A Better Understanding of Molecular Mechanisms Leading to Asthma and Its Remission

to determine the underlying mechanisms and molecular events involved in the inception and remission of asthma.

Methods: We will include a 40 subjects divided over the following 4 groups: i) clinical asthma remission (10 subjects), ii) complete asthma remission (10 subjects), iii) ongoing asthma (10 patients), iv) non-asthmatic healthy controls (10 subjects) in a cross-sectional study. All subjects will be extensively clinically characterized including respiratory symptoms/questionnaires, in- and expiratory CT-scans, and parameters of large and small airway function and inflammation. In addition, blood and nasal epithelial brushes will be obtained to study the genetic and epigenetic mechanisms of asthma remission. Finally, bronchoscopy with bronchial biopsies and brushes will be performed under conscious sedation. Bronchial biopsies from all four patient groups will be used for index FACS sorting of the three most important cell types orchestrating the asthmatic inflammatory process: i.e. B lymphocytes, CD4+ T cells and CD8+ T cells. We will perform single cell whole-genome transcriptome sequencing on at least 100 cells of each type and the primary outcome of the study is to identify how the transcriptomic profile of bronchial epithelial cells is changed between asthma patients and healthy controls as a consequence of asthma inception and what transcriptomic profile changes occur in CD4+ CD8+ and B lymphocytes in the airways from subjects with asthma remission compared to patients with ongoing asthma and healthy controls.