title: Studies of Lewis antigens and H. pylori adhesion in CHO cell lines engineered to express Lewis b determinants.
abstract: 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.
authors.affiliation: Division of Clinical Immunology and Transfusion Medicine, Karolinska Institute, SE 14186 Stockholm, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Löfling
authors.forename: Mette
authors.initials: M
authors.lastname: Diswall
authors.forename: Sara
authors.initials: S
authors.lastname: Eriksson
authors.forename: Thomas
authors.initials: T
authors.lastname: Borén
authors.forename: Michael E
authors.initials: ME
authors.lastname: Breimer
authors.forename: Jan
authors.initials: J
authors.lastname: Holgersson
mesh_terms: D000818:Animals; D001422:Bacterial Adhesion; D016466:CHO Cells; D006224:Cricetinae; D003412:Cricetulus; D016695:Glycosyltransferases / Q000235:genetics / Q000378:metabolism; D016480:Helicobacter pylori / Q000502:physiology*; D007983:Lewis Blood Group Antigens / Q000096:biosynthesis* / Q000235:genetics; D009844:Oligosaccharides / Q000096:biosynthesis* / Q000235:genetics; D011499:Protein Processing, Post-Translational
chemical_list: D007983:Lewis Blood Group Antigens; C094162:Lewis Y antigen; C494219:Lewis a oligosaccharide; D009844:Oligosaccharides; C404741:galactopyranosyl-1-3-galactopyranosyl-1-3(4)-N-acetylglucosamine; D016695:Glycosyltransferases