title: ADAMTS13 assays and ADAMTS13-deficient mice.
abstract: OBJECTIVE
  Thrombotic thrombocytopenic purpura can be induced by acquired or congenital deficiency of the plasma von Willebrand factor-cleaving protease, ADAMTS13. Measurement of ADAMTS13 activity is important for the diagnosis and treatment of microangiopathies including thrombotic thrombocytopenic purpura. Phenotypic analysis of mice lacking the Adamts13 gene is valuable for understanding the pathogenesis of microangiopathies.
  
  
  RESULTS
  The minimum substrate for ADAMTS13 activity was identified as 73 amino acid residues in the A2 domain of von Willebrand factor, called VWF73. Several new assays have been developed using this sequence. The VWF73-based assays are rapid, quantitative, and easy to handle, and are well correlated with the measures from previous assays. Mice lacking the Adamts13 gene were produced. The mice were viable and fertile. They showed a prothrombotic state but no symptoms of spontaneous thrombocytopenia, hemolytic anemia, or microvascular thrombosis were observed.
  
  
  CONCLUSIONS
  VWF73-based ADAMTS13 assays will significantly facilitate the accurate diagnosis of microangiopathies and contribute to the improved clinical treatment of these diseases. Accumulated clinical information on patients with ADAMTS13 deficiency and mice lacking the Adamts13 gene indicates that additional environmental or genetic susceptibility factors are required to trigger thrombotic thrombocytopenic purpura.
authors.affiliation: National Cardiovascular Center Research Institute, Fujishirodai, Suita, Osaka, Japan. miyata@ri.ncvc.go.jp
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Miyata
authors.forename: Koichi
authors.initials: K
authors.lastname: Kokame
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Banno
authors.forename: Yongchol
authors.initials: Y
authors.lastname: Shin
authors.forename: Masashi
authors.initials: M
authors.lastname: Akiyama
mesh_terms: D000071120:ADAMTS13 Protein; D000818:Animals; D020022:Genetic Predisposition to Disease; D008666:Metalloendopeptidases / Q000032:analysis* / Q000172:deficiency / Q000235:genetics; D051379:Mice; D010641:Phenotype; D011697:Purpura, Thrombotic Thrombocytopenic / Q000175:diagnosis
chemical_list: C502939:ADAMTS13 protein, mouse; D008666:Metalloendopeptidases; D000071120:ADAMTS13 Protein