We bumped into a rather interesting video explaining and actually showing the process of using a 3D printer to deposit live cells! The video explains the main issue with tissue deposition: lack of a scaffold causes the deposited cells to lack structural integrity; they flop all over.
The 3D printer enables them to create a hydrogel substrate on each deposition layer. In other words, the cells are jetted out with hydrogel so that they stay put.
The video shows the printer at work, so this is not merely a proposal. What made this video even more special for us was the fun musical soundtrack!
Via YouTube