NEW YORK CITY — Scientists have discovered a new way to grow human hair in the lab using 3D-printed molds.
According to a Columbia University news release, researchers used 3D-printing to create a plastic mold with long, thin extensions half a millimeter wide, and designed to mimic the natural microenvironment of human hair cells.
Once human skin is engineered to grow around the mold, hair follicle cells are seeded in and topped by keratin-producing cells.
They are then fed a cocktail of growth factors that stimulates hair growth. This includes JAK inhibitors, which were found to reawaken resting hair follicles in mice when applied on the skin.
Researchers had previously discovered a pathway called JAK-STAT in the stem cells of resting hair follicles that keeps them in a dormant state. By controlling pathway activity, JAK inhibitors can trigger follicle growth.
According to the Columbia researchers, human hair follicles appeared after three weeks and started creating hair.
The technique will be especially useful for hair restoration surgery, which currently relies on the redistribution of follicles from one part of the body to another.
Using this new method, scientists can create “a grid of hairs that are patterned correctly and engineered so they can be transplanted back into that same patient’s scalp.”
Hair follicles grown this way could allow for an unlimited supply, with no need for donor hair grafts.