Our skin – not only the biggest organ of the human body, but also an extremely delicate and injury-prone one. On average it has a thickness of just a few millimetres. Now it is the first organ that can be artificially reproduced – for some years even in a fully automated process.
So-called “tissue engineering” refers to the farming of human tissue, mostly in the area of the skin. Until now, artificial skin, which is used for transplants after serious accidents or burns or for compatibility tests in the cosmetics or pharmaceutical industries, could only be produced manually and with extreme difficulty. In this way, usually no more than 2,000 pieces of skin just square centimetres in size could be produced per month. The “Factory for human skin” in the BioPoLiS bio-production laboratory belonging to the Frauenhofer IPA in Stuttgart can currently produce up to 5,000 thumbnail-sized skin models per month.
The concept sounds simple, yet the manufacturing process is complicated. A human skin sample is cut into little pieces and the individual skin cells are extracted. The isolated cells are sown in special cell culture flasks and multiplied over several days in an incubator at 37°C. The multiplied cells can be combined with a gel matrix to form a three-dimensional, multi-layer construct. After just three weeks the artificial skin has grown in size and is ready for safety tests.
The facility for the production of artificial skin is a showcase project of bio-production, the symbiosis of biology and automation technology. Particular attention was paid to creating a continuous process chain. More than 100 Festo components are installed in the facility. Their range extends from compressed air preparation to sensors, cylinders and electrical axes, as well as servo and stepper motors, through to fast-switching valves. These components are used to screw on tubes, automatically open and close airlock doors, hold the covers for the disks into which the cells are inserted, monitor the compressed air and move other parts like needles and mould cavities.
Not only skin is a sought-after organ for test systems. The technology is expected to be developed further over the next few years to allow other tissues such as cornea from the human eye to be produced automatically. One of the aims of this technology in future is to manufacture customer-specific models – for example to make the therapy for tumours even more effective. Should the research into the artificial production of long-lasting tissue using blood supply systems progress further, the automated production of a body's own transplants is even conceivable.