Posts Tagged ‘embryonic’

Embryonic and Induced Pluripotent Stem Cells Have Genetic Problems

Friday, January 7th, 2011

You know the saying, “there is no free lunch”? Well, several recent studies have rained on the parade of the embryonic stem cells and IPS crowd. A recent piece in the LA times quoting a paper published this week was more percipitation. The problem is that these cell lines have inherent genetic problems. This means that the cells don’t have normal genes, which raises the specter of unintended consequences when these cells are used for therapy (the biggest being cancer). The reason should be clear by now. Embryonic stem cells (or likely even adult stem cells) that are “immortalized” (artificially tricked into growing forever so that they can be mass produced like an antibiotic) pick up these genetic abnormalities because these cells were never designed by nature to have the DNA repair mechanisms that would allow them to be grown for these great lengths of time. For example, everyday, dividing cells in your body pick up back pieces of DNA or errors. We have enzymes that help repair the damage and a secondary line of defense (called the immune system) to yank the malfunctioning cells out of circulation. However, embryonic (or even adult stem cells) were never designed with the mechanisms to be grown for thousands of generations. An embryo is conceived, it grows bigger, and eventually a baby with adult stem cells is born. Nowhere in there was the embryo designed to grow embryonic stem cells for years for the purposes of satisfying a human need for mass produced biologic tissue. How about IPS cells? For those of you who are unaware, IPS means induced pluripotency, which is a fancy way of saying that a normal adult cell is turned into a cell that resembles an embryonic stem cell. Now since this doesn’t even happen in nature, the process of tricking a cell to revert back to the properties of a stem cell is bound to have issues (which many IPS researchers have been very honest about from the start). Again, since normal adult cells aren’t built to divide forever like IPS cells, the same discussion above applies. If you’re seeing a trend here, you’re not the only one. In both instances, it’s our need to create cells that can be mass manufactured to satisfy a business model that creates the problem. How about adult stem cells like those used in the Regenexx procedure family? Adult stem cells are built to do what we’re asking them to do. They help repair tissue and then either differentiate into the bricks and mortar of the repair or they orchestrate the construction job and then disappear from the scene. Growing adult stem cells for short periods (like in the Regenexx-C procedure), still keeps the cells within the parameters of what happens in the body. Studies have shown no significant genetic abnormalities when adult stem cells are grown for short periods and more interestingly, when they are grown very long periods (months and months) and do pick up genetic abnormalities, they don’t form cancers, they just don’t work anymore. Our complications tracking data has also shown that using these short-term cultured stem  cells in people poses less risks than the surgical procedures they help many patients avoid. This is consistent with the findings of others showing robust safety for cultured adult stem cells from bone marrow.

In summary, you can’t teach an old dog new tricks (I think that’s my third really bad turn of phrase). Trying to mass produce cells isn’t a good idea with our current state of knowledge. A better idea is using the patient’s own adult stem cells, which is the “customized” medicine long sought by physicians. While the business model may not be as good, it’s sure a heck of a lot safer for the patient.

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Adult Stem Research is Much Farther Ahead than Embryonic Stem Cell Research

Tuesday, August 3rd, 2010

Adult stem cells are much farther ahead in research and clinical applications than embryonic stem cells, an AP writer reports. While embryonic stem cells have been the darling of the media for years and adult stem cells have been the red headed stepchild, this major press coverage is a great advance in notifying the public of this discrepancy.  The bottom line, adult stem cells are being used in early clinical and research work to heal cartilage, bones, multiple sclerosis, heart attacks, diabetes, and other diseases.  This begs the obvious question, do we need embryonic stem cells?

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Induced Pluripotent Stem (IPS) Cells Show Problems

Sunday, February 14th, 2010

In a recent study, adult skin cells that were turned into embryonic like stem cells showed problems with advanced aging IPS cells are created from normal adult cells, usually by exposing them to some chemicals or inserting new genes.  If you know a basic amount about stem cell science, this story has to fall into the “duh” category.  Adult cells are not made to be immortalized (faked out so that they can be grown forever).  The only immortalized cells we encounter on a day to day basis are cancer cells.  So until we understand all there is to know about how a human cell works at a genetic machinery level (maybe 20-50 years from now?), trying to trick skin cells into becoming immortal stem cells is like juggling with hand grenades, it’s possible, just not smart.  Since these adult cells tricked into thinking they are stem cells at some level still know they are normal adult skin cells, they age like normal adult skin cells.  As I have posted before, there is no logical reason we are considering embryonic and IPS cells for drug candidates, as both have severe downsides compared to the patent’s own adult pluipotent stem cells (like the mesenchymal stem cells we use or other adult stem cell types).  In fact, I can think of only one reason why one would consider using these stem cell types at this early juncture, big pharma.  The only big advantage these cells have (other than the rare cases where the patient;s own cells might not work) would be that they can be grown in bio reactors,  placed in vials, and sold as drugs.  Since the patent’s own adult stem cells were built for repair and maintenance, other than the problems with business plan, they would be the best candidate for safe stem cell therapy now.  This is consistent with the adult stem cell safety study we just published.

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Embryonic vs. Adult Stem Cells

Thursday, May 7th, 2009
Embryonic vs Adult Stem Cell Research

Embryonic vs Adult Stem Cell Research

We’ve all heard about embryonic stem cells (ESC’s).  They have been in the news and the focus of controversy for a decade.  We’ve seen far less media coverage of  adult stem cells.  Adult stem cells (ASC’s) are found in everyone’s body and they are capable of repairing a host of tissues.  In fact, the research on adult cell lines has surpassed embryonic.  Above is the result of a search I did yesterday in the National Library of Medicine, looking at all embryonic stem cell published papers vs. the total on all adult stem cell lines.  As you can see, for every one ESC paper, there were at least two ASC papers.  In addition, the research on ASC’s is vastly more mature, focusing on animal models of tissue healing, dosing, early human cases, medication interaction with cells, possible complications, etc…  The ESC research is more test tube and review articles on what might be possible someday.  Looking in specific categories, I found the following:

· Cartilage Repair: 230 articles on embryonic vs. 1,113 for just one adult stem cell line (mesenchymal stem cells)

· Myocardial Infarction: 186 for embryonic stem cells vs. 341 for adult mesenchymal stem cells, 69 for endothelial progenitor cells

· Wound Healing: 114 for embryonic stem cells vs. 330 for adult mesenchymal stem cells, 565 for adult epithelial stem cells

For a more detailed analysis, take a look at the American Stem Cell Therapy Assocition (ASCTA) white paper on adult stem cells vs. embronic stem cell research.    Summary?  Adult stem cell research is much farther ahead.  In addition, as I have posted on before, if the cells are autologous (from the same patient), they also have a much lower risk profile.  While one day embryonic cells may rule the day, for now, adult stem cells are beating the pants off ESC’s in practical research.

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