High-throughput fluorescent multiplex array for indoor allergen exposure assessment

Abstract

Current enzyme immunoassay methods for detection of common indoor allergens in environmental dust samples are labor-intensive and time consuming. To develop and validate a fluorescent multiplex array to measure 6 (Der p 1, Der f 1, Der p 2, Der f 2, Fel d 1, and Can f 1) indoor allergen levels simultaneously. A multiplex array for 6 allergens, using mAbs covalently coupled to fluorescent microspheres, was developed using a single universal standard composed of purified natural allergens. The multiplex array was validated by comparing the measured dust mite, cat, and dog allergen levels in household dust samples to those obtained by standard ELISA methods. Linear regression analysis showed a highly significant quantitative correlation between the multiplex array and ELISA for dust mite, cat, and dog allergens: R(2) values ranging from 0.90 to 0.99 (P < .001). In addition, the sensitivity, limit of detection (<0.1 ng/mL), reproducibility, intra-assay coefficient of variance (<5%), and interassay coefficient of variance (<25%) of the fluorescent multiplex array were shown to be equal to or better than the ELISA method. A multiplex array has been developed to measure simultaneously 6 indoor allergens from a single sample. The array will facilitate epidemiologic studies and indoor air quality assessments and can, in principle, be expanded to include other allergens and biologics. The multiplex array lends itself to clinical studies, population-based environmental surveys, and allergen avoidance studies comparing allergen exposure in large populations over several time points.