Osteogenic differentiation of human mesenchymal stem cells on chip: A comparison between two nutrient feeding methods

Osteogenic differentiation of human mesenchymal stem cells (hMSCs) on chip was studied by using two types of nutrient feeding methods. The first one was with a hydraulic pressure which allows controlling the flow rate with a large dynamic range. The second one was with integrated reservoirs of relative large volumes, providing a quasi stationary culture condition (regular medium change has to be done once per day). In both cases, cells survived for several weeks but showed different behaviors of cell proliferation and differentiation. In hydraulic pressure controlled chambers, cells grow fast but the formation of calcium nodes is less efficient. Under quasi stationary conditions with an optimal initial cell density between 20 and 40 k cells/cm², both morphology and Alizarin Red staining images show a better osteogenic differentiation.