Gelatin-Based Hydrogels for Controlled Cell Assembly

Controlled cell assembly technique is a new research area in complex organ development technologies. Gelatin-based hydrogels, such as gelatin, gelatin/alginate, gelatin/chitosan, gelatin/fibrinogen, gelatin/hyaluronan, and gelatin/alginate/fibrinogen, have played an important role in the rapid fabrication of tissue or organs with well-defined structures and functions. Cryoprotectants, such as dimethylsulfoxide (DMSO) and glycerol, can be easily incorporated into the system for long-term conservation of the cell containing constructs. Hepatocytes, chondrocytes, cardiac myocytes, and adipose-derived stromal cells (ADSCs) are used to show function of the assembled cells. ADSCs can be controlled to differentiate into different targeted cell types according to their positions within the orderly predesigned three-dimensional (3D) constructs. A multicellular model for the metabolic syndrome was established along with the development of the double-syringe deposition system which lead to a hybrid cell/hydrogels construct with a vascular-like network fabricated using a digital model. The preliminary results indicate that the double-syringe assembly technique is a powerful tool for fabricating complex constructs with special intrinsic/extrinsic structures, and has the potential to be widely used in regenerative medicine and drug screening.