Stem Cells for Spinal Cord Injury: Some Patients Have Long-Term Improvement
Thirty Percent of Patients Show Improved Functioning after Stem Cell Therapy
Philadelphia, Pa. (May 17, 2012) – One of the first long-term studies of stem cell treatment for spinal cord injury shows significant functional and other improvements in three out of ten patients, reports a study in the May issue of Neurosurgery, official journal of the Congress of Neurological Surgeons. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.
The results support the safety of mesenchymal stem cells (MSCs) derived from the patient’s own bone marrow, showing “continuous and gradual motor improvement” in at least some patients with disability caused by spinal cord injury. The lead author of the new study was Dr. Sang Ryong Jeon of University of Ulsan College of Medicine, Seoul, South Korea.
Evidence of Improved Function after MSC Treatment for Spinal Cord Injury
The researchers performed MSC transplantation in ten patients with permanent motor (movement) deficits or paralysis (paraplegia or quadriplegia) after spinal cord injury. Mesenchymal stem cells are a type of “multipotent” cell that can be cultured from adult bone marrow and induced to develop into many different types of cells.
The cultured MSCs were injected directly into the injured spinal cord and the surrounding (intradural) space. Additional cells were injected after another four and eight weeks. The results were assessed by measuring improvement in the patients’ ability to move their arms and hands and to perform key activities of daily living. Imaging scans and tests of muscle activity were performed as well.
During the first six months after MSC transplantation, six of the ten patients showed improvement in motor power of the arms and hands. Of these, three patients had gradual improvement in the ability to perform daily activities—for example, preparing meals and typing on a keyboard.
These three patients also showed significant changes on MRI scans of the spinal cord, including evidence of healing around the injured area of the spine. They also had improvement in electrophysiologic studies of muscle electrical activity.
No Long-Term Safety Problems of MSC Transplant
None of the ten patients had any permanent complications related to MSC transplantation. This helps to alleviate concerns that MSC injection could lead to later problems like the development of tumors or calcifications.
Previous studies have shown promising results with MSC transplantation in animals and humans with spinal cord injury. Mesenchymal cells have some important potential advantages for stem cell therapy, as they are a relatively easily accessible source of the patient’s own cells. The ten patients treated by Dr. Jeon and colleagues represent the first attempt at direct spinal injection of MSCs for the treatment of spinal cord injury in humans.
Following up on a previous study reporting initial improvement in six patients, the new paper describes continued improvement—including meaningful gains in the ability to perform everyday functional tasks—in three patients. Dr. Jeon and colleagues note that all three patients with progressive improvement had some “residual neurological function.” They write, “Therefore, MSC treatment is more likely to enhance the remaining neurological function rather than rengeneration.” They call for further studies to understand the mechanism of improvement after MSC treatment and to clarify which patients with spinal cord injury are most likely to benefit.