Two new studies describe the latest achievements in growing body parts in a lab and transplanting them into people, this time with nostrils and vaginas.
Windpipes, bladders, blood vessels and other structures have previously been created in part from a patient’s own cells and then implanted. Eventually, scientists hope to tackle more complicated things like lungs and kidneys with this strategy, which is aimed at avoiding rejection of transplanted organs.
The latest experiments were published online Friday in the journal Lancet.
“They both show that by using fairly simple tissue engineering techniques, you can get real tissue forming where it’s supposed to,” said Dr. Martin Birchall, of The Ear Institute at University College London, who co-authored an accompanying commentary. He said the simple methods could be useful for making other body parts, including joint cartilage, bowels and the esophagus.
One experiment involved four teenage girls in Mexico who were born without vaginas because of a rare disorder. Currently, surgeons use tissue grafts to create vaginas for such patients, but that method carries a risk of complications.
The experimental results were reported by Dr. Anthony Atala of the Wake Forest University School of Medicine in Winston-Salem, North Carolina, with researchers there and at the Metropolitan Autonomous University in Mexico City. Atala said the procedure might also prove useful for replacing vaginas removed because of cancer, and repairing or replacing the organ after an injury.
For the experiment, researchers took a tissue sample less than half the size of a postage stamp from the patients’ genitals. They multiplied cells from this tissue in the lab, seeded them onto a biodegradable scaffold and molded it into the right size and shape for each patient before implantation.
The first surgery was done in 2005, and the Lancet report provides a follow-up of the patients for an average of nearly seven years. The women report normal levels of sexual functioning, without any long-term complications. It is not known whether the women could get pregnant; only two have wombs, Atala said.
One of the women, in a video provided by the Mexican university, said she felt fortunate “because I have a normal life.” The university didn’t identify the woman.
In the other experiment, Swiss scientists built new outer nostrils for five patients who had skin cancer on their noses. When surgeons removed the tumor, they also took a tiny bit of nose cartilage. They grew the cells for four weeks in the lab to make a small flap. That was then implanted onto their nose and covered with skin from their foreheads. Normally, cartilage is taken from the patient’s ear or ribs to recreate the nostril.
Ivan Martin of University Hospital Basel, the study’s senior author, said none of the patients reported any side effects by one year after surgery, and all were satisfied with their new nostrils.
“Now that we have demonstrated this is safe and feasible, we can use (this technique) for more complicated clinical needs,” he said, adding that the same approach is being tested in people to supply knee cartilage. He said scientists were slowly gaining more expertise in making body parts, but predicted it could take another couple of decades before the process becomes mainstream.
“It’s not a trivial thing to engineer a functional tissue,” he said.
Story From Newsweek:
For the first time, researchers have successfully implanted laboratory-grown vaginas in human patients—potentially helping women avoid drawbacks from other regenerative procedures, scientists announced in a paper published today.
A research team at Wake Forest Baptist Medical Center’s Institute for Regenerative Medicine, led by Dr. Anthony Atala, said in Lancet that four recipients of lab-grown reproductive organs underwent surgery between June 2005 and October 2008—and that the organs are functioning normally after eight years. The new organs are created by culturing these women’s own cells into tissues and eventually reshaping the tissues into a vagina-like structure.
An underdeveloped or absent vagina can result from any number of health problems, ranging from congenital syndromes like Mayer-Rokitansky-KÃ¼ster-Hauster (MRKH) to cancers and injuries. Though there are other methods of reconstructing vaginas for women with these problems, those procedures can have big drawbacks.
The first-line method is dilation—gradually expanding an undeveloped opening—works 90 percent of the time. The 10 percent of women for whom it’s not successful can seek treatment via several surgical procedures, Dr. Marc Laufer, chief of the Division of Gynecology at Boston Children’s Hospital, tells Newsweek.
These procedures use the women’s tissues, such as skin from their buttocks or intestinal tracts, to reconstruct vaginal organs. But the result isn’t always ideal—the transplanted skin doesn’t act like a normal vagina would.
Atala has come up with a better method. His team creates the vaginal organs using muscle and epithelial cells (“the cells that line the body’s cavities,” they explain) taken from the patient’s external genitals. The researchers culture these cells—a biopsy sample less than half the size of a postage stamp—so that more and more would grow. After about four weeks, researchers place them “on a biodegradable material that was hand-sewn into a vagina-like shape” so they grow into a form a bit like a champagne glass, Atala says.
Some seven days later, surgeons suture this structure, which they call a “scaffold,” to patients’ existing internal reproductive organs. After implantation, nerves and blood vessels form, and the cells on the scaffold “expand and form tissue.” While the body begins to absorb the biodegradable scaffold, “the cells lay down materials to form a permanent support structure—gradually replacing the engineered scaffold with a new organ.”
The four patients, who were not immediately available for comment, have reported positive results. In a questionnaire on female sexual function, the women said they had “normal sexual function after the treatment, including desire and pain-free intercourse.”
The girls in the study were born with MRKH, a congenital condition “in which the vagina and uterus are underdeveloped or absent,” according to the National Institutes of Health. MRKH is fairly rare, affecting approximately 1 out of every 4,500 newborn girls.
In a conference call with reporters, Atala said the method might work for conditions other than MRKH, such as vaginal cancer or injury. The research team focused only on MRKH patients because that allowed for a controlled experimental group, he said.
There are limits to this research. The team admits that the study, while exciting, is quite small in scale and that the technique needs to be performed more “to compare it with established surgical procedures.”
This is not the first time Atala’s team has created organs in labs with similar methods. Starting in 1998, an Atala-led team created replacement bladders and implanted them in nine children, making the team “the first in the world to implant laboratory-grown organs in humans.” The team has also implanted lab-made urethras into young boys. In February, scientists at the University of Texas Medical Branch created lab-grown lungs, according to reports. In addition, scientists in England are working on making noses, tear ducts and blood cells in a lab, The Associated Press reports.
Some MRKH-patient advocates were enthused about the news.
“It’s a start creating something that’s less invasive,” Amy C. Lossie, president and CEO of the Beautiful You MRKH Foundation, tells Newsweek. “Anything that’s going to heal quicker and result in fewer complications is a good step forward.”