Equine asthma constitute a major problem in the equine industry and for horse welfare. Similar to human asthma , different disease phenotypes are recognized in equine asthma based on clinical symptomas and age of presentation, some of which are associated with specific inflammatory cell types that reside in the lungs. In this FORMAS funded project we apply single-cell transcriptomics to analyze cells sampled from the alveolar space and airway wall of horses suffering form equine asthma and healthy controls. A comprehensive atlas of the landscape of cells in the airway of horses in equine asthma will lead to improved understanding of the inflammatory processes implicated in the disease and clarify differences between equine asthma phenotypes