Development of a humanized anti-CD47 antibody for treatment of tissue ischemia.

描述（由申请人提供）：一氧化氮（NO）是心血管生理学的关键调节剂，协调内皮、血管壁和循环细胞的活动，以优化血液和氧气向组织的流动。增加NO的生物利用度应在治疗归因于NO生物利用度不足的许多疾病中提供治疗益处。所有目前的方法都受到Vasculox创始人发现的迄今未知的调节系统的限制，该系统限制了所有血管细胞中NO信号传导的作用。血小板反应蛋白-1（TSP 1）及其受体CD 47存在于所有血管组织中，并限制NO信号传导，从而恶化组织缺血，促进血栓形成和炎症，并加剧衰老对心血管系统的影响。阻断TSP-1和CD 47与单克隆抗体（mAb）的相互作用，防止在小鼠和猪模型的伤口愈合和组织缺血NO信号的这些限制作用。Vasculox的成立旨在将这些发现带入医疗保健市场。鉴于NO在心血管调节中的许多作用，我们预期阻断性抗CD 47 mAb将在许多疾病中具有治疗应用，例如外周动脉疾病（PAD）、缺血再灌注损伤、镰状细胞病、心肌梗死、中风、血栓形成等。在这里，我们计划开发商业化的抗CD 47单克隆抗体。这项STTR提案将为华盛顿大学医学院的Frazier博士实验室转移到Vasculox公司提供一种机制。选择mAb与CD 47用于随后的测试和开发作为治疗剂。最有希望用于未来开发的是在CD 47缺失小鼠中产生的针对人CD 47的一组mAb。这些mAb与人和小鼠CD 47均反应，将极大地促进用于临床试验的人源化抗CD 47功能阻断mAb的开发。在第一阶段的提案中，我们计划确定最有前途的候选mAb以供进一步开发。在随后的提案中，我们将在人类心血管疾病模型中测试这些候选人。第一阶段的具体目标是：1.测定表位特异性、种属反应性和对mAb配体结合的影响。2.鉴定那些在体外增强小鼠和人平滑肌细胞中NO信号传导的mAb。3.在组织缺血的MacFarlane皮瓣小鼠模型中测试活性候选物，并确定mAb施用的有效剂量、药代动力学参数和副作用。公共卫生相关性：Vasculox公司的创始人发现了一种调节受体CD 47，它控制着身体所有组织的血流，血压，血栓形成和其他心血管功能。阻断这种受体可以改善伤口愈合，血液流向垂死组织和其他血管参数。Vasculox的成立是为了将这一新发现应用于临床实践，通过识别抗体与CD 47，将其应用于临床开发，用于治疗外周血管疾病和其他心血管疾病，如中风和心脏病发作。

DESCRIPTION (provided by applicant): Nitric oxide (NO) is a critical regulator of cardiovascular physiology, coordinating the activities of the endothelium, the vessel wall and circulating cells to optimize the flow of blood and oxygen to tissues. Increasing the bioavailability of NO should provide therapeutic benefit in the treatment of many diseases ascribed to insufficient NO bioavailability. All current approaches are limited by a heretofore unknown regulatory system, discovered by the founders of Vasculox, that limits the effects of NO signaling in all vascular cells. Thrombospondin-1 (TSP1) and its receptor, CD47, are present in all vascular tissues and limit NO signaling, thus worsening tissue ischemia, promoting thrombosis and inflammation and exacerbating the effects of aging on the cardiovascular system. Blocking the interaction of TSP-1 and CD47 with a monoclonal antibody (mAb) prevents these limiting effects on NO signaling in both mouse and porcine models of wound healing and tissue ischemia. Vasculox was founded to bring these discoveries to the healthcare market. Given the many roles of NO in cardiovascular regulation, we anticipate that a blocking anti-CD47 mAb will have therapeutic applications in many diseases such as peripheral artery disease (PAD), ischemia-reperfusion injury, sickle cell disease, myocardial infarction, stroke, thrombosis and others. Here we plan to develop for commercialization an anti-CD47 monoclonal antibody. This STTR proposal will provide a mechanism for Dr. Frazier's lab at Washington University School of Medicine to transfer to Vasculox, Inc. selected mAbs vs CD47 for subsequent testing and development as therapeutics. Most promising for future development is a panel of mAbs raised in the CD47-null mice to human CD47. These mAbs react with both human and mouse CD47 and will greatly facilitate development of a humanized anti-CD47 function-blocking mAb for use in clinical trials. In this phase I proposal, we plan to identify the most promising candidate mAbs for further development. In subsequent proposals, we will test these candidates in models of human cardiovascular diseases. The phase I specific aims are: 1. Determine the epitope specificity, species reactivity and effect on ligand binding of mAbs. 2. Identify those mAbs with efficacy in augmenting NO signaling in mouse and human smooth muscle cells in vitro. 3. Test active candidates in the MacFarlane skin flap mouse model of tissue ischemia, and determine effective dose, pharmacokinetic parameters and side effects of mAb administration. PUBLIC HEALTH RELEVANCE: The founder of Vasculox Inc, has discovered a regulatory receptor, CD47, that governs blood flow to all tissues of the body, blood pressure, thrombosis and other cardiovascular functions. Blocking this receptor improves wound healing, blood flow to dying tissues and other vascular parameters. Vasculox was founded to bring this new discovery to clinical practice by identifying antibodies vs CD47 to take forward into clinical development for treatment of peripheral vascular disease and other cardiovascular diseases in the future such as stroke and heart attack.