THE old philosophy of "body heal thyself" has been given a new high-tech twist with a treatment for liver failure that uses bone marrow stem cells from the patient's own blood.
To obtain the cells, the patient is first given an injection of a chemical called granulocyte colony stimulating factor (GCSF), which stimulates their bone marrow to produce extra stem cells. After five days on the drug, the patient's blood is screened for cells bearing the surface protein CD34, which marks them out as stem cells. These are then extracted from the blood, concentrated and injected into the patient's portal vein or hepatic artery, both of which feed blood directly to the liver.
No one is sure exactly where these cells go or what they do, but they appear to home in on, and help repair, any liver damage. The liver function and general health of three out of five patients given the treatment improved significantly within two months of treatment, according to liver surgeon Nagy Habib of Imperial College London, who heads the team conducting the trial. He presented the findings at a seminar in London last month hosted by the London Regenerative Medicine Network. The two patients whose health did not improve showed no ill effects from the treatment.
One patient in his early 60s had a chronic condition called primary sclerosing cholangitis, which progressively damages the liver's bile ducts. "At the outset, he had jaundice, was vomiting blood and had ascites - swelling caused by fluid around the liver," Habib says. Two months later, his jaundice had disappeared, while levels of albumin - a marker of healthy liver function - rose to normal. Magnetic resonance scans showed that the swelling had also gone down.
“No one is sure exactly where these cells go or what they do, but they appear to home in on, and help repair, liver damage”
Habib's team are hopeful that they will gain approval to conduct a follow-up trial on 18 more people with liver disease. This time, Habib hopes to refine the technique by isolating specialised stem cells that he calls "livercytes" and multiplying them outside the body for around two weeks before re-injecting them. An added benefit of the treatment is that the stem cells can be harvested from the blood rather than from bone marrow, which is a painful procedure.
Other researchers in Japan are close to publishing the results of a similar trial on 10 patients using stem cells to treat liver failure (New Scientist, 18 December 2004, p 6), though their technique involves extracting the cells directly from the bone marrow.
From issue 2520 of New Scientist magazine, 08 October 2005, page 13