Biofabrication of Cell-Loaded 3D Spider Silk Constructs

Biofabrication is an emerging and rapidly expanding field of research in which additive manufacturing techniques in combination with cell printing are exploited to generate hierarchical tissue‐like structures. Materials that combine printability with cytocompatibility, so called bioinks, are currently the biggest bottleneck. Since recombinant spider silk proteins are non‐immunogenic, cytocompatible, and exhibit physical crosslinking, their potential as a new bioink system was evaluated. Cell‐loaded spider silk constructs can be printed by robotic dispensing without the need for crosslinking additives or thickeners for mechanical stabilization. Cells are able to adhere and proliferate with good viability over at least one week in such spider silk scaffolds. Introduction of a cell‐binding motif to the spider silk protein further enables fine‐tuned control over cell–material interactions. Spider silk hydrogels are thus a highly attractive novel bioink for biofabrication. Printed silk: A novel bioink system based on recombinant spider silk proteins was developed. 3D cell‐loaded spider silk hydrogel constructs prepared by using robotic dispensing supported viability of the embedded cells for at least a week. Cytocompatibility, physical cross‐linking without the need for additives, and the possibility to tailor cell–material interactions through the introduction of cell‐adhesion motifs render this a versatile system for biofabrication.