1. Department of Endocrinology, Diabetology and Metabolism, University Hospital Essen, University Duisburg-Essen, Essen, Germany
2. Endocrine Laboratory, Department of Clinical Chemistry, Amsterdam Gastroenterology Endocrinology and Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
3. Institute for Medical Microbiology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
4. Institute for Experimental Immunology and Imaging, University Hospital Essen, University Duisburg-Essen, Essen, Germany