1. Institut für Diagnostikforschung GmbH an der Freien Universität Berlin, 14050 Berlin, Germany, and Charité Medical School of the Humboldt University Berlin, Campus Virchow Hospital, Department of Internal Medicine, Division of Hepatology and Gastroenterology, 13353 Berlin, Germany, and Humboldt University Berlin, Institute of Biochemistry, 10115 Berlin, Germany