Heart valve tissue matrix is embedded with a constellation of smooth muscle and fibroblast like phenotypes whose coordination is essential for proper tissue function. The smooth muscle of the aortic root wall behaves very differently than the fibroblasts within the valve leaflets, which in turn is associated with local extracellular matrix environments that vary considerably in their structural composition and biomechanical properties. We are studying how features of the extracellular matrix milieu participate in regulating local cell phenotype. We use novel 3D tissue biofabrication techniques to replicate these heterogeneous matrix configurations and test how they direct differentiation of autologously accessible stem cells (e.g. bone marrow, fat tissue) towards valve phenotypes and promote interfacial integration. We use this information to guide the synthesis of novel biologically based polymers that are compatible with these biofabrication strategies for de novo valve conduit engineering.