MICRODEVICES FOR MEASURING CPB SYSTEMIC INFLAMMATION

描述（由申请人提供）：几项研究表明，心脏手术会诱导全身炎症反应，特别是在使用心肺转流术（CPB）时。CPB诱导复杂的炎症反应，其特征在于补体、中性粒细胞和血小板活化，以及促炎细胞因子的释放。大量证据表明，全身性炎症导致许多术后并发症，包括可导致多器官衰竭甚至死亡的重要器官功能障碍。炎症反应的强度似乎与CPB相关发病率的严重程度直接相关。临床干预炎症或甚至研究对CPB的炎症反应的能力受到缺乏炎症反应（补体、中性粒细胞、单核细胞、血小板活化和促炎细胞因子释放）的及时测量的限制。预期使用如本文所述的装置实时测量细胞因子和补体浓度的产生将与通过常规ELISA技术获得的测量相关。更直接的测量将有助于理解细胞活化的机制，并修改手术和灌注方案，以尽量减少心肺转流术的不良影响。拟议的研究旨在开发一种新的方法来测量血浆细胞因子和补体浓度在一个连续的实时方式在一个微流控分析系统在线监测CPB过程中的炎症反应。微系统包括一个血浆自动分离装置和一个新的微量免疫测定连续测量。测量方法将使用微制造技术来创建血液携带流体回路，并将在使用供体人血的体外模拟心肺转流手术中进行评价。微量免疫测定基于控制免疫测定珠的移动，所述免疫测定珠将通过一系列流动流，所述流动流包括具有随时间变化的细胞因子和补体浓度的感兴趣的血浆样品、洗涤溶液、二抗溶液和检测区。将对两种设计进行评估。第一种设计使用磁珠，其运动由磁场控制以在流动流之间通过，而第二种设计使用特别设计的流动结构以允许珠在不同流动流之间通过而不混合或稀释。

DESCRIPTION (provided by applicant): Several studies have shown that cardiac surgery induces systemic inflammatory responses, particularly when cardiopulmonary bypass (CPB) is used. CPB induces complex inflammatory responses characterized by complement, neutrophil, and platelet activation, and the release of pro-inflammatory cytokines. Considerable evidence suggests that systemic inflammation causes many postoperative complications, including vital organ dysfunction that can lead to multi-organ failure and even death. The intensity of the inflammatory response appears to be directly correlated with the severity of CPB-related morbidity. The ability to clinically intervene in inflammation, or even study the inflammatory response to CPB, is limited by the lack of timely measurements of inflammatory responses (complement, neutrophil, monocyte, platelet activation, and the release of pro-inflammatory cytokines). It is anticipated that real-time measurement of the production of cytokine and complement concentration using the devices as described herein will correlate with measurements obtained by the conventional ELISA technique. More immediate measurements will aid in understanding the mechanisms of cellular activation, and modify surgical and perfusion protocols for minimizing the adverse effects of cardiopulmonary bypass. The proposed study is designed to develop a novel approach to measuring plasma cytokine and complement concentrations in a continuous real-time fashion within a microfluidic analytical system for online monitoring of inflammatory responses during CPB procedures. The microsystem includes a plasma autoseparation device and a novel microimmunoassay for continuous measurements. The measurement methods will use microfabrication technology to create blood carrying fluidic circuits and will be evaluated in a ex-vivo simulated cardiopulmonary bypass procedure with donor human blood. The microimmunoassay is based upon controlling the movements of immunoassay beads that will be passed through a series of flow streams including the plasma sample of interest with time varying cytokine and complement concentrations, washing solutions, secondary antibody solutions and a detection zone. Two designs will be evaluated. The first design uses magnetic beads whose movement is controlled by a magnetic field to pass between flow streams, while the second design uses a specially designed flow structure to allow the beads to pass between different flow streams without mixing or dilution.