DIFFERENCES IN THE PROTEIN SIGNATURES/PNH PLATELETS

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 阵发性睡眠性血红蛋白尿是一种获得性溶血性贫血，其特征是红细胞对补体的敏感性增加，导致血管内溶血和血红蛋白尿。 PNH 是由于 X 连锁 PIGA 基因发生突变的细胞克隆的扩增所致。 PIGA 是合成糖基磷脂酰肌醇 (GPI) 锚分子所必需的酶亚基。因此，源自突变祖细胞的血细胞缺乏所有 GPI 锚定分子。我们研究的广泛长期目标是了解 PNH 的病理生理学和发病机制。 PNH 是一种慢性疾病，通常与较高的发病率和死亡率相关。血栓形成是最常见的死亡原因。 PNH 血栓形成的病理生理学尚不清楚。我们认为，缺乏 GPI 相关蛋白（PNH 表型）的血小板 (Plt's) 在 PNH 血栓形成的发病机制中发挥着重要作用。我们假设具有 PNH 表型的血细胞不仅缺乏所有 GPI 连接蛋白，而且还缺乏其他蛋白质，这些蛋白质的合成或定位依赖于正常的 GPI 锚定生成，并且 Plt 上这些蛋白质的缺乏可能会导致血栓形成风险。在拟议的研究中，我们将通过鉴定与 PNH 相关的 PNH Plt 中的蛋白质和蛋白质修饰来关注这些假设的分子方面。首先，我们将开发可重复的蛋白质组学程序来分离和分析来自正常和 PNH 患者的 Plt，然后将缺乏 GPI 连接蛋白的 Plt 的蛋白质谱与正常 Pit 的蛋白质谱进行比较。最后，我们将开发检测和测量 PNH 细胞特异性候选蛋白或蛋白修饰的检测方法，并验证第二组患者和对照个体中候选蛋白的差异表达。我们提出的研究可能会发现一些意想不到的蛋白质、蛋白质相互作用和蛋白质修饰，这些可能会显着促进我们对 PNH 血栓形成发病机制的理解，也可能在其他情况下，其中异常克隆造血与血栓形成相关，例如真性红细胞增多症或其他骨髓增殖综合征。分析和比较健康和疾病中血小板蛋白质组的既定方法可能会导致鉴定新的生物标志物，这些生物标志物可用于评估血栓形成的风险或确定诊断或药物开发的新靶标。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Paroxysmal nocturnal hemoglobinuria is an acquired hemolytic anemia characterized by the increased sensitivity of red cells to complement leading to intravascular hemolysis and hemoglobinuria. PNH is due to the expansion of a cell clone that has acquired a mutation in the X-linked PIGA gene. PIGA is an enzyme subunit essential for the synthesis of glycosyl phosphatidylinositol (GPI) anchor molecules. Blood cells derived from the mutant progenitor cell are therefore deficient in all GPI-anchored molecules. The broad long-term objective of our research is to understand the pathophysiology and pathogenesis of PNH. PNH is a chronic disease often associated with substantial morbidity and mortality. Thrombosis is the most frequent cause of death. The pathophysiology of thrombosis in PNH is not understood. We propose that platelets (Plt's) deficient in GPI-linked proteins (PNH phenotype) play a major role in the pathogenesis of thrombosis in PNH. We hypothesize that blood cells with the PNH phenotype not only lack all GPI-linked proteins, but are also deficient in other proteins, whose synthesis or localization is dependent on normal GPI anchor production, and that the deficiencies of these proteins on Plt's might contribute to the prothrombotic risk. In the proposed research we will focus on the molecular aspects of these hypotheses by identifying proteins and protein modification in PNH Plt's that are associated with PNH. First, we will develop reproducible proteomic procedures to isolate and analyze Plt's from normal and PNH patients, and then compare the protein profile from Plts' deficient in GPI-linked proteins with the protein profile of normal Pit's. Finally, we will develop assays to detect and measure candidate proteins or protein modifications specific for PNH cells and verify the differential expression of candidate proteins in a second cohort of patient and control individuals. Our proposed investigations are likely to identify a number of unanticipated proteins, protein interactions, and protein modifications that might significantly advance our understanding of the pathogenesis of thrombosis in PNH and possibly also in other conditions, in which an abnormal clonal hematopoiesis is associated with thrombosis, for example, polycythemia vera or other myeloproliferative syndromes. Established methods for analyzing and comparing the platelet proteome in health and disease might lead to the identification of novel biomarkers useful in evaluating the risk of thrombosis or identify new targets for the development of diagnostics or drugs.