Scientists in Sweden are reporting a medical first: a vein grown in a lab for a 10-year-old girl using her body's own cells.
Doctors are hailing the step as a milestone in tissue engineering, a field in which doctors grow windpipes, bladders, lungs and other organs to replace faulty ones while avoiding the dangerous, lifelong complications of organ transplants.
While a handful of doctors around the world have had success growing blood vessels and other organs and transplanting them into patients, doctors said this is the first time a vein has been lab-grown and successfully transplanted using cells and parts taken entirely from the human body.
"To many of us working in this field, it is a validation of what we believe will be a revolution in medicine," said Dr. Adam Katz, director of plastic surgery research at the University of Florida.
Suchitra Sumitran-Holgersson, one of the authors of a report on the transplant published today in the Lancet journal, said the experimental procedure could someday bring promise to patients needing new blood vessels for dialysis or coronary bypasses.
"It is very difficult to find suitable arteries and veins to use for these patients," she said. "It would be good to create a personalized artery and vein for them."
Sumitran-Holersson and her colleagues grew the vein for a 10-year-old girl who had a blockage in the vein connecting her intestines and spleen with her liver. The rare condition can cause life-threatening bleeding, delayed development and even death. The patients often need a graft of a vein to replace the blocked one.
But traditional vein grafts are complicated. Doctors usually cut deep into patients' legs or necks to harvest their own veins to replace defective ones elsewhere, putting the patients at risk of an additional, traumatic surgery. Another option is using man-made vessels as replacements, but those are prone to dangerous clots and blockages and virtually guarantee that the patient will need a lifelong course of drugs to keep their immune system from attacking the vessel.
In this new approach, doctors took about 3.5 inches of a vein from the groin of a 30-year-old deceased donor and, in the lab, scraped away all of the donor's cells, leaving just the protein scaffolding of the vein. Doctors then took cells from the bone marrow of the 10-year-old girl and seeded the vein scaffolding with them. Then, for two weeks, they waited for the cells to grow.
The result was a blood vessel engineered entirely from human tissue. When surgeons took the vein and used it to replace the faulty vein leading to the girl's liver, normal blood flow was restored almost immediately, the researchers said.
The vessel had to be repaired after nine months when hardened scar tissue in the girl's body put too much pressure on the transplanted vessel.
A year after the transplant, the girl has grown nearly 2.5 inches, gained 11 pounds and has even taken up light gymnastics. So far, her body also shows no signs that it will reject the vein. But doctors will have to make sure that the vein and the liver stay healthy.
"When we met her last week, she was somersaulting and talking away," Sumitran-Holgersson said. "So far, she is doing very well."