1 Microbiology and Immunology, 600 16th Street, Room S572E, Box 2280, San Francisco, CA 94143-2280, USA. Electronic address: raul.andino@ucsf.edu.
2 The Herbert S. Gasser Professor, Departments of Medicine, Molecular Microbiology, Pathology & Immunology, The Andrew M. and Jane M. Bursky Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, USA. Electronic address: diamond@wusm.wustl.edu.