Molecular biological study of the pathogenesis of summer-type hypersensitivity pneumonitis

利用分子生物学资料，我们将夏季型过敏性肺炎（SHP）的病原体归为阿萨希丝孢酵母和粘状丝孢酵母。本研究应用聚合酶链反应（PCR）和Southern杂交技术，检测了SHP小鼠模型和患者支气管肺泡灌洗液（BALF）中抗原特异性DNA，以及患者家中空气中的抗原特异性DNA。吸入激发后6 h和96 h的BALF阳性率分别为100%和60%。18例患者入院后1周内BALF阳性率为94%。23例其他疾病患者和7例健康志愿者的阳性率分别为22%和29%。空气样品采用Andersen型小容量空气采样器采集。用超声波清洗器收集采样板上的颗粒物，PCR扩增，2/2的空气样品为阳性。利用PCR技术检测宿主和环境中的病原菌特异性DNA，可作为一种可扩展的方法，用于研究职业性微生物暴露引起的职业病的发病机制。

We assigned the causative agents of summer-type hypersensitivity pneumonitis(SHP) as Trichosporon asahii and T.mucoides, using molecular data. In this study, we applied polymerase chain reaction(PCR) and Southern hybridization to detect the antigen specific DNAs in the bronchoalveolar lavage fluid(BALF) of a murine model or patients with SHP, and in the air of patients' homes. BALF samples of the model were positive in 100% and 60% at 6h and 96h after the inhalation challenge, respectively. The BALF samples of 18 patients obtained within a week after admission were positive in 94%. Those of 23 patients with other diseases and 7 healthy volunteers were 22% and 29%, respectively. Air samples were collected by Andersen type low volume air sampler. Particles on the sampling plates were harvested by ultrasonic cleaner and amplified by PCR.The 2/2 air samples were positive. The each signal of T.asahii and T.mucoides were discriminated from the other fungi or human cells by PCR itself of additional restriction enzyme, Sau3AI.The detection of pathogen specific DNAs in host and environment by PCR would be an expandable method to investigate the pathogenesis of occupational diseases caused by microbial exposures.