Scientists from the Wake Forest Institute for Regenerative Medicine (WFIRM) were able to show that bioengineered uteri in an animal model developed the native tissue-like structures needed to support normal reproductive function. With further development, their finding may provide a treatment option for women with uterine infertility.
Their study, “A tissue-engineered uterus supports live births in rabbits,” was published in Nature Biotechnology and led by Anthony Atala, MD, director of WFIRM.
“The study shows that engineered uterine tissue is able to support normal pregnancies, and fetal development was normal, with offspring size and weight being comparable to those from a normal uterus,” Atala noted.
“In large animal models, reconstruction of the uterus has been demonstrated only with xenogeneic tissue grafts. Here we use biodegradable polymer scaffolds seeded with autologous cells to restore uterine structure and function in rabbits,” the scientist noted.
Scientists implanted biodegradable scaffolds into the damaged uteri of 78 rabbits. The rabbits were assigned to four groups: The first group was a tissue-engineered uteri group that received a cell-seeded scaffold using the animals’ own cells; the second group was a non-seeded scaffold group, that received a polymer scaffold only; the third group was a subtotal uterine excision-only control group, where the subtotal excision was repaired by suturing; the final group was a control group, where the rabbits underwent a sham surgery.
“At six months postimplantation, only the cell-seeded engineered uteri developed native tissue-like structures, including organized luminal/glandular epithelium, stroma, vascularized mucosa, and two-layered myometrium. Only rabbits with cell-seeded constructs had normal pregnancies (four in ten) in the reconstructed segment of the uterus and supported fetal development to term and live birth.
“This research introduces new avenues for potentially creating tissue substitutes derived from a patient’s own cells to treat uterine defects,” noted co-author Renata S. Magalhaes, MD, PhD. “Our results indicate that the tissue-engineered uteri responded to the expansion and mechanical strains that occur during pregnancy,” said co-author J. Koudy Williams, DVM. “Further preclinical studies are being planned before clinical trials are contemplated.”
In the United States, fewer than 10 babies have been born via a transplanted uterus. This strategy avoids the need for a transplanted organ from a deceased or living donor, and avoids the risk of rejection. Further studies are needed before clinical trials are contemplated, but this strategy holds promise for women with uterine infertility.