Bone tissue engineering using marrow stromal cells

Bone tissue defects cause a significant socioeconomic problem, and bone is the most frequently transplanted tissue beside blood. Autografting is considered the gold standard treatment for bone defects, but its utility is limited due to donor site morbidity. Hence, much research has focused on bone tissue engineering as a promising alternative method for repair of bone defects. Marrow stromal cells (MSCs) are considered to be potential cell sources for bone tissue engineering. In bone tissue engineering using MSCs, bone is formed through intramembranous and endochondral ossification in response to osteogenic inducers. Angiogenesis is a complex process mediated by multiple growth factors and is crucial for bone regeneration. Vascular endothelial growth factor plays important roles in bone tissue regeneration by promoting the migration and differentiation of osteoblasts, and by inducing angiogenesis. Scaffold materials used for bone tissue engineering include natural components of bone, such as calcium phosphate and collagen I, and biodegradable polymers such as poly(lactide-coglycolide). However, ideal scaffolds for bone tissue engineering have yet to be found. Bone tissue engineering has been successfully used to treat bone defects in several human clinical trials to regenerate bone defects. Through investigation of MSC biology and the development of novel scaffolds, we will be able to develop advanced bone tissue engineering techniques in the future.