Facts & Myths About Stem Cells
Adult stem cells are partially specialized cells that can turn into a limited number of body cells and tissues. For example, blood-forming adult stem cells in bone marrow can turn into some types of blood-related cells. Other adult stem cells with limited differentiation possibilities include but are not limited to: umbilical cord blood cells; mesenchymal stem cells, adipose-derived stem cells and fetal stem cells. In contrast, ESCs are “pluripotent,” meaning that they are totally unspecialized cells that have the potential to turn into and regenerate any type of cell or tissue in the human body. As a result, ESC could provide cures for diseases and injuries that cannot be cured with adult stem cells, or could provide more effective treatments than adult stem cells.
Not at all. ESC have much greater capacity to differentiate and can form all the different tissues of the body. Cells derived from fetal tissue are restricted to produce cells related to their tissue of origin. For example, cells from the fetal nervous system are commonly used to develop tissue cultures of the several types of cells found in the nervous system.
Medical researchers believe that ESCs could provide cures for many currently incurable or common diseases and injuries, including diabetes, Parkinson’s, MS, cancer, heart disease, ALS, sickle cell disease, spinal cord injury and dozens of other debilitating medical conditions. In fact, it is estimated that over 70 different diseases and injuries could benefit from ESC research. Currently, there are clinical; trials in the United States examining the use of ESC-derived cells for treatment of spinal cord injury, Type I diabetes and blindness resulting from macular degeneration. Click here for more information.
It is estimated that the various medical conditions that could someday be cured or treated with ESCs currently afflict hundreds of thousands of Nebraskans and millions of other Americans – including a child, parent or grandparent in over half of all families. In fact, almost everyone has a family member or friends who could benefit from ESC research.
Most diseases and injuries involve defective or damaged cells and tissues. ESCs, or more specialized cells made from ESCs, could be transplanted into a patient’s body, where they could regenerate or repair a patient’s damaged cells or tissues. For example, ongoing clinical trials are testing if ES-derived cells could: be used to cure Type I Diabetes by generating healthy new insulin-producing pancreatic cells or, Ongoing pre-clinical research aims to use ESC-derived cells to regenerate healthy nerve and brain cells, potentially providing cures for diseases like Parkinson’s disease, ALS and Huntington’s disease as well as for strokes. ESC-derived cells could also be used to treat various types of severe injuries, such as serious burns, and traumatic bone/muscle injuries as well as recovery from significant surgical interventions (transplants and reconstructions). Many of these potentials are of special interest to the military and are often grouped as “warfighter injuries”.
Yes. Embryonic stem cell research using cells derived from excess embryos of families with known genetic defects has given medical researchers a method of growing cells that carry the defects associated with a disease in a laboratory setting. This provides new ways to study how a disease progresses at the cellular level and to test the effectiveness of new drugs or other treatments that may cure or slow the progress of the disease.
ESC research has led to a better understanding of these remarkable cells and promoted rapid advances in many related areas. Indeed, analysis of some of the distinctive molecular underpinnings that endow ESC with their unique ability to differentiate into so many cell types or retain their “stem cell” characteristics led Dr. Shinya Yamanaka, in 2007, to develop a remarkable system in which he could “induce” normal skin cells to behave much like ESC. These cells became known as induced pluripotent stem cells (iPSC) and they have many of the same characteristics of ESC but can be genetically identical to the donor of the skin sample and are not in any way derived from an embryo. There is great hope that these cells may be able to replace ESC in experimental and clinical applications but, for now, ESC still are the gold standard for true stem cells.
Because of the huge potential it offers to save lives and reduce human suffering, ESC research is strongly supported by the overwhelming majority of medical researchers, including more than 60 Nobel Prize winning scientists; by many major medical organizations, like the American Medical Association; by dozens of disease foundations and patient groups, like the American Diabetes Association, Christopher Reeve Paralysis Foundation, Parkinson’s Action Network, Juvenile Diabetes Research Foundation and National Coalition for Cancer Research (NCCR); and by leading patient advocates, like Michael J. Fox and Nancy Reagan. It remains a fundamental tool that guides a great deal of basic and clinical research.
Yes. All types of stem cells (ESC, Adult SC, iPSC, fetal SC, Umbilical cord SC, adipose SC, etc.) have their own special characteristics and potential uses for curing different diseases and injuries. That’s why the overwhelming majority of medical experts, medical organizations and patient advocacy groups – including the Nebraska Coalition for Lifesaving Cures – agree that all types of stem cell research should be pursued in the effort to find lifesaving cures.
Yes, but the only federal limitations on stem cell research and cures are on the use of federal funds. Current federal policy limits federal funding for ESC research to stem cell lines derived from fertility clinic embryos no longer wanted for reproductive purposes. These ESC lines were derived without the use of federal funds and following strict regulations for human use consent and the origin of the cells. There are currently over 350 eligible cell lines listed in the NIH registry. In the private sector, there are many more cell lines being developed and made available for numerous research projects. In Nebraska, state resources may not be used to create or destroy an embryo but research may be conducted with federally approved cell lines (Reference; The “Compromise” Legislative Bill 606 of 2008).
ESC research is being actively pursued at medical research facilities in states throughout the country. Some states – such as California, Maryland, Massachusetts, New Jersey, Connecticut and Illinois – recently passed legislation to support and encourage ESC research. Researchers in many other countries that have advanced medical research facilities are also actively pursuing ESC research, such as the United Kingdom, Canada, South Korea, Singapore, Japan, Sweden, India, Australia, Israel and Spain.
Better described as somatic cell nuclear transfer (SCNT), therapeutic cloning is the transplanting of a patient’s DNA into an unfertilized egg in order to grow stem cells that could cure devastating diseases. The promise of SCNT was that the patient’s body would accept rather than reject these cells after transplantation. Therapeutic cloning produces stem cells, not babies. No sperm is used in this procedure. And the cells are not transplanted into a womb. SCNT aims to treat or cure patients by creating tailor-made, genetically identical cells that their bodies won’t reject. In other words, SCNT could allow patients to be cured using cells containing their own DNA. Because of advances with iPSC and the technical difficulties with the SCNT process, SCNT research has been relatively quiet over the past several years. Also in LB 606, SCNT research is not permitted using state resources in Nebraska.
Reproductive cloning is the use of cloning technology to create a child. Nebraska Coalition for Lifesaving Cures opposes reproductive cloning. Patient advocacy groups and leading scientists, and a majority of Americans agree that human reproductive cloning should not be allowed. Also in LB 606, SCNT research is not permitted using state resources in Nebraska.
No. Considering the great genetic diversity of the human population, there are a relatively small number of National Institute of Health approved ESC lines available to government-supported researchers and not enough to proceed at full pace with extensive research into treatments and cures. Scientists need more cell lines to fulfill the promise of embryonic stem cell research. The availability of new cell lines produced by the iPSC process has also been a boon to stem cell researchers. Further advances with other approaches will hopefully add to the spectrum of available cells used in research and potentially therapy for a wide variety of difficult diseases and conditions.
Every medical procedure has risks. A goal of clinical trials is to determine if the possible benefit of a treatment outweighs the risks. A possible risk of some stem cell treatments may be the development of tumors or cancers. For example, when cells are grown in culture (a process called expansion), the cells may lose the normal mechanisms that control growth or may lose the ability to specialize into the cell types you need. Also, embryonic stem cells will need to be directed into more mature cell types or they may form tumors called teratomas. Other possible risks include infection, tissue rejection, complications arising from the medical procedure itself and many unforeseen risks. One of the intents of clinical research is to limit risks while maximizing benefits.
A bone marrow transplant, also called a hematopoietic stem cell transplant, is a medical procedure used to treat conditions of the blood such as leukemia, sickle cell anemia, or some metabolic or genetic conditions. It relies on the hematopoietic (blood) stem cells that are present in the bone marrow and blood that are the precursors to all circulating blood cells. Doctors have been transferring the stem cells by bone marrow transplant for more than 40 years. Advanced techniques for collecting or “harvesting” similar stem cells from the blood are now used. Cord blood, like bone marrow, is stored as a source of blood stem cells and is used as an alternative to bone marrow in some transplantation procedures.
Other stem cell applications are the use of skin progenitor cells for burns, and the use of limbal stem cells, which reside in the cornea, for injury of the cornea. Despite intensive research, no therapies are available yet using embryonic stem cells, although three clinical trials, to treat spinal cord injury, type I diabetes and a certain type of blindness respectively are currently underway. Initial reports from these clinical trials have not shown and “adverse events” and appear promising.
However, with the exception of the treatments discussed here, the use of “stem cell therapies” to treat many other devastating diseases and has not been shown to be safe or effective. Indeed, the proliferation in the US and abroad, of “Stem Cell Clinics” that offer treatments for everything from impotence to autism has become a significant problem. Patients are advised to avoid such clinics. The International Society for Stem Cell Research has valuable guidance in that regard.