Biocad drawing software

Support media were vortexed vigorously, briefly centrifuged to remove air bubbles and transferred into a transparent, open sterile plastic box. Printing was performed within one hour from vortexing, unless indicated otherwise. Constructs were printed using 3DDiscovery® printer (regenHU, Villaz-Saint-Pierre, Switzerland) by extrusion (through 30G needles, unless stated otherwise) according to designs generated by BioCAD™ drawing software (regenHU) or according to data from STL files (sliced and processed by BioCAM™ software (regenHU)) which were downloaded from Thingiverse (www.thingiverse.com “Anatomical Human Heart” by 517860 (modified), under the Creative Commons - Attribution - Share Alike license - CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0/). Printouts were visualized by an inverted fluorescence microscope (Nikon Eclipse TI) or an upright confocal microscope (Nikon ECLIPSE NI-E). The printing process was captured from a side-view using a long working distance Dino-Light digital microscopes (AnMo Electronics, Taiwan). For extraction of the printed structures from the support medium, the box was incubated at 37°C for 30 min to cure the bioink. Then, the support medium was supplemented with alginate lyase (Sigma-Aldrich, 1U/ml) and incubated at 37°C. The digested support medium was gradually aspirated and replaced with growth medium.