Amyotrophic Lateral Sclerosis (ALS) is a devastating disease that progressively destroys nerve cells, called motor neurons, in the brain and the spinal cord, eventually causing paralysis and death. Baseball great Lou Gehrig first brought national attention to the disease in 1939 when he retired from baseball after being diagnosed with ALS. He died two years later, but ALS is still commonly referred to as “Lou Gehrig's Disease.”
People who have ALS steadily lose their ability to control muscle movement. Patients in the later stages become totally paralyzed, although their minds are often unaffected. The average life expectancy of a person with ALS is two to five years from time of diagnosis. Many ALS sufferers die within a few years due to failure of the nerve cells that control breathing.
The cause of ALS is unknown and there is currently no cure. One FDA-approved drug, Rilutek, helps slow the progression of ALS, but no existing treatment halts or reverses the disease.
Human and Social Costs
An estimated 30,000 Americans, including hundreds of Kansans, suffer from ALS. Every day, an average of 15 more people are diagnosed with ALS – more than 5,600 people per year.
The financial cost to families of persons with ALS is extremely high. In advanced stages of the disease, caring for an ALS patient can cost up to $200,000 a year, imposing an enormous financial and emotional toll on affected families.
The Potential for Stem Cell Cures
More than 50 years of research on adult stem cells, taken from adult tissues, has produced such lifesaving treatments as bone marrow transplants for leukemia patients. And, adult stem cells are likely to provide additional cures for some diseases in the years ahead.
However, the new frontier in stem cell research involves early, or “embryonic,” stem cells (ES cells). Unlike adult stem cells, ES cells have the potential to turn into and regenerate any type of cell or tissue in the human body. As a result, ES cells could provide cures for many currently incurable or common diseases and injuries that cannot be cured with adult stem cells, or more effective treatments than adult stem cells may provide.
Recent studies indicate that ES cells can generate healthy new nerve cells. Thus, they could someday be transplanted into a patient’s body to treat or cure diseases like ALS, by generating healthy cells to replace diseased and damaged cells.
There are two basic sources of ES cells for such potential therapies. One source is the leftover embryos at fertility clinics that would otherwise be discarded and destroyed. ES cells can also be produced with Somatic Cell Nuclear Transfer (SCNT), a process that uses a patient’s own cells and an unfertilized human egg to make ES cells. SCNT has the added advantage of producing ES cells that will automatically match the patient’s genetic makeup. As a result, SCNT avoids the need to find a genetically matching donor and the problem of immune system rejection, two limitations associated with donated adult and ES cells.
SCNT has also given medical researchers a method of growing cells that have the defects associated with a disease in a laboratory setting. This use of SCNT provides new ways to study how a disease like ALS progresses at the cellular level and to test the effectiveness of new drugs or other treatments that may cure or slow the progress of the disease.
Another option being studied is the use of ES cells to develop astrocytes, special cells that nourish and support brain and spinal nerve cells. These astrocytes could, in turn, help the patient’s own body regenerate nerve cells and reduce symptoms associated with ALS.
Recent animal studies by medical researchers at Johns Hopkins University found that ES cell transplants restored movement to rats paralyzed with an ALS-like syndrome. Those studies also indicated that ES cells may not only replace damaged cells, they may also act as rejuvenating “pumps,” secreting growth factors that revitalize damaged neural micro-environments.
Studies published this year by scientists at Dalhousie University in Halifax demonstrate that ES cells in experimental animals can be directed to differentiate into cells with the properties of functional motor neurons, a finding that may lead to ES cell therapy for motor neuron damage like that seen in ALS.
The consensus of the medical and patient community is that all types of stem cell research should be pursued in the effort to find cures for diseases like ALS, and that ES cells can play an important role in this effort.
That’s why ES cell research is strongly supported by the overwhelming majority of medical researchers, medical organizations like the American Medical Association, and disease and patient advocacy groups like the ALS Association, ALS Therapy Development Foundation, Project ALS and Jack Orchard ALS Foundation.
Links to More Information:
"Stem Cell Treatment Helps Rats Paralyzed With ALS-Like Syndrome Walk Again."
Jack Orchard ALS Foundation
The ALS Association - Midwest
The ALS Therapy Development Foundation
“Scientists explore new directions in ALS research.”
UW School of Medicine
“Stem cells reduce brain damage.”
Harvard University Gazette
“Research Shows Therapeutic Cloning Technique May Work in Mice.”
“Focus on ALS: The Facts and Fiction of Cloning”
“In vitro differentiation of transplantable neural precursors from human ES cells.”
“Stem cell research keeps hopes afloat.”
Robert Packard Center for ALS Research at Johns Hopkins
“Human neural stem cell-derived cholinergic neurons innervate muscle in motoneuron deficient adult rats.”
Department of Neuroscience and Cell Biology, University of Texas Medical Branch
“Functional properties of motoneurons derived from mouse embryonic stem cells.”
Department of Anatomy and Neurobiology, Dalhousie University
“Rebuilding the Nervous System with Stem Cells.”
The National Institutes of Health