New research published in the journal Nature this week describes how a team of scientists were able to culture multi-layered skin tissue that has the potential to grow hair, secrete sebum, and be sensitive to touch. The petri-dish-grown organoid took about 4-5 months to develop and offers exciting new opportunities for disease monitoring and reconstructive surgery.

As the largest of the human body’s organs, skin looks plain enough on the surface but is actually a highly complex tissue made up of several layers and cell types. It keeps us warm, allows us to sweat and cool down, it sheds and heals, and keeps bacteria and unwanted moisture out. It might have plagued you during your teenage years, but skin really is marvelous.

For all its incredible complexities, however, skin is a nightmare to create in the lab and previous attempts to culture the wonder-organ and all its associated structures outside of the human body have posed a major biomedical challenge. Enter, Karl Koehler colleagues who announced this week that they have successfully developed an organoid culture system that uses human pluripotent stem cells to create skin organoids.

These petri dish organoids took around 4-5 months to develop in special growing conditions but once finished were found to exhibit a distinct epidermis and dermis layer, hair follicles, sebaceous glands, and even an interwoven nerve circuitry. They then transplanted the skin organoids onto the back skin of immunocompromised mice (without immunosuppressants such transplants are usually rejected quite swiftly by the body) and it was found that 55 percent of the grafts carried out grew hairs. This discovery reveals that the petri dish skin could tolerate and integrate being transplanted onto a living animal, in this case of a different species as the stem cells were of human origin, and successfully carrying out their function in situ.

The researchers urge that while an exciting achievement, there is still some way to go before the therapeutic approach can be integrated into human medicine. The potential applications indicate that the discovery could open up major opportunities for disease modeling, treatment of hair loss, and vastly improve the outcome of reconstructive surgeries that currently rely on autografts or cadaver donors, which risk rejection.

“The work holds great promise of clinical translation,” said Leo Wang and George Cotsarelis in a Nature News & Views article. “We are confident that research will eventually see this promise realized.”