1. Center for Allergy Research, Division of Respiratory Medicine and Allergy, Department of Medicine; Karolinska Institutet; Stockholm Sweden
2. Department of Internal Medicine, Asthma and Allergy; Medical University of Lodz; Lodz Poland
3. Department of Pulmonology; Medical Centre Leeuwarden; Leeuwarden The Netherlands
4. Department of Respiratory Medicine, Academic Medical Centre; University of Amsterdam; Amsterdam The Netherlands
5. Section of Respiratory Diseases, Department of Medical Sciences; University of Ferrara; Ferrara Italy
6. Department of Respiratory Diseases; University of Marseille; Marseille France
7. Department of Medicine; Jagiellonian University; Krakow Poland
8. Institute of Biomedicine and Molecular Immunology; Italian National Research Council; Palermo Italy
9. 7th Respiratory Department and Asthma Centre; University of Athens; Athens Greece
10. Department of Respiratory Medicine; Ghent University Hospital; Ghent Belgium