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ETHICS AND THE ENGINEER:
MAKING AN ETHICAL DECISION ABOUT STEM CELLS BASED OF OFF
CURRENT ETHICAL CODES AND GUIDELINES
Gabrielle Schantz ([email protected])
INTRODUCTION: ENGINEERING CODES
OF ETHICS AND THE RESEARCH DESIGN
PROCESS
Bioengineering uses basic engineering principles and
applies them to the biological world. This creates the need to
approach ethically-charged situations with respect to current
engineering ethics and medical ethics. To do so, I must use
the National Society of Professional Engineers (NSPE) Code
of Ethics for Engineers and the Biomedical Engineering
Society (BMES) Code of Ethics. These codes of ethics are a
major source of ethical guidance for professional
bioengineers. The NSPE Code of Ethics for Engineers
involves the obligations that engineers must follow to
truthfully and legally engage in research and design settings.
Furthermore, the BMES Code of Ethics includes values
outlined by the NSPE Code of Ethics along with medical
research ethics and training ethics of bioengineering.
Throughout this essay, I will determine the effectiveness
of these codes of ethics as well as how they will help me in
facing the ethically-charged issue of using stem cells in an
artificial skin substitute for burn patients. Additionally, I will
have to utilize sources about engineering ethics and other
necessary resources that will help me come to a decision on
using embryonic stem cells to create an artificial skin graft
for use on severely burned patients.
SETTING THE SCENE: STEM CELL
RESEARCH AND SKIN TISSUE
ENGINEERING
Structure of Skin and Types of Burns
A basic understanding of the structure of skin and the
types of burns is needed to understand my proposed research
of artificial skin materials. To start off, the skin is composed
of two major layers called the epidermis and the dermis. The
epidermis is the outer layer of skin that protects the inside of
the body from the environment, and the inner-layer called
the dermis allows the skin to be flexible [1]. The amount of
damage that occurs to these layers of skin determines the
category into which a burn falls. These categories are
epidermal burns, superficial partial-thickness burns, deep
partial-thickness burns, and full-thickness burns. Only deep
partial-thickness and full-thickness burns are relevant to my
proposed design because they require the use of skin grafts
in their treatment. Deep partial-thickness burns occur when
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the epidermis and a majority of the dermis are damaged and
very few regenerative cells remain, whereas full-thickness
burns occur when both the epidermis and dermis are
completely destroyed [2].
The Problem With Current Treatments and the
Solution
For my research design, I will focus on the treatment of
deep-partial thickness and full-thickness burns. These can be
treated with dermo-epidermal skin substitutes, which are the
most advanced bioengineered skin material due to the fact
that they contain both an epidermal and dermal component.
[2]. However, all artificial skin substitutes tend to have the
same major problem of immunogenicity (the ability to cause
an immune response). The immune system reacts to the
artificial skin grafts just as it would towards an infection.
The immune response starts out when donor dendritic cells
(DCs) migrate from the graft into the lymph nodes of the
patient. Here, the T-cells become activated and reproduce to
secrete inflammatory cytokines, which travel back to the
graft and kill the donor skin cells [3].
In order to decrease the amount of immunogenicity of
the artificial skin grafts, I am considering using stem cells
because they typically are not rejected by the body’s. The
design will consist of a dermo-epidermal skin substitute that
combines a sheet of epidermal stem cells with a dermal stem
cell scaffold because it allows for specific stem cell
microenvironments to influence stem cell function through
biochemical and physical cues, which means that the cells
will train themselves to become functioning skin cells [4].
However, the usage of stem cells creates the ethicallycharged scenario of choosing between embryonic stem cells
and adult stem cells for use in the design. In order to
determine whether or not I will use embryonic stem cells in
my research, I must follow the engineering codes of ethics,
while considering input about the codes and other resources
specific to stem cell research.
THE CODES AND THEIR APPLICATION
TO THE SITUATION
As a future engineer, there are codes that have been set
in place to help me make rational and ethical decisions.
However, not all of the canons and codes are applicable to
my research scenario and many of them seem to be
ineffective in guiding me in the decision making process.
They are ineffective because they mostly deal with
Gabrielle Schantz
confidentiality between employers, clients, and engineers.
However, two major canons of the NSPE Code of Ethics for
Engineers apply to my scenario. These are to “hold
paramount the safety, health, and welfare of the public,” and
to, “conduct [myself] honorably, responsibly, ethically, and
lawfully so as to enhance the honor, reputation, and
usefulness of the profession” [5]. Unfortunately, these two
canons are unclear and vague as to what they actually mean.
I could interpret them as saying do what is necessary to
make an artificial skin material that benefits the community
as long as it is within legal regulations. I could also interpret
them as stating that I determine what is ethical while
creating a safe and effective product for the community. The
ability to freely interpret the codes makes it hard to
understand what my specific obligations are.
Thankfully, there are societies that are more disciplinefocused, such as the Biomedical Engineering Society
(BMES) Code of Ethics. The BMES Code of Ethics
describes the obligations that bioengineers need to follow
with respect to health care and research. According to these
codes, bioengineers must, “regard responsibility toward and
rights of patients, including those of confidentiality and
privacy” [6]. Additionally, in their research bioengineers
must, “comply fully with legal, ethical, institutional,
governmental, and other applicable research guidelines,
respecting the rights of and exercising the responsibilities to
colleagues, human and animal subjects, and the scientific
and general public” [6]. These codes tell me that I must
follow all outlined guidelines for stem cell research, such as
federal and state regulations. Furthermore, the BMES code
of ethics force me to consider the implications and risks of
stem usage on the test subjects and I will protect the privacy
of the test subjects and the source of the stem cells. The
BMES code of ethics is more effective than the NSPE code
of ethics, but still lacks substantial direction and guidance.
involves destroying a human embryonic cell in order to
obtain the stem cells. This directly involves considering the
sanctity of human life, which is why the topic is so
controversial. Furthermore, the Nuremberg Code revolves
around human experimentation and emphasizes voluntary
and informed consent from test subjects, and the Declaration
of Helsinki provides guidance on the topics of human test
subjects, human materials like skin or tissue [7].
However, after consulting another source about tissueengineering ethics a major problem came to my attention.
The problem lies in the fact that embryonic stem cell
research causes the Hippocratic Oath and the Nuremburg
Codes to conflict with one another. The protection of donor
privacy (Hippocratic Oath) conflicts with the ideal of
informed consent (Nuremberg Codes) because the intended
use of the stem cells is not always specifically clear at the
time of donation. This causes a need for some identifiable
data to remain attached to the donated cells, which can
inhibit the privacy of the patient [8]. Additionally, the testing
of the engineered tissues can result in unclear informed
consent due to the fact that most tissue-engineered products
do not have clear long-term side effects after implantation
[8].
To determine a possible solution to this ethical dilemma
of informed consent, I looked into the National Institutes of
Health (NIH) Guidelines on Human Stem Cell Research.
The guidelines provide for informed consent from the
donor(s) at the time of donation of excess embryos for
clinical need. The consent is to come from the individual(s)
who sought out the medical treatment because the
individual(s) receiving the treatment are responsible for the
creation of the embryos [9]. Additionally, I would be
allowed to use stem cells that are already in the NIH
Registry of stem cells. But, if I want to use cells outside the
registry, then I must be able to provide all necessary
documentation that clearly defines the source of the stem
cells and that they were ethically obtained [9]. However
according to the Declaration of Helsinki, if I use the stem
cells from the NIH registry, which have identifiable human
material, then I must seek the informed consent for its
collection, storage, and/or reuse [10]. These guidelines are
very specific in the necessary procedures and ethics involved
with using embryonic stem cells, and have helped clarify the
problems associated with obtaining the embryonic stem cells
for use in my research design.
INPUT ABOUT ENGINEERING ETHICS
THAT SHAPED THE FINAL DECISION
Even though the BMES code of ethics is more explicit
than the NSPE code of ethics, I still need to consult outside
sources that pertain to ethics within engineering. One article
that helped me understand other codes and ethical
obligations I may have to face was, “Ethics for
Bioengineers” by Monique Frize within Synthesis Lectures
on Biomedical Engineering. The article states that
bioengineers involved in health care should also consult
codes that are addressed towards medical physicians, such as
the Hippocratic Oath, The Nuremberg Code, and the
Declaration of Helsinki. The Hippocratic Oath provides
moral and ethical obligations regarding, “the sanctity of
human life, relief of suffering, [treating] the ill to the best of
one’s ability, [and preserving] a patient’s privacy and
confidentiality [7]. This applies to the decision on using
embryonic stem cells because embryonic stem cell research
INFORMATION ABOUT STEM CELL
MORALITY AND ETHICS
Following the codes of ethics in the ethical decision
making process is important, but there are also ways of
gathering ethical input that can be just as useful. For
example, I was able to find a Gallup Poll about American
opinions on the morality of embryonic stem cell research.
According to the poll, 60% of Americans believed it was
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morally acceptable to use stem cells derived from human
embryos in medical research, 32% of Americans believed it
to be morally wrong, and the remaining 10% either did not
have an opinion or claimed the opinion depended on the
situation. This approximately 60/30 split in opinion has
remained relatively constant for the past four years [11].
This information suggests that the majority of Americans are
in favor of medical research using human embryonic stem
cells, which allows me to infer that the majority of
Americans would also be in favor of my research scenario.
Of course, this inference does not take into account their
opinion on artificial skin-engineering, but is still valid from
the view of that the research will be used for medicinal
purposes.
reproduce and divide longer. They are also safer than other
types of stem cells, such as inducible pluripotent adult stem
cells, which are adult stem cells that have been
reprogrammed to act like embryonic stem cells. The
inducible pluripotent stem cells have the same abilities as
embryonic stem cells, but have a higher likelihood of
uncontrolled growth [14]. The uncontrolled growth could
potentially lead to malignant tumors, resulting in cancer.
This makes using these stem cells potentially dangerous and
life-threatening, especially since there is little long-term data
on these reprogrammed cells.
Another source of stem cells is bone marrow. Bone
marrow derived stem cells could be a very useful and
effective source of stem cells because bone marrow derived
stem cells produce endothelium (skin) cells that lack
immunogenicity. Their lack of immunogenicity could be
seen when bone-marrow derived stem cells were added to
lymphocytes (T-cells). The stem cells suppressed leukocyte
(white blood cells responsible for riding the body of disease)
proliferation by 50% [13].
Additionally, adipose derived stem cells have a major
advantage over both embryonic stem cells and bone-marrow
derived stem cells because they can be obtained from the
discarded fat tissue of liposuction procedures. Adipose tissue
can yield 100 to 1,000 times more cells per cubic centimeter
than bone marrow tissue and also has immunogenicity that is
almost 90% identical to that of bone-marrow [13]. This
makes adipose derived stem cells easier to obtain and just as
valuable as bone-marrow derived and embryonic stem cells.
Each type of stem cell has their pros and cons, which are
important in deciding whether any of them are more
reasonable to use than embryonic stem cells in my design.
BREAKING DOWN THE PROBLEM
Additionally, the article, “Teaching Ethics to Engineers:
Ethical Decision Making Parallels the Engineering Design
Process,” written by Bridget Bero and Alana Kulhman of
Northern Arizona University, was particularly helpful in
outlining a procedure for breaking down an ethical problem
to come to a clear concise decision. [12]. I followed the
layout to break down the ethical problem of using embryonic
stem cells in my research of the artificial skin graft.
First, I had to list the relevant moral factors and
dilemmas that I am faced with. These included such as using
stem cells that have been obtained by destroying a human
embryo and deciding whether the source of the cells is
ethically just. Second, I had to consider the applicable moral
theories, which included public approval of the usage of
stem cells in research along with the benefits to using the
stem cells (i.e. the reduced risk of immune system rejection
in artificial skin grafts). Additionally, I had to take into
account the ethical guidelines from the NSPE Codes of
Ethics, the BMES Code of Ethics, and applicable medical
codes of ethics, such as the Hippocratic Oath, The
Nuremberg Codes, and the Declaration of Helsinki. The
third step involved developing alternate courses of actions
and their advantages and disadvantages, which in my case
are alternatives to embryonic stem cells, which include
bone-marrow derived stem cells and adipose (fat tissue)
derived stem cells[13]. These alternatives and the
advantages and disadvantages are presented in the
subsequent section. The fourth and final step in process
would be to determine the best course of action and justify
the reason.
THE FINAL COURSE OF ACTION
After considering the different alternatives that could be
used and the ethics involved with embryonic stem cells, I
have decided to use only those embryonic stem cells that
have been created in excess for medical purposes. I have
decided this because embryonic stem cells are lacking in
data that support how well they work in artificial skin
substitutes and my goal is to determine the efficacy of
embryonic stem cells to reduce immunogenicity. However,
if they prove to be ineffective or equal to the effectiveness of
other stem cells, I would immediately stop using the
embryonic stem cells in my research because there would be
no logical reason to continue using the embryonic stems if
there is a more effective alternative.
I was able to come to this conclusion despite lacking
explicit guidance from the ethical codes set in place for me
as a bioengineer and as an engineer in general. The
challenges with the current codes that I had to overcome
included the vagueness of the current codes of ethics for
bioengineers and the lack of codes about research in the
NSPE codes of ethics. In order to overcome this lack of
guidance, I had to utilize other ethical codes and federal
THE ADVANTAGES OF SPECIFIC STEM
CELLS
Human embryonic stem cells have some advantages over
stem cells that come from an adult source because
embryonic stem cells have the ability to differentiate into
almost any type of cell (pluripotent) and the ability to
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Gabrielle Schantz
regulations, along with opinion polls to determine how
ethical the use of embryonic stem cells would be. The
challenges that I face are the main reason as to why I believe
improvements need to be made to these codes that are open
to a wide array of interpretation.
http://www.nspe.org/resources/pdfs/Ethics/CodeofEthics/Co
de-2007-July.pdf
[6] (2004). “Code of Ethics.” Biomedical Engineering
Society.
(Online
Publication).
http://bmes.org/files/2004%20Approved%20%20Code%20o
f%20Ethics(2).pdf
[7] M. Frize. (2012). “Ethics for Bioengineers.” Synthesis
Lectures on Biomedical Engineering, lecture #42, J. Enderle.
Morgan & Claypool Publishers. (Electronic book). pp. 9-11.
http://www.morganclaypool.com/doi/pdf/10.2200/S00393E
D1V01Y201111BME042
[8] A.J.M. Oerlemas, M.E.C. van Hoek, E. van Leeuwen, S.
van der Burg, W.J.M. Dekkers. (2012). “Towards a Richer
Debate on Tissue Engineering: A Consideration on the Basis
of NEST-Ethics.” Springer Science+Business Media.
http://link.springer.com/article/10.1007/s11948-012-9419y/fulltext.html
[9] National Institutes of Health, U.S. Department of Health
and Human Services (2011). “2009 Guidelines on Human
Stem Cell Research.” Stem Cell Information. (Online
Article).
http://stemcells.nih.gov/policy/pages/2009guidelines.aspx
[10] World Medical Association General Assembly. (2013).
“WMA Declaration of Helsinki – Ethical Principles for
Medical Research Involving Human Subjects.” World
Medical
Association,
Inc.
(Online
Article).
http://www.wma.net/en/30publications/10policies/b3
[11] (2013). “Stem Cell Research.” Gallup.com. (Online
Poll).
http://www.gallup.com/poll/21676/stem-cellresearch.aspx
[12] B. Bero, A. Kuhlman. (2010). “Teaching Ethics to
Engineers: Ethical Decision Making Process Parallels the
Engineering Design Process.” Springer Science+Business
Media.
(Online
Report).
http://link.springer.com/article/10.1007%2Fs11948-0109213-7/fulltext.html
[13] K. Butler, J. Goverman, H. Ma, A. Fishman, et al.
(2010). “Stem Cells and Burns: Review and Therapeutic
Implications.” Journal of Burn Care & Research, Vol. 21,
Issue 6, American Burn Center. (Online Article). pp. 874881. DOI: 10.1097/BCR.0b013e3181f9353a.
[14] J. Shand. J. Berg, C. Boque. (2012). “Human
Embryonic Stem Cell (hESC) and Human Embryo
Research.” Pediatrics, Vol. 130, No. 5, American Academy
of
Pediatrics.
(Online
Article).
pp.
972-977.
http://pediatrics.aappublications.org/content/130/5/972
CONCLUSION: IMPROVEMENT OF THE
BIOENGINEERING CODES
Possible improvements of the current BMES Code of
Ethics include the addition of ethical codes and tenets that
apply to medical professionals, such as the Hippocratic
Oath, the Nuremburg Code, and Declaration of Helsinki. By
including these ethical codes directly in the BMES Code of
Ethics, it will clear up discrepancies between the
responsibilities of a bioengineer as an engineer and as a
medical researcher. Additionally, from the struggles faced
from trying to interpret the NSPE Codes of Ethics for my
specific scenario, I believe that it needs to incorporate ethics
about research done by an engineer in addition to the
confidentially between employer and engineer. However, I
do take into account that the NSPE Code of Ethics is for
engineers in general and not directed towards any one
specific engineering discipline, which may have made it
difficult to involve any decisions about ethical research
principles and guideline due to the expansive nature of
engineering as a whole. Even if they are not improved,
bioengineers, and engineers in general, should look to the
codes as a starting point towards handling an ethicallycharged research design.
REFERENCES
[1] C. Brohem, L. Beatriz da Silva Cardeal, M. Tiago, M.
Soengas, S. Berlanga de Moraes Barros, S. Stuchi MariaEgnler. (2011). “Artificial Skin in Perspective: Concepts and
Applications.” National Institute of Health Public Access.
(Online
Journal
Article).
http://dx.doi.org/10.1111%2Fj.1755-148X.2010.00786.x
[2] R. Shevchenko, S. James, S. E. James. (2010). “A review
of tissue-engineered Skin Biocontructs Available for Skin
Reconstruction.” Journal of the Royal Society Interface.
(Online
Journal
Article).
http://rsif.royalsocietypublishing.org/content/7/43/229
[3] G. Benichou, M. Fray, C. Lin, G. Tocco, Y. Yamada, S.
Yun. (2011). “Immune Recognition and Rejection of
Allogeneic Skin Grafts.” Future Medicine Ltd. (Online
Report). http://dx.doi.org/10.2217/imt.11.2
[4] V. Wong, D. Wan, G. Gurtner, M. Longaker. (2012).
“Regenerative Surgery: Tissue Engineering in General
Surgical Practice.” World Journal of Surgery, Vol. 36, Issue
10, International Society of Surgery. (Online Article). pp.
2288-2299. DOI: 10.1007/s00268-012-1710-1
[5] (2007). “Code of Ethics for Engineers.” National Society
of
Professional
Engineers.
(Online
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Acknowledgements
I would like to thank Jake Cline for proofreading my
essay. I would also like to thank my writing instructor John
Calvasina for answering questions about the assignment.
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