1. Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
2. Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA.
3. Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany.
4. German Center for Infection Research, partner site Bonn–Cologne, 50931 Cologne, Germany.
5. Department I of Internal Medicine, Faculty of Medicine and University Hospital of Cologne, University of Cologne, 50931 Cologne, Germany.
6. Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02129, USA.
7. Division of Gastroenterology, Massachusetts General Hospital, Boston, MA 02114, USA.
8. Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
9. Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
10. Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany.