Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2025
Erindi/veggspjald / Talk/poster V25
Höfundar / Authors: Dorontina Mahmuti(1), Delia Bogenstätter(1), Sigurbjörg Þorsteinsdóttir(2), Eliane Marti(1), Sigríður Jónsdóttir(2,3)
Starfsvettvangur / Affiliations: 1. Division of Neurological Sciences, Department of Clinical Research and Veterinary Public Health, Vetsuisse Faculty, University of Berne, Bern, Switzerland; 2. Institute for Experimental Pathology, Biomedical Center, University of Iceland, Keldur, Reykjavik, Iceland; 3. Faculty of Medicine, University of Iceland, Reykjavik, Iceland
Kynnir / Presenter: Dorontina Mahmuti
Background: Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis in horses caused by Culicoides saliva proteins. IBH is absent in Iceland due to the lack of relevant Culicoides species but occurs with high prevalence in exported horses. A preventive vaccination with 9 major Culicoides allergens failed to reduce IBH incidence after export. Aims: To monitor immune responses to Culicoides allergens and investigate why vaccination did not prevent IBH. Methods: Allergen-specific IgG and IgE to the 9 vaccine allergens were measured by ELISA in sera of 26 vaccinated horses in Iceland and for 30 months post-export. Non-vaccinated IBH-affected and healthy horses served as controls. Results: Vaccination induced strong allergen-specific IgG responses in Iceland, which waned over time but increased after annual boosters. Horses that remained healthy after export tended to have lower IgG responses than those that developed IBH. Vaccination did not induce allergen-specific IgE in Iceland. At the end of the study, IBH horses had significantly higher IgE than healthy horses, but vaccinated IBH horses showed lower IgE to vaccine allergens compared to unvaccinated IBH-affected controls. Conclusions: Vaccination with nine Culicoides allergens elicited robust, boostable IgG and reduced allergen-specific IgE, but this modulation did not prevent IBH. Further studies are needed to define immune mechanisms required for protection.