Dot-blot assay for the semiquantitative detection of major dust mite allergens Derp1 and Derf1 in house dust

Mite allergens Derp1 and Derf1 were tested in 200 house dust samples using a nitrocellulose membranebased dot-blot assay. The assay enables the mite allergens in a dust extract to be detected with results that can be visually read semiquantitatively within 30 min. Positive results obtained with this method were easily observed as brown dots. The Derp1 and Derf1 allergens were also precisely quantitated by a two-site monoclonal antibody based enzyme-linked immunosorbent assay. Results of Derp1 and Derf1 mite allergens measured from the two methods were compared. The semiquantitative analysis using Spearman's correlation yielded a correlation coefficient of 0.892 (P < 0.01) for Derp1 and 0.872 (P < 0.01) for Derf1. The sensitivity, specificity and accuracy were 94.4%, 76.9% and 86.5% for Derp1 whereas the sensitivity, specificity and accuracy for Derf1 were 95%, 77% and 86%, respectively.