1Laboratoire de Génétique des Virus Oncogènes - CNRS UA 1301, Institut Gustave Roussy, Pavillon de Recherche 2, Niveau 3C2, 39 rue Camille Desmoulins, 94805 Villejuif, France
2Departments of Pathology and Microbiology and Anatomy, School of Medical Sciences, University of Bristol, University Walk, Bristol BS8 1TD, U.K.