@article{X. Long Zheng_Haifeng M. Wu_Dezhi Shang_Erica Falls_Christopher G. Skipwith_Spero R. Cataland_Charles L. Bennett_Hau C. Kwaan_2010, place={Pavia, Italy}, title={Multiple domains of ADAMTS13 are targeted by autoantibodies against ADAMTS13 in patients with acquired idiopathic thrombotic thrombocytopenic purpura}, volume={95}, url={https://haematologica.org/article/view/5721}, DOI={10.3324/haematol.2009.019299}, abstractNote={<strong>Background</strong> Type G immunoglobulins against ADAMTS13 are the primary cause of acquired (idiopathic) thrombotic thrombocytopenic purpura. However, the domains of ADAMTS13 which the type G anti-ADAMT13 immunoglobulins target have not been investigated in a large cohort of patients with thrombotic thrombocytopenic purpura.<strong>Design and Methods</strong> Sixty-seven patients with acquired idiopathic thrombotic thrombocytopenic purpura were prospectively collected from three major U.S. centers. An enzyme-linked immunosorbent assay determined plasma concentrations of anti-ADAMTS13 type G immunoglobulins, whereas immunoprecipitation plus western blotting determined the binding domains of these type G immunoglobulins.<strong>Results</strong> Plasma anti-ADAMTS13 type G immunoglobulins from 67 patients all bound full-length ADAMTS13 and a variant truncated after the eighth TSP1 repeat (delCUB). Approximately 97% (65/67) of patients harbored type G immunoglobulins targeted against a variant truncated after the spacer domain (MDTCS). However, only 12% of patients’ samples reacted with a variant lacking the Cys-rich and spacer domains (MDT). In addition, approximately 37%, 31%, and 46% of patients’ type G immunoglobulins interacted with the ADAMTS13 fragment containing TSP1 2-8 repeats (T2-8), CUB domains, and TSP1 5-8 repeats plus CUB domains (T5-8CUB), respectively. The presence of type G immunoglobulins targeted against the T2-8 and/or CUB domains was inversely correlated with the patients’ platelet counts on admission.<strong>Conclusions</strong&gt; This multicenter study further demonstrated that the multiple domains of ADAMTS13, particularly the Cys-rich and spacer domains, are frequently targeted by anti-ADAMTS13 type G immunoglobulins in patients with acquired (idiopathic) thrombotic thrombocytopenic purpura. Our data shed more light on the pathogenesis of acquired thrombotic thrombocytopenic purpura and provide further rationales for adjunctive immunotherapy.}, number={9}, journal={Haematologica}, author={X. Long Zheng and Haifeng M. Wu and Dezhi Shang and Erica Falls and Christopher G. Skipwith and Spero R. Cataland and Charles L. Bennett and Hau C. Kwaan}, year={2010}, month={Aug.}, pages={1555-1562} }