The question that remains is as follows: for what practical reason new cell sources should be explored? One possible reason is certainly the scientific curiosity to see if the reprogramming of a given cell type is possible and to find cellular characteristics that increase or decrease reprogramming efficiency, a prerequisite to understand pluripotency. Furthermore, it is of broad interest to find new possible cell sources for reprogramming with respect to availability and efficiency. Additionally, it is also advisable to adapt the method to the cell donors. For example, people with burned skin are not recommended for skin biopsies and patients who suffer from leukemia or immunodeficiency should not donate blood cells or have any kind of surgery. On the other hand, for diseases with a genetic background and a phenotype in certain cell types or organs, it can be reasonable to take especially those cells in culture which are affected.
