.jpg)
Features
Moving Past Controversy in Stem Cell Technology
by Ashlie Rodriguez
From the ritualistic chants of medicine men to the painful procedure of bloodletting, it has taken centuries for humans to discover the causes of and cures for their ailments.
Only within the last 200 years has science been able to shed light on the validity of medical practices. In the mid-1800s, the germ theory of disease was formally accepted, followed by Joseph Lister’s revolutionary discovery of antiseptics, forever changing the landscape of medical know-how.
The 20th century brought about even more advances in medicine. Through the unearthing of vaccines and antibiotics, thousands of lives were saved from illness and infection. It was during this period that for the first time in history, the discovery of human genetics explained the mysterious force behind sickness.
Now, in this high tech generation, scientists are discovering cutting edge technology that promises the world advancements in health and medicine beyond our wildest imagination. The most prominent of these breakthroughs—and ironically, the most controversial—is embryonic stem cell technology.
A Closer Look at Embryonic Stem Cells
Extracting embryonic stem cells begins four to five days after an egg has been fertilized. At this point in development, the fertilized egg, or embryo, is known as a blastocyst made of 50-150 cells. The cells of a blastocyst are extremely versatile and regenerative, allowing them to replenish dying cells, such as those in cancer patients, or generate new tissues and reform damaged muscles. These lines are very adaptable and have the potential to develop into an estimated 200 cell types in the body, providing for a wide variety of treatments.
Yet when embryonic stem cell research is mentioned, eyebrows immediately raise, lips pucker, and tensions flare. Although there is potential for stem cell lines to treat Parkinson’s disease, Alzheimer’s, Multiple Sclerosis and even spinal cord injuries, the concept is an undeniably controversial one.
For many religious and anti-abortion groups, ethicists and scientists, embryonic stem cells conjure up images of the industrialization of fertilized eggs, cloned babies, and the devaluation of human life. These groups believe that life starts at the moment sperm fertilizes an egg, leading to the interpretation that the destruction of an embryo is tantamount to the murder of a developing human.
Scientists, a number of religious organizations, political leaders and countless others who have been diagnosed with irreversible ailments such as heart disease, leukemia and diabetes, view embryonic stem cells as the opportunity for hope, healing, and a second chance at life. Proponents of the research regard week-old embryos as only a cluster of cells that do not contain any human characteristics. They do not believe using the cells of an embryo amounts to destroying a human life.
While both counterparts are valid in their beliefs, incessant butting of heads cannot bring about progress. Yet, it is only progress that can usher our world into the next chrysalis of health and longevity.
History shows us that in order for human evolution to flourish, rigid belief systems must be loosened, traditional mindsets must expand and higher knowledge, accepted. From the idea of germs to the conception of genes, the realization of progress is a gradual climb. By stubbornly holding onto personal agendas, by refusing to meet in the middle and move forward, our high tech generation only hinders development for those to follow.
Stem cell research is a life saving, revolutionary technology which must be allowed to move forward. The question is: How can scientists bring about the health benefits stem cell research promises while adhering to ethical principles?
President Obama may have found a solution to this ethical dilemma by pioneering a compromise between adversaries and proponents of embryonic stem cell research. In July, Obama fulfilled his promise to ease federal restrictions on stem cell research—but only on ethical grounds.
Researchers now have access to the much sought after federal funds for embryonic stem cell lines, but only if they can ensure that lines were derived through ethical procedures. Research-ers are now required to keep embryos left over from in vitro fertilization procedures, ensure donors are made fully aware of their rights and choices, and depend on absolute volunteerism in the donations of embryos. Donors cannot receive payment in any form.
Obama’s effort to reconcile the two opposing groups is a step in the right direction, yet it is only one of many. Right now, researchers are confronting the stem cell stalemate head-on and working to expand the mediums of stem cell line generation.
Stem Cells from the Scientific Perspective
Ricardo M. Zayas, PhD, Assistant Professor of Biology at San Diego State University, is the principal investigator of a laboratory devoted to studying the molecular and cellular mechanisms underlying tissue regeneration. Freshwater planarians, which are non-parasitic flatworms, are the subjects of his research, as they possess high regenerative capabilities and provide an excellent opportunity to explore molecular mechanisms that regulate maintenance, proliferation and differentiation of stem cells in vivo.
Zayas believes that embryonic stem cell research is vital to moving forward in the field. “I think it is necessary to continue to study pluripotent stem cells, which means capable of giving rise to all the cell types in the body,” Zayas explained. “Until we know more about all the various stem cell types, it would be premature to discontinue studies using embryonic stem cell lines.”
In his scientific opinion, many of the ethical dilemmas raised by pro-life groups are not valid and only hinder research.
“The development of stem cell technology was the result of decades of challenging, careful experimentation carried out by numerous researchers,” Zayas pointed out. “I think the argument of embryonic stem cell technology as ‘bad science’ is a misrepresentation. A different question [in terms of] going forward is how embryonic stem cells will be generated in the future.”
Zayas may be onto something. In fact, new developments in the field have brought to light numerous ways of harvesting cells without using human embryos, allowing the life-saving potential of this technology to flourish without engaging in ethical conflicts. Of these developments, it is adult stem cells that have proven to be most successful.
The Potential of Adult Stem Cells
Adult stem cells, existing to replace dying cells, are found in the tissues, blood, and bone marrow of human beings. Increasing amounts of evidence show that adult stem cells are able to generate and replenish dying cells, but they are less capable than embryonic cells of differentiating into the vast cell types. Yet researchers are not deterred by these limitations. Instead, many have conducted numerous studies on adult stem cell lines and have found their treatment to hold much potential.
Northwestern University researcher Richard Burt, MD and fellow researchers have conducted approximately 60 studies, finding adult stem cell treatment to have curative effects on autoimmune diseases such as rheumatoid arthritis, Multiple Sclerosis, lupus, and Crohn’s disease.
Dr. Burt’s article entitled, “Clinical Applications of Blood-Derived and Marrow-Derived Stem Cells for Nonmalignant Diseases,” published in the Journal of the American Medical Association February 27, 2008, caught the attention of lawmakers in March 2008, who subsequently invited him, along with select patients, to speak on Capitol Hill. Of those invited, the story of Barry Goudy intrigued me the most.
Diagnosed with Multiple Sclerosis in 1995, Barry Goudy underwent constant hospital visits and tried myriad medicines, but all to no avail. Goudy constantly fell out of remission, forcing him to undergo more treatments and lose his grasp on life. Speaking before a Washington D.C. audience, Goudy recalled becoming immune to the medicine and having to increase doses, causing him deleterious effects such as weight gain, mood swings, and changes in personality.
In 2001, he was referred to Dr. Burt at Northwestern Memorial Hospital in Chicago. After being accepted into Dr. Burt’s experimental adult stem cell study in 2003, Goudy received an adult stem cell transplant. Four months later, Goudy went back to work symptom-free. Relating his story in 2008 on Capitol Hill, Goudy remained symptom-free and believed that adult stem cells had cured him of MS.
While successful, researchers are still unsure of adult stem cells. According to Zayas, since adult stem cells are not as versatile and harder to replicate, embryonic stem cells remain at the forefront of the budding technology.
“Adult stem cells are quite different from embryonic stem cells because they are not pluripotent,” Zayas noted. “In addition, adult stem cells are difficult to isolate in great numbers and expand in the laboratory. There are many potential advantages to developing therapies using adult stem cells, but it is not necessarily the case that this type of stem cell will replace research on embryonic-like stem cells.”
Although there is a great capacity for adult stem cells, the technology still has its disadvantages.
“For example,” Zayas said, “if tissues were derived from adult stem cells, they may be less likely to be rejected by a patient after transplantation, a major hurdle during organ replacement.”
According to a PBS “Nova” interview with Harvard virologist Dr. Ann Kiessling on www.pbs.org, media reports generally mention only two ways to produce human embryonic stem cells. Both techniques—the first using spare embryos from fertility clinics, the second involving cloning—are fraught with controversy. Yet the site discusses a possible third technique, parthenogenesis, capable of producing embryonic stem cells without running into ethical dilemmas.
Parthenogenesis: A Conceivable Alternative?
Parthenogenesis is defined as the spontaneous activation of an egg in the womb, without fertilization. Upon activation, the egg begins to divide, resembling an embryo at the early stage of development in which stem cells could be derived, according to Kiessling.
This technique side-steps many ethical concerns because a spontaneously activated egg in the womb has no ability to develop into a human being. And instead of relying on spare embryos from fertility clinics, a woman would be able to use her own eggs for her own stem cells, which seems more appropriate, in Kiessling’s opinion.
Although the technique has not been tested on human subjects, it has had success in animal lines of stem cells, encouraging the scientific community to invest considerable research into its progress.
According to Zayas, embryonic stem cell lines derived by parthenogenesis provide another viable alternative to generating pluripotent stem cells.
“However,” Zayas observed, “creating embryos by parthenogenesis can lead cells to be genetically unstable. Further study is necessary before we can fully appreciate the viability of this approach to generate stem cell lines.”
In addition, parthenogenesis cannot be used with men or post-menopausal women. Yet, if the research is allowed to move forward, the possibility of creating a bank of parthenogenetically derived stem cells could benefit an entire spectrum of patients.
“Only through rigorous yet cautious research will we be able to unveil the possibilities of this fascinating technology,” Zayas concluded.
While research in this field is a massive undertaking, it is worth the time and effort. As an alternative to fertility clinic embryos, parthenogenesis is interceding a compromise between those for and against embryonic stem cell therapy.
Regardless of whether you choose to support embryonic, adult or parthenogenesis stem cell research, it is the technology itself that needs to be advanced. For now, concerned citizens can press political leaders to vote in favor of stem cell research and to support our president’s efforts to establish compromise between ideologically opposing groups. It is time to usher in this stem cell technology with open minds. We can help our generation move past controversy through the willingness to fund, through persistence within the civilian and scientific community, and mainly, through the unified eagerness to improve the health of millions worldwide.
To learn more about Professor Ricardo M. Zayas’ research, visit www.bio.sdsu.edu/faculty/zayas/index.html. Zayas can be contacted for further information at rzayas@sciences.sdsu.edu or 619.594.2698. Ashlie Rodriguez is a freelance journalist whose passion is investigative political journalism. For more information, please visit www.ashlierodriguez.wordpress.com.