Parkinson's disease is an incurable disorder of the nervous system that has affected millions of patients over many years. Now, a breakthrough treatment for this disease may become a reality. In October this year, a surgery was performed at Kyoto University to transplant nerve cells derived from iPS cells, which have the potential to differentiate into various cell types. For this episode, Dr. Jun Takahashi of Kyoto University's Center for iPS Cell Research and Application (CiRA), who developed this treatment, will make a guest appearance in the studio to talk about how he prepared for the groundbreaking cell transplant, and how the surgery was performed. Have they overcome safety issues such as tumor formation?