Identification of allergens involved in occupational asthma due to carminedye

Background: Carmine has been implicated as an etiologic agent of occupation al asthma, but the allergens involved have not been yet identified. Objective: To identify the allergens involved in occupational asthma due to carmine dye. Methods: An in vitro study based in SDS-PAGE and IgE immunoblotting with ca rmine and cochineal extracts was performed. Sera from three carmine dye wor kers diagnosed with occupational asthma induced by carmine dye and from sev en nonatopic subjects were used. Results: Three proteins of around 30, 28, and 17 kD in raw cochineal extrac t and another protein of 50 kD in the boiled one were demonstrated by SDS-P AGE. Two proteins of around 50 and 28 kD were observed in the carmine extra ct by the same technique. Specific IgE binding bands at 17 kD in cochineal raw extract, at 50 kD in the boiled one, and at 28 kD in carmine extract we re demonstrated by IgE immunoblotting. Conclusions: We have identified three allergens of around 17, 28, and 50 kD implicated in occupational asthma of three carmine workers.