“Our idea was to use a growth factor stimulant to increase the number of circulating stem cells from within the body’s bone marrow where they would have the potential to travel to the site of injury and begin repair, slowing down the progression of ALS,” says Cashman, who also holds the Canada Research Chair in Neurodegeneration and Protein Misfolding Diseases at UBC and is a member of the Brain Research Centre at UBC Hospital. “This pathway, if one day successful, may provide a new therapy that will avoid the ethical debate surrounding embryonic stem cells,” says Cashman.
Growth factors are proteins that can stimulate cell division. They occur naturally in the human body and can also be developed in a laboratory. Stem cells serve as a “repair system” in the human body and have the potential to develop and divide into many different cell types. “The project was complex because growth factors have the potential to activate the wrong cells in the brain and spinal cord, which could be harmful to ALS patients” says Cashman.
The researchers identified Granulocyte Colony Stimulating Factor (G-CSF) as the safest possible growth factor to use. They then conducted the pilot trial to establish safety and measure stem cell mobilization. “We were able to measure a prominent effect on stem cell mobilization and found no adverse effects in the patients,” said Cashman. “There have been many misgivings in using stem cell stimulators in ALS patients but now we know we can safely do this. This is an important first step in providing a new treatment for ALS.”