In a first, scientists have developed a new 3D bioprinter that can create fully functional human skin, which can be used for transplants as well as testing of cosmetic and pharmaceutical products.
The research makes human skin one of the first living organs created using bioprinting to be introduced in the marketplace, researchers said.
It replicates the natural structure of the skin, with a first external layer, the epidermis with its stratum corneum, which acts as protection against the external environment, together with another thicker, deeper layer, the dermis.
This last layer consists of fibroblasts that produce collagen, the protein that gives elasticity and mechanical strength to the skin.
The skin "can be transplanted to patients or used in business settings to test chemical products, cosmetics or pharmaceutical products in quantities and with timetables and prices that are compatible with these uses," said Jose Luis Jorcano, professor at Universidad Carlos III de Madrid (UC3M).
Bioinks are key to 3D bioprinting, researchers said. When creating skin, instead of cartridges and coloured inks, injectors with biological components are used.
"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 Juan Francisco del Canizo, from the Hospital General Universitario Gregorio Maranon in Spain.
The act of depositing these bioinks is controlled by a computer, which deposits them on a print bed in an orderly manner to then produce the skin.
The process for producing these tissues can be carried out in two ways: to produce allogeneic skin, from a stock of cells, done on a large scale, for industrial processes; and to create autologous skin, which is made case by case from the patient's own cells, for therapeutic use, such as in the treatment of severe burns.
"We use only human cells and components to produce skin that is bioactive and can generate its own human collagen, thereby avoiding the use of the animal collagen that is found in other methods," researchers said.
"This method of bioprinting allows skin to be generated in a standardised, automated way, and the process is less expensive than manual production," said Alfredo Brisac, CEO of BioDan Group, bioengineering firm in Spain.
The research was published in the journal Biofabrication.