1. Progenics Pharmaceuticals, Inc., Tarrytown, New York 10591
2. Center for Biomedical Research, Population Council, New York, New York 10021
3. Jefferiss Research Trust Laboratories, Wright-Fleming Institute, Imperial College, London W2 1PG, United Kingdom
4. Department of Microbiology and Immunology
5. Department of Pediatrics, Weill Medical College of Cornell University