Unfortunately, available treatments for neurological injuries are limited in scope as it stands now. Most therapies are confined to supportive or palliative measures aimed at managing the symptoms of the conditions rather than the underlying causes. Recovery is therefore, typically incomplete and often results in significant and permanent disabilities. These limitations have fueled research into possible treatments that could address the underlying causes rather than only the symptoms.
Stem cells to treat brain injuries
There is tremendous interest—and strides being made—in developing stem cell therapies as potential treatments to repair damage, regain function and improve quality of life in patients with neurological disorders. Such therapies represents a potential sea-change in treatments and results.
Drs. Joanne Kurtzberg and Jessica M. Sun review the potential use of umbilical cord blood (CB) as a source of stem cells for such therapies and some of the debilitating brain injuries that may be effectively treated with cord blood and cord tissue stem cells. Each of the conditions covered in their article, have trials underway illustrating the wide array of prevalent, devastating conditions that umbilical cord blood and cord tissue may be able to treat in the future.[i]
What’s so special about cord blood stem cells?
All of these features make CB an attractive source of cells for cellular therapies and regenerative medicine:
- Stem Cell Characteristics:
- Rich in highly proliferative stem and progenitor cells that are can readily reach developing organs
- Compared to stem cells found in adult bone marrow, they are less mature and therefore have greater potential to multiply
- CB-derived cells have been separated out into numerous cell types throughout the body including neural cells
- Availability: there are more than 130 million births per year worldwide, so there is ample opportunity to collect CB units for regenerative purposes which can be cryopreserved for decades for future use
- Safety Profile: CB can be collected non-invasively without risk to the mother or infant especially compared to bone marrow stem cells: also they are less likely to transmit infections than bone marrow stem cells
- Noncontroversial: historically, was discarded as medical waste
Umbilical cord tissue is also readily available for harvest at the time of delivery. Mesenchymal stromal cells (MSCs) have been directly isolated from cord tissue and studied in animal models. These tissues are currently being studied in early-phase clinical trials for arthritis, spinal cord injury, Alzheimer’s disease and autism.
Genetic brain disorders in children
Children born with certain inherited metabolic diseases lack a critical enzyme necessary for the production and maintenance of myelin. The lack of myelin can result in progressive neurological deterioration. Affected babies may appear normal at birth but develop symptoms in the first months to years of life ultimately resulting in death in childhood. When patients with these diseases received a cord blood transplant early in the course of their disease, the cord blood stem cells were able to serve as a constant source of enzyme replacement. The natural progression of the disease was slowed or ceased—extending the patient’s life for decades—and neurologic functioning greatly improved.
The use of cord blood is currently under investigation in clinical trials for a variety of ischemic-related conditions (i.e. when the brain doesn’t get enough oxygen) including neonatal hypoxic ischemic encephalopathy, cerebral palsy and stroke. Clinical studies evaluating the use of CB in children with cerebral palsy are ongoing. Preliminary studies report greater improvements in cognitive and select motor functions in children who received intravenous CB infusions.
With stem cell therapy emerging as potential treatment for other neurological conditions, the question of whether it might have a role in the treatment of autism has also been raised. The hypothesis has been generated that CB infusion may aid in the restoration of faulty neural connections in children with autism. Autologous CB treatment (when a child receives their own cord blood) in children with autism is currently under investigation in several countries and clinical trials are underway at Duke University in North Carolina.
Stem cell therapies to treat neurodegenerative diseases have been studied most extensively in Parkinson’s disease. In patients with Parkinson’s, certain types of neurons are deteriorating. Therefore, treatment of Parkinson’s is focused on cell replacement and studies indicate that CB has potential as a source of stem cells for cellular replacement in Parkinson’s disease.
Trials done with mice treated with CB MSCs (see above) show decreased cognitive impairment and an extended lifespan in Alzheimer’s disease. ALS (also known as Lou Gehrig’s Disease) is another condition that may be responsive to cellular therapy. CB has been investigated in a mouse model of ALS and delayed the onset of disease and extended survival by 20-25%. CB stem cells were detected throughout the brain and spinal cord but concentrated in the ventral horn gray matter of the spinal cord, an area known to be affected by ALS.
Neurological injuries are typically associated with permanent and life-long disabilities, hefty expenses and a lack of therapeutic options. Until now, treatments, while providing relief from symptoms, have not been able to make a long lasting impact on the root cause of such conditions. Cellular therapies particularly those that use cord blood stem cells, have great potential to significantly advance the treatment of patients with acquired and genetic brain diseases.
Kurtzberg, Joanne, Sun, Jessica M. Cord Blood for Brain Injury. Cytotherapy
, International Society for Cellular Therapy, 24 February, 2015.