1. Spinal Studies, Robert Jones & Agnes Hunt Orthopedic Hospital & ISTM, Keele University, Oswestry, Shropshire, SY10 7AG, UK.
2. Arthritis Research UK Tissue Engineering Centre, UK
3. Department of Biology, University of York, York, YO10 5DD, UK
4. Musculoskeletal Research Group, Institute of Cellular Medicine, Newcastle University & Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE1 7RU, UK
5. Musculoskeletal Programme, School of Medicine & Dentistry, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, AB25 2ZD, UK