A team of biologists has built a prototype 3D bioprinter that can create functional human skin, which could help bring an end to animal testing once and for all.

The researchers, from Universidad Carlos III de Madrid, the Center for Energy, Environmental and Technological Research and Hospital General Universitario Gregorio Marañón, say their lab-made skin can be used in transplants for burns victims or for the testing of chemicals, cosmetics and pharmaceuticals.

It closely replicates real human skin, featuring an epidermis-like external layer for protection, a thicker layer to act as the dermis and a layer made up of fibroblast cells that produce collagen, the protein that gives skin elasticity and mechanical strength.

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“Knowing how to mix the biological components, in what conditions to work with them so that the cells don’t deteriorate, and how to correctly deposit the product is critical to the system,” said researcher Juan Francisco del Cañizo.

3D-printed skin designed to be transplanted needs to be made from the patient's own cells, so their body doesn’t reject it.

“This method of bioprinting allows skin to be generated in a standardized, automated way, and the process is less expensive than manual production,” said Alfredo Brisac, the CEO of BioDan Group, a bioengineering firm that wants to commercialise the technology.

Meanwhile, for industrial uses such as chemical testing, the skin can be mass-produced from a batch of cells.