Appendix K. 
Adult Stem Cells 
DAVID A. PRENTICE, PH.D. 
Professor of Life Sciences at Indiana State University, Terre 
Haute, Indiana 
Within just a few years, the possibility that the human body 
contains cells that can repair and regenerate damaged and diseased 
tissue has gone from an unlikely proposition to a virtual certainty. 
Adult stem cells have been isolated from numerous adult tissues, 
umbilical cord, and other non-embryonic sources, and have 
demonstrated a surprising ability for transformation into other tissue 
and cell types and for repair of damaged tissues. This paper will 
examine the published literature regarding the identity of adult stem 
cells and possible mechanisms for their observed differentiation into 
tissue types other than their tissue of origin. Reported data from 
both human and animal studies ■will be presented on the various 
tissue sources of adult stem cells and the differentiation and repair 
abilities for each source, especially ■with regards to current and 
potential therapeutic treatments. 
Adult stem cells have received intense scrutiny over the past 
few years due to surprising discoveries regarding heretofore 
unknown abilities to form multiple cell and tissue t'ypes, as well as 
the discovery of such cells in an increasing number of tissues. The 
term "adult stem cell" is somewhat of a misnomer, because the cells 
are present even in infants and similar cells exist in umbilical cord 
and placenta. More accurate terms have been proposed, such as 
tissue stem cells, somatic stem cells, or post-natal stem cells. 
However, because of common usage this review will continue to use 
the term adult stem cell. 
This paper "will review the literature related to adult stem 
cells, including current and potential clinical applications (with 
apologies to the many who are not cited, due to the exponential 
increase in papers regarding adult stem cells and the limitations of 
this review.) The focus will be on human adult stem cells, but will 
also include results from animal studies which bear on the potential 
of adult stem cells to be used therapeutically for patients. 
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