Mechanical stimulation of in vitro tissue growth using magnetic beads Cells and tissues are sensitive to mechanical forces applied to them. In particular bone forming cells and connective tissues composed of cells embedded in fibrous extracellular matrix (ECM) are continuously remodeled in response to the loads they bear. The mechanoresponses of cells embedded in tissue include proliferation differentiation apoptosis internal signaling between cells and formation and resorption of tissue. Experimental in vitro systems of various designs have demonstrated that forces affect tissue growth maturation and mineralization. However the results depended on different parameters such as the type and magnitude of the force applied in each study. Some experiments demonstrated that applied forces increase cell proliferation and inhibit cell maturation rate while other studies found the opposite effect. When the effect of different magnitudes of forces was compared some studies showed that higher forces resulted in a cell proliferation increase or differentiation decrease while other studies observed the ...