title: Restricted expression of shiga toxin binding sites on mucosal epithelium of mouse distal colon.
abstract: Shiga toxins (Stx) are some of the major virulence factors of enterohemorrhagic Escherichia coli strains such as serotype O157:H7. To explore how Stx might initially gain access to the bloodstream from sites of infection, frozen sections of mouse colon were immunohistochemically examined for binding sites for recombinant binding subunits (Stx1B). Binding sites were selectively expressed on the epithelium in the distal half of the mouse colon, whereas the proximal half did not exhibit any binding sites. In agreement with this observation, we also demonstrated the distal-part-restricted distribution of glycolipids that bind to Stx1B in the mouse colon. For comparison, the binding sites of several control lectins were also examined. Selective binding to the distal part of the colon was not seen with any other control lectins, including Griffonia simplicifolia lectin-I isolectin B4 (GS-I-B4), which shares alpha-galactose specificity with Stx1B. Partial overlapping of the specificities of Stx1B and GS-I-B4 was seen by assay with globotriose-conjugated multivalent ligands. The results indicate that Stx1B is stricter in the recognition of carbohydrate determinants than GS-I-B4 when examined with biological ligands.
authors.affiliation: Department of Microbiology, University of Shizuoka School of Pharmaceutical Sciences, Japan. imai@u-shizuoka-ken.ac.jp
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Imai
authors.forename: Takashi
authors.initials: T
authors.lastname: Fukui
authors.forename: Kohta
authors.initials: K
authors.lastname: Kurohane
authors.forename: Daisei
authors.initials: D
authors.lastname: Miyamoto
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Ishikawa
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Ono
authors.forename: Masaki
authors.initials: M
authors.lastname: Miyake
mesh_terms: D000818:Animals; D001665:Binding Sites; D003106:Colon / Q000166:cytology / Q000378:metabolism*; D004848:Epithelium / Q000378:metabolism*; D005260:Female; D006017:Glycolipids / Q000378:metabolism; D007150:Immunohistochemistry; D037102:Lectins / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D009092:Mucous Membrane / Q000166:cytology / Q000378:metabolism*; D022621:Shiga Toxin / Q000235:genetics / Q000378:metabolism*
chemical_list: D006017:Glycolipids; D037102:Lectins; D022621:Shiga Toxin