Abstract
Respiratory symptoms and hypersensitivity pneumonitis (HP) among mushroom workers have been well
documented. Inhalation of shimeji mushroom (Tricholoma conglobatum) spore has been assumed to be
the cause of HP among
indoor shimeji cultivating workers. We isolated and partially characterized the allergenic components
of shimeji. The sera from 9 HP patients, 10 asymptomatic shimeji workers and 15 normal
individuals were examined for shimeji specific
lgG and lgA antibodies by ELISA using crude shimeji extract. Shimeji specific lgG- and lgA-
antibodies were higher in sera from HP patients than in sera from control subjects. Crude shimeji
spore extract was separated and purified by HPLC followed by SDS-PAGE, and their antigenic activity
was studied by immunoblotting with a pool of sera from patients. Sera from all HP patients showed
lgG and lgA antibody activities to 21, 16 and 14 kD proteins extracted from shimeji spore. The 21
kD protein contained internal peptide amino acid sequence of Gly-Gly-Thr-Val-lle-Asn-Leu-Leu-Gly,
Gln-Arg-Phe-Glu-Glu and Gln-Gly-lle-Tyr. These results demonstrate that shimeji spore extract
contains multiple proteinous components, which have antigenic activity to react with
the sera from HP patients among shimeji workers.
These proteins may be the potent sensitizing allergens to cause HP among shimeji cultivating
workers.
