Towards a novel ultra-high viscosity alginate scaffold for cardiac tissue engineering: Poster presented at 22nd International Seaweed Symposium, ISS 2016, Copenhagen, Denmark, June 19-24, 2016

Approximately 50% off all deaths in Europe are caused by cardiovascular diseases. To relief the burden of cardiac pathologies, researchers lack cardiac models that fully reflect the heart. Thus a new cardiac muscle model is developed to satisfy worldwide demand. One of the main problems with conventional heart muscle models is that the stiffness of conventional cell culture plastic cannot recapitulate the soft and elastic environment of the physiological heart. Therefore, ultra-high viscosity (UHV) alginate, a biopolymer obtained from a special blend of algae (L. nigrescens and L. trabeculata) is used to engineer a cardiac scaffold. UHV Alginate is highly biocompatible and its stiffness can be adjusted accordingly to the needs; gelling is induced under mild conditions and a broad range of surface modifications can mimic the natural cell microenvironment, including that of the heart. Hydrogel scaffolds are engineered with the Bioscaffolder (GeSim), a 3D printer executing additive layer manufacturing. The scaffolds generated are then seeded with induced pluripotent stem cell (hiPSC) - derived cardiomyocytes (CMs) to create a model system closely resembling the physiology of the cardiac muscle. Cardiomyocyte-populated scaffolds are characterized by means of gene expression profiling by qPCR and immunocytochemistry, to combine the molecular signature with the morphology and cytoskeletal arrangements of the cells. Furthermore, contraction profiles are investigated to evaluate the functionality of the CM-populated scaffold as a whole. The Cardiopatch can be maintained in culture for long term, showing spontaneous synchronized depolarization over the whole time period, supporting the resemblance of our constructs to the physiological conditions of a living organism. In conclusion, UHV alginates superior physical chemical features make it an exceptional substrate for tissue engineering applications