only weakly on GLs. In contrast, 2C2 expressed Le(b) on N-, O-glycans, and GLs. Furthermore, both clones expressed Le(a) on N- and O-glycans but not on GLs. 2C2, but not 1C5, stained positively for Le(y) on N-linked glycans and GLs. Both clones, as well as the parental CHO-K1 cells, expressed Le(x) on GLs. A Le(b)-binding H. pylori strain bound to the 1C5 and 2C2 cells. In summary, two glycosyltransferase transfected CHO-K1 cell clones differed regarding Lewis antigen expression on N- and O-linked glycans as well as on GLs. Both clones examined supported adhesion of a Le(b)-binding H. pylori strain and may thus be a useful in vitro model system for H. pylori colonization/infection studies.

  • 6. Magalhaes, Ana
    et al.
    Marcos-Pinto, Ricardo
    Gomes, Joana
    Nairn, Alison V.
    Rossez, Yannick
    Robbe-Masselot, Catherine
    Maes, Emmanuel
    Bugaytsova, Zhanna
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Figueiredo, Ceu
    Borén, Thomas
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Moremen, Kelley W.
    Reis, Celso A.
    The glycan receptors of Helicobacter pylori: decoding the pathways underlying gastric glycophenotype modulation2016Ingår i: Glycobiology, ISSN 0959-6658, E-ISSN 1460-2423, Vol. 26, nr 12, s. 1401-1402Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The gastrointestinal tract is covered by a complex extracellular mucus layer that protects the gastric epithelium fromexternal aggressions such as chemical agents, microorganismsand shear stress. Although this mucus barrier confers protec-tion against certain pathogens, it may also provide a niche formicrobial binding.Helicobacter pyloriexploits the host glycoconjugates present in the gastric mucus layer and lining thesurface epithelium of the gastric mucosa to colonize the stomach. Infection can persist for decades promoting chronicinflammation, and in a subset of individuals lesions cansilently progress to cancer. The secreted MUC5AC mucin isthe main component of the gastric mucus layer, andH. pyloriBabA-mediated binding to MUC5AC confers increased riskfor overt disease. We have shown that FUT2 determines theO-glycosylation pattern of Muc5ac, with Fut2 knock-outleading to a marked decrease inα1,2-fucosylated structuresand increased expression of the terminal type 1 glycan structure Lewisa. Importantly, for thefirst time, we structurallyvalidated the expression of Lewisain murine gastric mucosa(1). We further demonstrated that loss of mucin FUT2-mediated fucosylation impairs gastric mucosal binding ofH.pyloriBabA adhesin, which is a recognized feature of patho-genicity. UponH. pyloriinfection,concomitantly with tissueinflammation, there is a remodeling of the gastric glycopheno-type. We showed that increased expression of sialyl-Lewisa/xantigens is due to transcriptional up-regulation of theB3GNT5,B3GALT5,andFUT3genes. In addition, weobserved thatH. pyloriinfected individuals present a markedgastric local pro-inflammatory signature with significantlyhigher TNF-αlevels and demonstrated that TNF-induced activation of the NF-kappaB pathway results in B3GNT5 up-regulation (2). Furthermore, we showed that this gastric glycosylation shift, characterized by increased sialylation pat-terns, favors SabA-mediatedH. pyloriattachment to humaninflamed gastric mucosa. Our data provides clinically relevantinsights into the regulatory mechanisms underlyingH. pylorimodulation of host glycosylation machinery, and phenotypicalterations crucial for life-long infection and gastric disease.

  • 7. Magalhães, Ana
    et al.
    Gomes, Joana
    Ismail, Mohd Nazri
    Haslam, Stuart M
    Mendes, Nuno
    Osório, Hugo
    David, Leonor
    Le Pendu, Jacques
    Haas, Rainer
    Dell, Anne
    Borén, Thomas
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Reis, Celso A
    Fut2-null mice display an altered glycosylation profile and impaired BabA-mediated Helicobacter pylori adhesion to gastric mucosa2009Ingår i: Glycobiology, ISSN 0959-6658, E-ISSN 1460-2423, Vol. 19, nr 12, s. 1525-1536Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Glycoconjugates expressed on gastric mucosa play a crucial role in host-pathogen interactions. The FUT2 enzyme catalyzes the addition of terminal alpha(1,2)fucose residues, producing the H type 1 structure expressed on the surface of epithelial cells and in mucosal secretions of secretor individuals. Inactivating mutations in the human FUT2 gene are associated with reduced susceptibility to Helicobacter pylori infection. H. pylori infects over half the world's population and causes diverse gastric lesions, from gastritis to gastric cancer. H. pylori adhesion constitutes a crucial step in the establishment of a successful infection. The BabA adhesin binds the Le(b) and H type 1 structures expressed on gastric mucins, while SabA binds to sialylated carbohydrates mediating the adherence to inflamed gastric mucosa. In this study, we have used an animal model of nonsecretors, Fut2-null mice, to characterize the glycosylation profile and evaluate the effect of the observed glycan expression modifications in the process of H. pylori adhesion. We have demonstrated expression of terminal difucosylated glycan structures in C57Bl/6 mice gastric mucosa and that Fut2-null mice showed marked alteration in gastric mucosa glycosylation, characterized by diminished expression of alpha(1,2)fucosylated structures as indicated by lectin and antibody staining and further confirmed by mass spectrometry analysis. This altered glycosylation profile was further confirmed by the absence of Fucalpha(1,2)-dependent binding of calicivirus virus-like particles. Finally, using a panel of H. pylori strains, with different adhesin expression profiles, we have demonstated an impairment of BabA-dependent adhesion of H. pylori to Fut2-null mice gastric mucosa, whereas SabA-mediated binding was not affected.

  • 8.
    Malm, Linus
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Hellman, Urban
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Medicin.
    Larsson, Göran
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Size determination of hyaluronan using a gas-phase electrophoretic mobility molecular analysis2012Ingår i: Glycobiology, ISSN 0959-6658, E-ISSN 1460-2423, Vol. 22, nr 1, s. 7-11Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hyaluronan (HA) is a linear non-sulfated polysaccharide mainly found in the extracellular matrix. The size of HA can vary from a fewq saccharides up to at least 25,000 units, reaching molecular weights of 10x103 kDa. HA has mainly biological functions, and both its size and tissue concentration play an important role in many physiological and phatological processes. It is relatively easy ti determine the HA concentration using enzyme-linked binding protein assays, but the molecular weight of HA has so far been shown to be a more challenging task to measure. Here, we present a method for size determination of HA using gas-phase electrophoretic mobility molecular analysis (GEMMA), which utilizes the electrophoretic mobility of molecules in air to estimate the molecular weight of the analyte. We show that this method gives reliable molecular weight estimations of HA in the range 30-2400 kDa, which covers almost its whole biological range. The average measuring time for one GEMMA spectrum is between 5 and 10 min using only 6 pg of HA. In addition the peak area in a GEMMA spectrum can be used to estimate the HA concentration in the sample. The high sensitivity and small sample volumes make GEMMA an excellent tool for both size determination and estimation of concentration of samples with low HA concentration, as is the case for HA extracted from small tissue samples.

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