Ricerc@Sapienza

Mechanical cues of the cell surrounding affect cells' behaviour via mechanotransduction. Indeed, cells are able to perceive and respond to external mechanical forces from growing microenvironment, as well as to the stiffness of the underlying extracellular matrix. However, the interrelated effects of mechanical stimuli on cellular response are poorly understood yet. In this project, I will propose a novel experimental approach to couple the substrate stiffness with an external applied stretch to elucidate and compare the physiologic and altered cellular mechano-signalling. On this basis, I will optimize an innovative cell culture system, developed in our laboratory, to provide uniaxial longitudinal stretch by a linear actuator on the silicone chamber surface where cells will be seeded. An additive linear motor will be devised to automatically compensate the longitudinal displacement imposed by the main actuator, thus allowing a continuous cells' observation during the stretch. Moreover, optical software will be employed to elaborate post-processed cellular images for biological analysis. In this view, I will first develop a real-time program in LabVIEW for the cellular imaging acquisition and for the actuators' synchronization. In parallel, I will design and realize the silicone stretch chamber for cell culture through a 3D printed mold. Subsequently, I will incorporate to the silicone chamber an ad-hoc customized substrates, realized to simulate the native matrices stiffness. A strict characterization of each custom-made substrate in terms of the matrix stiffness and strain field distribution on the bottom area will be performed before cell testing. Finally, a series of tests will be carried on studying the cellular response to different substrates rigidities in static/dynamic stretch, testing healthy cells, like osteoblasts and muscle cells, and pathologic ones, such as osteosarcoma and transfected SOD cells, respectively.