It can affect the lining of the mouth and esophagus as well as the skin, and makes activities that many children take for granted, such as eating, painful.
The trial was the first to use bone marrow stem cells to treat something other than diseased or damaged marrow, said Tolar, associate professor of pediatric transplantation at the University of Minnesota.
Between 2007 and 2009, the team of researchers from Japan, Britain and the United States led by Wagner and Tolar treated six children with RDEB, aged 15 months to 14 years, with chemotherapy and a bone marrow stem cell transplant.
Follow-ups of the children 30 and 130 days later showed wounds were healing more quickly in all the children and four out of six had reduced the amount of dressings they had to use on their skin sores.
All the children had higher levels of collagen 7, the protein missing in children with RDEB which is responsible for keeping layers of skin "glued" together and to the body.
Five of the six children were alive 799 days after transplantation; one died at 183 days.
Wagner and Tolar are still measuring the progress each child is making after treatment, including monitoring improvements in health as well as in the strength of the recipient’s skin after transplant.
"What we now know is that after this treatment, healthy donor cells reside in the skin, collagen 7 consistently increases over time and the skin gradually becomes more resistant to blister formation," said Wagner.
"This discovery expands the scope of marrow transplantation and serves as an example of the power of stem cells in the treatment of disease," he said.
The findings of the study, published in the New England Journal of Medicine, "suggest that the infusion of bone marrow from a healthy donor can ameliorate RDEB in humans, as has previously been shown in the mouse model of the disorder."
There is currently no treatment for RDEB, and in some countries, euthanasia has been considered for newborns with the severest forms of the illness, according to a release from the University of Minnesota.
Children with EB who do not die of infection early in life often do not live beyond their 20s or 30s because they develop an aggressive form of skin cancer.
Since 2007, Wagner and Tolar have treated 10 children with the most aggressive forms of EB with transplanted bone marrow containing the healing stem cells.
All of the children have responded to the therapy, to varying degrees.