Cooperation of biological and mechanical signals in cardiac progenitor cell differentiation

The notion that cells are exclusively sensing biological signals released from remote tissues, extracellular matrix and neighboring cells has been recently challenged by the evidence that the chemical, physical and mechanical features (stiffness, surface roughness, porosity, micro- and nano-architecture, etc.) of the substrate can drive stem cell differentiation, even in the absence of specifi c biological cues. ndeed, stem cells can be pre-committed towards a defi ned phenotype matching physical and mechanical signals arising from the extracellular matrix. Therefore, scaffolds used in tissue engineering cannot be a mere substrate, but must be able to release mechanical and structural signals perceived as biologically relevant by both stem and differentiated cells, thus mimicking the in vivo microenvironment.