|Budget Amount *help
¥8,800,000 (Direct Cost : ¥8,800,000)
Fiscal Year 1998 : ¥1,800,000 (Direct Cost : ¥1,800,000)
Fiscal Year 1997 : ¥1,800,000 (Direct Cost : ¥1,800,000)
Fiscal Year 1996 : ¥5,200,000 (Direct Cost : ¥5,200,000)
Previously, we reported that the genus Trichosporon was a major causative agent of summer-type hypersensitivity pneumonitis(SHP), the most prevalent type of hypersensitivity pneumonitis (HP) in Japan. In this study, we re-valued three antigenic types within the genus Trichosporon as the causative agents of SHP.Corresponding standard strains, TIMM 1573 (serotype I), TIMM 1318 (serotype II), and M9456 (serotype III) were assigned to species T.mucoides, T.asahii and T.motevideense, respectively, based on 95% or more DNA/DNA relatedness with each type of culture and other genetical, physiological and morphological characteristics. To confirm the significance of these serotypes, 98 other strains of Trichosporon isolated from patients' environments and 24 CBS strains, including type cultures of species described within the genus, were serotyped. Serum antibody analysis of 220 SHP patients against Trichosporon spp. were also examined to estimate the antigenic profile of SHP.The present result
s indicate that T.asahii and T.mucoides, which are the most common causes of trichosporonosis, appear to be the major causative agents of SHP.We also 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 6 and 96 h after the inhalation challenge, respectively. The BALF samples of 18 patients obtained within 1 week after admission were positive in 94%. Those of 23 patients with other diseases and seven Healthy, volunteers were 22 and 29%, respectively. Air samples were collected by an Andersen type low volume air sampler. Particles on the sampling plates were harvested by a ultrasonic cleaner and amplified by PCR.The 2/2 air samples were positive. The signal of each of T.asahii and T.mucoides were discriminated from the other fungi or human cells by PCR itself or the additional restriction enzyme, Sau3 AI.The detection of pathogen specific DNAs in the host and in the environment by PCR would be an expandable method for the investigation of the pathogenesis of occupational diseases caused by microbial exposures.