Novel recombinant protein immunoassays for the diagnosis and monitoring of toxocariasis in children living in the United States.

用于诊断和监测美国儿童弓蛔虫病的新型重组蛋白免疫分析。

• 批准号: 10742436
• 负责人: Jill Elizabeth Weatherhead
• 金额: $ 8.03万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-16 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10742436
• 关键词: Achievement; Acute; Affect; Aftercare; Albendazole; Anthelmintics; Antibodies; Antigens; Asthma; Biological Assay; Black race; Blindness; C-Type Lectins; Canis familiaris; Characteristics; Child; Child Health; Childhood; Chronic Disease; Clinical; Development; Diagnosis; Diagnostic; Diagnostic tests; Disease; Enzyme Immunoassay; Enzyme-Linked Immunosorbent Assay; Eosinophilia; Epilepsy; Evaluation; Exposure to; Felis catus; Generations; Health Resources; Helminths; High Prevalence; Homologous Gene; Human; Immune response; Immunoassay; Immunodominant Antigens; Immunoglobulin G; Laboratories; Larva; Larva Migrans; Longitudinal cohort; Measures; Monitor; Morbidity - disease rate; Nematoda; Not Hispanic or Latino; Performance; Peripheral; Persons; Poverty; Recombinant Proteins; Recombinants; Reproducibility; Research; Seroprevalences; Specificity; Surveys; Syndrome; Technology; Time; Toxocara; Toxocara canis; Toxocariasis; United States; Western Blotting; Zoonoses; accurate diagnosis; cDNA Library; cost; diagnostic assay; eosinophil; health disparity; health economics; helminth infection; improved; innovation; novel; performance tests; prevent; public health intervention; response; socioeconomics; standard of care; treatment response; underserved community

Project Summary/Abstract Toxocariasis, caused by the dog and cat roundworm (Toxocara canis or T. cati), is the most common zoonotic helminth infection in children living in the United States (US). Toxocariasis disproportionately affects children from underserved communities in the US, with the highest prevalence of disease in non-Hispanic Black children (up to 21%). Toxocariasis manifests as distinct clinical syndromes leading to life-long morbidity from epilepsy, asthma, and blindness. Thus, toxocariasis is an important contributor to child health disparities in the US. Despite the significant life-long morbidity, toxocariasis remains underdiagnosed in the US in large part due to limitations of the standard-of-care Toxocara diagnostic assay, an enzyme immunoassay (EIA) that detects host antibody against T. canis excretory-secretory (TES) crude antigen. An improved Toxocara diagnostic assay would facilitate accurate diagnosis and evaluate treatment response in children to prevent life-long morbidity. Given the scalability and reproducibility, recombinant proteins are an exciting technology for improving Toxocara diagnostics. Our state-of-the art laboratory, which routinely creates recombinant proteins, generated a T. canis cDNA library to evaluate Toxocara antigens. Immunoscreening of the T. canis cDNA library with Toxocara infected human sera identified T. canis C-type lectins (Tc-CTL-1 and Tc-CTL-2) as the most immunodominant antigens. We subsequently identified the Tc-CTL-1 homolog in T.cati (Tca-CTL-1) with 93% sequence identity. Using recombinant protein technology, we developed a multiplex recombinant protein Luminex immunoassay and enzyme linked immunosorbent assay (ELISA) using Tc-CTL-1, Tc-CTL-2, Tca-CTL-1. The overall objective of this project is to evaluate the diagnostic performance and potential for post-treatment monitoring of two new multiplex immunoassays based on three, scalable recombinant proteins. We hypothesize that both multi-plex immunoassays, utilizing the three recombinant proteins (rTc-CTL-1, rTc-CTL-2 and rTca-CTL-1), will have improved test performance for diagnosis of toxocariasis compared to TES EIA and will permit the evaluation of anthelminthic treatment monitoring in children. To evaluate this hypothesis, we will first determine the performance characteristics of the two multiplex immuno-assays compared to TES EIA (standard of care) and TES-immunoblot (TES-Blot; gold standard). Second, using both immunoassays we will quantitate total IgG and IgG subtypes in peri-treatment sera collected from a longitudinal cohort of children with toxocariasis living in Houston, TX. Achievement of our aims will result in at least one accurate, low-cost, scalable multiplex immunoassay for the diagnosis and post-treatment monitoring of toxocariasis in children.

项目总结/摘要 弓蛔虫病，由狗和猫蛔虫（犬弓蛔虫或T。猫），是最常见的人畜共患病 生活在美国的儿童的蠕虫感染（US）。弓形虫对儿童的影响不成比例 来自美国服务水平低下的社区，非西班牙裔黑人儿童的患病率最高 (up 21%）。弓蛔虫病表现为不同的临床综合征，导致癫痫终身发病， 哮喘和失明因此，弓形虫是美国儿童健康差异的重要因素。尽管 由于存在严重的终身发病率，在美国，弓形虫病的诊断率仍然很低，这在很大程度上是由于局限性 标准治疗弓蛔虫诊断检测试剂盒，一种检测宿主抗体的酶免疫测定法（EIA）， 抗犬弓犬排泄分泌（TES）粗抗原。一种改进的弓首线虫诊断测定法， 促进儿童的准确诊断和评估治疗反应，以防止终身发病。给定 重组蛋白的可扩展性和可重复性是一种令人兴奋的技术，用于改善弓首线虫 诊断我们最先进的实验室，通常创造重组蛋白，产生了T。Canis cDNA文库以评估弓蛔虫抗原。T.犬弓形虫cDNA文库 感染的人血清鉴定为T.犬C型凝集素（Tc-CTL-1和Tc-CTL-2）为最具免疫显性的 抗原我们随后鉴定了猫弓蛔虫中的Tc-CTL-1同源物（Tca-CTL-1），其具有93%的序列同一性。 利用重组蛋白技术，我们建立了多重重组蛋白Luminex免疫分析方法 和使用Tc-CTL-1、Tc-CTL-2、Tca-CTL-1的酶联免疫吸附测定（ELISA）。总体目标 该项目的目的是评估两种新的诊断性能和治疗后监测的潜力。 基于三种可扩展的重组蛋白的多重免疫测定。我们假设这两个多功能 利用三种重组蛋白（rTc-CTL-1、rTc-CTL-2和rTca-CTL-1）的免疫测定将具有 与TES EIA相比，用于诊断弓形虫病的检测性能得到改善， 儿童驱虫治疗监测。为了评估这个假设，我们将首先确定 与TES EIA（护理标准）相比，两种多重免疫测定的性能特征， TES-免疫印迹（TES-印迹;金标准）。其次，使用两种免疫测定法，我们将定量总IgG和 从一个纵向队列的弓形虫病儿童中收集的治疗前后血清中的IgG亚型， 德克萨斯州休斯顿。我们的目标的实现将导致至少一个准确的，低成本的，可扩展的多路复用 免疫测定用于儿童弓形虫病的诊断和治疗后监测。