Immunoassay for diagnosis of Babesia infection

巴贝虫感染的免疫分析诊断

• 批准号: 8594221
• 负责人: Andrew E. Levin
• 金额: $ 30万
• 依托单位: IMMUNETICS, INC.
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-12-15 至 2015-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8594221
• 关键词: Antibodies; Antigens; Area; Babesia; Babesiosis; Bacteria sigma factor KatF protein; Biological Assay; Blood; Blood donor; Borrelia microti; Characteristics; Clinical; Clinical Trials; Complex; Development; Diagnosis; Diagnostic; Diagnostic tests; Disease; Enzyme Immunoassay; Enzyme-Linked Immunosorbent Assay; FDA approved; Immunoassay; Immunocompromised Host; Immunodominant Epitopes; Immunofluorescence Immunologic; Infection; Laboratories; Lead; Licensing; Microscopy; Open Reading Frames; Parasitic Diseases; Parasitic infection; Patients; Peptide Library; Peptides; Performance; Phase; Population; Procedures; Reporting; Risk; Sensitivity and Specificity; Series; Serum; Specificity; Staining method; Stains; Structure; Testing; Ticks; Transfusion; Validation; Vascular blood supply; Wit; base; clinical Diagnosis; improved; meetings; novel; pathogen; polypeptide; public health relevance; user-friendly

DESCRIPTION (provided by applicant): This project is aimed at development of an enzyme immunoassay (EIA) for antibodies to Babesia for use as a clinical diagnostic test. Babesiosis is an emerging tick-borne parasitic disease which may cause severe to fatal illness in immunocompromised or otherwise weakened patients, and may be carried in the blood subclinically in up to 1% of the population in endemic areas. Recent cases of fatal transfusion-transmitted babesiosis have also led to the identification of this pathogen as a significant threat to the blood supply. However, currently no commercial, validated and FDA approved tests are available for B. microti. Babesiosis is currently diagnosed by immunofluorescence staining, microscopy of blood smears, and/or PCR. None of these procedures are easily adaptable to routine clinical laboratory use. We propose to develop a microplate-based ELISA using novel synthetic B. microti antigens licensed to Immunetics that have previously been shown to be diagnostically significant markers. Specificity of the antigens will be assessed in blood donor sera from nonendemic areas and other controls. Assay performance will be evaluated on well-characterized sera from babesiosis patients from both U.S. Northeast and Midwest endemic regions. To identify immunodominant epitopes that may further improve assay sensitivity, we have identified a series of putative Babesia antigenic sequences that will be screened with babesiosis patient serum in an overlapping peptide library format, a strategy that has led to discovery of a number of antigens of diagnostic value. We also propose strategies to identify immunodominant epitopes of other pathogenic Babesia species, B. divergens/MO-1 and B. duncani/WA1. Novel immunodominant epitopes discovered through these strategies will be synthesized as peptide antigens with an appropriate structure for incorporation into current assay formats, which enable combination of multiple distinct peptides in a single-well assay. Once a single-well assay format is developed with sensitivity and specificity characteristics consistent with clinical diagnostic requirements, we will prepare for clinical trials and FDA submission in Phase II.

描述（由申请人提供）：该项目旨在开发用于Babesia抗体的酶免疫测定（EIA），以用作临床诊断测试。 Babesiosis是一种新兴的tick传播寄生疾病，可能在免疫功能低下或以其他方式削弱的患者中导致致命疾病严重，并且可以在流行地区多达1％的人口中属于血液中。最近致命输血传播的babesiosis病例也导致了这种病原体的鉴定为重大威胁 血液供应。但是，目前尚无商业，验证和FDA批准的测试可用于Microti。目前，通过免疫荧光染色，血液涂片显微镜和/或PCR诊断出Babesiosis。这些程序都不容易适应常规的临床实验室使用。我们建议使用新型的合成B. microti抗原开发基于微板的ELISA，这些抗原已获得了以前已被证明具有诊断出显着标记的免疫剂。抗原的特异性将在非流行区域和其他控制的血清中评估。测定性能将对来自美国东北和中西部地区的Babesiosis患者的特征性血清进行评估。为了鉴定可能进一步提高测定敏感性的免疫主导表位，我们已经确定了一系列推定的贝贝斯抗原序列，这些抗原序列将以重叠的肽库格式中的Babesiosis患者血清筛选，这是一种导致发现诊断值的许多抗原的策略。我们还提出了识别其他病原性贝贝斯物种的免疫主流表位，芽孢杆菌/mo-1和B. duncani/wa1的策略。通过这些策略发现的新型免疫主导表位将被合成为肽抗原，具有适当的结构，以掺入当前的测定格式中，这可以在单孔测定中组合多个不同的肽。一旦开发出具有与临床诊断要求一致的灵敏度和特异性特征的单孔测定格式，我们将准备临床试验和II期FDA提交。