text: One of the most studied methods is to use the patients own cells to generate a new organ, ex-vivo Specifically, researchers have chosen to focus on adult stem cells, or somatic stem cells, for the generation of new organ cells to create organs. There has been success in the production and use of some organs. The first stem-cell based organ, a tracheal graft, was transplanted successfully in 2008. The method involves obtaining a donor organ, removing the cells and MHC antigens from the donor organ, and colonizing it with stem cells obtained from the patient. This method does not create an entire organ from stem cells, and it still requires a donor to provide the decellularized graft. However, the first surgery done with this method was successful and the patient has shown no signs of rejection since. The current debate with this method is whether the decellularized graft was only used to provide the shape of the organ, or whether it provided benefits from it being a donor graft. Current research is being done to find ways to use adult stem cells for neo-organs without using decellularized donor organs for structural support.