Advances and challenges in bioprinting of biological tissues and organs.

The integration of robotic systems into bioprinters can facilitate the construction of high-resolution and complex tissue structures via digitally controlled robotic arms equipped with different types of printheads.17 Each of the printing components can be individually employed to fabricate different parts of tissue constructs, which can subsequently be assembled to create multi-functional heterogeneous structures. Three-dimensional (3D) bioprinting is an emerging additive manufacturing technique that has shown potential for fabricating complex biologically active constructs by exerting control over the positioning of cells and biomaterials using computer-aided systems. Harvesting cells from their native environments and manipulating them using bioprinters can expose cells to high levels of stress and change their gene-expression profiles.1 In addition, some cells may die or migrate out of the bioprinted constructs after implantation. Also, the inclusion of stimuli-responsive and AI components in bioinks can control the in vivo functionality of bioprinted tissues after implantation and pave the way toward constructing biomimetic and functional tissue constructs. [Extracted from the article]