Dispersion of horse allergen in the ambient air, detected with sandwich ELISA

Abstract

We have developed a sensitive, horse-allergen-specific, mAb assay allowing detection of low levels of horse allergens. Raised levels of horse allergen were found outdoors only in the close vicinity of the stable.

Air Quality in Horse Stables

“…In Sweden, the official recommendation since 1989 is 500m (National board of housing, building and planning 1998), but not much was known about dispersion of horse allergen in ambient air at that time and no assays were available for detection of horse allergen. Later studies have shown that horse allergens do not disperse more than about 50-100m from source, which is from stables and fields where horses are kept (Emenius et al, 2001;Elfman et al, 2008). On days with increased wind speed and with prevailing winds, horse allergen levels can sometimes be detected up to 200-450m from the source.…”

Detection of Horse Allergen around a Stable

“…The extract was aliquoted and stored as a 1/5 dilution with thimerosal at 4–8°C. To compare levels of horse allergen (Allergon) with an earlier study [7] the standard was set to a horse standard from NIBSC (National Institute for Biological Standards and Control, UK). Protein in both standards were determined with the Micro BCA protein assay reagent kit (Pierce Chemical Company, USA) using BSA as a standard.…”

“…The assay was basically performed according to the protocol published by Emenius et al [7] (reagents were generously supplied by Mabtech, Stockholm, Sweden), except for the different horse allergen standard used in this study. The standard curve range was 2–64 U/ml.…”

“…There were no data available on the spread of horse allergen when this distance was set and it has been questioned in township planning. A previous study conducted in a densely built-up area showed that airborne horse allergen spread no further than 20–40 m from a stable [7]. …”

“…Exposure to horse allergens can occur directly through horse riding or indirectly through the transport of allergens in the ambient air from stables [7] or by means of transfer on clothes or hair to public environments [8,9,10,11]. …”