Bursic 2:00
R07
THE USE OF MESENCHYMAL STEM CELL THERAPY AS AN
ETHICAL FUTURE TREATMENT OPTION FOR SPINAL CORD
INJURIES
Emily Pinto (eap72@pitt.edu)
INTRODUCTION: STEM CELL THERAPY
AND THE ETHICAL CONCERNS OF THE
CONTINUATION OF RESEARCH
Stem cell transplants using adult stem cells are a
promising option for the treatment of patients
suffering from spinal cord injury and are traditionally
considered entirely ethical. I am currently researching
the use of stem cells to facilitate spinal cord recovery
which is an effective and viable treatment option that
will lead to significant medical developments in the
future. Research on animal models has proven that, in
certain cases, loss of function caused by spinal cord
damage can be reversed or partially reversed by
injection of stem cells to the afflicted area. This is a
prevalent issue because there are approximately 320
per million people in the US affected by spinal cord
injuries [1] who could be helped by advances in stem
cell treatments. The research, however, is often
hindered when the U.S. government acts to appease
radical protest groups that oppose any and all
development of stem cell treatments by funding cuts.
These groups protest on the grounds that stem cell
research is unethical because the stem cells are taken
from destroyed embryos which is the equivalent, in
their eyes, of a destroyed life. I am seldom forced to
deal with any major adverse affects or ethical concerns
of the embryotic stem cell debate because the use of
embryotic stem cells for treatment of spinal cord
injuries is uncommon and adult stem cells, or
mesenchymal stem cells, are a more appropriate cell to
use for the rehabilitation and remyelination of the
spinal neurons. The ethics of my research however
was brought to my attention when a group of
protestors sat outside my lab after hearing that I was
conducting stem cell research. It was my first instinct
to tell them they were misinformed, I was only
studying mesenchymal stem cells, and that there was
absolutely nothing unethical going on in my lab.
Before I went outside, however, I decided to consider
if any of my research is at all unethical. To do this I
compared mesenchymal cells to the embryotic cells
they thought I was researching. I not only considered
if my research was socially ethical, but also consulted
the National Society of Proffesional Engineers’
(NSPE) and the Biomedical Engineering Society’s
(BES) code of ethics to make sure that my research is
ethical by engineers’ standards. After considering all
aspects of the future use of my research in a health
services setting in relation to individual patients, the
public, and the engineering field I determined that my
research was in fact ethical by every cannon/directive
that applied.
THE DIFFERENCES BETWEEN
MESENCHYMAL STEM CELL AND
EMBRYOTIC STEM CELL RESEARCH FOR
STEM CELL THERAPY
To determine if mesenchymal stem cells are more
ethically acceptable to research than are embryotic
stem cells I compared the sources, useage, and end
product of each when used for stem cell therapies.
Embryotic vs. Adult Stem Cells
A few main differences between embryotic stem cells
and adult stem cells brand one unethical and the other
ethical, by the general public opinion. They differ
most notably in their origin, lineages, and usage in
stem cell treatments. Embryotic stem cells are cells
that are isolated in the oocytes or blastomeres from,
“‘spare’ embryos produced by in vitro fertilization or
by the fusion of sperm and egg” [2]. These cells are
the most adaptable cells to use for stem cell therapies
because they are the least developed and can therefore
take the phenotype of many different lineages [3].
They are versatile enough that they can differentiate
into any one of the three embryonic germ layers;
endoderm, ectoderm and mesoderm, which allows
them to be applicable in treatments for an extremely
wide variety of conditions and diseases [2].
Mesenchymal stem cells are found in blood, adipose
tissue, and lungs [1], but it is the cells taken from bone
marrow that are most commonly used [4]. Unlike
embryotic stem cells, the possible lineages a
mesenchymal cell can follow are somewhat more
limited due to the partial development of the cells in
the adult body [5]. “Adult stem cells could be induced
to differentiate exclusively into the adipocytic,
chondrocytic, or osteocytic lineages,” meaning that
the mesenchymal cells will never difeerentiate into
anything except “bone, cartilage, fat, tendon, muscle,
and marrow stroma” [6]. In the case of spinal cord
injury treatment, the cells normally require direction
into oligodentrocytes, a cell that is responsible for the
Emily Pinto
remyelination of axons in the central nervous system
[7].
The Ethical Concerns of Mesenchymal Stem Cell
Research Compared to Embryotic Stem Cell
Research
Embryotic stem cell research is an extremely
controversial topic because embryotic stem cells are
derived exclusively from the destruction of a fertilized
egg, which could otherwise develop to term if
implanted [2]. The ethical argument is that the
destruction or utilization of stem cells is parallel to the
destruction of a human life, is therefore immoral, and
possibly considered murder.
Research of
mesenchymal cells is not controversial because they
were not derived from and their lineage does not allow
differentiation into anything involving independently
sustainable life.
Why This is Important to Consider?
I must consider if what I am researching is ethically
acceptable because as a professional biomedical
engineer I must abide by all of the applicable cannons
and directives of the NSPE and the BES codes of
ethics and by the sixth cannon on the NSPE code of
ethics I am required to I act ethically [8].
DO ENGINEERS CONSIDER MY RESEACH
ETHICAL?
The ethical expectations of professional engineers are
outlined in the principles, cannons, and directives of
the NSPE Code of Ethics, all of which I am obligated
to follow. Although through my research I could find
myself in situations for which many of the cannons or
directives could apply, currently only a few are
applicable enough for my questioning. The first, and
perhaps the most important cannon of the NSPE Code
of Ethics, provides a clear guide for what kind of
engineering projects should be pursued. It states,
“Engineers in the fulfilment of their professional
duties, shall: Hold paramount the safety, health, and
welfare of the public” [8]. The mesenchymal stem cell
research that I do in the lab will directly lead to
developments in stem cell therapy for spinal chord
injury patients which not only protects, but improves,
the safety, health, and welfare of the public. In
technical terms, my research will to stem cell
transplants that will offer a potential way to increase
the number of oliodendrocytes (remeyilinating cells)
while keeping the benefits of the glial scar (an anti
inflammatory source). Stem cells have been proven in
animal models to improve and repair partially
damaged axons, reduce the size of the cyst cavity, and
restore the myelin shealth around the neurons [1].
Improvement in any of these areas after a spinal cord
injury can result in greater recovery of functions [10].
Advancements in medicine such as these comply with
the first cannon of the NSPE Code of Ethics because
the direct functional improvement in spinal cord injury
patients hold the safety, health, and welfare of the
public as top priority. In addition to these publicly
helpful engineering achievements, the indirect
contribution that my research will make to the
knowledge base for the development of mesenchymal
stem cell therapies for other conditions or diseases will
help the engineering community and eventually all of
society. These aspects of my research are not only
ethical by the NSPE Code of Ethics, but also by the
BES Code of Ethics section I.1 where it states,
“Biomedical Engineers in the fulfilment of their
professional engineering duties shall: Use their
knowledge, skills, and abilities to enhance the safety,
health, and welfare of the public” [9]. This directive
is similar in most ways to the NSPE Code of Ethics
first cannon.
My research can also be deemed ethical by the
sixth cannon of the NSPE Code of Ethics when it
states, “Engineers, in the fulfilment of their
professional duties, shall: Conduct themselves
honorably, responsibly, ethically, and lawfully, so as
to enhance the honor, reputation, and usefulness of the
profession” [8]. It is my opinion and the opinion of
the scientific community that my research will lead to
a treatment option that is extremely useful. Current
treatment for spinal cord injuries is limited to nonexistent making any effective treatment option
introduced an enormous benefit to the medical
community. A stem cell therapy that can help spinal
cord patients regain function will transform the way
we look at spinal cord injuries and will be used to treat
almost every single new spinal cord injury case in the
future. To demonstrate how “useful” a preferred
treatment option will be, I will describe the current
treatment options: When faced with a patient
suffering from spinal cord injury today, doctors can
reduce inflammation to limit further damage to nerves
or offer patients the option of surgery to remove the
glial scar. Surgury could potentially be beneficial
because the inhibitor that prevents the regeneration of
axons and production of oliodendrocytes comes from
the glial scar that forms about the lesion [11].
Removal of this scar would allow the body to produce
more oliodendrocytes that could improve the amount
of recovered function [1]. Unfortunately, the glial scar
also produces inflammatory inhibitors and molecules
that promote recovery [4] so removing it is not as
simple of a choice as it would seem. Surgery may help
in some ways, but hinder recovery in others, making it
a flawed option for optimal recovery. A mesenchymal
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stem cell treatment option would be an obvious choice
over removal of the glial scar and would therefore be
used by doctors every day, all over the world.
CONCLUSION: STEM CELL THERAPY AS
AN ETHICAL TREATMENT FOR FUTURE
SPINAL CORD INJURY
Stem cell therapy is not only the most efficient option
for the treatment of spinal cord injuries but it is also a
completely ethical one by societies and engineers’
standards. Continued research in this field will
advance the engineering and the medical field by
immeasurable amounts. The general public will soon
have little choice but to accept the progression of stem
cell therapy because of the millions of people it will
help, including spinal cord injury and other paralysis
patients. Breakthroughs in this field will allow doctors
and scientists to do things unimaginable by using
current treatments, such as giving a patient with a
severed spine the ability to run again. The possibilities
for helping society by curing conditions and diseases
are endless.
Emily Pinto
References
[1] E. Kan. (2010). “Stem Cell Therapy for Spinal
Cord Injury.” Current Medicinal Chemistry. (Online
Article). 10.2174/092986710794182971.
[2] Rippon, H. J. and Bishop, A. E. (2004),
Embryonic stem cells. Cell Proliferation, 37: 23–34.
doi: 10.1111/j.1365-2184.2004.00298.x
[3] E. Eftekharpour. (February 3, 2010). “Synergistic
Effects of Transplanted Adult Neural
Stem/Progenitor Cells, Chondroitinase, and Growth
Factors Promote Functional Repair and Plasticity of
the Chronically Injured Spinal Cord.” The Journal of
Neuroscience. (Online Article).
[4] M. Osaka. (9 July 2010). “Intravenous
administration of mesenchymal stem cells derived
from bone marrow after contusive spinal cord injury
improves functional outcome.” Brain Research
volume 1343. (Research Report).
http://www.sciencedirect.com/science/article/pii/S00
06899310010905.
[5] B. Sandner. (3 March 2012). “Neural Stem Cells
for Spinal Cord Repair.” Cell and Tissue Research
Volume 349 Issue 1. (Online Article).
10.1007/s00441-012-1363-2.
[6] Pittenger, M. F., & Mackay, A. M., & Beck. S.
C., et al. (April). Multilineage Potential of Adult
Human Mesenchymal Stem Cells. Science, 284, 143147. DOI: 10.1126/science.284.5411.143
[7] M. Bradl. (Jan. 2010). “Oligodendrocytes:
biology and pathology.” ***. (Online Article).
10.1007/s00401-009-0601-5.
[8] NSPE. (October 29, 2013). NSPE Code of Ethics
for Engineers. Retrieved from
http://www.nspe.org/Ethics/CodeofEthics/index.html
[9] Biomedical Engineering Society. (24 October
2011). Biomedical Engineering Society Code of
Ethics. Retrieved from
http://ethics.iit.edu/ecodes/node/3243
[10] J. Kluger. (July 31, 2012). “A Breakthrough at
Last for Spinal-Cord-Injury research?” Time Health
[11] J. Silver. (February 2004). “Regeneration
beyond the glial scar.” Nature Reviews Neuroscience.
(Online Article). 10.1038/nrn1326.