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(申请人提供)：克氏锥虫是一种寄生虫，导致一种重要的人类疾病-恰加斯病，该疾病在美洲流行。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在疾病的急性期治愈，并在慢性期为患者提供好处，但很难实现治愈的认证。这种疾病的管理和监测在很大程度上取决于诊断工具的使用，这些工具基于对寄生虫蛋白质或蛋白质片段的循环抗体的检测。然而，尽管有一些诊断试验可用于筛查血库和诊断疾病，但这一领域仍有重大未得到满足的需求。目前还没有生物标志物可以区分不同寄生虫菌株的感染(这可能与药物敏感性和疾病预后有关)。此外，没有测试提供治疗成功或失败的早期迹象，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。近年来最有希望的发展之一是能够生产高密度多肽微阵列，这使得能够生产基本上完整的病原体蛋白质组的平铺展示。这项应用的目的是研究人类对这种寄生虫的抗体反应的复杂性，并识别数千种新的血清学标记以供进一步表征。使用覆盖完整克氏锥虫蛋白质组的高密度多肽微阵列，我们将从不同的恰加斯病患者群体中筛选血清，以识别这些免疫反应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记物：i)能够区分不同寄生虫谱系的感染，以及ii)能够预测治疗成功/失败。这些研究将为下游实验提供支持，这些实验将验证这些生物标记物，用于开发新的诊断工具。

 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.