Bone Marrow Grafts Treat Blocked Leg Vessels
Study: Patients can help ailing limbs with their own cells
THURSDAY, Aug. 8, 2002 (HealthDayNews) -- Your own bone marrow cells could one day help treat blocked arteries in your legs.
Japanese researchers have discovered that so-called autologous bone marrow transplants taken from and then administered to patients with artery problems eased their pain, enhanced mobility, and improved other symptoms of seriously blocked blood flow to the legs.
That condition, called critical ischemia, occurs when the arteries in the limbs narrow. It can cause excruciating discomfort, walking woes, and ulcers.
Limb ischemia is often the result of peripheral arterial disease, a malady that leads to 35,000 amputations each year in the United States. Smoking, diabetes, and heart disease are three of the chief risk factors for the problem.
Doctors treat some patients with drugs and bypass surgery to reroute blood flow around the backup, but not the most severe cases. Researchers have been working on other treatments for the disease, including gene therapy.
"We're very much in the process of developing creative, novel ways to solve the problem of bad circulation," says Dr. Robert Schainfeld, a Tufts University blood vessel expert.
The latest work, which appears in the Aug. 10 issue of The Lancet, falls into that category, Schainfeld adds.
A team led by Dr. Eriko Tateishi-Yuyama of Kansai Medical University in Osaka first tested marrow transplants in 25 older men and women with one ischemic leg. The grafts contained mononuclear cells, which include immune agents and "endothelial progenitor" cells integral to the formation of vessel lining.
Endothelial progenitors belong to a line of stem cells with the capacity to direct the growth of new vessels, a process known as angiogenesis. Earlier research has found that grafts of these cells also lead to local increases in certain chemicals that promote angiogenesis.
In a subsequent test, Tateishi-Yuyama's group repeated the procedure in 22 other volunteers with the condition in both legs, giving them injections of their own marrow in one limb and mononuclear cells from blood in the other as a control.
Overall, 39 of 45 patients who received the bone marrow grafts reported improvements in pain and other limb symptoms, the researchers say, and 30 had substantial gains.
Fifteen of 20 patients scheduled to have a toe amputated no longer needed that procedure, and leg ulcers got better in six of 10 people with the lesions. In some cases, the size and severity of the ulcers were dramatically reduced.
Imaging tests revealed webs of new vessel growth in the legs, suggesting that the improvements were related to greater blood flow in the limbs.
"Implantation of bone marrow-mononuclear cells could be a safe and effective strategy for achievement of therapeutic [vessel growth]," the researchers wrote in the journal.
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