Modifying consumptive coagulopathy following discordant porcine xenotransplantation - In vitro and in vivo analysis of enhanced HO-I expression on native and modified porcine cells and kidneys

项目四的目的是分析接触猪内皮后人凝血系统的异常激活。为此，对离体猪肾和肺灌注系统进行了修改，以便分析凝血激活参数。该项目将侧重于确定潜在的靶点，以药理学消除异常凝血。药物干预将使用不同的药物作用于不同水平的凝血过程，如Hirulog、活化蛋白C （APC）、前列环素和硝普塞。外源性重组APC可以替代无功能的猪凝血调节蛋白与人凝血酶的相互作用，后者在生理上产生APC。前列环素和硝普苷的作用是抑制人血小板聚集。在确定易受外源性药物干预的主要不相容后，通过rAAV介导的基因转移或基因工程引入适当的凝血级联调节因子，应该可以改变这些缺陷。最后，以某种方式表达人类凝血系统调节因子（如人类血栓调节蛋白或ho - 1）的多转基因猪器官将在灌注回路中测试其干扰这些系统中异常凝血激活的能力。

The aim of project IV is to analyse the aberrant activation of the human coagulation system following contact with porcine endothelium. For this purpose ex vivo porcine kidney and lung perfusion systems were modified to allow for analysis of coagulation activation parameters. The project will focus on the identification of potential targets for pharmacological abrogation of aberrant coagulation. Pharmacological intervention will be performed using different drugs acting at various levels of the coagulation process like Hirulog, activated protein C (APC), prostacyclin and nitroprusside. The administration of exogenous recombinant APC shall serve as a substitute for the non-functional porcine thrombomodulin to human thrombin interaction, which physiologically generates APC. Prostacyclin as well as Nitroprusside are aimed to cause inhibition of human platelet aggregation. Following identification of major incompatibilities susceptible to exogenous pharmacological intervention, alteration of these defects should be possible by introduction of appropriate human regulators of the coagulation cascade by rAAV mediated gene transfer or by genetic engineering. Finally, multi-transgenic porcine organs that had been engineered in a way to express human regulators of the coagulation system such as e.g. human thrombomodulin or HO-I will be tested in the perfusion circuits as to their ability to interfere with the aberrant coagulation activation in these systems.