HIGH-THROUGHPUT EPITOPE DISCOVERY: USE OF NEXT-GENERATION PEPTIDE CHIPS FOR FAST IDENTIFICATION AND FINE MAPPING OF DIAGNOSTIC AND PROGNOSTIC MARKERS FOR CHAGAS DISEASE

 描述（由申请人提供）：克氏锥虫是一种寄生虫，可引起美洲流行的一种重要人类疾病--恰加斯病。这种寄生虫通过昆虫叮咬、输血或器官移植传播。目前可用于治疗的药物能够治愈急性期的疾病，并为慢性期的患者提供益处，但难以获得治愈证明。这种疾病的管理和监测主要依靠诊断工具的使用，这些工具的基础是检测针对寄生虫蛋白或蛋白片段的循环抗体。然而，尽管有几种诊断测试可用于筛查血库和诊断疾病，但在这一领域仍有大量需求未得到满足。目前还没有生物标志物可以区分不同寄生虫株的感染（这可能与药物敏感性和疾病预后有关）。此外，没有提供治疗成功或失败的早期指示的测试，这构成了当前药物试验的主要障碍。需要源源不断的新生物标志物来探索它们开发新诊断工具的潜力。近年来最有前途的发展之一是生产高密度肽微阵列的能力，它允许生产基本上完整的病原体蛋白质组的平铺显示。本申请的目的是研究针对该寄生虫的人类抗体应答的复杂性，并鉴定数千种新的血清学标记物以进行进一步表征。使用覆盖完整克氏锥虫蛋白质组的高密度肽微阵列，我们将筛选来自不同恰加斯病患者群体的血清，以鉴定由这些免疫应答识别的所有抗体结合蛋白片段。这将提供一套全面的新型生物标志物。我们将通过两项比较研究来补充这一策略，在这两项研究中，我们将寻求定义生物标志物，i）能够区分不同寄生虫谱系的感染，ii）能够预测治疗成功/失败。这些研究将提供一系列下游实验，这些实验将验证这些生物标志物，以开发新的诊断工具。

 DESCRIPTION (provided by applicant): Trypanosoma cruzi is a parasite responsible for an important human disease, Chagas Disease, which is endemic in the Americas. The parasite is transmitted by the bite of an insect, or by blood transfusion or organ transplants. The current drugs available for treatment are able to cure the disease in its acute phase, and provide benefits to patients in the chronic stage, but certification of cure is difficult to achieve. Management and surveillance of this disease rests heavily on the use of diagnostic tools, which are based on the detection of circulating antibodies against parasite proteins or protein fragments. However, in spite of the availability of a few diagnostic tests for screening blood banks, and for diagnosing the disease, there are major unmet needs in this area. There are currently no biomarkers that can differentially diagnose infections by different parasite strains (which could be linked to drug sensitivity and disease prognosis). Also, there are no tests that provide an early indication of therapeutic treatment success or failure, which constitutes a major obstacle in current drug trials. A constant stream of new biomarkers is required to explore their potential to develop new diagnostic tools. One of the most promising developments in recent years is the ability to produce high-density peptide microarrays, which allow the production of tiling displays of essentially complete pathogen proteomes. The goal of this application is to study the complexity of the human antibody response against this parasite, and to identify thousands of novel serology markers for further characterization. Using high-density peptide microarrays covering the complete Trypanosoma cruzi proteome we will screen sera from diverse Chagas Disease patient populations to identify all antibody- binding protein fragments recognized by these immune responses. This will provide a comprehensive set of novel biomarkers. We will complement this strategy with two comparative studies in which we will seek to define biomarkers that i) are able to differentiate infection by different parasite lineage, and ii) are able to predict treatment success/failure. These studies will feed a pipeline of downstream experiments which will validate these biomarkers for the development of new diagnostic tools.