CANCELLED. WILL BE RESCHEDULED IN THE NEW YEAR. Skeletal stem cells in synovial joints play important roles in joint maintenance and repair throughout life. Work in our lab has focused on understanding the ontogeny, identity and functions of stem and progenitor cells in the adult synovial joint. Progeny of Gdf5-expressing joint interzone cells that form the joint tissues during development continue to function as stem cells in adult joints and play important roles in the maintenance and repair of joint tissues during adult life. Our recent work has focussed on understanding the roles of Gdf5-lineage cells in the formation of osteophytes in osteoarthritis and joint destruction in inflammatory arthritis.