October 25, 2005 > Stem cells- a different view
Stem cells- a different view
by Vidya Pradhan
In July of this year, we carried a three-part series on stem cell research and how it created hope for a wide range of human disorders including many kinds of cancers, Parkinson's, diabetes etc. In response, one of our readers, Jill Pyles, wrote: "...I hope you will show a different point of view. Not everyone thinks that stem cell research is acceptable. The President is one. I am another. I myself did IVF and have a little baby now. It's not good to destroy embryos created by IVF. There is a group called Snowflakes that adopts embryos out. You could write about that. You could also write about umbilical cord stem cell storage. I hope you will continue to be "accurate, fair and honest" and show different sides of the stem cell issue....." This article is our attempt to do that.
To briefly recap, stem cells are primitive cells that can be developed into virtually any other kind of human cell, an ability called "pluripotency." Stem cell therapy relies on substituting diseased cells with healthy, functioning cells. While a common misconception is that all stem cells are derived from the embryo there are primarily two kinds of stem cells - embryonic stem cells, also called ESC's, and adult stem cells. Adult stem cells from the blood are used in bone marrow transplants for treating leukemia.
ESC's are derived from 5-6 day old embryos developed from eggs that have been fertilized in-vitro (in a laboratory). These embryos (also known as pre-embryos or blastocysts) are made up of about 150 cells of which about 30 cells make up the inner cell mass. This mass is then cultured in the laboratory to multiply into more cells. Over a period of time, the original 30 cells can yield millions of individual cells. These millions of undifferentiated cells create one stem cell line.
While embryonic stem cells show enormous promise because of their ability to be cultured in large quantities and their ability to be pluripotent, the process of cell extraction makes the embryo unviable. This makes the whole subject of embryonic stem cell research not just an ethical issue, but also an emotional one. For the person who suffers from Parkinsons's or Alzheimer's, it is the next frontier from which a cure may emerge. For a parent of an adopted child, it is violating the sanctity of life. For the scientist, it is a cluster of cells that might change the face of modern medicine.
In the United States, stem cell research faces strong opposition, because most cutting edge research happens with stem cells derived from the embryo. In May of this year, President George W. Bush showed his support for a program that encourages adoption of embryos remaining over from in-vitro fertilization techniques, a number that is estimated at around 400,000.
Leisa Brug Kline, spokesperson for Embryo Awareness Adoption, whose goal is to raise overall public awareness of the embryo adoption option nationwide, said that the program is funded through a grant from the United States Department of Health and Human Services. This funding is allocated annually through a proposal process that started in 2003.
One program, The Snowflakes Frozen Embryo Adoption Program, was the first agency to offer this unique way of adopting children. They are the "grandparents" of the program, which has successfully resulted in 91 babies born since 1998 with five more due by the end of this year.
The agency will match genetic parents (those giving their embryos up for adoption) with adopting parents either through an open or closed adoption process. The embryos are shipped to the doctor of the adopting parents and implanted into the woman just like traditional in-vitro fertilization (IVF) procedure. If the embryos survive in the womb, the woman goes through the pregnancy and gives birth just as if she had naturally conceived, said Kline.
The ethical dilemma surrounding embryonic stem cells has spurred research into other alternatives. Adult stem cells, also known as somatic cells, previously were once considered a poor source, because they were hard to find and did not lend themselves to undifferentiated multiplication. But new research has shown that they are present in more tissues of the body than previously thought.
Scientists from Harvard have also found a way to fuse existing embryonic cells with adult skin cells to create a hybrid cell that acts as a stem cell. While this cell fusion technique has the potential to someday eliminate the need to create and destroy embryos, they caution that the technique is at present, "very inefficient and deeply flawed" and should not deter embryonic stem cell research.
Another alternative to ESC's appears to be cells derived from umbilical cord blood. A team of Texas and British researchers says it has produced large amounts of embryonic-like stem cells from umbilical cord blood, potentially ending the ethical debate affecting stem-cell research. These new cells, called cord-blood-derived embryonic-like stem cells (CBE's)are not quite as primitive as embryonic stem cells; the more primitive the cell, the more it is likely to change into a new kind of cell. However, they offer more potential than adult stem cells such as those found in bone marrow. So far, CBE's have shown potential in creating tissue cells for the liver. Jersey Republican Rep. Chris Smith has teamed up with former NBA star Julius "Dr. J" Erving, calling for the passage of a bill that would increase stem cell research by using umbilical cord blood.
In the most recent sign of hope for opponents of embryonic stem cell research, scientists from Massachusetts-based Advanced Cell Technology succeeded in isolating embryonic cells from mice embryos without damaging the embryo.
While recognizing the enormous potential of stem cells to cure previously hopeless diseases, countries the world over are rushing to create regulations governing this ethically sensitive area of research. Research in stem cells is still at a very nascent, experimental stage. Reliable cures using stem cell therapy may be 5 to 10 years away. Only time will tell if they deliver on their promise.
Sources: National Institute of Health http://stemcells.nih.gov; www.newsday.com; The Washington Times www.washingtontimes.com; New Scientist www.newscientist.com; Nightlife Christian Adoptions www.nightlife.org; Production of stem cells with embryonic characteristics from human umbilical cord blood. McGuckin CP, Forraz N, Baradez MO, Navran S, Zhao J, Urban R, Tilton R, Denner L.; Harvard Scientists advance cell work. Article in Boston Globe. August 22, 2005; Stem cell research foundation. www.stemcellresearchfoundation.org; www.cancerbacup.org.uk; Hope over stem cell ethical fears www.bbc.co.uk October 17, 2005; www.whitehouse.gov/news/releases.