1. Department of Medicine, National Jewish Health, Denver, CO, USA
2. Center for Interstitial and Rare Lung Diseases, Pneumology, Thoraxklinik University of Heidelberg
3. German Center for Lung Research, Heidelberg, Germany
4. Department of Medicine, Weill Cornell, New York, NY, USA
5. Department of Rheumatology, Oslo University Hospital, Oslo, Norway
6. Department of Medicine, Brigham and Women’s Hospital, Boston, MA, USA