1. Gene Therapy Program, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104.
2. Department of Gene Therapy, Imperial College London, London, SW3 6LR, United Kingdom.
3. UK Cystic Fibrosis Gene Therapy Consortium.
4. Hospital of the University of Pennsylvania, Philadelphia, PA 19104.
5. Medical Genetics Section, University of Edinburgh, Edinburgh, EH4 2XU, United Kingdom.
6. Gene Medicine Research Group, University of Oxford, Oxford, OX3 9DU, United Kingdom.