Optimization of antigen preparations from Coccidioides for diagnostic testing

用于诊断测试的球孢子菌抗原制剂的优化

• 批准号: 10310506
• 负责人: Thomas E Grys
• 金额: $ 21.56万
• 依托单位: MAYO CLINIC ARIZONA
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-12-01 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10310506
• 关键词: Acute; Acute Disease; Anti-Bacterial Agents; Antibodies; Antibody Response; Antifungal Agents; Antigens; Biological Assay; Biology; California; Caring; Chitinase; Clinical; Clinical Sensitivity; Coccidioides; Coccidioidomycosis; Complement; Confusion; Detection; Diagnosis; Diagnostic; Diagnostic tests; Disease; Early Diagnosis; Enzyme Immunoassay; Fungal Antigens; Goals; Grant; Health Personnel; Human; Immunodiffusion; Immunoglobulin G; Individual; Infection; Inhalation; Laboratories; Lung; Malignant Neoplasms; Measures; Organism; Outcome; Patients; Performance; Persons; Pharmaceutical Preparations; Preparation; Proteins; Proteome; Proteomics; Publishing; Recombinants; Reproduction spores; Research Proposals; Sampling; Serodiagnoses; Serology; Serology test; Serum; Soil; Structure of parenchyma of lung; Symptoms; System; Testing; Time; Translating; Uncertainty; Viral; Work; Yeasts; antibody detection; antigen diagnostic; antimicrobial; base; clinical decision-making; community acquired pneumonia; desert fever; diagnostic strategy; disease diagnosis; fungal pneumonia; fungus; human disease; improved; in vivo; insight; sample fixation; seropositive; side effect

Summary: Coccidioidomycosis (Valley Fever, “VF”) is caused by a soil-dwelling fungus endemic to the southwestern U.S. and central valley in California. The Coccidioides fungus is a dimorphic organism with a mycelial form in soil and spherules (a yeast-like form) in a human host. When soil is disrupted, mycelial spores become airborne and can be inhaled into lungs where they transform into spherules. As spherules burst they release endospores, each of which can grow into a new spherule. Fungal pneumonia may mimic cancer or other community acquired pneumonias (bacterial and viral), but should be recognized as fungal and treated differently. Current diagnostic tests rely on a serologic (antibody) response to fungal antigens. For over 50 years, antigen preparations for detecting antibodies in patients suspected of having Valley Fever have been derived from mycelia which is rich with an antigen called CF (also called CTS-1 or chitinase-1). Serologic assays may be performed by enzyme immunoassay, immunodiffusion or a complement fixation assay to detect antibodies against the fungus. The clinical problem is that approximately 30-50% of patients who are acutely ill initially test sero- negative using current tests, leading to inappropriate treatment. We suggest that one of the reasons for sero-negativity is that mycelial antigen preparations, not spherule antigens, are used for detection of patient antibodies. Since spherules, not mycelia, are what grow in a host, we hypothesize that patients are more likely to make antibodies to antigens predominantly in spherules, the form that grows in the host. In fact, our analysis of the proteomes of Coccidioidal spherules and mycelia demonstrated that the CF (CTS-1, chitinase-1) antigen is highly expressed in mycelia, but not spherules (CF levels are 70-fold higher in mycelia than spherules). Continued proteomic analysis revealed that several other proteins are more highly expressed in spherules than mycelia. The objectives of this grant are to test sero-negative, sero-positive and control patient sera for reactivity and titers against 3 recombinant spherule proteins and to compare titers to commercially available antigen preparations. If sero-negative and sero-positive patient sera are more reactive with spherule antigens alone–or spiked into current diagnostic antigen preparations, this work could translate into a more sensitive, reliable, and consistent antigen preparation for accurate serologic diagnosis of patients with Valley Fever.

总结： 球孢子菌病（山谷热，“VF”）是由一种土栖真菌引起的， 美国西南部和加州的中央谷。球孢子菌属真菌是一种二型 在土壤中以菌丝体形式存在，在人类宿主中以小球（类似酵母的形式）存在的有机体。当 土壤被破坏，菌丝孢子成为空气传播，并可吸入肺部， 变成小球当小球破裂时，它们释放出内生孢子， 变成一个新的小球真菌性肺炎可能与癌症或其他社区获得性肺炎相似。 肺炎（细菌性和病毒性），但应被视为真菌和不同的治疗。 目前的诊断试验依赖于对真菌抗原的血清学（抗体）反应。为 50多年来，用于检测疑似患有 山谷热源自菌丝体，其富含称为CF的抗原（也称为抗原）。 称为CTS-1或几丁质酶-1）。血清学测定可以通过酶免疫测定进行， 免疫扩散或补体结合测定以检测针对真菌的抗体。的 临床问题是，大约30-50%的急性病患者最初检测血清- 使用当前的测试呈阴性，导致不适当的治疗。 我们认为，血清阴性的原因之一是菌丝抗原， 使用制剂而不是小球抗原来检测患者抗体。以来 球体，而不是菌丝体，是在宿主体内生长的，我们假设病人更多的是 可能主要在小球体中产生针对抗原的抗体，这种形式生长在 主持人事实上，我们对球孢子球和菌丝体蛋白质组的分析 表明CF（CTS-1，几丁质酶-1）抗原在菌丝体中高度表达，但不表达。 小球（菌丝体中的CF水平比小球高70倍）。连续蛋白质组学 分析显示，其他几种蛋白质在小球中的表达比在 菌丝体 这项补助金的目的是测试血清阴性，血清阳性和控制病人 血清对3种重组小球蛋白的反应性和滴度，并将滴度与 市售抗原制剂。如果血清阴性和血清阳性患者血清 与单独的小球抗原或掺入当前诊断抗原中的小球抗原反应性更强 因此，这项工作可以转化为更敏感，可靠和一致的抗原 为准确诊断山谷热患者做好准备。