1. Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS,1
2. Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE,2 and
3. PowderJect Vaccines, Inc., Madison, Wisconsin 537113; and
4. Wisconsin Regional Primate Research Center, University of Wisconsin—Madison, Madison, Wisconsin 537154
5. Centre for Applied Microbiology and Research, Porton Down, Salisbury SP4 0JG,5 United Kingdom;