Cell therapy, particularly with stem cells, has created great interest as a 
solution to the fact that there are limited treatments for postischemic heart 
disease and none that can regenerate damaged heart cells to strengthen cardiac 
performance. From the first efforts with myoblasts to recent clinical trials 
with bone marrow-derived stem cells, early reports of cell therapy suggest 
improvement in cardiac performance as well as other clinical end points. Based 
on these exciting but tentative results, other stem cell types are being 
explored for their particular advantages as a source of adult stem cells. 
Autologous adipose-derived stem cells are multilinear and can be obtained 
relatively easily in large quantities from patients; cardiac-derived stem cells 
are highly appropriate for engraftment in their natural niche, the heart. Human 
umbilical cord blood cells are potentially forever young and allogenic adult 
mesenchymal stem cells appear not to evoke the graft versus host reaction. Human 
embryonic stem cells are effective and can be scaled up for supply purposes. The 
recent discovery of induced pluripotentcy in human adult stem cells, with only 
three transcription factor genes, opens a whole new approach to making 
autologous human pluripotent stem cells from skin or other available tissues. 
Despite the excitement, stem cells may have to be genetically modified with heme 
oxygenase, Akt or other genes to survive transplantation in a hypoxic 
environment. Homing factors and hormones secreted from transplanted stem cells 
may be more important than cells if they provide the necessary stimulus to 
trigger cardiac regrowth to replace scar tissue. As we await results from larger 
and more prolonged clinical trials, the science of stem cell therapy in cardiac 
disease keeps progressing.