A group of scientists discovered a way to replace a mouse’s ovary with a 3D printed one. The 3D printed ovary allowed an infertile mouse to mate and breed two pups. The findings were published in a paper in the journal Nature Communications on May 16.
Researchers from Northwestern University were able to successfully print the 3D mouse ovary by creating it from its own ovarian follicles.
Bioprosthetic ovaries enabled mice to give birth to pups
The researchers found that using the bioprosthetic ovaries, mice were able to ovulate, mate, give birth to mouse pups, and nurse them.
“The idea that a young cancer patient who has to undergo chemotherapy would have an ovary taken out before the first sterilization treatment, that tissue preserved, her ovarian follicles isolated and then when she’s ready we could give her a new ovary,” said Teresa Woodruff, a reproductive scientist and director of the Women’s Health Research Institute at Northwestern, according to Gizmodo.
Woodruff believes the 3D printed bioprosthetic ovary is the holy grail of regenerative medicine and added that the long-term goal of the study is to help cancer patients. The researchers, including Ramille Shah, an assistant professor of materials science and engineering at McCormick School of Engineering, hope the study will help restore fertility in women who underwent cancer treatments that left them sterile.
In recent years, other studies have successfully printed 3D replicas of mice ovaries. However, human ovaries are larger than mice’s, so experts have raised their concern on the materials used to recreate a mouse ovary, and whether they would work the same on humans.
“Our real advance here was to use gelatin, a biomaterial that makes up most of our soft tissue, and make and ovary proxy,” said Woodruff, according to Gizmodo. “That’s going to be important for the whole field of tissue engineering.”
The researchers created a structure that was rigid enough to stand up to surgery and which was porous enough to work with the mouse’s body tissues. Woodruff and her team found that the pattern in which the 3D ovary was printed had a significant impact on whether the bioprosthetic ovary actually worked.
Mice were able to breed, give birth and lactate with the 3D ovaries
The process was complicated, as the scientists first had to remove the mice’s ovaries to sterilize them, then they preserved the ovarian tissue and isolated its hormone-producing cells, which support immature eggs. They used a 3D printer and gelatin to print the basic structure of the ovary and dosed it with the cultured ovarian follicles.
The printed ovaries were then surgically transplanted back into the mice, and once they adapted to their bodies, the egg cells began to mature and ovulate. Blood vessels formed in the mice, which allowed hormones to circulate within their bloodstream to take care of all the other stages of pregnancy, such as lactating after birth.
The mice underwent a healthy pregnancy and eventually gave birth to mouse pups. The pups were engineered to glow, as a method to keep track of which of them were born from mothers with the bioprosthetic ovaries. According to Woodruff, the ultimate goal was not just to allow women to get pregnant with bioprosthetic organs, but to also restore the total health of a woman’s endocrine system.
“Some people just think of the ovary as fertility,” noted Woodruff. “But it’s more than that. It’s part of the overall system of a woman’s health.”
The new study from Northwestern University may be one of the most realistic approaches to restore and improve fertility in women. The method has proven to work in mice, and researchers now expect to find a way to translate those results into humans.
Human trials could begin sometime in the next ten years
Woodruff noted she hopes to address some of the challenges soon, such as finding a printing method that ensures the best chances of the egg cells maturing, as well as discovering a material that will create sustainable organs in humans.
It is not the first time that Woodruff’s team has investigated women’s fertility. Earlier this year her team used tissue cultures to create a miniature 3D model of women’s reproductive track, dubbed a “period on a dish.” They managed to successfully grow immature egg cells into mature ones in a laboratory. However, federal funding rules have prevented Woodruff from carrying that research any further and fertilizing the egg to observe how it continues to develop, but she noted she is looking non-government funding to keep it.
Woodruff and her team’s next step is to test the bioprosthetic ovaries in pigs, and she noted there is still a fair amount of work to be done before the experiment can be conducted in humans. However, she added that it won’t be too far in the future, as she believes it can be performed sometime in the next ten years.
Source: Nature Communications