NIH is indifferent to adult stem cell research advances. Facts they choose to ignore

FOR IMMEDIATE RELEASE  August 28, 2000
Contact: Gene Tarne/Michelle Powers (703) 684-8352 (Do No Harm)

 NIH GUIDELINES MISLEADING ON ADULT STEM CELLS
NIH unaware or indifferent to adult stem cell research advances

In Guidelines issued 8/23/00 for Research Using Human Pluripotent Stem Cells, the National Institutes for Health (NIH) makes several misleading statements regarding the potential of adult stem cells for scientific and medical advancement. The facts on adult stem cell research undermine the NIH’s rationale for funding destructive human embryonic stem cell research:

NIH: “[S]tem cells for all cell and tissue types have not yet been found in the adult human. Significantly, cardiac stem cells or pancreatic islet stem cells have not been identified in adult humans” 

FACT: Neither have cultured embryonic stem cells been made to differentiate into all tissue types, including cardiac or pancreatic stem cells. However, adult stem cells for these tissues have been identified in mice, and adult pancreatic stem cells have been used to cure diabetes in mice (“Reversal of insulin-dependent diabetes using islets generated in vitro from pancreatic stem cells,” Nature Medicine 6, 278-282, March, 2000).  As with most biological discoveries, animal models have paved the way for clinical uses in humans and we should expect that these same adult stem cells are present in humans.  Reporting on this adult pancreatic stem cell research, theBritish Medical Journal (BMJ) says: “Early results suggests that ductal tissue taken from human cadavers can be grown in culture to form functioning islet cells,” which could lead to harvesting, stimulating and transplanting pancreatic tissue from diabetic patients themselves.  The BMJ reports: “This would not only avoid some of the risks associated with rejection of foreign tissue but could also potentially end the need for daily insulin injections.” (BMJ 320:736; 3/18/00). 

Moreover, there are numerous recent reports of adult stem cells being transformed from one tissue type to another (e.g., bone marrow to liver or nerve; nerve to blood), so it appears that adult stem cells have the capacity to form many more tissues than the one from which they are derived (e.g., “Liver from Bone Marrow in Humans,” Hepatology 32, 11-16, July, 2000; “Adult Bone Marrow Stromal Cells Differentiate into Neural Cells In Vitro,” Experimental Neurology 164, 247-256; “Turning Brain into Blood: a hematopoietic fate adopted by adult neural stem cells in vitro,” Science 283, 534-537, 1/22/00).  In this respect, adult stem cells are considered by some researchers (including NIH funded researchers) to be pluripotent, similar to embryonic stem cells, with the ability to form any tissue necessary (e.g., “Generalized Potential of Adult Neural Stem Cells,”Science 288, 1600-1663, 6/2/00;  Adult Rat and Human Bone Marrow Stromal Cells Differentiate Into Neurons,” Journal of Neuroscience Research 61:364-370 August, 2000). 

NIH: “[S]tem cells in adults are often present in only minute quantities, are difficult to isolate and purify, and their numbers may decrease with age…Any attempt to use stem cells from a patient’s own body for treatment would require that stem cells would first have to be isolated from the patient and then grown in culture in sufficient numbers to obtain adequate quantities for treatment.”

FACT: Research is showing these claims not to be true.  In March of this year, researchers in

Philadelphia identified the conditions to allow large-scale expansion of adult stem cells in culture, making these cells an almost unlimited resource.  The researchers achieved a billion-fold increase in a few weeks for bone marrow stem cells in culture. (“Rapid expansion of recycling stem cells in cultures of plastic-adherent cells from human bone marrow,” Proceedings of the National Academy of Sciences, 97, 3213-3218, 3/28/2000).  In mid-August, research funded by the NIH itself and the Christopher Reeve Paralysis Foundation found that adult human bone marrow stem cells can create a “virtually limitless supply” of nerve cells (“Christopher Reeve Paralysis Foundation Funds Breakthrough Research,” Press Release of the Christopher Reeve Paralysis Foundation, 8/14/00).  According to the published research results, the adult stem cells “grow rapidly in culture, precluding the need for immortalization, and differentiate into neurons exclusively with use of a simple protocol” (“Adult Rat and Human Bone Marrow Stromal Cells Differentiate Into Neurons,” Journal of Neuroscience Research 61:364-370, August 2000).

NIH: “[B]rain cells from adults that may be neural stem cells have been obtained only by removing a portion of  the brain of an adult with epilepsy, a complex and invasive procedure that carries the added risk of further neurological damage.”

FACT: While obtaining neural stem cells from the brain is a complex procedure, the NIH/Christopher Reeve Paralysis Foundation funded research demonstrates that adult bone marrow stem cells can form nerve cells, eliminating the need to isolate such cells from the patient’s brain: “The marrow cells are readily accessible, overcoming the risks of obtaining neural stem cells from the brain, and provide a renewable population.  Autologous transplantation overcomes the ethical and immunological concerns associated with the use of fetal tissue” (“Adult Rat and Human Bone Marrow Stromal Cells Differentiate Into Neurons,” Journal of Neuroscience Research 61:364-370 August, 2000).

In addition, studies with mice have shown that, given appropriate signals, neural stem cells do not need to be removed from the brain at all for growth.  Rather, they can be stimulated to regrow while still residing within the brain. The re-growth could take place even in regions of the adult mammalian brain that do not normally undergo new cell growth. The researchers report: “Our results indicate that neural replacement therapies for neurodegenerative diseases and CNS injury may be possible through manipulation of endogenous neural precursors in situ” (“Induction of neurogenesis in the neocortex of mice,” Nature 405, 951-955, 6/22/00).  Again, discoveries in animal models will almost certainly lead to applications in humans. 

NIH: “[I]n disorders that are caused by a genetic defect, the genetic error likely would be present in the patient’s stem cells, making cells from such a patient inappropriate for transplantation.”

FACT: But such transplantation is exactly what was done for three children in France, as reported in April of this year.  The infants, who had a genetic defect that caused severe immunodeficiency, had some of their own bone marrow cells removed.  The cells were cultured, the defective gene causing the immuno-deficieny replaced, and the children were then treated with their own stem cells.  This experiment using adult stem cells appears to be the first successful instance of a cure by human gene therapy (“Gene Therapy of Severe Combined Immunodeficiency (SCID)-X1 Disease,” Science 288, 669-672, 4/28/00). 

Moreover, correction of the genetic defect may not always be necessary to effect a cure with adult stem cells.  The British medical journal Lancet reports researchers treating systemic lupus (an incurable and sometimes fatal autoimmune disease) using the patients’ own bone marrow cells.  When transplanted back into the patients, the cells appeared to have overcome the defect in all patients and repaired organ damage previously considered permanent.  The scientists noted: “It is mysterious that the transplanted cells, which have the same genetic defect that made the patients’ immune cells go wrong in the first place, did not grow up to repeat the mistakes of their siblings” (“Treatment of severe systemic lupus erythematosus with high-dose chemotherapy and haemopoietic stem-cell transplantation: a phase I study,” Lancet 356, 701-707, August 2000).

Do No Harm: The Coalition of Americans for Research Ethics rejects the course of action taken by the National Institutes for Health to support destructive human embryonic stem cell research.  Instead, our government should promote adult stem cell research which protects the inviolability of individuals, rejects harming some for the potential benefit of others, and holds as much, if not more, promise of medical progress.  

For more information on adult stem cell progress, please visit our website at www.stemcellresearch.org