1. Emory Vaccine Center, Emory University School of Medicine, Atlanta, Georgia 30329.
2. Yerkes National Primate Research Center, Emory University, Atlanta, Georgia 30329.
3. Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia 30329.
4. Current address: Antibody Solutions, Inc., c/o CDC, Atlanta, Georgia 30333.
5. Current address: University of North Carolina, Chapel Hill, North Carolina 27599.
6. HIV and Retrovirology Branch, Centers for Disease Control and Prevention, Atlanta, Georgia 30333.
7. Emory University School of Medicine Electron Microscopy Core, Atlanta, Georgia 30329.
8. Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 90892.
9. Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710.
10. Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia 30329.