`Organs' being developed to aid transplant patients

Researchers in Scotland are developing "artificial organs" that could help keep transplant patients alive while awaiting a donor. The devices use living cells that perform some functions of the liver and the pancreas.

The Festival of Science in Glasgow heard a number of papers about artificial skin, tissue engineering and cell cultures in the session "From Genes and Cells to Healthcare". It provided a glimpse into the future of medicine and how doctors might overcome a shortage of donor organs.

"There is no treatment for acute liver failure except transplantation, but it is reversible," said Dr Helen Grant, of the University of Strathclyde. The liver could sometimes recover if it could be temporarily taken out of service, and an artificial liver, under development at Strathclyde, would provide this respite. "That short- term support is what is offered by artificial organs," she said.

The team has developed a method of attaching cultured pig-liver cells to a plastic plate laced with hollow fibres that deliver oxygen to the cells. The cells are allowed to grow as a "sheet" across the plate and a group of plates can be stacked together to provide a working external liver for the patient.

They also found they could freeze the plates and tissues for up to a month, suggesting that a "bank" of such plates could be held for when patients needed them. "We would like to be able to freeze the plates to develop a bank of liver cells to meet clinical demand," Dr Grant said.

The Strathclyde system has only been tested on animals, but a US version is already on the market and being tested there, she said. There was no evidence so far that any pig viruses present in the cells could transfer across to the patient, she added.

A new treatment for persistent wounds in the elderly also relies on material recovered from pigs, according to Dr Ian Kill, of Brunel University in London. This "biomaterial" contains the "scaffolding" of skin including collagen but no pig-skin cells. It encourages the growth of fresh tissues into the scaffold, Dr Kill said.

The system could be used to grow small blood-vessel replacements, bone, tendon, ligament and cartilage. It would be particularly useful for providing a bridge upon which to grow skin cells in elderly patients with leg ulcers, which could be very slow to heal.