Scientists are hoping skin grown in petri dishes will someday allow them to stop or reduce testing on lab rats and other animals.

Scientists have figured out a way to grow skin from stem cells in mice “organoids” that could change how scientific research is done in the future.

Researchers at Indiana University School of Medicine were able to take mouse pluripotent stem cells and manipulate them so they could grow skin, complete with hair follicles, in the lab.

“The skin is a complex organ that has been difficult to fully recreate and maintain in culture for research purposes,” Karl Koehler, PhD, assistant professor of otolaryngology-head and neck surgery at Indiana University School of Medicine, said in a statement. “Our study shows how to encourage hair development from lab grown mouse skin, which has been particularly troublesome for researchers to recreate in culture.”

This research is part of a growing field focused on tiny organoids created from stem cells.

Scientists are using stem cells from humans and animals and manipulating them to turn them into heart, liver, or skin cells. They become “tiny organs” they can study.

The research isn’t just an interesting biological party trick.

Creating these organoids could dramatically remake how experiments are peformed.

Drugs could be tested on neural organoids to see if they’re toxic before being tested on humans or animals.

Skin grown in a lab could potentially be used for burn patients or even to help patients who have gone bald or have alopecia.

Key to Koehler’s research is the fact that they figured out how to get the cells to divide into two layers — the epidermis and dermis — that mimic the skin. Hair forms between these layers.

Koehler also said in an interview that this kind of research could also dramatically alter the use of lab animals in experiments.

“If we can generate skin organoids from human stem cells, we may have a good replacement for some of the animal models that are used today for testing skin-related drugs,” he said. “At the very least, we may be able to lower the number animals used for research. Animal welfare is an important issue and maintaining large numbers of animals is very costly, so we are always looking for alternatives.”

Guo-li Ming, PhD, a professor in the department of neuroscience at University of Pennsylvania Perelman School of Medicine, has been studying organoids made from stem cells to mimic neural tissue.

She said the rise of organoids, increasingly made from human stem cells, can mean that scientists will get better results more quickly.

She explained that if scientists can create human neuron cells, they could potentially recreate neural tissue. This is virtually impossible to get from a living person.

“If we can study human neurons in the dish, then less mouse neurons in the dish are required,” she said. “In the end, human cells are more relevant, and there are clear differences in mouse cells and human cells.”

She said that in her work, they’ve been able model certain diseases faster, such as the Zika virus, to quickly see the disease’s effect on neural cells.

“That is, I guess, a clear example how we can use organoids to understand the mechanism” of the disease, she explained.

Other organoids that have been created include those that mimic liver, gut, and heart functions — with tiny heart organoids that can even “beat.”

But this new field is still in the early stages.

Many of these organoids lack key systems, such as the immune system, that could be important for testing certain drugs or disease models.

While Koehler’s research is still in the early stages, he points out that by figuring out how to turn stem cells into skin with hair follicles, researchers could potentially look at making other organoids that mimic things such as tear ducts, sinuses, and salivary glands.

“Our work may provide insight into how these tissues could be mimicked in cell culture,” he said.