*Endogenous Stem Cells  are your own adult stem cells already present in your body NOT from a donor.  

Stimulating endogenous stem cells: The adult brain has neural stem cells in areas like the hippocampus, that generate new neurons which can influence these cells to increase and assimilate into the affected areas.

*Asymmetric cell division with younger cells

*Artificial cells

Synthetic cells can be used to allow growth factors to tissue development of damaged parts for desired results not using live cells