AC2T research GmbH 1 article published in JoVE Medicine Biotribological Testing and Analysis of Articular Cartilage Sliding against Metal for Implants Christoph Stotter1,2, Christoph Bauer1, Bojana Simlinger3, Manel Rodriguez Ripoll3, Friedrich Franek3, Thomas Klestil1,2, Stefan Nehrer1 1Faculty of Health and Medicine, Department for Health Sciences, Medicine and Research, Center for Regenerative Medicine, Danube University Krems, 2Department of Orthopedics and Traumatology, LK Baden-Mödling-Hainburg, 3AC2T research GmbH This protocol describes the preparation, biotribological testing, and analysis of osteochondral cylinders sliding against metal implant material. Outcome measures included in this protocol are metabolic activity, gene expression and histology.