The often vaunted promise of stem cell therapy recently received another feather in its cap when Chinese researchers announced that lab mice who were treated with embryonic stem cells showed a reversal of the damage from Alzheimer’s disease.
The news contradicts previous theories on stem cell’s viability in treating the disease, which held that Alzheimer’s ability to affect a wide variety of neurons and biological processes would limit the effectiveness of stem cell treatments.
Professor Jing Naihe led the study, which was published in Stem Cell Reports. Prior to transplanting the cells into the brains of the experimental mice, they were first triggered to transform into neuron cells by Jing’s team.
After implantation, immune system responses in the mice killed off nearly 60% of the new neurons, with the remainder being used to repair the damaged brain areas. It was so effective that two months after the stem cell application, the treated mice performed comparably to normal mice when performing cognitive tests.
Jing spoke on the future prospects of the treatment, “We used human embryonic stem cells because this method will eventually be used on humans. If the human neurons can get a footing and grow in the brain of a mouse, the chance is high the effect will be even better on a human host.”
Fears that the cells might turn cancerous have so far been unfounded, with the treated mice showing no signs of tumors or other mutations over the seven year observation period. Still, Jing says that the treatment is not ready for use in humans, “Mice are still very different from humans, so the results on mice do not guarantee the same success on human patients. Our next step is to test the method on primates… It will probably be a long time before clinical trials can be carried out on human volunteers.”