TBO.com - TBO is Tampa Bay Online

Blood Vessels Grown From Patient Skin

ADVERTISEMENT

By LAWRENCE K. ALTMAN, The New York Times

Published: October 13, 2007

From a snippet of a patient's skin, researchers have grown blood vessels in a laboratory and implanted them to restore blood flow around the patient's damaged arteries and veins.

It is the first time blood vessels created entirely from a patient's own tissues have been used for this purpose, the researchers report in the current issue of The New England Journal of Medicine.
Cytograft Tissue Engineering of Novato, Calif., made the vessels, in a process that takes six to nine months. Because they are derived from patients' own cells, they eliminate the need for antirejection drugs. Also, because they are devoid of any synthetic materials or a scaffolding, they avoid complications from inflammatory reactions.

Doctors in Argentina have performed the first human tests of the vessels on six patients, the team reported. Two additional implants have been performed since the report was submitted, said Todd N. McAllister of Cytograft.

The longest follow-up among these patients has been for 13 months.

Cytograft says the vessels hold promise for patients with damaged blood vessels from diabetes, arteriosclerosis, birth defects and other problems. Monitoring for a much-longer period will be needed before those uses could become standard, the team said.

'This technique has a big potential in the vascular surgical field,' said Toshiharu Shinoka, who directs pediatric cardiovascular surgery at Yale and who plans to conduct studies with Cytograft on the new vessel.

He called the technique an advance over one he used in operations on children in Japan, in which vessels were grown from cells on a scaffold that then degraded and was absorbed into the body.

Doctors not connected with the company agreed on the importance of the new technique.

'A potential benefit may be for infants and children with congenital heart defects,' said Deepak Srivastava, director of the Gladstone Institute of Cardiovascular Disease at the University of California, San Francisco.

Unlike grafts from cadavers, he added, 'the Cytograft vessels should be able to grow as the child does.'

The Cytograft team plans to publish a full report of the findings from its trial after 10 patients have been monitored for six months. Cytograft has applied to the Food and Drug Administration for approval to conduct tests of the vessels in the United States.

The Cytograft studies were conducted at a leading cardiovascular center in Argentina, where medical costs are much lower than in the United States.

The patients were all receiving chronic kidney dialysis, which cleanses wastes from the blood.

As is standard for such treatment, doctors had surgically cut an artery and a vein in the forearm and joined them in a link known as a shunt, which provides access for the repeated needle punctures needed to connect a patient to a dialysis machine. Such shunts can last up to 15 years. When clots and infections develop in the shunts to reduce or stop blood flow, however, new ones must be created.

Share this:

Loading Comments...

Email Print

ADVERTISEMENT