Joint inflammation (osteoarthritis) is a common cause of lameness in horses. There is a need for safe and effective treatments of the disease. Blood derived autologous biological products such as autologous conditioned serum (ACS) and platelet-rich plasma (PRP) are used as intra-articular treatments in horses as well as humans. The exact composition of these products is not known and the disease modifying mechanisms are not fully understood although they sometimes appear to yield good clinical results. One aim is to gain knowledge about the biological products with emphasise on their content of potential anti-inflammatory and regenerative factors. This project will also investigate the effects of the products in a well-established in vitro model of inflamed equine cartilage where anti-inflammatory and regenerative features can be identified. The project will increase the scientific knowledge about potential disease modifying properties of the biological products.