For the first time, people with broken spines have recovered feeling in previously paralysed areas after receiving injections of neural stem cells.
Three people with paralysis received injections of 20 million neural stem cells directly into the injured region of their spinal cord.
The cells, acquired from donated fetal brain tissue, were injected between four and eight months after the injuries happened. The patients also received a temporary course of immunosuppressive drugs to limit rejection of the cells.
None of the three felt any sensation below their nipples before the treatment. Six months after therapy, two of them had sensations of touch and heat between their chest and belly button.
The third patient has not seen any change.
"The fact we've seen responses to light touch, heat and electrical impulses so far down in two of the patients is very unexpected," says Stephen Huhn of StemCells, the company in Newark, California, developing and testing the treatment.
"They're really close to normal in those areas now in their sensitivity," he adds.