1. Department of Dermatology; University of Lübeck; Lübeck Germany
2. Euroimmun Medizinische Labordiagnostika AG; Lübeck Germany
3. Institute of Transfusion Medicine; University Hospital of Schleswig-Holstein; Lübeck and Kiel Germany
4. Institute of Transfusion Medicine and Immune Hematology; German Red Cross Blood Donor Service Baden-Württemberg - Hessen; Clinics of the Goethe University; Frankfurt Germany
5. Transfusion Medicine, Cellular Therapeutics and Hemostaseology; Clinics of the Ludwigs-Maximilians-University Munich; München Germany
6. Department of Rheumatology and Vasculitis Center; Clinical Center Bad Bramstedt; University of Lübeck; Lübeck Germany