Development of a Dot-Blot Assay for the Detection of Mould-Specific IgE in the Belgian Population
Data on mould sensitization in the general population are scarce and mostly on Aspergillus fumigatus, Alternaria alternata and Cladosporium herbarum.
To validate a dot-blot assay for the detection of specific IgE and evaluate the prevalence of mould sensitization in a healthy population.
The dot-blot assay was validated against the CAP test. Sensitization rate to ten common indoor and outdoor mould species in 344 serum samples was calculated. For each serum with more than one reactivity, the “major sensitization” defined as the strongest response against a single mould species was calculated.
Intra- and inter-assay variations were both below 20%, and the positivity threshold of the test was of 0.418 kU/L for A. fumigatus. Correlation with CAP results was strong. The overall prevalence of sensitization was 32.8%, and the commonest sensitizations were against A. alternaria, A. flavus and A. niger (around 15%). The most frequent “major reactivities” were against A. niger and A. alternata (20–30%). In 25.1% of the samples, “major reactivities” were directed against a group of moulds commonly found indoor (Penicillium spp., Aspergillus versicolor, Cladosporium sphaerospermum and Cladosporium cladosporioides).
The dot-blot assay was validated for the detection of mould-specific IgE. In the general population, sensitization to indoor species was common and accounted for 25% of overall mould sensitizations.
KeywordsIgE detection Dot-blot Mould sensitization Indoor mould species
skin prick test
We are grateful to Prof. Denis Piérard (UZ Brussel VUB) for giving us access to the serum bank from normal subjects which was used in this study and to Prof. Joël de Coninck (Laboratoire de Physique des Surfaces et des Interfaces (LPSI), Université de Mons) for his help on statistics. We thank Sofie De Prins for her excellent technical assistance. This study was supported by the Belgian Scientific Policy (BELSPO) through an Ylieff fellowship.
M.V, O.D and O.M designed the study protocol. M.V analysed and interpreted data and wrote the article. O.D reviewed data analysis and interpretation and revised the manuscript. O.M recruited the patients and provided critical review of the manuscript. F.C provided CAP results for allergic patients and made manuscript revision. M.R and K.H provided critical input in the manuscript framework and reviewed the paper. All authors approved the final version of the document.
Compliance with Ethical Standards
Conflict of interest
The authors declare that they have no competing interests.
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