Four teenage girls received vaginal organs that were engineered with their own cells, according to a new pilot study published in The Lancet.
The research team led by Anthony Atala, M.D., director of Wake Forest Baptist Medical Center’s Institute for Regenerative Medicine in Winston-Salem, N.C. , is the first to demonstrate that vaginas can be constructed in the lab and used successfully in humans.
“This may represent a new option for patients who require vaginal reconstructive surgeries. In addition, this study is one more example of how regenerative medicine strategies can be applied to a variety of tissues and organs,” Atala says in a news release.
The girls in the study were born with Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome, a rare genetic condition in which the vagina and uterus are underdeveloped or absent.
The treatment could also potentially be applied to patients with vaginal cancer or injuries, according to the researchers. Current treatments for MRHK syndrome include dilation of existing tissue or reconstructive surgery to create new vaginal tissue.
A variety of materials can be used to surgically construct a new vagina – from skin grafts to tissue that lines the abdominal cavity. However, these substitutes often lack a normal muscle layer and some patients can develop a narrowing or contracting of the vagina, the researchers note.
The researchers say that with conventional treatments, the overall complication rate is as high as 75 percent in pediatric patients, with the need for vaginal dilation due to narrowing being the most common complication.
The girls in the study were between 13 and 18 years old at the time of the surgeries. Data from annual follow-up visits show that even up to eight years after the surgeries, the organs had normal function. In addition, the patients’ responses to a Female Sexual Function Index questionnaire showed they had normal sexual function after the treatment, including desire and pain-free intercourse.
The organ structures were engineered using muscle and epithelial cells from a small biopsy of each patient’s external genitals. In a Good Manufacturing Practices facility, the cells were extracted from the tissues, expanded and then placed on a biodegradable material that was hand-sewn into a vagina-like shape. These scaffolds were tailor-made to fit each patient.
About five to six weeks after the biopsy, surgeons created a canal in the patient’s pelvis and sutured the scaffold to reproductive structures. Previous research had shown that once cell-seeded scaffolds are implanted in the body, nerves and blood vessels form and the cells expand and form tissue. At the same time the scaffolding material is being absorbed by the body, the cells lay down materials to form a permanent support structure – gradually replacing the engineered scaffold with a new organ.
Follow-up testing on the lab-engineered vaginas showed the margin between native tissue and the engineered segments was indistinguishable and that the scaffold had developed into tri-layer vaginal tissue.
Before beginning the pilot clinical study, Atala’s team evaluated lab-built vaginas in mice and rabbits beginning in the early 1990s. In these studies, scientists discovered the importance of using cells on the scaffolds. The team used a similar approach to engineer replacement bladders that were implanted in nine children beginning in 1998, becoming the first in the world to implant laboratory-grown organs in humans. The team has also successfully implanted lab-engineered urine tubes (urethras) into young boys.