Bone generally develops via one of two distinct mechanisms: intramembranous ossification and endochondral ossification. In the former case, mesenchymal progenitor cells directly differentiate into osteoblasts that form bone. In the latter case, the mesenchymal progenitor cells first create a matrix of cartilage that then acts as a template to enable the remodeling or development of bone tissue. This process of endochondral ossification is the predominant way that bone is generating during the healing process after bones are broken and fractures are endured. Using stem cells to facilitate this process can, therefore, be beneficial in non-healing bone fractures.
A new study published in Acta Biomaterialia has proposed that adipose tissue can be used in bone generation as a scaffold on which adipose mesenchymal stem cells can expand and allow for endochondral ossification. The researchers showed how adipose tissue could be used in this way, through what they termed Adiscaf, to successfully generate cartilage tissue and eventually bone tissue formation. The bone tissue that formed through this process contained bone marrow elements, further demonstrating the bone’s integrity and the promise of this procedure.
Compared to other strategies for building scaffolding, this strategy appeared successful because by using adipose tissue, the adipose stem cells were exposed to their native environment and therefore likely maintained functions they otherwise may not have. Not only will these findings help to solidify our understanding of how to nurture stem cells and enable them to differentiate in ways that can be therapeutically applicable, but they also specifically show how adipose tissue may be able to be used to generate a bone organ through endochondral ossification. Future research will likely help to clarify how these findings can be applied to patients to improve bone healing.