Optimization of the measurement of outdoor airborne allergens using a protein microarrays platform

Abstract

Increased knowledge on allergenic molecules in the environmental air helps in the information on environmental air quality and in the prevention and treatment of allergies. The aim of this study is to develop and validate a new methodology for the simultaneous detection and quantification of several airborne allergens using protein microarray technology, which has been created for the clinical detection of allergens. The immunological method was performed with Immuno Solid-phase Allergen Chip (ISAC) inhibition assay. Reagents for the validation studies include the following: (1) three sera from patients allergic to grass pollen each with different IgE levels as the detection reagents, (2) recombinant Phl p 1 major allergen as the inhibitor for the inhibition assays, (3) “natural” Phl p 1 released by Phleum pratense (timothy grass) pollen grains as the “biologically” relevant aeroallergen and (4) samples of airborne pollens collected by a Multi-vial Cyclone Sampler for comparison of levels of pollen detection versus the protein allergen detection by the microarray assay. The results obtained showed that ISAC inhibition is a sensitive technique able to detect 2.1 pg/mL of Phl p 1 and the allergens released from 1 grain of natural pollen. Also, the airborne allergen samples analyzed showed a good correlation with the concentration of grass pollen in the air. The use of ISAC inhibition will greatly improve future airborne simultaneous allergen quantification, becoming a valuable option in air quality control.