There’s news about embryonic “master stem cells” for heart tissue, or embryonic stem cells that give rise to the 3 types of cells in the heart, which were found in mouse embryos.
I wonder how many of the articles will mention non-embryonic human cardiac precursor cells from amniotic cells (this month) and umbilical cord stem cells (reported in 2005, 2005, and this year) that have been used to produce heart valves in the lab?
Or that umbilical cord blood cells and the embryonic cells that are derived from them are less likely to be rejected than we thought in the past?
The animal research will be useful to find the markers or identifying genes of precursor cells in the human. They might lead us to the discovery of factors and conditions that will recruit and stimulate each patient’s stem cells in place. But they won’t treat anyone. As the article above about the embryonic stem cells explains, the local environment and stimulation are the determining factors that turn precusors in to functional tissues.
(Edited 11-24-06 for grammar.)