Over a decade ago the polarizing topic of stem cell therapy came to the forefront of the media and stirred the sociopolitical undercurrents of the country. The policies in question involved the use of embryonic stem cells for the purpose of research and eventually medical treatment of some of the most arduous diseases.
Fast-forward to 2013, currently the debate regarding the usage of stem cells has been somewhat diffused by increased usage of autologous (cells or tissues obtained from the same individual) adult stem cells. The usage of adult stem cells is less controversial because it does not require the destruction of an embryo. The primary roles of adult stem cells in a living organism are to maintain and repair the tissue in which they are found. Adult stem cell treatments have been successfully used for more than 50 years to treat leukemia and related bone/blood cancers through bone marrow transplants. (See timeline below for the history of stem cells)
New Legislation in Texas
In April 2012, the Texas Medical Board passed new rules regarding the use of adult stem cell therapy. The new rules allow doctors to bypass FDA approval after they meet specific requirements set forth by the Texas Medical Board, which is also responsible for the licensing and disciplining of doctors.
How will the new rules affect you and me? The new rules allow doctors to perform stem cell procedures as long as they are done for research and receive approval from an institutional review board selected by the governor of Texas. The rules also require that patients sign informed consent forms.
Texas Gov. Rick Perry has been a long-time advocate for passing new legislation. Perry has reported relief from very painful back problems after receiving injections of his own stem cells isolated from adipose (fat) tissue. Before treatment he found it difficult to walk up and down the stairs, but after two separate treatments (one was an injection of his own adult stem cells during surgery to fuse vertebrae in the governor’s spine, and the other was intravenously) he was able to run up and down the stairs.
This post will not try to address the multifaceted layers of government policy on treatment with stem cells, although they are very important and play an emotional part in the lives of many faced with pain and degeneration, but I hope to lay a foundation to understand the nature of adult stem cells and how they can be used for medical breakthroughs.
Need to Know Basics of Adult Stem Cells
Stem cells are the foundation for every organ, tissue and cell in the human body. Stem cells may be able to repair or replace damaged tissue, thereby reversing diseases and injuries such as cancer, diabetes, cardiovascular disease and blood diseases, just to name a few. Adult Stem Cells are non-embryonic cells that by definition, are unspecialized or undifferentiated cells that not only retain their ability to divide mitotically while still maintaining their undifferentiated state but also, given the right conditions, have the ability to differentiate into different types of cells including cells of different germ-origin – an ability referred to as transdifferentiation or plasticity (the quality of being easily shaped or molded).
Image via docstoc.com
Birdsong and Hope for the Future
We don’t commonly think about how amazing the logistics are in the development of birdsong, but one Argentinean man with a life-long passion for the study of birdsong revolutionized the understanding of stem cells and neurogenesis (the ability to produce new viable nervous tissue).
Fernando Nottebohm has long been fascinated with the similarities between human vocalizations and birdsong and in the 1960’s he began conducting research that revealed that male canaries experienced new neuronal growth in the song nuclei region of the brain prior to mating periods. Surprisingly enough these findings were staunchly rejected, since the implication of similar neurogenesis in humans usurped long held beliefs about the brain’s inability to regenerate cells.
Nottebohm used a radio-actively labeled marker (thymidine) to show new neuronal cell growth. Thymidine is an enzyme that has a key function in new DNA synthesis and cell division. After injection, any new cells produced in the birdbrains would express radioactivity. Nottebohm and his team discovered large numbers of radioactive cells, many of which were nerve cells – new nerve cells were being made at an astonishing rate. The team wondered, could this regeneration be directed to heal damaged brain tissue?
Finally in 1998, inspired by Nottebohm’s work, Fred Gage and his team (using a technique very similar to Nottebohm’s radio-active marker) at the Salk Institute found that adult human brains were also able to make new nerve cells.
The Field of Stem Cell Research was Opened Wide
Suddenly, scientists could see the potential for using newly dividing brain cells to treat neurodegenerative disorders, such as Parkinson’s, Alzheimer’s, Stroke, Amyotrophic Lateral Sclerosis, Multiple Sclerosis, etc. If these stem cells could be delivered to the damaged part of the brain, maybe they would divide and specialize, replenishing the damaged tissue and restoring people to good health.
The History of Stem Cell Research
| 1956 | First successful bone marrow transplant between a related donor and recipient is performed by Dr E. Donnall Thomas in New York. The patient, who has leukemia, is given radiotherapy and then treated with healthy bone marrow from an identical twin. |
| 1960 | Researchers discover bone marrow contains at least two kinds of stem cells — blood or hematopoietic stem cells that form all the types of blood cells in the body and stromal stem cells that form bone, cartilage, fat, and connective tissue. |
| 1960 | First research report to indicate that the brain may generate new nerve cells is published, but not widely accepted. Studies done by Fernando Nottebohm on birdbrain and song nuclei led to discovery of neural stem cells. |
| 1968 | British scientist Robert Edwards and his student, Barry Bavister, became the first to fertilize a human egg in the test tube. This is the beginning of in vitro fertilisation (IVF) technologies. |
| 1968 | First bone marrow transplant for non-cancer treatment. Dr Robert Good uses a bone marrow transplant to treat an eight year old boy with severe combined immunodeficiency syndrome (SCID). The donor is an HLA-matched sister. |
| 1973 | First bone marrow transplant between unrelated patients. A five-year old patient in New York with SCID is treated with multiple infusions of bone marrow from a donor in Denmark. |
| 1978 | The first IVF baby is born in England. |
| 1978 | Blood stem cells are discovered in human umbilical cord blood. |
| 1981 | Mouse embryonic stem cells are derived for the first time from the inner cell mass of a mouse blastocyst and grown in vitro. |
| 1984-1998 | Pluripotent stem cells are isolated. When exposed to retinoic acid, these cells differentiate into neuron-like cells and other cell types. |
| 1989 | Preimplantation genetic diagnosis (PGD) is developed — a method where a single stem cell can be removed from an IVF embryo and tested for inherited diseases. |
| 1990 | Bone marrow donor program initiated. |
| 1990 | Dr Thomas receives the Nobel Prize in Physiology or Medicine for his pioneering work on bone marrow transplants. |
| 1995 | Scientists at the University of Wisconsin derive the first embryonic stem cells from non-human primates. |
| 1998 |
Stem cells from IVF Scientists at the University of Wisconsin, led by James Thompson, isolate and grow the first stem cells from human embryos. The embryos used in these studies were created by IVF. |
| 1999 | Researchers discover that stem cells can be made to differentiate into different cell types. |
| 2001 | President George W. Bush permits federal funding of embryonic stem cell research, but only on the 64 existing stem cell lines. |
| 2004 | Researchers in South Korea claim to be the first to clone a human embryo and then harvest the stem cells for research. The research is later found to have been fabricated. |
| 2004 | California becomes the first state in the USA to provide its own fund for embryonic stem cell research. |
| 2005 | George W. Bush’s restrictions on embryonic stem cell research are loosened. |
References:
Filip S, Mokrý J, Hruška I (2003) Adult stem cells and their importance in cell therapy. Folia Biol.(Prague) 49: 9-14.
http://www.biotechlearn.org.nz/themes/biotech_therapies/timeline_for_stem_cell_research
http://www.ipscell.com/2012/04/the-real-but-oft-ignored-dangers-of-adult-stem-cell-treatments/
http://www.nature.com/news/stem-cells-in-texas-cowboy-culture-1.12404
http://news.bbc.co.uk/2/hi/science/nature/4544777.stm
http://www.nytimes.com/2012/04/14/us/new-rules-on-adult-stem-cells-approved-in-texas.html?_r=0
http://www.tellmeaboutstemcells.org/stem-cell-basics/the-difference.php
http://www.texastribune.org/2012/04/13/medical-board-adopts-controversial-stem-cell-rules/
Birdbrain Breathrough. In Smithonian: Science and Nature [World Wide Web]. Kiester, Edwin Jr., and Kiester, William Smithsonian magazine, June 2002 [cited Sunday, April 14, 2013] Available at http://www.smithsonianmag.com/science-nature/birdbrain.html?c=y&page=2
What are adult stem cells?. In Stem Cell Information [World Wide Web site]. Bethesda, MD: National Institutes of Health, U.S. Department of Health and Human Services, 2012 [cited Wednesday, April 10, 2013] Available at <http://stemcells.nih.gov/info/basics/pages/basics4.aspx>
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