1. Immunobiology Section, Laboratory of Parasitic Diseases and Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
2. Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205
3. Genentech, Inc., South San Francisco, CA 94080