Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023
Höfundar / Authors: Sigríður Jónsdóttir1, Sara Björk Stefánsdóttir1, Jasmin Birras2, Anja Ziegler2, Anneli Graner3, Ralf Mueller3, Vilhjálmur Svansson1, Sigurbjörg Þorsteinsdóttir1, Eliane Marti2
Starfsvettvangur / Affiliations: 1. Institute for Experimental Pathology, Biomedical Center, University of Iceland, Keldur, Reykjavik, Iceland. 2. Vetsuisse Faculty, University of Bern, Switzerland. 3. Center of Clinical Veterinary Medicine, LMU Munich, Munich, Germany.
Kynnir / Presenter: Sigríður Jónsdóttir
Background: Insect bite hypersensitivity (IBH) is an IgE-mediated dermatitis of horses caused by bites of Culicoides spp. IBH does not occur in Iceland due to absence of the causative insects but has a high incidence in horses exported to Culicoides areas. We developed a vaccine consisting of 9 IBH allergens in adjuvants. Our aim is to investigate if the vaccine can lower the incidence of IBH in exported horses and reduce clinical signs of horses with IBH.
Methods: 27 horses were included in the prophylactic part; vaccinated 3 times before export, received one booster every spring and followed for 3 summers. In the therapeutic part; 10 received the vaccine and 8 the placebo. Clinical signs were monitored pre-treatment and 2 summers during treatment.
Results: Of the 27 horses 16 developed IBH after the 3 summers with Culicoides exposure. In a basophil activation test, the vaccinated horses that developed IBH showed significantly lower response to the vaccine allergens compared to unvaccinated IBH horses.
The treated IBH horses showed a significantly stronger reduction of clinical signs compared to placebo after the first year and this difference was more pronounced during the second treatment year.
Conclusions: Our vaccine did not reduce the incidence of IBH in exported horses although it reduced the degree of sensitization to the allergens. Using our vaccine as a treatment for IBH significantly reduced clinical signs but larger studies of longer duration is needed.