Stem cells are able to proliferate and differentiate into various tissues, but the resulting growth will be the age of the parent cells.  In short, old stem cells do not produce genuinely younger tissue—at least until now.  Researchers at the University of Toronto have shown that growing stem cells in cultures where growth factors are added and allowed to circulate through artificial scaffolding do seem to reverse their aging. One use of this could be in making “young” cardiac patches for old hearts.   MORE