Guided Migration of Neural Stem Cells Derived from Human Embryonic Stem Cells by an Electric Field.

It is possible to transplant human embryonic stem cell-derived neurons into the brain of rodents and other animals to test potential treatments and replacement therapies for neurodegnerative diseases and brain damage. However, the implanted cells might not end up in the desired area, where they could best make an impact in treating the damage or replacing lost cells. Dr. Zhao's team studies a mild electrical pulse to guide cells to the area where they are needed. The tiny electrical probe acts rather like the "pied piper" and the cells follow it. The scientific term for this interesting system is "galvanotaxis". This paper reports, for the first time, that human neural stem cells that had been created under defined conditions from the embryonic stem cell line H9 also display this behavior. Associated videos show the cells follwing the electrical gradiaent toward the cathode, then when the electrical field is reversed, they flip over like a swimmer in a pool and move in the opposite direction. We are currently studying galvanotaxis in the brains of rodents transplanted with human hESC-derived neurons. It may seem far-fetched to think about electrodes in the brain, but this is a very weak pulse that does not damage surrounding tissue, and it is related to the now standard practice of deep brain stimulation for patients with Parkinson's disease. We hope to guide transplanted neurons and neural stem cells to the area of the brain that most needs repair, through this CIRM-funded research.