1. Broad Institute of MIT and Harvard, 75 Ames Street, Cambridge, Massachusetts 02142, United States
2. Center for Systems Biology, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, United States
3. Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114, United States
4. Department of Immunology and Infectious Disease, Harvard School of Public Health, Boston, Massachusetts, United States
5. Howard Hughes Medical Institute, Chevy Chase, Maryland, United States
6. Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States