1. From the Laboratory of Viral Pathogenesis, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA; the Infectious Disease Unit, AIDS Research Center, Massachusetts General Hospital, Boston, MA; the Division of Hematology-Oncology, University of Pennsylvania, Philadelphia, PA; the Department of Immunology, Berlex Biosciences, Richmond, CA; and the Division of Dermatology, Brigham and Women's Hospital, Boston, MA.