Stem Cell Research:
What Does It Mean for Scleroderma?
By Carolyn Weller,
R.N. and Elaine Furst, R.N., B.S.N., M.A. (originally published
in "Scleroderma Voice," 2001 Issue #3)
 |
| Carolyn
Weller, R.N. |
Editor's note:
You can skip directly to the subheads that interest you, by
clicking on these links:
President rules
on embryonic stem cell
—New York Times
Parents freeze
umbilical cord blood for stem cell use in the future
—Seattle Post-Intelligencer
Stem cell research
might help cure Alzheimer's, Parkinson's and diabetes
—Newsweek
Whew! What has
been going on over the past few months? The headlines above
come from leading newspapers and magazines. The Internet also
has many articles and web pages devoted to the stem cell controversy.
The stem cell issue
involves elements of ethical, religious, and scientific thought
near and dear to each of us in some way. It can be very confusing
to patients and families affected by scleroderma, as well
as those of us who are involved with scleroderma support,
awareness, and research funding.
The stem cell research
controversy is a good example of how science, government,
and ethical concerns can overlap.
Celebrities such
as Michael J. Fox, who has Parkinson's, and Mary Tyler Moore,
who has diabetes, both made news when they testified before
Congress, adding to the number of stories on TV.
Because we've heard
some confusion among our own members, this article will try
to bring some light to the stem cell debate raging in Congress
and the media, and show how it relates to people affected
by scleroderma.
What
exactly is a stem cell?
Let's start by
explaining what an embryonic stem cell is. Immediately
upon fertilization a human egg begins to divide. One cell
becomes two, two cells become four, four cells become eight,
and so on.
After several cycles
of cell division, these cells begin to form a hollow sphere.
This sphere is called a blastocyst. This blastocyst consists
of two layers. The outermost layer of the blastocyst will
eventually develop into the placenta and other supporting
tissues that will support the fetus.
The inside layer
is a hollow sphere that contains a cluster of unique cells.
These cells will go on to form many different types of tissues.
It is these cells, which contain the potential to develop
in many different directions, that are referred to as the
stem cells.
Is
there more than one kind of stem cell?
Yes, there are
two main types of stem cells: the embryonic stem cells described
above, and stem cells that can be isolated from adult tissues.
Both types can be used for research, but many researchers
prefer to work with embryonic stem cells, because they are
easier to isolate and reproduce faster.
1.
Embryonic stem cells
The embryonic stem
cells that have been used for research were isolated from
frozen embryos, donated by infertile couples that no longer
require them for pregnancy purposes.
Embryonic stem
cells have the potential to help researchers in many ways.
For instance, they could help unlock the mystery of human
development at the cellular level-including what occurs during
cell division that causes birth defects and cancer.
Many researchers
believe they can be helpful in developing new drug therapies
for a variety of diseases. For example, it could be useful
to study the efficacy and safety of a drug at the cellular
level before beginning studies with animals and humans.
One particularly
exciting aspect of stem cell research is that scientists have
been able to stimulate stem cells to specialize and develop
into a variety of specific tissue types. This opens the possibility
of a renewable source of replacement cells and tissue to treat
many different diseases and conditions. Specialized heart
cells encouraged to grow in a lab setting could be injected
into a diseased heart, and ideally these new cells would work
to heal the heart by continuing to grow new, healthy cells.
Other diseases, conditions, and disabilities that could potentially
be treated with stem cells include Parkinson's and Alzheimer's
diseases, spinal cord injury, stroke, bums, diabetes, osteoarthritis,
and rheumatoid arthritis. According to the National Institutes
of Health (NIH), "There is almost no realm of medicine
that might not be touched by this innovation" (Stem
Cells: A Primer, National Institutes of Health, May 2000).
2.
Adult stem cells
Adult stem cells
also show promise. For example, stem cells have been isolated
in the hair follicles of adult mammals, and in theory could
become the specialized cells that would generate new hair
follicles, epidermis, and sebaceous glands. This development
could improve the results of skin grafts for burn patients,
help us understand the origins of some skin cancers, and be
used to treat hair loss and excess body hair.
Stem cells have
also been isolated in the bone marrow of adult rats. Scientists
then altered the cells' environment, transforming them into
nerve cells. These cells were injected into the brains of
rats, where they took up residence and formed connections
with other nerve cells. They are reported to have survived
within the brain for months without any adverse effects. Scientists
are hopeful that similar procedures could be used to repair
damaged areas of the brain.
Stem cells have
also been isolated in the blood, and in a lab setting have
been used to produce liver cells. This line of research could
significantly impact our ability to produce organs and tissues
for transplants. If the necessary tissues could be produced
from cells taken from the patient, it might be possible to
avoid rejection complications.
As noted above,
there are some drawbacks to using adult stem cells, compared
to embryonic stem cells. They are more difficult to isolate,
exist in smaller numbers, and researchers have not been able
to isolate stem cells from all of the adults' tissues. It
has been suggested that adult stem cells may have more genetic
errors than embryonic stem cells, and these errors could be
perpetuated in the cultured stem cells.
Dr.
Daniel Furst has been in the news for his stem-cell rescue
involving scleroderma patients. What does his procedure consist
of?
The procedure used
by Dr. Furst in Seattle and by other centers in Detroit and
California consists of isolating stem cells from the blood
of the patient who will be receiving the transplant. These
stem cells are preserved for later reintroduction to the body
of that same patient.
Next, the patient
is given chemotherapy and total body radiation. This destroys
all the body's immune system cells. The reasoning is that
the patient's existing immune system is not functioning properly,
and needs to be replaced.
The stored stem
cells are then reinfused into the patient's blood stream.
The therapeutic goal is for the stem cells to take up residence
in the patient's bone marrow and begin to function as a normal
immune system. This is called an autologous transplant.
This stem cell
procedure does not use embryonic stem cells and therefore
is different from the type of stem cell research that has
recently been in the news.
What
kind of stem cell research was President Bush talking about
when he announced the federal government's guidelines?
President Bush
has made a decision to allow federal funding of research through
NIH using existing "stem cell lines." These are
stem cells whose original sources were human embryos. The
President stated the 60 existing stem cell lines have "great
promise that could lead to breakthrough therapies and cures.
This allows us to explore the promise and potential of stem
cell research without crossing a fundamental moral line by
providing taxpayer funding that would sanction or encourage
further destruction of human embryos that have at least the
potential for life" (cnn.com, August 10, 2001).
President Bush
has also endorsed increased funding for research on stem cells
obtained from adults and from umbilical cords, placentas,
and animals. About $250 million will be spent on this type
of research this year.
The President has
also announced the creation of a council on bioethics, responsible
for monitoring scientific and ethical concerns as the research
proceeds. This council will be chaired by Leon Kass, M.D.,
Ph.D., of the University of Chicago.
What
is the Scleroderma Foundation's position on stem cell research?
The Scleroderma
Foundation has consulted its Medical Advisory Board, chaired
by Maureen Mayes, M.D., for a position on this matter. The
Medical Advisory Board has stated: "The Scleroderma Foundation
supports excellence in medical research and will follow the
guidelines of the NIH regarding the conduct of research."
Is
stem cell research likely to help find a cure for scleroderma?
It is much too
early for us to answer this question, but at the very least
stem cell research may become important in the future by helping
researchers understand the basics of how cells work.
We
are here to help you
We hope this information
helps you weave your way through all the information on the
news about stem cell research. Please be sure to call us at
the Scleroderma Foundation's National Office if you need further
clarification (800-722-HOPE). We can also help you find medical
centers, in addition to Dr. Furst's in Seattle, that are doing
adult stem cell rescue for patients with severe systemic scleroderma.
Acknowledgement
We thank Daniel
Furst, M.D., for reviewing this article for accuracy.
Additional
Reading
Below we list some
references if you want to leam more about stem cell research.
Publication
National Institutes
of Health, Stem Cells: A Primer (May 2000)
Websites
(search them for phrase "stem cell")
www.cnn.com
www.sciam.com
www.usatoday.com
Medical Research
Center
Virginia Mason Medical
Center, Seattle, Washington. |
