Inflammation and Repair as Determinants of Hemodialysis Fistula Maturation

描述(由申请人提供)：目前的估计表明，大约一半的动静脉瘘(AVF)在手术创建六个月后功能不成熟，无法正常用于血液透析。成熟的过程(及其失败)知之甚少，目前还没有有效的治疗方法来促进成熟。一项由NIDDK赞助的“血液透析内瘘成熟(HFM)”(U01 DK-082189-01)队列研究正在进行中，以检查接受动静脉瘘放置的患者的广泛的临床、人口统计学、生理和护理过程变量是否会影响动静脉瘘的成熟度和可用性。虽然母公司的研究将术前血管功能和静脉组织学特征与术后超声数据相关联，但其基本上是全球性的评估不会提供决定AVF成熟的局部和特定生物学机制的详细图景。因此，拟议的辅助临床研究检查了先前存在的内皮细胞和平滑肌细胞功能障碍、内皮修复和全身炎症之间的复杂相互作用。具体目标是(1)描绘AVF创建时供体静脉壁内内皮细胞和平滑肌细胞的全基因组表达模式，并确定与AVF外向重塑和血流速度变化相关的独特基因组模式(即“签名”)，(2)确定由循环内皮细胞(CEC)和内皮祖细胞(EPC)定义的静脉移植后内皮损伤和修复之间的初始和持续平衡，并获得与AVF成功或不成功相关的EPC的新的基因组“签名”，以及(3)评估全身炎症的作用，这是由循环单核细胞的全基因组表达模式决定的，因为它们与AVF成熟有关，可以用于预测结果和识别新的途径。我们建议进入佛罗里达大学的100名患者(50名患者测试集，50名患者验证集)，他们将参与父母研究。我们建议使用激光显微解剖技术捕获静脉壁内的内皮细胞和平滑肌细胞，以及使用新的专有Affymetrix HH/2外显子阵列对术前和术后第14天获得的血液内皮祖细胞和单核细胞进行宏观和新颖的微流控捕获技术，用于随后的全基因组表达分析。使用这些新技术，我们将实现两个主要目标：(1)从血管组织细胞群和丰富的血白细胞中开发新的基因组特征，用于预测成功的结果；(2)为治疗干预开发新的信号通路和潜在机制。拟议的研究将有效地利用母公司HFM研究中独特的数据收集工作，并增加对结果的预测性基因组建模，以及对AVF发育的生理学和病理生理学的重要机制洞察。

DESCRIPTION (provided by applicant): Current estimates suggest that approximately half of arteriovenous fistulas (AVF) fail to functionally mature and become regularly usable for hemodialysis by six months of surgical creation. The process of maturation (and its failure) is poorly understood, and no effective therapies to promote maturation are currently known. An NIDDK-sponsored "Hemodialysis Fistula Maturation (HFM)"(U01 DK-082189-01) cohort study is underway to examine whether a broad range of clinical, demographic, physiological and process-of-care variables in patients undergoing AVF placement influence maturation and usability of the AVF for dialysis. While the parent study will correlate pre-operative vascular function and venous histological features with post-operative ultrasound data, its largely global assessments will not furnish a detailed picture of the local and specific biological mechanisms that determine AVF maturation. Hence, the proposed ancillary clinical study examine the complex interplay between pre-existing endothelial and smooth muscle cell dysfunction, endothelial repair, and systemic inflammation. The specific objectives are (1) to delineate genome-wide expression patterns from endothelial and smooth muscle cells within the donor vein wall at the time of AVF creation, and to identify unique genomic patterns (i.e. "signatures") that are associated with AVF outward remodeling and changes in blood flow rate, (2) to determine the initial and ongoing balance between endothelial injury and repair following vein graft implantation, as defined by circulating endothelial cells (CECs) and endothelial progenitor cells (EPCs), and obtain novel genomic "signatures" of EPCs associated with a successful or unsuccessful AVF maturation, and, (3) to evaluate the role of systemic inflammation, as determined by genome-wide expression patterns of circulating monocytes, as they relate to AVF maturation and can be used to predict outcomes and identify novel pathways. We propose to enter 100 patients (50 patient test set, 50 patient validation set) at the University of Florida who will participate in the parent study. We propose to employ laser microdissection for endothelial and smooth muscle cell capture within the vein wall, as well as macro-scale and novel microfluidic capture technologies for blood EPCs and monocytes obtained preoperatively and on post-op day 14 for subsequent genome-wide expression analysis using a novel proprietary Affymetrix HH/2 exon array. Using these novel technologies, we will accomplish two major goals: (1) develop novel genomic signatures from vascular tissue cell populations and enriched blood leukocytes that can be used to predict a successful outcome, and (2) develop new insights into novel signaling pathways and potential mechanisms for therapeutic intervention. The proposed studies will effectively exploit the unique data collection effort in the parent HFM study and add both predictive genomic modeling of outcome, and significant mechanistic insight into the physiology and pathophysiology of AVF development.