by Derek Doroski, Adult Stem Cell Researcher at Georgia Institute of Technology
Many people have no idea that embryonic stem cells (ESCs) are not the only kind of stem cells. The alternatives to ESCs include adult stem cells (ASCs), fetal stem cells (ESCs, from umbilical cord, amniotic fluid, or placenta – not to be confused with fetal tissue or cells obtained through abortion), and induced pluripotent stem cells (iPSCs). Unlike ESCs, none of these other stem cell types require destruction of a human being.
In general, stem cells possess two properties; cell division (one cell becomes two) and potency (ability to change into a different kind of cell). The two main advantages of ESCs are their immortality (cell division that is unlimited) and pluripotency (high potency that allows change into any cell type in the body). No other stem cell types possess immortality. However, fetal stem cells and iPSCs both seem to possess the same pluripotency as ESCs. In addition, while any individual ASC is not pluripotent, there is an ASC for almost any cell type so they could be considered pluripotent as a population. In short, the most commonly touted advantage of ESCs – their pluripotency – is not really an advantage over other stem cell types.
Two problems with embryonic stem cells include their immunogenicity (rejection by patient’s immune system) and their tendency to form potentially deadly tumors. The other stem cell types all have an advantage in this category. None of the alternative stem cells types (ASCs, FSCs, and iPSCs) have the immunogenicity problem and only iPSCs share the tendency to form tumors. I know a prominent bioengineering professor that asked his class whether they thought adult or embryonic stem cells would be more useful in the long term. He has no qualms with ESC research, but his answer was that it was going to be ASCs providing long term cures because they did not have the immunogenicity issue.
Despite what you might assume from the media coverage, ESCs have yet to provide a single treatment. Meanwhile, ASCs and FSCs have over 73 treatments to their name. One example is Jaki Rabon. She is a young woman that was the passenger in an SUV accident. After being thrown from the car she fractured her spine at T12 making her a paraplegic. She flew to Portugal to receive a treatment that involved ASCs from her own nose. She now has feeling in her hips and legs. With a walker she is able to walk independently. The long term picture seems just as good for ESC alternatives. I did a recent scan of the headlines of <http://www.stemcellresearchnews.com/> to see what a third party site had to report. 6 stories about ASCs, FSCs, and iPSCs. Just 1 about ESCs.
A search on <www.clinicaltrials.gov> reveals over 1000 clinical trials involving non-embryonic stem cells. In comparison, the first clinical trial for ESCs just made the news recently and it already seems to be going badly. ASC and FSC research is providing treatments now. In the long term ASCs, FSCs, and iPSCs all seem to have better potential as stem cell specific news stories and clinical trials attest. For more information go to <http://www.stemcellresearch.org> and <http://www.stemcellresearchfacts.com>.
Derek Doroski is a PhD Candidate in bioengineering at Georgia Institute of Technology in Atlanta, GA. He has had the opportunity to see the success adult stem cells are having while researching them as a doctoral student. Derek is also involved with the Students for Life group where he works to inform others about the benefits of adult stem cells.