The first human embryonic stem cell treatment approved by the FDA for human testing has been shown to restore limb function in rats with neck spinal cord injuries – a finding that could expand the clinical trial to include people with cervical damage.

Results of the cervical study currently appear online in the journal Stem Cells. UCI scientist Hans Keirstead hopes the data will prompt the FDA to authorize clinical testing of the treatment in people with both types of spinal cord damage. About 52 percent of spinal cord injuries are cervical and 48 percent thoracic.

"People with cervical damage often have lost or impaired limb movement and bowel, bladder or sexual function, and currently there's no effective treatment. It's a challenging existence," said Keirstead. "What our therapy did to injured rodents is phenomenal. If we see even a fraction of that benefit in humans, it will be nothing short of a home run."

A week after test rats with 100 percent walking ability suffered neck spinal cord injuries, some received the stem cell treatment. The walking ability of those that didn't degraded to 38 percent. Treated rats' ability, however, was restored to 97 percent.

UCI's therapy utilizes human embryonic stem cells destined to become spinal cord cells called oligodendrocytes. These are the building blocks of myelin, the biological insulation for nerve fibers that's critical to proper functioning of the central nervous system. When myelin is stripped away through injury or disease, paralysis can occur.

Citation: Jason Sharp, Jennifer Frame, Monica Siegenthaler, Gabriel Nistor, Hans S. Keirstead
'Human embryonic Stem Cell-Derived Oligodendrocyte Progenitor Cell Transplants Improve Recovery after Cervical Spinal Cord Injury' Stem Cells Online, doi: 10.1002/stem.245