Doctors in Sweden have replaced a vital blocked blood vessel in a 10-year-old girl using the first vein grown in a lab from a patient's own stem cells.
The successful transplant operation, reported online in The Lancet medical journal on Thursday, marks a further advance in the search for ways to make new body parts.
It could open the door to stem cell-based grafts for heart bypass and dialysis patients who lack suitable blood vessels for replacement surgery, and the Swedish team said it is now working with an undisclosed company to commercialise the process.
"I'm very optimistic that in the near future we will be able to get both arteries and veins transplanted on a large scale," said Suchitra Sumitran-Holgersson, professor of transplantation biology at the University of Gothenburg, and a member of the team that performed the operation in March 2011.
The advantage of using tissue grown from a patient's own cells is that there is no risk of organ rejection and hence no need for lifelong immunosuppressive drugs.
Four years ago, a 30-year-old woman received the world's first transplant of a tailor-made windpipe, grown in a similar way by seeding a stripped-down donor organ with her own stem cells. Other such trachea operations have followed since.
The latest case involved a young girl with an obstructed hepatic portal vein, which drains blood from the intestines and spleen to the liver. Its blockage can be fatal.
The team from the University of Gothenburg took a 9 cm (3.5 inch) section of groin vein from a deceased donor and removed all the living cells, leaving just a protein scaffold tube. Stem cells extracted from the girl's bone marrow were then injected onto the tube and two weeks later the graft was implanted.
The new blood vessel immediately restored normal blood flow, the doctors said, although after a year it narrowed and a second stem cell-based graft was needed.
Martin Birchall and George Hamilton of University College London said in a commentary in The Lancet that the Swedish doctors had spared the young girl the trauma of having veins harvested from deep in her neck or leg and avoided the need for a liver transplant.
But they cautioned the technique now needed to be tested in clinical trials and developed into a straightforward quality-controlled production process.
Sumitran-Holgersson said her team had already simplified the process and was now able to harvest stem cells from blood rather than bone marrow. She aims to test the technique with arteries later this year.
"You are going to see more and more of these personalised grafts in future," she said in a telephone interview.
The university has also linked up with a Swedish company, which Sumitran-Holgersson declined to identify, to explore how to commercialise the technique. This could involve offering "off-the-shelf" scaffolds from which tailor-made blood vessels could then be built.
Around the world, scientists in the emerging field of regenerative medicine are working to engineer many different human organs and tissues in the lab, including lungs and hearts.
Building such complex organs is a lot more challenging than making blood vessels, however, since veins are relatively simple hollow structures with few engineering demands.
US records more deaths from drug, alcohol overdoses than car accidents
Paris being hit by the longest and most intense winter pollution peak in 10 years, according French air quality watchdog
A third of the world's polar bears will disappear in next 40 years
About 20 percent of Canadians have little or no coverage
Students in a private Australian high school have recreated a malaria drug in the school laboratory
2 studies claim psilocybin, outlawed by federal government, could significantly improve patients’ mood
Global crises changing nature of hotel industry, expert warns Mediterranean Week of Economic Leaders conference
Fighting climate change means different things in different cities, as this snapshot illustrates:
The Paris deal, now in force, calls for capping global warming at two degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial levels, and at 1.5 C (2.7 F) if possible.
British MPs voted in February to allow the creation of in-vitro fertilisation (IVF) babies with DNA from three people.
The H5N6 virus was first confirmed on November 18 at a farm in central South Korea and it has since spread to farms around the country, with the total number of cases now standing at 46.
It is one of the biggest clinical trials involving the disease ever undertaken and has revived hopes in the scientific community of a breakthrough in the battle against AIDS.
Nuclear energy: who's advancing and who's retreating
A killer bird flu that is sweeping Europe has forced Sweden to cull more than 200,000 chickens
Study finds blood of old mice makes young mice feeble; scientists hope to discover more in human trials soon
Drug overdoses are now killing more Americans than car crashes, putting the sheer scale of the crisis into perspective.