标题：ADAMTS-13 regulates platelet adhesion under flow. A new method for differentiation between inherited and acquired thrombotic thrombocytopenic purpura

作者：Shenkman B1, Budde U, Angerhaus D, Lubetsky A, Savion N, Seligsohn U, Varon D.

网址:PMID: 16894459

求助者：sk06c

• 求助时间：2015/6/27 15:27:23
• 求助状态：AB图书馆客服已找到全文，详情咨询在线客服qq 1257749646
• 文献摘要：

ADAMTS-13 cleaves large and ultra-large von Willebrand factor multimers normally secreted by endothelial cells. Severe deficiency of this enzyme leads to thrombotic thrombocytopenic purpura (TTP). We applied the Impact-R system [Cone and plate(let) Analyzer, CPA] to determine optimal conditions for ADAMTS-13 function, to assess it´s activity in TTP patients and to distinguish inherited TTP (inTTP) from acquired TTP (acTTP). The role of ADAMTS-13 in platelet adhesion under different conditions was investigated applying recombinant forms of VWF and ADAMTS-13. rVWF was first treated by rADAMTS-13 either in solution or when immobilized on the surface of the well, under static or flow conditions, in the presence or absence of BaCl2. The resulting cleaved VWF fragments were then immobilized and served to assess type 3 von Willebrand disease whole blood platelet adhesion under flow. Maximal effect of the rADAMTS-13 (decrease of platelet adhesion in the absence compared to the presence of BaCl2), was observed when the rVWF was pre-immobilized and the cleavage step took place under flow (85%). Mixing plasma ofTTP patients with normal blood (1:3) yielded a 1.6- to 2-fold increase of platelet adhesion under flow compared to mixing normal plasma with normal blood, at shear rate range of 1,800 - 2,500 s(-1) . Maximal increase of platelet adhesion was observed under 2,050 s(-1) . Under these conditions, the extent of adhesion was similarly higher in patients with inTTP and acTTP versus control [surface coverage (SC) 14.5 +/- 2.8% and 14.6 +/- 2.5% vs.7.4 +/- 1.7%, respectively]. ADAMTS-13 activity measured by collagen-binding test was similarly low (4.2 +/- 3.8% and 3.5 +/- 2.4% vs. 72.2 +/- 8.0%, respectively). An inverse correlation between SC and ADAMTS-13 activity was observed in a patient with inTTP assayed eight times during plasma infusion treatment. Addition of BaCl2 to the mixture of TTP plasma and normal whole blood yielded a decrease in platelet adhesion in inTTP (by 51%) but not in acTTP. The lack of reduction of platelet adhesion in acTTP could presumably be due to the presence of ADAMTS-13 inhibitor in these patients. These results suggest that VWF immobilization and high shear flow yielded optimal conditions for ADAMTS-13 activity, and that introduction of BaCl2 in the Impact-R (CPA) test may be useful for differentiation between inherited and acquired TTP.

文献《ADAMTS-13 regulates platelet adhesion under flow. A new method for differentiation between inherited and acquired thrombotic thrombocytopenic purpura》已经找到全文，详情请咨询在线客服 qq 1257749646。
如果您还有其他需要寻找全文的文献，请点击文献求助提交

说明：文献求助是指AB图书馆根据读者的需求，为读者查找论文资料的服务。如果您搜索到相关资料，但不能获取全文，此时便可将有关信息提交求助，由值班客服为您寻找所需文献的全文。提供的文献均来自网络共享资源，不涉及版权交易；如侵犯了您的权利，请告知在线客服，立马删除。文件格式以PDF格式为主。