Cell-Cell Interactions in Thrombosis -Request for Extension of Merit Award

冠状动脉、脑动脉和外周动脉损伤可引起局部血小板活化、聚集和血栓形成 闭塞预防和治疗血小板驱动的血栓形成是一项治疗挑战， 公共卫生影响。在存在内皮细胞的情况下，血小板对激动剂无反应。你的无礼- 由于内皮细胞NTPDasel/CD 39/外膜-ADP酶，其快速代谢ATP和ADP释放 激活的血小板。这就取消了聚集和招募。重组可溶性人CD 39（solCD 39） 在体外阻断人血小板聚集，并在体外抑制猪和常规血小板聚集。CD 39无效 小鼠表现出潜在的血栓形成前表型，对中风和心肺疾病的易感性增加， 血栓形成这在野生型和CD 39缺失小鼠中通过输注solCD 39而减轻，证明了其关键作用。 血栓调节作用。广泛的长期目标和具体目标包括： 人sol ⑶ 39的功能研究：测定所选突变体的抗血栓形成功效， ADP特异性/活性，以及评估二硫键对CD 39活性的贡献。11影响研究 缺血时NTPDases对细胞间信号传导的影响：心肌NTPDases对去甲肾上腺素释放的调节 交感神经末梢（cSNE）和来自豚鼠、野生型和CD 39缺失小鼠的分离的心脏。识别 来自小鼠和人心脏的cSNE中的外核苷酸酶补体，以及肺保护的评估 内源性和外源性CD 39在第二器官灌注损伤中的作用，在野生型和CD 39敲除小鼠中。I]1 冠状动脉造影患者淋巴细胞NTPD酶活性的研究 疾病（CAD），以确定是否有改变，血栓前核苷酸酶谱表达相比， 来自健康捐赠者的淋巴细胞。E来源于AMP的腺苷的代谢，如由来自 ATP和ADP：PRP能否代谢AMP并通过腺苷的产生抑制血小板反应性？ 5 '-核苷酸酶？如果是真的，这是否依赖于特定的血小板激动剂，或其他血液或内皮细胞？二恶英 毒性可能涉及通过腺苷脱氨酶的上调而增加腺苷的催化活性，从而降低 腺苷是一种有效的血小板抑制剂。这项研究代表了一种多学科的方法， 了解CD 39作为血小板介导的闭塞性血栓形成的主要调节因子的关键作用。它是基于 基于令人信服的可行性数据和历史合作成功，并将促进对NTPDase的理解 生物学和血栓调节，最终成为一种独特的新型血栓素质治疗剂。

Injury to coronary, cerebral, and peripheral arteries evokes local platelet activation, recruitment, and thrombotic occlusion. Prevention and treatment of platelet-driven thrombus formation is a therapeutic challenge, with critical public health implications. In the presence of endothelial cells, platelets are unresponsive to agonists. This unrespon- siveness is due to endothelial NTPDasel/CD39/ecto-ADPase, which rapidly metabolizes ATP and ADP released from activated platelets. This abolishes aggregation and recruitment. Recombinant, soluble human CD39 (solCD39) blocks human platelet aggregation in v#ro, and inhibits porcine and routine platelet aggregation ex vivo. CD39 null mice exhibit a latent prothrombotic phenotype with increased susceptibility to stroke and cardiac and pulmonary thrombosis. This is alleviated in both wild-type and CD39 null mice by infusion of solCD39, demonstrating its critical role in thromboregulation. Broad, long-term objectives and specific aims include: I Molecular, biochemical and functional studies of human solCD39: Determination of the antithrombotic efficacy of selected mutants with increased ADP specificity/activity, and evaluation of the contribution of disulfide bridges to CD39 activity. 11Studies of the effects of NTPDases on cell-cell signaling during ischemia: Modulation of norepinephrine release by NTPDases from cardiac sympathetic nerve endings (cSNE) and isolated hearts from guinea pigs, wild type and CD39 null mice. Identification of the ecto-nucleotidase complement in cSNE from mouse and human heart, and assessment of pneumoprotection by endogenous and exogenous CD39 during second organ perfusion injury, inwild-type and CD39 null mice. I]1 Studies of NTPDase activities in lymphocytes from patients with angiographically documented coronary artery disease (CAD) to determine whether an altered, prothrombotic nucleotidase profile is expressed in comparison to that of lymphocytes from healthy donors. E Metabolism of adenosine derived from AMP as generated by CD39 from ATP and ADP: Can PRP metabolize AMP and generate inhibition of platelet reactivity by production of adenosine via 5'-nucleotidase? If true, is this dependent on specific platelet agonists, or on other blood or endothelial cells? Dioxin toxicity may involve increased catabolism of adenosine via upregulation of adenosine deaminase, thus reducing availability of adenosine, a potent platelet inhibitor. The research represents a multidisciplinary approach to understanding the critical role of CD39 as the prime regulator of platelet-mediated occlusive thrombosis. It is based on compelling feasibility data and historical collaborative success, and will advance the understanding of NTPDase biology and thromboregulation, culminating in a unique and novel therapeutic agent for thrombotic diatheses.