The increasing number of middle-aged patients with chronic liver disease caused by heavy drinking is forcing doctors to look at new ways of saving their lives.
In the UK, a pioneering trial to help seriously ill people will begin this month, using the patient's own cells to regenerate the organ.
By injecting patients with their own stem cells, the basic "building blocks" for all kinds of cells, doctors hope that the liver can regrow itself to a point where the organ starts to work again.
The trial is experimental, but follows other work which shows that stem cells have helped patients with heart failure. The shortage of donor organs for transplant has encouraged the specialists to think of new ways of helping patients who otherwise have a very bleak future.
Scientists at Imperial College London believe stem cell therapy holds out enormous hope for those who need new organs.
"The liver is a wonderful organ in the way it can regenerate itself, but if there is a lot of damage it stops functioning properly. If we can get 15 to 20 percent of the organ regenerated, then that is enough to really improve the patient's condition. These cells seem to have the fantastic ability to become whatever is needed in order to repair the damage," said professor Nagy Habib, head of liver surgery at London's Hammersmith Hospital, who is running the trial.
By injecting the patient's own stem cells, taken from their blood, directly into the bloodstream, the researchers hope they may be able to improve the function of the liver by getting the stem cells to repopulate the organ.
The procedure, known as leukapheris, involves taking
blood from a patient and then separating it into its component parts.
The stem cells are taken from the white blood cells, while the red blood cells are returned to the body through the arm. Habib and his team then inject the stem cells into the hepatic artery, the vessel which goes into the liver.
It is not yet known how many stem cells may be needed for the trial to succeed. The worse the patient's liver function, the more cells may be necessary.
"If you can provide one percent of liver cell mass, and then allow that one percent to grow over a three-month period, it's possible that the liver will have enough healthy cells to behave properly, and start to produce what it needs," Habib said.
Like many specialists, he worries that people do not understand the damage that can be done by heavy, prolonged drinking.
When alcohol is drunk, it is quickly absorbed and passes in the bloodstream to the liver, where it can cause excessive fat to be deposited within the liver cells.
Cirrhosis, when healthy liver tissue is gradually replaced by scarred, useless tissue, is insidious, vbecause apparently healthy people may have it without knowing and the first signs do not occur until a late stage of the disease. Although alcohol is the leading cause of cirrhosis, it can also be brought on by forms of hepatitis or by some toxic chemicals.
Between 20 and 30 percent of those who drink heavily beyond the initial stages of liver damage will develop alcoholic hepatitis, a condition which can be fatal. A smaller number, about 10 percent, go on to develop cirrhosis.
"If people could see what life was like in the final stages of liver failure, they might think seriously about giving up at a much earlier point. The liver is a very forgiving organ, but there's a limit to how much alcohol it can process before the damage sets in," Habib said.