1. University Children's Hospital Munich; Munich; Germany
2. Technische Universität München, Chair of Animal Hygiene; Freising; Germany
3. Department of Occupational and Environmental Health; Institute of Environmental Medicine; Karolinska Institutet; Stockholm County Council; Stockholm; Sweden
4. Department of Medicine, Clinical Immunology and Allergy Unit; Karolinska Institutet; University Hospital; Stockholm; Sweden
5. Translational Immunology Unit; Department of Medicine; Karolinska Institutet; University Hospital; Stockholm; Sweden