[1] Hannover Med Sch, Dept Gastroenterol Hepatol & Endocrinol, Klin Gastroenterol Hepatol & Endokrinol, D-30625 Hannover, Germany
[2] Univ Liverpool, Dept Pharmacol, Liverpool L69 3BX, Merseyside, England
[3] Zentrum Expt & Klin Infekt Forsch GmbH, Abt Expt Virol, Twincore, Hannover, Germany
[4] Hannover Med Sch, Inst Mol Biol, D-30625 Hannover, Germany