Coagulation Control To Protect Gaitko Lung and Liver Xenografts

当使用GalTKO器官时，心脏和肾脏的超急性排斥反应被可靠地预防 另外表达人补体途径调节蛋白(HCPRP)。相比之下，尽管 与GalTKO或hCPRP肺相比，猪肺异种移植功能显著延长， 尽管如此，肺损伤仍会在移植到狒狒体内或在灌流后数小时内发生 人血。同样，当GalTKO.hCPRP猪的肝脏出现血小板隔离时，几乎立即发生 被原位移植到狒狒体内，限制了接受者的存活率。 猪内皮细胞膜糖蛋白与猪血管内皮细胞膜糖蛋白的分子不相容 灵长类血小板受体和血浆凝血途径蛋白可能解释了 异种肺和肝移植损伤中凝血途径紊乱和血小板滞留。这些 不相容也可能导致心脏和肾脏异种移植的相关问题，血栓 微血管病(TM)和消耗性凝血病(CC)。 在这个项目中，我们将利用GalTKO.hCPRP猪肺对血小板的特殊亲和力 以及中性粒细胞的隔离，以及它放大凝血途径激活的倾向。使用 结合临床可用的方法来影响血栓调节(DDAVP，以耗尽供体vWF 移植前；唾液酸酶抑制剂扎那米韦维持循环血小板上唾液酸的表达 受体和相关的vWF)和独特的分子靶向试剂(抗GPlB Fab和抗唾液酸酶 抗体)，目标1将检验GPlB/vWF受抑制调节的假说 猪内皮细胞对灵长类血小板和中性粒细胞的隔离。在Aim 2中，GalTKO.hCPRP猪肺 也表达人类凝血酶途径调节蛋白(血栓调节蛋白或内皮蛋白C 受体)将揭示这一途径中的分子不相容是否对肺有显著贡献 损伤，以及这些分子的表达是否具有保护性。目标3将决定战略是否 由AIMS 1和AIMS 2产生，将始终如一地产生企鹅的猪肺的维持生命的功能，以及 在GalTKO.hCPRP支持下，是否有类似的方法可靠地预防狒狒的血小板减少症 猪肝。

Hyperacute rejection ofthe heart and kidney is reliably prevented when GalTKO organs are used that additionally express a human complement pathway regulatory protein (hCPRP). In contrast, although GalTKO.hCPRP pig lung xenograft function is significantly prolonged relative to GalTKO or hCPRP lungs, lung injury nonetheless occurs within hours of transplantation into baboons or following perfusion with human blood. Similarly, platelet sequestration occurs almost immediately when GalTKO.hCPRP pig livers are orthotopically transplanted in baboons, and limits recipient survival. A number of molecular incompatibilities between pig endothelial membrane glycoproteins and primate platelet receptors and plasma coagulation pathway proteins probably explain the mechanistic basis of coagulation pathway dysregulation and platelet sequestration in lung and liver xenograft injury. These incompatibilities may also contribute to related problems in heart and kidney xenotransplants, thrombotic microangiopathy (TM) and consumptive coagulopathy (CC). In this Project we will take advantage ofthe GalTKO.hCPRP pig lung's particular avidity for platelet and neutrophil sequestration, and its propensity to amplify coagulation pathway activation. Using a combination of clinically available approaches to impact thromboregulation (DDAVP, to deplete donor vWF pretransplant; zanamivir, a sialydase inhibitor, to maintain sialic acid expression on circulating platelet receptors and associated vWF) and unique molecular targeting reagents (an anti-GPlB Fab and an antisialydase antibody), Aim 1 will test the hypothesis that GPlB/vWF, modulated by desialydation, mediate primate platelet and neutrophil sequestration by porcine endothelium. In Aim 2, GalTKO.hCPRP pig lungs that also express human thrombin pathway regulatory proteins (thrombomodulin or endothelial protein C receptor) will reveal whether molecular incompatibilities in this pathway contribute significantly to lung injury, and whether expression of these molecules is protective. Aim 3 will determine whether strategies arising from Aims 1 and 2 will consistently yield life-supporting function of a pig lung in a baboon, and whether a similar approach reliably prevents thrombocytopenia in a baboon supported by a GalTKO.hCPRP pig liver.