Researchers from Northwestern University have successfully removed mouse ovaries and replaced them with 3D-printed ones. The mice were able to ovulate, mate, give birth to healthy pups, and nurse them.
This technique, or one similar to it, could one day be used to help women with infertility.
The researchers used a 3D printer with a nozzle that fired gelatin, derived from the collagen naturally found in the ovaries. The scientists built the ovaries by printing various patterns of overlapping gelatin filaments to form a scaffolding to hold ovarian follicles containing eggs.
A microscopic view of the gelatin structure used to 3D print the bioprosthetic mouse ovary implant. (Credit: Northwestern University)
Each scaffold measured just 15 by 15 millimeters. The scientists inserted mouse follicles (spherical structures containing a developing egg surrounded by hormone-producing cells) into these scaffolds. The 3D-printed ovaries were then implanted into the mice.
After a week, veins had grown throughout the artificial ovaries, and there were signs of native mouse cells migrating into the ovaries. The follicles also started to produce several hormones as they began to ready eggs for release, indicating that the menstrual cycle was proceeding.
Of the seven mice that received 3D-printed ovaries, three birthed litters, and those mice went on to have children of their own. The mothers were also able to lactate, a process controlled by progesterone secreted by glands in the new ovaries.
Such bioprosthetic ovaries could one day be implanted in human patients to restore fertility, using a patient’s own previously extracted follicles with eggs. However, that is still likely a long way off.