Feasibility of Cell Lines for In Vitro Co-Cultures Models for Bone Metabolism

Today, over 70 diseases and health conditions are known that negatively affect the bone quality directly or indirectly by their medical treatment, establishing the term metabolic bone disease. Already every third hospitalized patient in Europe suffers from musculoskeletal injuries or diseases. Facing an ageing society and a more and more sedentary lifestyle the number of chronic diseases and consequently metabolic bone diseases are expected to continuously increase. In order to investigate the various disease constellations and/or develop new treatment strategies suitable models representing bone metabolism are required. Many in vivo , ex vivo and in vitro models have been described, which have their advantages and limits. We here summarize the advantages and challenges of frequently used models to investigate bone metabolism, focusing on in vitro co-cultures of bone forming osteoblasts and osteoclasts. Comparing own data with published models, we further elaborate the feasibility of commonly used cells lines for such in vitro co-culture models, in order to provide an easy, constantly available, and up-scalable model system for screening alterations in bone metabolism.