Thrombopoietic Agents: Novel Osteoinductive Agents for Bone Healing

Achieving bone union remains a significant clinical dilemma. The use of osteoinductive agents, specifically BMPs , has gained wide appreciable attention. However, multiple side effects, including increased incidence of cancer, has renewed interest in investigating other alternatives that provide safer, yet effective bone regeneration. Here we demonstrate the robust bone healing capabilities of the main megakaryocyte growth factor, thrombopoietin (TPO) and/or second generation TPO agents in mice, rats, and pigs. This bone healing activity is shown in two fracture models (critical sized defect or CSD and closed fracture) and with local or systemic administration. Our transcriptomic analyses, cellular studies, and protein arrays demonstrate that TPO enhances angiogenesis, an important aspect of successful bone repair. Finally, the therapeutic potential of thrombopoietic agents is high since they are used in the clinic for other indications (e.g. thrombocytopenia). n=12, 3 treatments (Saline, BMP-2 and TPO) and 4 replicates of each treatment