title: Anti-early endosome antigen 1 autoantibodies were detected in a pemphigus-like patient but not in the majority of pemphigus diseases.
abstract: Although the major autoantigens in classic pemphigus are desmogleins, sera from various types of pemphigus react with a number of other molecules, including desmocollins and plakin proteins. However, other novel pemphigus-related autoantigens remain to be identified. In this study, immunoblotting for serum from an atypical autoimmune bullous disease patient identified an unknown 175 kDa protein. Subsequent studies using two-dimensional gel electrophoresis, immunoblotting and mass-spectrometry identified the 175 kDa protein as early endosome antigen 1 (EEA1). This finding was confirmed by subsequent immunological studies, including indirect immunofluorescence of skin and cultured keratinocytes, two-dimensional gel electrophoresis and immunoblotting with anti-EEA1 polyclonal antibody, and preabsorption with EEA1 recombinant protein. Finally, we developed a novel BIOCHIP assay using full-length EEA1 recombinant protein to detect anti-EEA1 antibodies. However, none of 35 sera from various types of pemphigus showed anti-EEA1 antibodies in the BIOCHIP assay, with the exception of the serum from the index case. In addition, various findings in the index case did not suggest pathogenic role of anti-EEA1 autoantibodies. Therefore, although we successfully identified the 175 kDa protein reacted by a serum of an atypical pemphigus-like patient as EEA1, novel BIOCHIP study for other pemphigus sera indicated that EEA1 is not a common and pathogenic autoantigen in pemphigus.
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Ryuhei
authors.initials: R
authors.lastname: Nishikawa
authors.affiliation: Department of Dermatology, Shimane University Faculty of Medicine, Izumo, Shimane, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Matsuda
authors.affiliation: Department of Dermatology, Shimane University Faculty of Medicine, Izumo, Shimane, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Imaoka
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ogawa
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Kwesi
authors.initials: K
authors.lastname: Teye
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Atsunari
authors.initials: A
authors.lastname: Tsuchisaka
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Koga
authors.affiliation: Institute for Experimental Immunology, Affiliated to Euroimmun AG, Luebeck, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Komorowski
authors.affiliation: Institute for Experimental Immunology, Affiliated to Euroimmun AG, Luebeck, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Probst
authors.affiliation: Antibody Engineering Department/Manufacturing Division, Medical & Biological Laboratories Co., Ltd., Nagoya, Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Hachiya
authors.affiliation: Cumming School of Medicine, University of Calgary, Calgary, Canada.
authors.forename: Marvin J
authors.initials: MJ
authors.lastname: Fritzler
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Norito
authors.initials: N
authors.lastname: Ishii
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Chika
authors.initials: C
authors.lastname: Ohata
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Minao
authors.initials: M
authors.lastname: Furumura
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Rafal P
authors.initials: RP
authors.lastname: Krol
authors.affiliation: Division of Connective Tissue Disease and Autoimmunity, Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: Yoshinao
authors.initials: Y
authors.lastname: Muro
authors.affiliation: Department of Dermatology, Shimane University Faculty of Medicine, Izumo, Shimane, Japan.
authors.forename: Eishin
authors.initials: E
authors.lastname: Morita
authors.affiliation: Department of Dermatology, Kurume University School of Medicine, and Kurume University Institute of Cutaneous Cell Biology, Kurume, Fukuoka, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Hashimoto
mesh_terms: D000818:Animals; D001323:Autoantibodies / Q000276:immunology*; D019556:COS Cells; D002522:Chlorocebus aethiops; D006801:Humans; D008297:Male; D008875:Middle Aged; D010392:Pemphigus / Q000276:immunology*; D033921:Vesicular Transport Proteins / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D033921:Vesicular Transport Proteins; C093846:early endosome antigen 1
keywords: BIOCHIP; EEA1; autoantibodies; endocytosis; pemphigus