1. Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, Gothenburg University, 40530 Gothenburg, Sweden
2. Department of Human Structure and Repair, Anatomy and Embryology Unit, Ghent University, 9000 Ghent, Belgium
3. Department of Respiratory Medicine, Sahlgrenska University Hospital, 41345 Gothenburg, Sweden
4. Division of Medical Oncology, University of Colorado School of Medicine, Aurora, CO 80045