''The idea is for the printer to jet out thousands of cells per second -- rather than ink droplets -- and to build them up into a three-dimensional organ.

"It would be like building a huge skyscraper on a micro level using different kinds of cells and other materials instead of steel beams, concrete and glass," he said in Toyama, Japan.
...
Nakamura has succeeded in building a tube with living cells. It measures one millimeter (0.04 inches) in diameter and has double walls with two different kinds of cells, similar to the three-layer structure in human blood vessels.

He has also made a smaller single-wall hydrogel tube that measures one-tenth of a millimeter -- as narrow as human hair.

The tubes are made by a 3-D inkjet bioprinter that Nakamura's team developed in a three-year project completed earlier this year at Kanagawa Academy of Science and Technology, a foundation based southwest of Tokyo.''

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