Diagnostic characterization of respiratory allergies by means of a
multiplex immunoassay.
Abstract
Allergic sensitization is commonly assessed in patients by performing
the skin prick test (SPT) or determining specific IgE levels in blood
samples with the ImmunoCAP assay, which measures each allergen and
sample separately. This paper explores the possibility to investigate
respiratory allergies with a high throughput method, the Meso Scale
Discovery (MSD) multiplex immunoassay, measuring IgE levels in low
volumes of blood. The MSD multiplex immunoassay, developed and optimized
with standards and allergens from Radim, was validated against the SPT
and the ImmunoCAP assay. For 18 adults (15 respiratory allergy patients
and 3 controls), blood collection and the SPT were performed within the
same hour. Pearson correlations and Bland-Altman analysis showed high
comparability of the MSD multiplex immunoassay and the ImmunoCAP assay,
except for house dust mite. The sensitivity of the MSD multiplexed assay
was ≥75% for most allergens compared to the SPT and ImmunoCAP assay.
Additionally, the specificity of the MSD multiplex immunoassay was ≥80%
- the majority showing 100% specificity. Only the rye allergen had a
low specificity when compared to the SPT, probably due to
cross-reactivity. The reproducibility of the MSD multiplex immunoassay,
assessed as intra- and inter-assay reproducibility and biological
variability between different sampling moments, showed significantly
high correlations (r=0.943-1) for all tested subjects (apart from
subject 13; r=0.65-0.99). The MSD multiplex immunoassay is a
reliable method to detect specific IgE levels against respiratory
allergens in a multiplexed and high throughput way, using blood samples
as small as from a finger prick.