Ricerc@Sapienza

It is well established that the cells are able to sense and respond to mechanical loading via mechanotransduction, the process whereby mechanical stimuli are detected by cells and converted in chemical signals. Mechanotransduction plays a crucial role in the physiology of many tissues including bone. The human skeleton is constantly subjected to mechanical loading, such as vibration from the local environment or movement of the interstitial fluid to create shearing force and deformation of the bone matrix. In vitro loading systems, which aim at replicating the force values found within the bone microenvironment, allow us to better understand the processes of mechanotransduction. In the present project, an in vitro device will be developed and validated to replicate cell substrate deformation. This device will be able to apply cyclic uniaxial strains to cells cultured on silicone stretch chambers. The uniaxial stretch system will consist of three culture stretch chambers, two linear stepper motors, two linear slide rails, a plexiglass base and a PC. A software will be developed in LabVIEW to precisely controll the two motors, by regulating load parameters, i.e. the amplitude, the frequency and the waveform of the strain. The planar device structure will allow the cells to be visualized during the strain application. For the validation of the device we will use a digital image correlation (DIC) technique that will allow us to verify the local deformation imposed in the culture area of the three stretch chambers. This uniaxial strain device will be a versatile platform, which will yield to study the role of mechanical strain not only in bone cells but also in a variety of cells and tissues, like skeletal muscle, neural cells, fibroblasts and endothelial cells.