The researchers at Osiris Therapeutics in Baltimore report in the journal Science that they isolated a single cell, called a mesenchymal stem cell, and then grew it into a colony of more than a million cells that could be induced to produce bone, cartilage or fat. It may be that such cells can eventually be used for therapy, and that would be quite exciting. Thomson and UW colleagues were the first to isolate and grow human embryonic master cells, from which all other types of cells and tissue arise. The research, announced last November, came after 17 years of work in which Thomson's team also was the first to isolate and grow similar cells in primates. Scientists in Israel participated in that effort.
Stem cells are the body's building blocks.
Research involving ones that come only from embryos, such as pluripotent stem cells, has drawn opposition. That's why the mesenchymal cells used by Osiris, which are produced in adults, are a key development in the rapidly expanding field of stem cell research. However, only pluripotent stem cells from embryos are thought to be capable of growing into any tissue in the body. The mesenchymal stem cells are the parent lines for bone, cartilage, fat, tendon and muscle. Still, the Osiris work helps move stem cell research from the laboratory toward the clinic, said David J. Anderson, a Howard Hughes Medical Institute stem cell researcher at the California Institute of Technology.