1. LMU Munich; University Children's Hospital; Munich Germany
2. National Jewish Health; Denver CO USA
3. Children's Hospital; University of Zürich; Zürich Switzerland
4. Christine Kühne - Center for Allergy Research and Education (CK-CARE); Davos Switzerland
5. Swiss Institute of Allergy and Asthma Research (SIAF); University of Zurich; Davos Switzerland
6. Institute of Epidemiology and Medical Biometry; Ulm University; Ulm Germany
7. Comprehensive Biomaterial Bank Marburg CBBM; Fachbereich Medizin der Philipps Universität Marburg; Zentrum für Tumor und Immunbiologie ZTI; Marburg Germany
8. Member of the German Centre for Lung Research (DZL); Munich Germany
9. Department of Environmental Science; Inhalation Toxicology Laboratory; University of Eastern Finland; Kuopio Finland
10. Swiss Tropical and Public Health Institute; Basel Switzerland
11. University of Basel; Basel Switzerland
12. Children's Hospital Schwarzach; Schwarzach Austria
13. Teaching Hospital of Paracelsus Medical Private University Salzburg; Salzburg Austria
14. Department of Respiratory Disease; University Hospital; University of Besançon; Besançon France
15. Department of Health Protection; National Institute for Health and Welfare; Kuopio Finland
16. Department of Public Health; University of Helsinki; Helsinki Finland
17. Children's Hospital of Eastern Switzerland; St. Gallen Switzerland
18. Comprehensive Pneumology Centre Munich (CPC-M); German Centre for Lung Research (DZL); Munich Germany