Ammon News - Researchers in the US have 3D-printed hair follicles in human skin tissue for the first time.

While actually growing hair is still likely "several years away", it is a major step forward and also a boost for drug testing and skin grafts.

Dr Pankaj Karande, an associate professor of chemical and biological engineering who led the study, said: "Our work is a proof-of-concept that hair follicle structures can be created in a highly precise, reproducible way using 3D-bioprinting.

"This kind of automated process is needed to make future biomanufacturing of skin possible.

"The reconstruction of hair follicles using human-derived cells has historically been a challenge.

"Some studies have shown that if these cells are cultured in a three-dimensional environment, they can potentially originate new hair follicles or hair shafts, and our study builds on this work."

Hair follicles help maintain moisture, regulate body temperature and house stem cells that help the skin heal when it's injured.

They are also how topical drugs and cosmetics enter the body.

A team at Rensselaer Polytechnic Institute in New York wanted to find a way to create follicle-bearing skin using 3D printing techniques at a cellular level.

They allowed samples of skin and follicle cells to divide and multiply in the lab until they had enough to print.

Each type was then mixed with proteins and other materials to create the "bio-ink".

Skin was then printed layer by layer using a very thin needle, while channels were also created to deposit hair cells.

The current lifespan of these tissues is two to three weeks, which isn't enough time for hair shafts to develop.

But researchers hope to extend this period, allowing the follicle to mature further and eventually grow hair.

Dr Karande said: "We have now shown that we can incorporate collections of cells, which are the precursor for forming hair follicles.

"We can embed them within the skin using 3D printing. And if we provide them the right kind of conditions, growth factors and nutrients, and we wait just long enough, these cells can actually start self-assembling to form these early follicular structures.

"You see this very typical sort of bulb-shaped structure starting to form on the skin, which should eventually lead to the formation of hair."

The findings, described by first author Dr Carolina Catarino as "exciting", were published in the journal Science Advances.

The Sun