Development of an effective three dimensional fabrication technique using inkjet technology for tissue model samples

Engineering of a functional tissue model is considered integral to the development of alternative methods to animal testing. Tissues and organs have three dimensional (3-D) structures and are composed of variety of components, multiple types of cells and extracellular matrices proteins. For engineering those structures in vitro, effective 3-D fabrication technique is required. We have attempted to fabricate 3-D structures using inkjet printing technology to arrange cells and various biomaterials freely in 3-D space. In order to fabricate 3-D structures, hydrogel was used, and we have developed an original inkjet system specialized for fabrication of 3-D hydrogel structures. In this study, we performed spatially controlled hydrogel structures including cells in 3-dimensions using our original inkjet system. Cells were suspended in gel precursor solution, and hydrogels including the cells were formed by printing into reactant solution for sol-gel reaction. Using our inkjet system, we successfully fabricated several 3-D hydrogel structures such as sheet and tube with cells. We demonstrated an inkjet-based 3-D fabrication technique using hydrogel/cells. Those results suggested that 3-D tissue model samples can be designed and fabricated by using inkjet-based 3-D fabrication technique. Such 3-D bio-manufacturing technology will contribute to the development of alternative methods to animal experiments.