Production of nanoscale vibration for stimulation of human mesenchymal stem cells

Mechanical stimulation is becoming a common technique for manipulating cell behaviour in bioengineering with applications in tissue engineering and possibly regenerative therapy. Living organisms show biological responses in vivo and in vitro to various types of mechanical stimulation including vibration. The development of apparatus to produce vertical motions of nanoscale amplitude is detailed and their effect on mouse endothelial (Le2) and human mesenchymal stem cells (hMSCs) is investigated. Piezo ceramic actuators and aluminium reinforcement were utilised along with laser interferometry to ensure amplitude consistency at the nanometre level across a cell culture substrate. Peak force applied to the cells was estimated to be of nN magnitude at frequencies of 500 and 1000 Hz. Morphological changes in the cytoskeleton were found for both cell types along with increased MSC proliferation after 1 week of stimulation at 500 Hz. Changes in the nuclear size of MSCs after stimulation were also found.