1. Howard Hughes Medical Institute and Partners AIDS Research Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129
2. Department of Paediatrics, Nuffield Department of Medicine, John Radcliffe Hospital, Oxford OX1 3SY, UK
3. HIV Pathogenesis Program, The Doris Duke Medical Research Institute
4. Department of Zoology, University of Oxford, Oxford OX1 3PS, UK
5. Department of Cell Biology, Harvard Medical School, Boston, MA 02115
6. irsiCaixa Foundation, Retrovirology Laboratory, University Hospital “Germans Trias I Pujol,” 08916 Badalona, Spain
7. Department of Pediatrics, University of Natal, Durban 4015, South Africa