1. School of Biological Sciences, University of Manchester, Manchester M13 9PT, UK
2. Division of Medical Sciences, University of Birmingham, Birmingham B15 2TH, UK
3. Department of Experimental Pathology, Lund University, S-221 85 Lund, Sweden
4. Clinical and Diagnostic Oral Sciences, Barts and The London, Queen Mary's School of Medicine and Dentistry, London E1 2AT, UK
5. Department of Molecular Medicine, Max Plank Institute for Biochemistry, D-82152 Martinsried, Germany