1. Department of Toxicology, Hannover Medical School, 30625 Hannover, Germany
2. Department of Cell Biology in the Center of Anatomy, Hannover Medical School, 30625 Hannover, Germany
3. Department of Clinical Pharmacology, Hannover Medical School, 30625 Hannover, Germany
4. Divisions of Allergic Diseases and Internal Medicine, Mayo Clinic, Rochester, Minnesota