Enzyme-linked immunosorbent assay specific for (1 -> 6) branched, (1 -> 3)-beta-D-glucan detection in environmental samples

(1 -->3)-beta -D-Glucans have been recognized as a potential causative agen t responsible for bioacrosol-induced respiratory symptoms observed in both indoor and occupational environments. A specific enzyme immunoassay was dev eloped to quantify (1 -->6) branched, (1 -->3)-beta -D-glucans in environme ntal samples. The assay was based on the use of a high-affinity receptor (g alactosyl ceramide) specific for (1 -->3)-beta -D-glucans as a capture reag ent and a monoclonal antibody specific for fungal cell wall P-D-glucans as a detector reagent. The assay, was highly specific for (1 -->6) branched, ( 1 -->3)-beta -D-glucans (such as that from Saccharomyces cerevisiae) and di d not show any response at 200 ng/ml to curdlan, laminarin, pustulan, dextr an, mannan, carboxymethyl cellulose, and endotoxins. The detection level wa s 0.8 ng/ml for baker's yeast glucan and Betafectin. A coefficient of varia tion of 7.8% was obtained for (1 -->3)-beta -D-glucans in house dust sample s. Metal working fluids spiked with (1 -->3)-beta -D-glucans inhibited the glucan assay. Because the assay is specific for (1 -->6) branched, (1 -->3) -beta -D-glucans and is sensitive and reproducible, it will be useful for t he investigation of health effects from exposure to this class of biologica lly active molecules.