1. ETH Zürich, Cartilage Engineering and
Regeneration Laboratory, HPL J20, Otto-Stern-Weg 7, 8093 Zürich, Switzerland
2. Schulthess Klinik, Lengghalde 2, 8008 Zürich, Switzerland
3. Department
of Musculoskeletal Medicine, Regenerative Therapy Unit, University Hospital of Lausanne, 1011 Lausanne, Switzerland