Evaluation of a diagnostic ELISA for insect bite hypersensitivity in horses using recombinant Obsoletus complex allergens

• Published in: The veterinary journal (1997) Vol. 200; no. 1; pp. 31 - 37
• Main Authors: van der Meide, Nathalie M.A., Savelkoul, Huub F.J., Meulenbroeks, Chantal, Ducro, Bart J., Tijhaar, Edwin
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-04-2014
• Subjects: Allergens - immunology; Animals; antibodies; Ceratopogonidae; Culicoides; culicoides-obsoletus; Diagnostic IgE ELISA; Enzyme-Linked Immunosorbent Assay - veterinary; equine ige; expression; extract; genome-wide association; Horse; Horse Diseases - diagnosis; Horse Diseases - immunology; Horses; Hypersensitivity - diagnosis; Hypersensitivity - immunology; Hypersensitivity - veterinary; Immunoglobulin E; Insect bite hypersensitivity; Insect Bites and Stings - immunology; Insect Bites and Stings - veterinary; Netherlands; Obsoletus complex; plasma-cells; Recombinant allergens; responses; Sensitivity and Specificity; skin; Netherlands; Insect bite hypersensitivity; Recombinant allergens; Culicoides; Obsoletus complex; Diagnostic IgE ELISA; Horse
• ISSN: 1090-0233; 1532-2971
• DOI: 10.1016/j.tvjl.2013.12.004

Culicoides spp. of the Obsoletus complex belong to the most important species of midge, involved in causing insect bite hypersensitivity (IBH) in horses in The Netherlands. The aim of the current study was to evaluate seven different Obsoletus complex-derived recombinant allergens (Cul o 1–Cul o 7) and to compare these with Obsoletus complex whole body extract (WBE) in an IgE ELISA, using sera of 194 clinically-confirmed cases of IBH and 175 unaffected horses. The highest test accuracy was obtained with WBE, followed by Cul o 2, 3 and 5.
Two ELISAs with a combination of recombinant allergens, Combi-1 (Cul o 3, 5 and 7) and Combi-2 (Cul o 1, 2, 5 and 7) were additionally performed and both resulted in high test accuracies close to that obtained with WBE. Combi-1 resulted in the best sensitivity and specificity, both 89%. Both Combi-1 and Combi-2 performed less well with samples collected in winter, but over 70% of the IBH-affected horses could still be identified. In conclusion, a combination of three Obsoletus complex recombinant allergens (Cul o 3, 5 and 7) could potentially replace Obsoletus complex WBE in an IgE ELISA for diagnosis of IBH in horses.