1. Institute of Virology, University of Zurich, Zurich, Switzerland
2. Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
3. Department of Infectious Diseases, King's College London, London, United Kingdom
4. Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
5. Institute for Experimental Hematology, Hannover Medical School, Hannover, Germany