1. F. Altare, A. Durandy, S. Lamhamedi, F. Le Deist, E. Jouanguy, R. Döffinger, INSERM U429, Hôpital Necker-Enfants Malades, Paris 75015, France.
2. D. Lammas, P. Drysdale, D. Kumararatne, Department of Immunology, University of Birmingham Medical School, Birmingham B15 2TT, UK.
3. J.-F. Emile, Service d'Anatomo-Pathologie, Hôpital Paul Brousse, Villejuif 94804, France.
4. F. Bernaudin, Service de Pédiatrie, Centre Hospitalier Intercommunal, Créteil 94010, France.
5. O. Jeppsson, Department of Pediatrics, University Hospital, Norsborg 145 01, Sweden.