Inflammation of reperfused heart: gene deletion

项目2：再灌流小鼠心脏的炎症：基因缺失项目2的主题仍然是心肌缺血后调节心脏内白细胞运输的细胞和分子机制的定义。我们和其他人对细胞黏附分子缺陷小鼠的研究和鉴定清楚地表明，调节白细胞运输的分子机制既是刺激的，也是组织特异性的。最近在利用CAMS缺乏的小鼠进行的小鼠缺血/再灌注模型中的研究表明，可以利用不同的途径来使白细胞外溢。在这一应用中，我们将继续追求分子遗传学的方法，但重点已从研究白细胞在加强缺血/再灌注后心肌细胞损伤中的作用转移到了解缺血损伤后控制白细胞在心脏中渗透的独特分子机制以及细胞黏附分子在缺血损伤后心脏愈合中的作用。提出了以下具体目标：1)利用细胞黏附分子缺陷的小鼠和封闭的单抗，确定心脏特异的分子机制，调节缺血损伤后再灌注和再灌注后白细胞的转运。2)通过检测小鼠心脏微血管内皮细胞和下腔静脉内皮细胞的表型和功能差异来表征组织特异性的潜在机制，并通过在最近建立的小鼠慢性闭合胸缺血再灌注模型中全面分析缺血损伤后心脏中细胞因子、趋化因子及其受体的表达水平来探索刺激特异性的潜在机制；3)表征和鉴定IL-4诱导的一种新的白细胞与内皮细胞黏附的新途径的分子机制，该途径不依赖于E-、P-和L-选择素；4)在慢性存活的心肌梗死小鼠模型中，利用细胞黏附分子缺陷的小鼠，明确细胞黏附分子在调节心肌缺血损伤后修复和重塑中的作用。

PROJECT 2: Inflammation of Reperfused Mouse Heart: Gene Deletion The theme of Project 2 continues to be the definition of the cellular and molecular mechanisms that regulate leukocyte trafficking in the heart after myocardial ischemia. Development and characterization of mice deficient in cell adhesion molecules by ourselves and others have clearly demonstrated that the molecular mechanisms that regulate leukocyte trafficking are both stimulus and tissue specific. Recent studies in the mouse model of ischemia/reperfusion using mice deficient in CAMs have shown that alternative pathways can be utilized for leukocyte extravasation. In this application we will continue to pursue a molecular genetic approach, but the focus has shifted away from studying the role of leukocytes in potentiating injury to myocytes after ischemia/reperfusion to understanding the unique molecular mechanisms that control leukocyte infiltration in the heart after ischemic injury and the role of cell adhesion molecules in healing of the heart after ischemic injury. The following specific aims are proposed: 1) define cardiac-specific molecular mechanisms that regulate leukocyte trafficking with and without reperfusion after ischemic injury using mice deficient in cell adhesion molecules along with blocking monoclonal antibodies. 2) characterize potential mechanisms for tissue specificity by examining phenotyping and functional differences between murine cardiac microvascular endothelial cells and murine endothelial cells from the inferior vena cava, and explore potential mechanisms for stimulus specificity by comprehensively profiling mRNA levels for cytokines, chemokines, and their receptors in the heart after ischemic injury with and without reperfusion in a recently developed chronic closed chest model of murine ischemia and reperfusion; 3) characterization and identification of the molecular mechanisms for a novel pathway for the primary adhesion of leukocytes to endothelial cells that is induced by IL-4 and is independent of E-, P-, and L-selectin; 4) definition of the role of cell adhesion molecules in regulating repair and remodeling of the heart after ischemic injury by using mice deficient in cell adhesion molecules in the mouse model of myocardial infarction with chronic survival.