Tóm tắt

Within the biomaterials proposed for tissue regeneration, synthetic 3D hydrogels that mimic soft tissues possessrngreat potential for regenerative medicine but their poor vascularization rate is usually incompatible with long-term cell survival. Fabrication of biomaterials that promote and/or accelerate vascularization remains nowadaysrna challenge. In the present work, hydrogels with tubular geometries ranging from 28 to 680 μm in diameter, thatrncorrespond to those of human small artery/veins and arterioles and venules, were prepared. The surface of thisrntubes was coated with proteins of the extracellular matrix assuring the adhesion of endothelial cells in arnmonolayer. Interestingly, in the case of small diameter channels, polysaccharide-based hydrogels made ofrnneutral pullulan and dextran that do not allow endothelial cell adhesion, were transformed into active materialsrnguiding endothelial cell behavior solely by modification of the internal microarchitecture, without addition ofrnproteins. Under static conditions, endothelial cell adhesion, migration, proliferation and polarization on thernhydrogel was induced, without the addition of any extracellular matrix protein or adhesion peptide; thisrnproperty was found to be directly dependent on the curvature of the internal channels. In the last years, thernimpact of the geometry of biomaterials to regulate cell behavior has been highlighted paving the way to use non-flat geometries as cues to develop biomaterials to guide tissue regeneration. Here, we report a functional ma-terial based on geometrical cues to assure endothelial cell arrangement in tubular vessel-like structures andrnproviding with new pro-vascularizing properties