Wellington, Dec 10 NZPA - Australia's decision today to lift its ban on implanting animal tissues in humans may cost New Zealand a share of its cutting-edge research into using pig cells, says a company doing trials here.

The Australian national health and medical research council (NHMRC) today announced it will lift a five-year ban on clinical trials of animal-to-human "xenotransplants" once robust regulations, oversight and monitoring are set up, with a surveillance strategy and lifetime registration of patients.

In 2005, the New Zealand government recommended that xenotransplantation trials proceed on a case-by-case basis, and such transplants were started in Auckland by Australian-listed company Living Cell Technologies (LCT).

The company is running a clinical trial at Middlemore Hospital treating eight diabetics with insulin-producing pig cells.

The company's medical director, and co-founder, Bob Elliott said today he welcomed the Australian decision.

"It will allow us to apply for a clinical trial in Australia, which we will do quite quickly," he said. "It opens the door for us being able to get on and try some of the other cell types we have been planning."

It wants to start testing the safety of brain cells from piglets injected straight into the brain of primates to see if they can be used as a therapy for Parkinson's disease. Research on both brain and islet cell transplants from pigs was supported by New Zealand taxpayers.

Primate studies would have to be done overseas because New Zealand requires specific ministerial approval for experimentation on chimpanzees and other primates. Trials have already been done on a laboratory rat "model" for Parkinson's, which improved limb function.

Parkinson's disease -- caused by degeneration of the cells in the brain that regulate dopamine -- causes muscle tremors and conventional treatments with dopamine replacement fade over time.

The company has also been investigating whether human liver cells grown in test tubes may be able to stop uncontrolled bleeding in haemophiliacs, and Prof Elliott has said the company has tried brain choroid plexus cells and liver cells:"There are many other cell types we could use".

The researcher trained as a paediatrician at Adelaide University and said a few months ago that the company would want to move research to Australia, once the ban there was lifted.

"We'd certainly be wanting to shift across the Ditch," he said as LCT geared-up for the Middlemore trials implanting islet cells from the pancreas of newborn piglets into eight human diabetics, to manufacture insulin.

The company wraps the cells in a seaweed gel so that they are not detected by the patient's immune system and rejected, avoiding the necessity for immunosuppressive drugs. The piglets, farmed in quarantine at Invercargill for their tissues, are descended from feral animals brought back after the species was isolated on the Auckland Islands for over 150 years.

It has already reported promising progress with its first patient, a 48-year-old man. The trial is being run by Middlemore endocrinologist John Baker, who is director of the clinical trials unit at the Centre for Clinical Research and Effective Practice, in Auckland,

Prof Elliott first carried out such trials on humans in Auckland in 1996, until they were shut down by medical authorities, who also blocked the trials being re-started in Rarotonga.

LCT was later listed on the Australian stock exchange to fund monkey trials in Singapore but only got one of eight animals off insulin: "We think the primate model is severely flawed," Prof Elliott later said.

The trials in Moscow and Auckland may allow him to show Australian authorities evidence of safety in humans, rather than chimpanzees.