An antigen-capture assay to screen donated blood for Babesia microti

项目摘要 在美国，每年约有5百万人接受输血。越来越多的人， 使其面临感染小巴氏杆菌的风险，小巴氏杆菌是一种存在于红血中的蜱传播的血液传播寄生虫 细胞（红细胞），并导致疾病巴贝西虫病。B。Microti对美国血液构成重大威胁 因为它在血库程序和储存条件下存活，并可通过输血传播。 输血传播的巴贝虫病（TTB）是造成输血相关性 向FDA报告的感染性死亡病例对于一种灵敏且 特异性，成本效益和高通量来筛选捐献的血液中的这种病原体。我们建议 开发一种能够检测血液中低水平寄生虫的基于EIA的抗原捕获测定法 可能不知道自己被感染的捐赠者（例如，无症状、慢性携带者）。我们产生了 使用B的抗体库。microti感染小鼠，然后筛选该文库以鉴定特异性抗体， 寄生虫表面表达/分泌的蛋白质。使用这些方法，我们已经鉴定出抗 七个B。microti蛋白在哺乳动物感染期间表达。在这项研究中，我们将产生一个优化的 使用针对一种或多种寄生虫分泌的/表面靶抗原的抗体对的抗原捕获测定， 在初步研究中已经确定。在特定目标1中，我们将优化捕获和报告抗体对 用于检测B的抗原捕获测定。microti，并确认特异性和敏感性 这些捕获-报告抗体对。在特定目标2中，我们将使用血液进行检测 从巴贝斯虫病患者中获得，并确定最终的抗原捕获测定以进行临床试验。 与我们的商业化合作伙伴在第二阶段应用中进行检测筛选。

PROJECT SUMMARY In the U.S. ~5 million individuals receive blood transfusions annually. Increasingly, these recipients are being put at risk of infection with Babesia microti, a tick-transmitted blood-borne parasite that resides in red blood cells (RBCs) and causes the disease babesiosis. B. microti represents a significant threat to the US blood supply as it survives blood banking procedures and storage conditions, and can be transmitted via transfusion. Transfusion transmitted babesiosis (TTB) is responsible for the highest percentage of transfusion-related infectious fatalities reported to the FDA. There is a critical unmet need for a method that is sensitive and specific, cost-effective, and high-throughput to screen donated blood for this pathogen. We propose the development of an EIA-based antigen-capture assay capable of detecting low levels of parasites in blood donors who are likely unaware that they are infected (e.g., asymptomatic, chronic carriers). We generated a library of antibodies using B. microti infected mice, and then screened this library to identify antibodies specific to parasite surface-expressed/secreted proteins. Using these methods, we have identified antibodies to seven B. microti proteins expressed during mammalian infection. In this study, we will generate an optimized antigen-capture assay using antibody pairs to one or more parasite secreted/surface target antigens that we have identified in preliminary studies. In Specific Aim 1, we will optimize capture and reporter antibody pairs for use in an antigen capture assay for the detection of B. microti, and confirm the specificity and sensitivity of these capture-reporter antibody pairs. In Specific Aim 2, we will performance our assay using blood obtained from patients with babesiosis, and identify a finalized antigen-capture assay to proceed to clinical assay screening with our commercialization partner in a phase II application.