Properties of stored RBCs: minimization of immune and vascular reactivity

项目摘要 输血是急性失血或血液学紊乱受试者的救命干预措施， 在美国，每年大约有500万人接受红细胞输注。而 输血显然可以帮助那些有需要的人，输血的免疫和炎症副作用可能 对输血接受者有不利影响。最近的临床研究表明， 可能与某些患者人群的结局恶化相关。本研究的目的 建议是发现储存的RBC单位中发生的变化，并测试逆转或防止 这些变化。这项研究的重点将是确定红细胞单位如何影响先天性和适应性免疫 以及红细胞单位的储存如何改变这些反应和血管反应性 输血效应除了详细的体外研究外，该提案还将探索这些相同的参数， 临床试验的参与者将血液年龄与危重输血受者的临床结果相关联。 这一提议背后的广泛假设是，红细胞的储存增加了它们调节免疫的能力， 反应和激活输血受体的血管内皮细胞。白细胞减少的红细胞单位将 在整个储存过程中表征为调节先天性和适应性免疫应答的能力。红细胞- 内皮细胞相互作用将使用尖端的流动池技术来测量， 和RBC与内皮细胞粘附的强度，并测量暴露于 新鲜和储存的RBC单位。在定义了免疫调节和血管激活的变化后， 储存的红细胞的性质，防止这些变化的方法将被探索。复杂的免疫学 在RBC暴露后进行测量，包括细胞因子/趋化因子的多重测量 T细胞和中性粒细胞中的诱导、增殖反应的诱导以及调节和IL-17的偏斜 分泌T细胞亚群为了测试研究结果的体内相关性，测量的免疫参数 将扩展至随机临床试验中接受短期与长期储存RBC单位的受试者， 并且相关的免疫参数将与疾病结果相关（例如，免疫抑制是否与 感染并发症？）。 这项研究提案加入了一个具有互补专业知识的研究团队，以显着推进我们的研究。 了解输血的潜在有害免疫调节和血管激活作用及其 依赖于RBC的储存。重要的是，该提案将验证所获得的知识和系统 在人体临床试验中开发，并将评估预防红细胞储存有害影响的方法 使用体外系统。

Project Summary Blood transfusion is a life-saving intervention for subjects with acute blood loss or hematological disturbance, and approximately 5 million people per year receive red blood cell transfusions annually in the US. While blood transfusions clearly help those in need, the immune and inflammatory side-effects of transfusions may have detrimental consequences in transfusion recipients. Recent clinical studies suggest that older RBC units may be associated with worsened outcome in some patient populations. The purpose of this research proposal is to discover changes that occur in stored RBC units and test methods of reversing or preventing these changes. The thrust of the research will be to define how RBC units affect innate and adaptive immune responses and vascular reactivity in transfusion recipients and how storage of RBC units can alter these transfusion effects. In addition to detailed in vitro studies, the proposal will explore these same parameters in participants of a clinical trial correlating age of blood with clinical outcome in critically ill transfusion recipients. The broad hypothesis behind this proposal is that storage of RBCs increases their ability to modulate immune responses and to activate vascular endothelial cells in transfusion recipients. Leukoreduced RBC units will be characterized throughout storage for the ability to modulate innate and adaptive immune responses. RBC- endothelial cell interaction will be measured using cutting-edge flow cell technology to measure the frequency and strength of RBC adhesion to endothelial cells and to measure the activation of endothelial cells exposed to fresh and stored RBC units. After defining the changes in the immunomodulatory and vasoactivating properties of stored RBCs, methods of preventing these changes will be explored. Sophisticated immunology measurements will be made after RBC exposure, including multiplex measurement of cytokine/chemokine induction in T cells and neutrophils, induction of proliferative responses, and skewing of regulatory and IL-17 secreting T cell subsets. To test the in vivo relevance of the study findings, the immune parameters measured will be extended to subjects receiving RBC units stored for short vs. long periods in a randomized clinical trial, and relevant immune parameters will be correlated with disease outcome (e.g. is immune suppression linked with infectious complications?). This research proposal joins a team of investigators with complementary expertise to significantly advance our knowledge of potentially harmful immunomodulatory and vasoactivating effects of transfusion and their dependence on storage of RBCs. Importantly, the proposal will validate the knowledge gained and systems developed in a human clinical trial and will evaluate methods of preventing harmful effects of RBC storage using in vitro systems.