Detection of cryptosporidium parvum by recombinant antibodies

重组抗体检测小隐孢子虫

• 批准号: 3467-2009
• 负责人: Lee, Hung
• 金额: $ 1.82万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2011
• 资助国家: 加拿大
• 起止时间: 2011-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=473717
• 关键词: Detection; cryptosporidium; parvum; recombinant; antibodies

The protozoan parasite Cryptosporidium parvum is an important and widely distributed pathogen causing the enteric illness cryptosporidiosis. When infective C. parvum oocysts are swallowed, they excyst into sporozoites which become attached to intestinal epithelial cells. Here, the parasites multiply by various sexual and asexual stages, and oocysts are formed and passed with feces. Cryptosporidiosis is an acute but self-limiting illness in immuno-competent patients who typically present with diarrhea, nausea, vomiting, abdominal cramps and fever. Immuno-compromised persons experience a more severe and chronic infection, which may lead to death. There is currently no known protective vaccine or treatment for cryptosporidiosis. Water is a common vehicle for transmission of Cryptosporidium spp. Routes of transmission for human cryptosporidiosis include zoonotic, environmental and person-to-person contact via the fecal-oral route. For the water industry, low-level contamination should at least indicate the need for caution and enhanced control measures. Assessing the threat of waterborne Cryptosporidium is complicated by the dynamic life cycle of the parasite itself. Even if oocysts are found in drinking water, it is difficult to determine their source, viability and infectivity towards humans. To implement an action level for Cryptosporidium, sensitive methods for detection and quantitation of infective oocysts in drinking water must be researched and brought into common use. The long term objective of our Cryptosporidium research program is to develop improved methods for the effective detection of Cryptosporidium. In the short term (5-year funding period of this grant), we plan to focus on the development, assessment and improvement of recombinant antibodies (rAbs) for detecting the presence as well as the viability and infectivity of Cryptosporidium oocysts. We will do this by selecting for, and improving the binding properties of, rAbs against several oocyst and sporozoite surface proteins. We will then test the ability of the rAbs to detect the presence of infective and viable C. parvum oocysts in water samples. Effective and early detection of C. parvum can ultimately lead to the safeguarding of drinking water supplies.

原生动物寄生虫小隐孢子虫是引起肠道疾病隐孢子虫病的重要且分布广泛的病原体。 当感染性小隐孢子虫卵囊被吞下时，它们会分泌成子孢子，子孢子附着在肠上皮细胞上。 在这里，寄生虫通过各种有性和无性阶段繁殖，形成卵囊并随粪便排出。 隐孢子虫病是免疫功能正常患者的一种急性但自限性疾病，通常表现为腹泻、恶心、呕吐、腹部痉挛和发烧。 免疫功能低下的人会经历更严重的慢性感染，这可能会导致死亡。 目前尚无已知的隐孢子虫病保护性疫苗或治疗方法。 水是隐孢子虫传播的常见媒介。 人类隐孢子虫病的传播途径包括人畜共患、环境传播和通过粪口途径的人与人接触。 对于水工业来说，低度污染至少表明需要谨慎和加强控制措施。 由于寄生虫本身的动态生命周期，评估水生隐孢子虫的威胁变得复杂。 即使在饮用水中发现卵囊，也很难确定其来源、活力和对人类的感染性。为了实施针对隐孢子虫的行动水平，必须研究用于检测和定量饮用水中感染性卵囊的敏感方法并将其投入普遍使用。 我们的隐孢子虫研究计划的长期目标是开发有效检测隐孢子虫的改进方法。 在短期内（本拨款的资助期为 5 年），我们计划重点开发、评估和改进重组抗体 (rAb)，用于检测隐孢子虫卵囊的存在以及活力和感染性。 我们将通过选择和改善 rAb 对几种卵囊和子孢子表面蛋白的结合特性来实现这一目标。 然后，我们将测试 rAb 检测水样中是否存在感染性和存活的微小念珠菌卵囊的能力。 对微小念珠菌的有效和早期检测最终可以保障饮用水供应。