title: Mechanism of occupational asthma due to western red cedar (Thuja plicata).
abstract: Occupational asthma due to Western red cedar is the most common form of occupational asthma in the Pacific Northwest and affects 4-13.5% of the exposed population. It has been shown to be caused by plicatic acid, a low molecular weight compound present uniquely in the wood. The mechanism of asthma induced by plicatic acid is not known, as specific IgG antibodies were found only in about 20% of patients. Sera from patients with red cedar asthma failed to passively sensitize human lung fragments of human basophils. Basophils from patients with this disease released histamine when challenged directly with plicatic acid in a specific manner. Immunologic mechanisms other than Type I hypersensitivity reaction are likely to be involved.
authors.affiliation: University of British Columbia, Department of Medicine, Vancouver General Hospital, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Chan-Yeung
mesh_terms: D000485:Allergens / Q000009:adverse effects* / Q000276:immunology; D000818:Animals; D000888:Antibodies, Anti-Idiotypic; D001249:Asthma / Q000209:etiology* / Q000276:immunology; D004391:Dust / Q000009:adverse effects*; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology; D017705:Lignans; D009284:Naphthols / Q000009:adverse effects* / Q000276:immunology; D009784:Occupational Diseases / Q000209:etiology* / Q000276:immunology; D014197:Trees; D014934:Wood
chemical_list: D000485:Allergens; D000888:Antibodies, Anti-Idiotypic; D004391:Dust; D017705:Lignans; D009284:Naphthols; D007073:Immunoglobulin E; C008938:plicatic acid