Stem Cells and Spinal Injury
Stem Cells and Spinal Injury
An Australian reader of this blog wanted to know more about stem cells in curing spinal injury and paralysis. So here’s some of what I’ve found.
In February 2005, the Swedish Karolinska Institutet issued a press release on a study of stem cells into rats who had sustained spinal cord injury. The researchers found that the stem cell injections improved the mobility of the rate beneath the site of the injury, but they had a greater sensitivity to pain above it: “The aggravated sensitivity to pain was thought to be the result of the fact that many stem cells developed into astrocytes, a kind of glial cell that encourages the growth of pain axons in the spinal cord by secreting substances that stimulate neuronal development.”
The researchers performed a follow-up study where they inserted a gene, neurogenin-2, into the stem cells while they were still in vitro. When these stem cells were injected into the site, not only did the adverse pain affect not appear but motor function and sensation below the site of the injury improved. Apparently the gene both inhibited the growth of pain-causing axons and increased the production of myelin sheathing around the damaged nerves.
However, this does not mean a human cure is in sight. A Reuters Health article on September 19, 2005 after the study in which mice with spinal injury had improved function (see Blog post “Neural Stem Cell Therapy Successful in Treating Spinal Cord Injury in Mice,” 9/20/05) included this statement:
For treating spinal cord injury, "there is hope, but we are a long way off," Dr. Brian J. Cummings from University of California, Irvine, told Reuters Health. "Our study improved function in mice with very controlled injuries. We did not cure these mice.”
Two other useful accounts of the study on mice can be found at ScienceAGoGo and National Geographic News. Some general information on spinal cord injury can be found at the Reeve-Irvine Research Center.
