14 março | 14h00 |
Grande Auditório FCT NOVA
Ischemic heart disease kills millions of people across the world every year and has contributed to about 13% of total global deaths in 2012. The vast majority of these heart diseases are slow, degenerative conditions that eventually lead to heart failure over a period of months to years. Thus, there is time and opportunity to intervene in the disease process and repair the damage. The heart, however, does not have the ability to regenerate or undergo repair that is sufficient to overcome myocardial infarction (MI) or other types of cardiomyopathy. The development of functionally relevant in vitro human organ models could have the potential to address these issues. There is therefore a need for a tissue fabrication process that is capable of scaling with the number of materials, size, and geometric complexity of the engineered tissue. We present a method to 3D-bioprint collagen using freeform reversible embedding of suspended hydrogels (FRESH) to engineer components of the human heart at various scales, from capillaries to the full organ. Control of pH-driven gelation provides 20-micrometer filament resolution, a porous microstructure that enables rapid cellular infiltration and microvascularization, and mechanical strength for fabrication and perfusion of multiscale vasculature and tri-leaflet valves. We found that FRESH 3D- bioprinted hearts accurately reproduce patient-specific anatomical structure as determined by micro–computed tomography. Cardiac ventricles printed with human cardiomyocytes showed synchronized contractions, directional action potentialpropagation, and wall thickening up to 14% during peak systole.