LONDON

By Health Newswire reporters

US researchers believe they have developed a new method that could one day help create functional human organs, such as kidneys and livers, for human transplantation.

Scientists from Harvard Medical School and the Massachusetts Institute of Technology (MIT) say the technique involves building a network of microscopic tubes, similar to that seen in the circulatory system, to supply oxygen and nutrients to liver or kidney cells that have been grown in the laboratory.

Using advanced computer models, these networks are designed and etched onto silicon surfaces that are then used as a mould to transfer the pattern onto a biocompatible polymer. Two of these films are then stuck together with a porous membrane sandwiched between them.

Lead researcher on the study Mohammad Kaazempur-Mofrad, from MIT’s department of mechanical engineering and division of biological engineering, said, “These technologies create a precise architectural framework for the liver or kidney cells that are responsible for the functional replacement of the vital organs.”

The researchers explained that tissue-engineering methods have been successful in creating tissues such as skin and cartilage, but have so far failed to create functional vital organs.

The scientists add that this is because although these methods provide structural support they fail to build enough vascular support, in the form of blood vessels, to maintain the cells in the organ.

Mr Kaazempur-Mofrad explained that the new process overcomes this problem. “Our microfabricated devices can efficiently supply oxygen and nutrients to sustain the viability of human liver and kidney cells for at least one week in the lab,” he said.

He added that experiments showed that 96 per cent of kidney cells survived for one week and 95 per cent of liver cells survived for two weeks.

So far, the scientists have managed to implant an experimental liver device into a rat that lasted a week. However, the device only consisted of one layer. The scientists estimate it will take around 30-50 layers to represent a fully functioning liver.

“So far we have succeeded in making individual, functioning units but the ultimate goal is to make whole, functional organs,” concluded Mr Kaazempur-Mofrad.

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