A group of scientists, led by Jin Nam at the University of California-Riverside, have found a new way to optimize the use of stem cells for orthopedic purposes. The technique involves strategically using biomechanical forces to create the specific cell type needed to repair orthopedic tissues.
The normal development of bone and cartilage critically depend on mechanical stimulation, yet the ideal level of mechanical stimulation differs for cells that make up bone and cells that make up cartilage. The researchers therefore reasoned that employing the right level of mechanical stimulation could help stem cells differentiate into the cell type needed for specific individual injuries.
A certain type of stem cell, called the mesenchymal stem cell (MSC) has been shown to be capable of regenerating musculoskeletal tissues. In addition, when MSCs obtained from the patient are used to regenerate that patient’s musculoskeletal tissues, tissue rejection tends to be prevented because the immune system recognizes the transplanted cells as the body’s own cells. Nonetheless, stimulating the stem cells to form tissue has relied mainly on biochemical and biophysical phenomena, which can present a variety of challenges. To avoid those challenges, scientists hoped that they could use biomechanical stimulation for the same purpose.
In their experiment, Nam and his colleagues showed that different levels of biomechanical force could indeed lead MSCs to differentiate into osteoblasts and chondrocytes, the cells that make up bone and cartilage, respectively. These promising results suggest that combining these types of stem cells with targeted biomechanical stimuli will enable better repair of a variety of types of orthopedic damage.
Going forward, researchers hope to better understand the details of how biomechanical cues can determine the fate of stem cells and to use this information to induce stem cells to differentiate into the desired cell type, according to the particular injury. This experiment conducted at the University of California-Riverside helps shed more light on the continued value of stem cells in medicine, as well as the potential benefits of combining these cells with approaches that can help personalize the treatments offered.
Horner, C.B. et al. (2016). Magnitude-dependent and inversely-related osteogenic/chondrogenic differentiation of human mesenchymal stem cells under dynamic compressive strain. Journal of Tissue Engineering & Regenerative Medicine. doi: 10.1002/term.2332