A team of doctors in Germany and scientists in Italy were able to help a boy from Syria with a genetic disorder that left him with untreatable wounds covering 80 percent of his body.

The 7-year-old fled with his family from Syria to Germany in 2013, and by the time he started to receive treatment at University Children’s Hospital, Ruhr University Bochum, he had lost 80 percent of his skin. He has a disease called junctional epidermolysis bullosa, caused by a mutation of the LAMB3 gene, which produces the protein that makes the top layer of skin connect to deeper layers underneath. The condition made his skin fragile and quick to blister, and he only had his epidermis still intact on his head and a patch of his left leg. By the time doctors reached out to scientists in Italy, asking if they could grow replacement skin for the young patient, they knew he was running out of time, with morphine the only thing helping with the pain.

The scientists had regenerated healthy skin in a lab before, but never for as tall an order as this. They took epidermal cells from an area of his skin that did not have blisters, and genetically modified it in the lab, using a virus to correct the LAMB3 defect. The scientists then grew colonies of cells with corrected genes into sheets of genetically modified skin, and over two months, grafted the skin to the patient. The grafts grew together, and self-renewed, to the delight of the boy’s medical team.