[1] Otto von Guericke Univ, Dept Gastroenterol Hepatol & Infect Dis, Leipziger Str 44, DE-39120 Magdeburg, Germany
[2] Otto von Guericke Univ, Dept Pathol, Magdeburg, Germany
[3] John Radcliffe Hosp, Oxford Univ Hosp NHS Fdn Trust, Translat Gastroenterol Unit, Oxford, England
[4] John Radcliffe Hosp, Oxford Univ Hosp NHS Fdn Trust, NIHR Oxford Biomed Res Ctr, Oxford, England