Adult stems cells (ASCs) are unipotent and multipotent tissue stem cells that are established in late fetal development and reside in post-natal tissues thereafter. Some ASCs are pre-disposed for in vitro conversion to induced pluripotent stem cells (iPSCs). Until now, ASCs have been difficult to propogate in vitro, due to inherent asymmetic cell division kinetics. The stem cell population does not expand, while the daughter cells committed to differentiation expand and form tissue specfic cell types that are often committed to a non-dividing state. Thus, unless the self-renewing population of stem cells can be maintained, it is not possible to maintain a consistent culture of many tissue specific cells. SACK Technology makes this possible.