Protein microarray allergen profiling in bronchoalveolar lavage fluid and serum of horses with asthma.
Authors: Wyler Michelle, Sage Sophie Elena, Marti Eliane, White Samuel, Gerber Vinzenz
Journal: Journal of veterinary internal medicine
Summary
# Editorial Summary Researchers in Switzerland used protein microarray technology to profile allergen-specific immunoglobulin E (IgE) in both serum and bronchoalveolar lavage fluid (BALF) from 44 horses with asthma and 39 healthy controls, aiming to establish which allergen sensitivities best characterise equine asthma and whether blood tests could reliably predict respiratory sensitisation patterns. The three allergen groups most strongly associated with asthma diagnosis were fungal proteins (particularly *Aspergillus fumigatus*), insect proteins (*Culicoides* species), and latex, with BALF analysis proving significantly more discriminatory than serum testing (area under curve 0.751 versus 0.585). Whilst nine allergens appeared in both serum and BALF models, the IgE concentrations in these compartments showed only weak to moderate correlation, meaning a horse's serum allergen-specific IgE profile does not reliably predict its respiratory sensitisation status. For practitioners, this suggests that serum-based allergy testing should be interpreted cautiously when managing suspected asthma cases, and that sampling directly from the respiratory tract provides substantially superior diagnostic information—though the practical logistics of BALF collection mean clinicians should consider this finding when counselling owners about diagnostic approaches and tempering expectations of blood-based allergen panels alone.
Read the full abstract on PubMed
Practical Takeaways
- •Bronchoalveolar lavage fluid analysis using protein microarray provides superior diagnostic utility compared to blood serum testing for identifying allergen sensitization in asthmatic horses
- •Blood serum allergen-specific IgE testing has limited clinical value for asthma diagnosis in horses and may lead to misdiagnosis if used as a standalone diagnostic tool
- •Suspected equine asthma cases warrant BALF collection and analysis rather than relying on serological testing alone for allergen-specific diagnosis
Key Findings
- •Protein microarray allergen profiling identified fungi (Aspergillus fumigatus), insects (Culicoides spp.), and latex (Hevea brasiliensis) as the primary discriminators between asthmatic and control horses
- •BALF allergen-specific IgE detection (AUC 0.751) was markedly superior to serum-based detection (AUC 0.585) for asthma diagnosis
- •Nine shared allergens between serum and BALF models showed only weak to moderate correlations, indicating poor agreement between the two sample types
- •Serological IgE concentrations should not be used as a reliable proxy for BALF allergen-specific IgE in asthmatic horses