The genetic disorder epidermolysis bullosa is the stuff of nightmares. The epidermis contains the cells that form our body's boundary with the outside world; in epidermolysis bullosa, they lose their ability to hold on to the cells underneath them. Small scratches that healthy people wouldn't notice cause the skin to blister off, leaving these patients prone to infection. The constant inflammation makes cancer more likely. More than 40 percent of those afflicted don't even survive to adolescence.
Now, for the first time ever, researchers have restored functioning skin to a young epidermolysis bullosa patient. Their method? His lost skin was entirely replaced using stem cells that had been genetically engineered to replace the inherited defect. The basic outline of the work, published today in Nature, would have sounded like a work of science-fiction less than two decades ago.
The work was possible because of years of basic research and technology development. To begin with, we have a good handle on the genes involved in epidermolysis bullosa and how the proteins they encode work. The junction between the cells of the epidermis and underlying dermis contains a bed of proteins called the extracellular matrix. The cells on either side have specialized proteins that allow them to latch on to the extracellular matrix. Epidermolysis bullosa is caused by mutations that damage any of a number of genes that encode components of the extracellular matrix or the protein that latches on to them. Because we knew all of this, it's relatively easy to identify the damaged gene when doctors encounter a patient with epidermolysis bullosa.