Evaluation of Precise Optimal Cyclic Strain for Tenogenic Differentiation of MSCs

Although there are a number of papers relating to tenogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) using uniaxial cyclic stretching stimulation with homogeneous strain field, it has been pretty hard to figure out the optimal normal strain in the stretch direction for the differentiation. In the present study, our group has developed a non-uniform strain field system to elucidate the optimal normal strain in one-time experiment in principle. A relationship between the normal strain of membrane and expression levels of the differentiation marker proteins, type I collagen (Col I) and tenascin-C (Tnc), derived from stretched cells was obtained. Finally, the rigorous optimal normal strains were clarified 7.9 and 8.5 % for Col I and Tnc, respectively. Additionally, we found that a dependence of protein expression levels with the normal strain of membrane was different in each protein, which would be crucial in the field of embryology and regenerative medicine.