ADAMTS13 phenotype in plasma from normal individuals and patients with thrombotic thrombocytopenic purpura

作者：Manea Minola; Kristoffersson AnnCharlotte; Tsai Han Mou; Zhou Wenhua; Winqvist Ingemar; Oldaeus Goran; Billstrom Rolf; Bjork Peter; Holmberg Lars; Karpman Diana^*

来源：European Journal of Pediatrics, 2007, 166(3): 249-257.

DOI：10.1007/s00431-006-0354-2

• ADAMTS13
• von Willebrand factor
• thrombotic thrombocytopenic purpura
• immunoblotting
• plasma
• von Willebrand factor cleaving protease

The activity of ADAMTS 13, the von Willebrand factor cleaving protease, is deficient in patients with thrombotic thrombocytopenic purpura (TTP). In the present study, the phenotype of ADAMTS13 in TTP and in normal plasma was demonstrated by immunoblotting. Normal plasma (n=20) revealed a single band at 190 kD under reducing conditions using a polyclonal antibody, and a single band at 150 kD under non-reducing conditions using a monoclonal antibody. ADAMTS 13 was not detected in the plasma from patients with congenital TTP (n=5) by either antibody, whereas patients with acquired TTP (n=2) presented the normal phenotype. Following immunoadsorption of immunoglobulins, the ADAMTS 13 band was removed from the plasma of the patients with acquired TTP, but not from that of normal individuals. This indicates that ADAMTS13 is complexed with immunoglobulin in these patients. The lack of ADAMTS13 expression in the plasma from patients with hereditary TTP may indicate defective synthesis, impaired cellular secretion, or enhanced degradation in the circulation. This study differentiated between normal and TTP plasma, as well as between congenital and acquired TTP. This method may, therefore, be used as a complement in the diagnosis of TTP.

• 出版日期2007-3