'Organ Printing' Could Drastically Change Medicine

The process can be repeated over and over, adding liquid, gelling it, printing more cells, and building layer upon layer, creating three dimensions.

Limitations and Obstacles

Right now, scientists are limited to a maximum of about 2 inches of thickness. Crossing that threshold presents one of the technique's first big hurdles.

"When you print something very thick, the cells on the inside will die -- there's no nutrients getting in there -- so we need to print channels there and hope that they become blood vessels," Boland said.

In any given human organ, there are blood vessels feeding the organ to keep it alive and working properly. Without the blood vessels, the organ will die and that's the problem facing researchers in building an organ for use in a human: How do you get the printed organ to grow and maintain blood vessels?

Although there are a few competing schools of thought on this, like most things in science, work, ingenuity, and maybe a little money are what researchers say will put printed organs in live humans.

"In the future -- maybe 50 years from now -- we will be able to make very complex organs and bones, and very complex tissues," he said.

And when they can, they won't have to worry about rejection because the replacement part will be catered to the individual receiving it.

"With the printers, we have the ability to tailor the material very well depending on how much crosslinker and so on," Boland said. "So we can actually match the properties of the heart cell [for example] with the properties of the tissue."

Rapid Prototyping

The concept behind organ printing is one that's been used in the manufacturing world for years, "rapid prototyping."

"Rapid prototyping is nothing more than layer-by-layer deposition of any materials," explained Mironov. "What is new is that instead of ceramic, instead of polymer, instead of some other nonorganic stuff, we use living tissue and living cells."