Development of an ELISA system for diagnosis of summer-type Hypersensitivity pneumonitis and the evaluation of its clinical usefulness

夏季型超敏性肺炎（SHP）是日本最常见的超敏性肺炎。其主要的致病抗原生物是毛丝虫病种（阿萨希T.和粘液T.）。对SHP的诊断有重要意义的是要证实患者血清中有针对致病抗原的特异性抗体，因为特异性抗体的存在表明患者曾暴露于该抗原并对其致敏。因此，我们试图建立一个三明治酶联免疫吸附试验（ELISA）系统，以评估患者血清样品中的特异性抗体活性。在本研究中，我们设计了一种ELISA系统，使用日本血吸虫特异性单克隆抗体来检测日本血吸虫的抗体。我们通过使用SHP患者、其他肺部疾病患者或健康志愿者的血清来评估该系统的有效性。我们发现该系统的特异性和敏感性分别为92.8%和92.3%。结果表明，该系统可用于小功率热泵的诊断。

Summer-type hypersensitivity pneumonitis (SHP) is the most prevalent type of hypersensitivity pneumonitis in Japan. Its main causative antigenic organisms are Trichosporon species (T. asahii and T. mucoides). It is important in diagnosing SHP to prove specific antibody against causative antigen in patient's serum, for the existence of specific antibody indicates the patient had been exposed to, and sensitized to the antigen. Therefore, we attempted to establish a sandwich enzyme-linked immunosorbent assay (ELISA) system which enable evaluation of specific antibody activity in patients' serum samples.In the present study, we devised an ELISA system using monoclonal antibody specific to T. asahii, to measure antibodies against T. asahii. We evaluated the usefulness of the system by using sera from patients with SHP, patients with other pulmonary diseases, or healthy volunteers. We found specificity and sensitivity of the system were 92.8% and 92.3%, respectively. This system was proved to be useful in diagnosing SHP.