Eliminating Mediators of Toxicity from Stored Blood

描述(申请人提供)：在美国，每年有近1500万单位的红细胞(RBC)被输注给大约500万名患者，RBC输注是住院患者最常用的处方疗法之一。近年来，大量的临床证据表明，在危重病患者中，有相当大比例的发病率和死亡率是由于输注红细胞的毒性作用造成的。大多数输血涉及在1-6摄氏度的抗凝剂-防腐剂溶液中储存长达6周的红细胞。红细胞的生化、机械和功能特性逐渐恶化--在允许储存结束时，高达1%的储存红细胞发生裂解，多达25%的剩余红细胞是无法修复的受损、不能存活的细胞。此外，RBC存储介质积累已知的毒性介质，作为RBC新陈代谢和降解的副产品。在输血过程中将这些有毒介质和不可修复的受损细胞注入受者体内会降低输血的治疗效果，并导致1%-2%的美国公民出现多种不良后果。该项目的目标是设计一种高通量技术，用于在输血过程中实时从存储的红细胞单元中在线移除存储介质中无法修复的受损细胞和有毒介体。该项目首先将重点放在拟议的毫升储存红细胞样本技术的设计和性能优化上。为了支持设计迭代，我们将开发一种芯片上辅助血液学设备，用于高通量测量数千个单个红细胞的所有相关几何、机械和生化特性。在项目的第二阶段，我们将扩大处理临床大小的红细胞单位的优化设计。我们将进行广泛的体外测试，以确定加工后的红细胞的质量。为了进行主要红细胞功能的综合测试，我们将开发另一种辅助设备，用于直接测量人工毛细血管网络中储存的红细胞加载/卸载氧的能力。该项目的预期结果是该设备的全尺寸原型，可用于进一步测试处理后保存完好的红细胞在体内的促炎和促血栓活性，以及输血后的生存能力和血管内存活率。传统的范式假定，就储存引起的性能劣化而言，袋子中所有储存的红细胞都是同质的，因此试图通过操纵总体储存条件和重新配制添加剂溶液来使储存的红细胞恢复活力。我们的方法通过利用储存的红细胞的异质性来挑战这一传统范式，使仅能够输注保存良好的细胞，而不是存储介质中的不可修复的受损细胞和毒素。这是一种全新的方法，对整个医学实践中输血的安全性和有效性具有潜在的改变游戏规则的、变革性的影响。

DESCRIPTION (provided by applicant): With nearly 15 million units of red blood cells (RBCs) transfused to about 5 million patients in the U.S. every year, RBC transfusion is one of the most commonly prescribed therapies for hospital inpatients. In recent years, ample clinical evidence has accumulated that a significant proportion of morbidity and mortality in critically ill patientsis due to the toxic effects of RBC transfusions. Most transfusions involve RBCs that had been stored in an anticoagulant-preservative solution at 1-6 C for up to 6 weeks. The biochemical, mechanical and functional properties of RBCs deteriorate progressively - by the end of allowable storage up to 1% of stored RBCs undergo lysis, and as many as 25% of the remaining RBCs are irreparably damaged, non-viable cells. Moreover, the RBC storage medium accumulates known mediators of toxicity as byproducts of RBC metabolism and degradation. Infusion of these toxic mediators and the irreparably damaged cells into the recipient during transfusion reduces the therapeutic efficacy of transfusion and contributes to multiple adverse outcomes in 1-2% of U.S. citizens. The goal of this project is to devise a high-throughput technology for in-line removal of irreparably damaged cells and toxic mediators in the storage medium from units of stored RBCs in real-time, during the transfusion process. This project will initially focus on the design and performance optimization of the proposed technology on milliliter-size samples of stored RBCs. To support the design iterations, we will develop an auxiliary hematology-on-a-chip device for measuring all relevant geometric, mechanical and biochemical properties for thousands of individual RBCs at high throughput. At the second stage of the project, we will scale up the optimized design for processing clinical-size RBC units. We will perform a broad panel of in vitro tests to characterize the quality of processed RBCs. To perform an integrative test of the primary RBC function, we will develop another auxiliary device for measuring the ability of stored RBCs to load / offload oxygen in artificial capillary networks directly. The anticipated outcome of this project is a full-scale prototype of the proposed device that can be used to further test the processed well- preserved stored RBCs for pro-inflammatory and pro-thrombotic activity, and post-transfusion viability and intravascular survival in human subjects in vivo. Conventional paradigm postulates that all stored RBCs in a bag are homogeneous with respect to the storage-induced deterioration of their properties, and consequently attempts to 'rejuvenate' stored RBCs through manipulation of the overall storage conditions and re-formulation of additive solutions. Our approach challenges this conventional paradigm by leveraging the heterogeneity of stored RBCs to enable transfusion of only well-preserved cells, free from irreparably damaged cells and toxins in the storage medium. This is an entirely novel approach with a potentially game-changing, transformative impact on the safety and efficacy of transfusions administered throughout the practice of medicine.