3D bioprinting of human pluripotent stem cells and smart biomaterials for tissue engineering

摘要

In recent yeans, the use of a simple inkjet technology for cell printing has triggered tremendous interest in the field of 3d biofabrication or organ printing. A key challenge has been the development of printing processes which are both controllable and less harmful, in order to preserve cell and tissue viability and functions. In this presentation, I will present the development of a microvalve-based stem cell printer [as shown in Figure 1] that has been validated to print highly viable and functional human embryonic stem cells (h-ESCs) and induced pluripotent stem cells (h-iPSCs). 3D bioprinting based on both scaffold based using biomaterials and scaffold-free approaches will be discussed. In particular, novel strategies are developed to print smart biomaterials based on alginate, DNA and peptide hydrogels for 3D stem cell constructs. This work demonstrates that the valve-based printing process is gentle enough to maintain stem cell viability, accurate enough to produce spheroids of uniform size and cell-containing hydrogel structures, and that printed cells maintain their pluripotency. Our recent work on direct differentiation of printed human stem cells to liver tissues in 3D for in-vitro drug testing applications will be presented.