CLAIRE O'CONNELL
JAPAN:It's either bonkers or brilliant - only time will tell. A Japanese researcher is developing a printer to literally print out three-dimensional human organs, such as hearts, for transplant.

Wanting to address the dearth of donor organs, paediatrician Makoto Nakamura left the clinic and spent over a decade researching options for making transplant organs available.

He turned to the concept of "bioprinting", which uses a printer device to disperse cells (instead of ink droplets) onto a biomaterial.

The idea is to build up organs sequentially, layer by layer, that will then function in the human body. In theory, using cells derived from the patient to print out their new organ could help overcome problems of rejection, which is currently an issue for transplant recipients.

Nakamura's ultimate goal is to generate healthy hearts for transplant, although he admits that is still 20 years into the future. So far he has shown that cells survive the printing process and he has successfully produced a multi-layered tube of living cells.

Scientists in the US are also advancing the field, working out how to print cells in a manner that allows biological structures to self-assemble.

"I'm not envisioning making superhuman cyborgs," said Nakamura, who is based at the University of Toyama in central Japan.

"There are simply lives that could be saved if there are organs," he says.