Lab-Grown Human Skin Created with Stem Cells Could Replace Animal Testing

Animal lovers are in for some good news. It turns out that scientists have created the first lab-grown human skin, which could potentially replace animal testing in labs. The new epidermis, the outermost layer of the skin, has functional permeability that's similar to real skin.

The epidermis forms a protective layer between the body and its external environment. It prevents water from escaping and toxins and microbes from entering. Yet actually creating a layer of skin has been difficult, especially when it comes to forming the functional barrier needed for drug testing. Until now, they've also been limited in producing an in vitro model for large-scale drug screening by the number of cells that can be grown from a single biopsy sample.

Now, researchers may have found a way around that. They used human induced pluripotent stem cells (iPSC) in order to produce an unlimited supply of pure keratinocytes, which is the predominant cell type in the outermost layer of the skin. These cells closely matched the keratinocytes generated from human embryonic stem cells (hESC) and primary keratinocytes from skin biopsies.

Using these new cells, the researchers created 3D epidermal equivalents to build a functional permeability layer. In other words, they created something similar to human skin that could potentially be used for drug testing.

"The ability to obtain an unlimited number of genetically identical units can be used to study a range of conditions where the skin's barrier is defective due to mutations in genes involved in skin barrier formation, such as ichthyosis (dry, flaky skin) or atopic dermatitis," said Theodora Mauro, one of the researchers, in a news release. "We can use this model to study how the skin barrier develops normally, how the barrier is impaired in different diseases and how we can simulate its repair and recovery."

The new, lab-grown skin could be used for future research. Because it's cost-effective, it offers an alternative lab model for scientists studying skin disorders.

The findings are published in the journal Stem Cell Reports.