Combinations of four different genes were transferred into the skin cells by a virus. The skin cells (called induced pluripotent stem [iPS] cells) had characteristics common to embryonic stem cells, including similar shape, cell surface identifiers, and telomerase (chromosome lengthening) activity.2 The iPS cells were able to become multiple cell types including neural, cardiac, cartilage, and others.3
This is exciting news, as it presents an alternative to embryonic stem cell usage and is another example of how adult stem cells are extremely versatile. Another advantage would be the ability to use a person’s own skin cells for formation of the iPS cells, thus eliminating rejection upon transplantation. At the same time, caution is in order, as the iPS were made using a virus, which would likely not be approved by the FDA for use in humans (other delivery methods will likely be evaluated). Another possible problem is that like ESCs, the iPS may exhibit genetic instability, which could lead to tumor formation.
You can read more about the pros and cons of ESCs and adult stem cells in Stem Cells.
Footnotes
- Alan Boyle, “Skin Cells Made to Mimic Stem Cells,” msnbc.com, November 20, 2007.
- Junying Yu et al., “Induced Pluripotent Stem Cell Lines Derived from Human Somatic Cells,” Sciencexpress, November 20, 2007.
- Kazutoshi Takahashi et al., “Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors,” Cell 131 (2007):1–12.