1. Postgraduate School of Respiratory Medicine. Department of Experimental Medicine, University of Rome “Tor Vergata”, Rome, Italy
2. Allergy Unit, Ospedali Riuniti Marche Nord, Fano, Italy
3. Department of Clinical and Molecular Sciences, Marche Polytechnic University, Ancona, Italy
4. Allergy Unit, Department of Internal Medicine, University Hospital Ospedali Riuniti, Ancona, Italy
5. Division of Pulmonology, S. Corona Hospital, Pietra Ligure, Italy
6. Department of Medicine and Surgery, Respiratory Disease and Lung Function Unit, University of Parma, Parma, Italy
7. Department of Experimental Medicine, Unit of Respiratory Medicine, University of Rome “Tor Vergata”, Rome, Italy