NEW APPROACHES TO THE DIAGNOSIS OF AMEBIASIS

阿米巴病诊断新方法

• 批准号: 6362456
• 负责人: David M. Lyerly
• 金额: $ 29.76万
• 依托单位: TECHLAB, INC.
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-15 至 2002-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6362456
• 关键词: Entamoeba histolytica; amebiasis; communicable disease diagnosis; diagnosis design /evaluation; diarrhea; enzyme linked immunosorbent assay; gastrointestinal disorder diagnosis; monoclonal antibody; protozoal antigen; technology /technique development

Amebiasis, caused by Entamoeba histolytica, is a major problem in developing countries. In developed countries, it is most common in immigrants and travelers returning from the third world, and less common but present in men who have sex with men and immunosuppressed individuals. In previously sponsored SBIR research, we developed a stool antigen test for the detection of the E. histolytica adhesin, a protein that is an effective in vitro diagnostic marker. Our test, a microwell ELISA, is more accurate than microscopy and other commercial ELISAs, and more rapid than the "gold standard" culture/zymodeme, which takes 2 weeks to complete. We now have developed antigen affinity-purified antibody that has enabled us to increase the sensitivity' of the test ten-fold. We propose to use the improved antibody in dipsticks that can be used in the field as a rapid stool antigen test. In an effort to make immunoassays available to laboratories that test only fixed specimens (where most misdiagnosis of amebiasis occurs in the U.S.), we will develop immunoassays that detect formalin-stable Entamoeba antigens. We also propose to develop an antibody-based test for Entamoeba cysts. Polyclonal and monoclonal antibodies against cysts will be developed and used in screening immunoassays for contaminated water and food (recent food and water- borne outbreaks in Reston Virginia and Tblissi, Republic of Georgia respectively, make this a topical and immediate need). The development of cyst-specific tests will be patterned after those for the cyst- and oocyst- specific antigens of Giardia and Cryptosporidium. The data collected will be used to develop 510(k) documents for submission to and review by the FDA. This project will lead to a battery of tests that have broad application in the diagnosis of amebiasis. The tests will be crucial tools for evaluation of amebiasis vaccine candidates developed under our separate Tropical Disease Research Unit. PROPOSED COMMERCIAL APPLICATIONS: New diagnostic tests will be developed for amebiasis to solve the problems of misdiagnosis at community and reference labs in the U.S., enable screening of water supplies for the parasite, and to permit field evaluation of vaccine trials. Our results should lead to commercial tests that will be of significant value to the health industry around the world.

由溶组织内阿米巴引起的阿米巴病是发展中国家的一个主要问题。在发达国家，该病最常见于从第三世界返回的移民和旅行者，较少见，但存在于男男性行为者和免疫抑制个体中。在之前赞助的 SBIR 研究中，我们开发了一种粪便抗原测试，用于检测溶组织内阿米巴粘附素，这种蛋白质是一种有效的体外诊断标记物。我们的测试是微孔 ELISA，比显微镜和其他商业 ELISA 更准确，并且比“黄金标准”培养物/酶调制解调器更快，后者需要 2 周才能完成。我们现在已经开发出抗原亲和纯化的抗体，使我们能够将测试的灵敏度提高十倍。我们建议在试纸中使用改进的抗体，可在现场用作快速粪便抗原测试。为了使仅检测固定样本的实验室能够使用免疫测定（其中大多数阿米巴病误诊发生在美国），我们将开发检测福尔马林稳定的内阿米巴抗原的免疫测定。我们还建议开发一种基于抗体的内阿米巴包囊测试。将开发针对包囊的多克隆和单克隆抗体，并将其用于筛查受污染的水和食品的免疫测定（最近分别在弗吉尼亚州雷斯顿和格鲁吉亚共和国第比利西爆发食品和水源性疫情，这使得这成为一个热门和迫切的需求）。包囊特异性检测的开发将仿效贾第鞭毛虫和隐孢子虫的包囊和卵囊特异性抗原的检测。收集的数据将用于制定 510(k) 文件，提交给 FDA 并由 FDA 审查。该项目将带来一系列在阿米巴病诊断中具有广泛应用的测试。这些测试将成为评估我们独立的热带疾病研究单位开发的阿米巴病候选疫苗的重要工具。拟议的商业应用：将为阿米巴病开发新的诊断测试，以解决美国社区和参考实验室的误诊问题，能够筛查供水中的寄生虫，并允许对疫苗试验进行现场评估。我们的结果应该会带来商业测试，这对世界各地的健康产业具有重要价值。