title: Anti-laminin gamma-1 pemphigoid.
abstract: Anti-p200 pemphigoid has been characterized by autoantibodies to an unidentified 200-kDa protein (p200) of the dermal-epidermal junction. The objective of this study was to identify p200. We performed 2D gel electrophoresis of dermal extracts and immunoblotting with patients' sera, followed by MS analysis of a unique protein band. The protein band corresponded to laminin gamma1. Anti-laminin gamma1 mAb reacted with the anti-p200 immunoprecipitates by immunoblotting. Sera from 32 patients with anti-p200 pemphigoid showed 90% reactivity to the recombinant products of laminin gamma1. None of the healthy control sera reacted with laminin gamma1. By immunoblotting, reactivity of a patient's serum with p200 was competitively inhibited by adding anti-laminin gamma1 C-terminus mAb. Purified anti-p200 IgG also inhibited the reactivity of this mAb to dermal laminin gamma1. Most laminin gamma1-positive sera showed reactivity with recombinant laminin gamma1 C-terminal E8 fragment. Reactivity of patients' sera and purified IgG to dermal laminin gamma1 was higher than reactivity to blood vessel laminin gamma1 under reducing conditions. These results suggest that laminin gamma1 is the autoantigen for patients with anti-p200 pemphigoid. The autoantibodies may specifically recognize dermal laminin gamma1 with unique posttranslational modifications. The epitope is localized to the 246 C-terminal amino acids within the coiled-coil domain. The 9 C-terminal residues are known to be critically involved in laminin recognition by integrins.
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, Fukuoka 830-0011, Japan.
authors.forename: Teruki
authors.initials: T
authors.lastname: Dainichi
authors.forename: Sadamu
authors.initials: S
authors.lastname: Kurono
authors.forename: Bungo
authors.initials: B
authors.lastname: Ohyama
authors.forename: Norito
authors.initials: N
authors.lastname: Ishii
authors.forename: Noriko
authors.initials: N
authors.lastname: Sanzen
authors.forename: Maria
authors.initials: M
authors.lastname: Hayashi
authors.forename: Chisei
authors.initials: C
authors.lastname: Shimono
authors.forename: Yukimasa
authors.initials: Y
authors.lastname: Taniguchi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Koga
authors.forename: Tadashi
authors.initials: T
authors.lastname: Karashima
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Yasumoto
authors.forename: Detlef
authors.initials: D
authors.lastname: Zillikens
authors.forename: Kiyotoshi
authors.initials: K
authors.lastname: Sekiguchi
authors.forename: Takashi
authors.initials: T
authors.lastname: Hashimoto
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology*; D001323:Autoantibodies / Q000737:chemistry / Q000276:immunology*; D015153:Blotting, Western; D015180:Electrophoresis, Gel, Two-Dimensional; D000939:Epitopes / Q000737:chemistry; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D047468:Immunoprecipitation; D007797:Laminin / Q000276:immunology*; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010391:Pemphigoid, Bullous / Q000276:immunology*; D012867:Skin / Q000276:immunology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000911:Antibodies, Monoclonal; D001323:Autoantibodies; D000939:Epitopes; D007797:Laminin; C089141:laminin gamma 1