FACTORINK · Functional bioinks for engineered tissues

Bioinks are materials that hold cells during bioprinting. They perform key functions, including protecting cells from high shear stress during the printing process but also, and importantly, provide the extracellular environment for cells after printing. Bioinks must be made of biocompatible materials that in addition should provide the functional environment needed for cells to perform their functions. This is critical as bioprinting underpins developments of in vitro tissue models to advance biomedical research and drug testing. The functionality of bioinks must recapitulate aspects of the extracellular matrix (ECM) and should include mechanical and biochemical considerations. For example, bioinks should result in constructs of well-defined rigidity as this influences processes such as stem cell differentiation or cancer progression. Also, bioinks must provide cells with controlled density of adhesion proteins and growth factors – this is key to induce relevant signalling pathways. Yet bioinks that are currently in the market are limited to basic adhesion peptides and lack the ability to retain growth factors that instead quickly diffuse out of the system after printing. We have recently developed a new class of bioinks that incorporate ECM proteins (like fibronectin and laminin) that are incorporated into a hydrogel matrix without crosslinking, enabling an easy and robust printing process. We want to unleash the potential of the bioinks by demonstrating their ability to hold multiphasic models containing stem cells, endothelial cells and the immune system. The data gathered through this application should help define the commercial route of the products and would lead to creating new intellectual properties.