Figure 6.

Manufacturing process of prevascularized constructs. In the first step a base layer was printed (A1) followed by the deposition of the coaxial printed hollow strand in a meander-linked manner over all base layer of a printing sequence (A2). In the last step, the space between the hollow channels was filled with another cell-laden gel (A3). A printing sequence created samples with one continuous hollow strand (B). The hollow strands that are not embedded in the hydrogel substrate were mechanically separated. The corresponding prevascularized constructs had different distances between their channels ranging from 1 mm (C1), 1.5 (C2) to 2 mm (C3). The left constructs still contain the core-located gelatin while the material is aspirated in the right constructs (Scale Bar: 4.5 mm). (D): Time dependent cell viability of prevascularized HepG2-laden constructs. The cell viability at every time point is normalized to the viability of a non-prevascularized construct serving as the control. Graphs marked with * show a statistical significance compared to avascular sample (significance level: * p > 0.005, n = 8).