Red blood cell ATP export and transfusion in sepsis

脓毒症中红细胞 ATP 输出和输血

• 批准号: 10584768
• 负责人: ALLAN DOCTOR
• 金额: $ 73.14万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-03-05 至 2026-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10584768
• 关键词: Acute Lung Injury; Acute Respiratory Distress Syndrome; Adenine; Adhesions; Adhesives; Adult; Anemia; Attenuated; Blood; Blood Transfusion; Blood Vessels; Blood flow; Blood specimen; Caliber; Cardiac Output; Cells; Child; Clinical; Consumption; Coupling; Critical Illness; Cryopreserved Cell; Depressed mood; Endothelial Cells; Endothelium; Ensure; Erythrocyte Transfusion; Erythrocytes; Exposure to; Functional disorder; Genetic; Hemoglobin; Homeostasis; Human; Hypoxemia; Hypoxia; Immune response; Impairment; In Vitro; Incubated; Infection; Inflammation; Influenza; Inosine; Intervention; Investigation; Leukocytes; Lung; Mediating; Mediator; Metabolic; Methods; Modeling; Morbidity - disease rate; Mus; Oral; Organ; Outcome; Oxygen; Patients; Peripheral; Persons; Phase; Phenotype; Pyruvate; Pyruvate Kinase; Respiration Disorders; Respiratory physiology; Risk; Risk Factors; Role; Sampling; Scheme; Sepsis; Signal Transduction; Site; Specimen; Testing; Therapeutic; Tissues; Transfusion; Translations; biobank; candidate identification; cecal ligation puncture; cell injury; cell type; clinical investigation; clinical translation; clinically relevant; design; empowerment; experimental study; genetic approach; improved; in vivo; inorganic phosphate; insight; lead candidate; mortality; mouse model; novel; pharmacologic; preservation; prospective; respiratory; response; septic; tissue oxygenation; uptake

ABSTRACT O2 uptake in the lung and O2 delivery peripherally depend on the efficient matching of blood flow to regional O2 availability in the lung and O2 consumption in tissues. To achieve this matching, red blood cell (RBC) hemoglobin allostery regulates not only trans-erythrocytic O2 flux but also RBC export of vasoactive mediators that respond to O2 demand. RBCs export vasoregulatory ATP basally and in response to O2 deficit. This RBC-based vascular control of the uptake and delivery of O2 may be disrupted by endogenous (e.g., in sepsis) and exogenous (via storage for transfusion) RBC injuries. Septic persons with moderate anemia are frequently transfused, but infrequently benefit. Yet conversely any anemia is a negative risk factor. Lung morbidity is frequent after RBC transfusion, possibly due to impaired RBC ability to export ATP, disrupting O2 uptake via pulmonary RBC- endothelial adhesion. We show in septic mice (cecal ligation/puncture, CLP) that the RBC’s ability to produce and export ATP is impaired. We will test the hypothesis that the O2-transport dysfunction in sepsis is mediated in part by impaired export by RBCs of vasoregulatory ATP, a dysfunction compounded by transfused RBCs, exacerbating acute lung injury (ALI) and hypoxemia, by achieving these Aims: Aim 1. Determine the role of RBC ATP export in mortality and ALI in a mouse model of sepsis and transfusion. Exchange transfusion of CLP RBCs into healthy mice exposed to hypoxia drives mortality. RBC ATP export takes place via pannexin 1 (Px1). We will determine the role and mechanism of depressed RBC ATP export via Px1 in the mortality, ALI, and O2 transport responses to sepsis (CLP or severe influenza) and transfusion in mice using genetic and pharmacological approaches. Aim 2. Determine the influence of augmenting transfusate RBC ATP content and/or export on organ function and O2 transport in septic mice. RBC ATP export can be augmented via clinically available approaches: hypoxic RBC storage; transfusate incubation with PIPA (phosphate, inosine, pyruvate, adenine) solution that preserves stored-RBC ATP and DPG; or using an activator of RBC pyruvate kinase (PKR), which augments RBC ATP with little effect on DPG or P50. We will test these approaches to augment or preserve RBC ATP content on ATP export in mice transfused during sepsis. Aim 3. Determine the influence of human sepsis on RBC vasoregulatory function ex vivo, and the functional influence of candidate modulators of ATP content and export in septic RBCs. We validated a novel RBC cryopreservation scheme with superior phenotype fidelity. We built a unique biobank of RBC specimens from septic children and adults. We prospectively sampled over 150 patients with severe sepsis; most subjects have ALI. We will determine the influence of translation-ready lead candidates identified in Aim 2 to augment RBC ATP export on key RBC respiratory functions: vasoactivity, anti-adhesivity, and O2 transport. We will model the effects of transfusate intervention in admixed septic and stored RBCs. Our novel focus on disrupted signaling by RBCs will produce novel, practical, and relevant insight into respiratory dysfunction in sepsis and transfusion.

抽象的 肺中的O2摄取几乎取决于血流与区域O2的有效匹配 组织中肺和O2消耗的可用性。为了达到这种匹配，红细胞（RBC）血红蛋白 变构不仅调节trans骨细胞O2通量，还可以调节反应响应的血管活性介质的RBC导出 满足O2的需求。 RBCS出口血管调节ATP基本和响应O2防御。基于加拿大皇家骑警的血管 O2的摄取和递送的控制可能会被内源性（例如，败血症）和外源性破坏（通过 输血的存储）RBC损伤。中度贫血的化粪池经常被输血，但 很少受益。但是，相反，任何贫血都是负面的危险因素。 RBC之后的肺发病率经常 输血，由于RBC的出口能力受损而可能导致ATP的能力，从而破坏了O2通过肺RBC- 内皮粘附。我们在化脓性小鼠（Cecal结扎/穿刺，CLP）中表明，RBC的生产能力 出口ATP受损。我们将检验以下假设：败血症中的O2-Transport功能障碍 由RBC的血管调节ATP的RBC部分介导的，该功能障碍复杂 通过实现这些目的，输血的RBC，加剧急性肺损伤（ALI）和低氧血症：目标1。 确定RBC ATP输出在死亡率和ALI中的作用，在败血症和输血的小鼠模型中。 将CLP RBC的输血交换为暴露于缺氧的健康小鼠会导致死亡率。 RBC ATP导出 通过Pannexin 1（PX1）进行。我们将通过 PX1在死亡率，ALI和O2对败血症（CLP或严重影响）的转运反应以及小鼠转移 使用遗传和药物方法。目标2。确定增强输血物的影响 RBC ATP含量和/或化粪池中器官功能和O2转运的导出。 RBC ATP导出可以 通过临床上可用的方法进行增强：低氧RBC存储；与PIPA孵育 （磷酸盐，肌苷，丙酮酸，腺嘌呤）溶液可保留储存的RBC ATP和DPG；或使用激活器 RBC丙酮酸激酶（PKR）的摄入，它增加了RBC ATP，对DPG或P50影响很小。我们将测试这些 在败血症期间输出的小鼠中ATP出口的增加或保留RBC ATP含量的方法。目标3。 确定人类败血症对RBC血管调节功能的影响，并具有功能 ATP含量和输出式RBC中的候选调节剂的影响。我们验证了一个新颖的RBC 冷冻保存方案具有优越的表型保真度。我们从 化粪池和成人。我们前瞻性地采样了150多名严重败血症患者。大多数受试者都有 阿里。我们将确定在AIM 2中确定的可改用翻译的主要候选者的影响以增强RBC 关键RBC呼吸功能的ATP导出：血管活性，抗粘附性和O2转运。我们将建模 在混合性粘液和储存的RBC中，输血液干预的影响。我们的小说专注于被破坏的信号传导 RBC将对败血症和输血中的呼吸障碍产生新颖，实用和相关的见解。