title: Identification of binding sites for anti-aquaporin 4 antibodies in patients with neuromyelitis optica.
abstract: OBJECTIVE
  Anti-aquaporin 4 antibodies (AQP4-Ab) are specifically detected in patients with neuromyelitis optica. To investigate the role of AQP4-Ab, we examined the antibody binding epitope using human and mouse mutant AQP4.
  
  
  METHODS
  We constructed human and mouse amino acid substitution AQP4 mutants and compared the reactivity with wild-form of human, mouse and rat AQP4.
  
  
  RESULTS
  The decreased intensity of AQP4-Ab staining with mouse AQP4 was recovered to that of human AQP4 with the mouse mutant A228E for 9 of the 10 sera.
  
  
  CONCLUSIONS
  The third extracellular loop of AQP4 is considered to be the major epitope for AQP4-Ab in NMO.
authors.affiliation: Department of Neurology, Brain Research Institute, Niigata University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Tani
authors.forename: K
authors.initials: K
authors.lastname: Sakimura
authors.forename: M
authors.initials: M
authors.lastname: Tsujita
authors.forename: T
authors.initials: T
authors.lastname: Nakada
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: M
authors.initials: M
authors.lastname: Nishizawa
authors.forename: K
authors.initials: K
authors.lastname: Tanaka
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D051401:Aquaporin 4 / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D001323:Autoantibodies / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D001666:Binding Sites, Antibody / Q000235:genetics / Q000276:immunology*; D000939:Epitopes / Q000276:immunology; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D008969:Molecular Sequence Data; D009471:Neuromyelitis Optica / Q000276:immunology*; D051381:Rats; D014162:Transfection
chemical_list: D051401:Aquaporin 4; D001323:Autoantibodies; D000939:Epitopes