ENGR0011 Vidic 2:00
Group R01
REGENERATIVE ENGINEERING: BUILDING THE SCAFFOLDING OF
TOMORROW
Rachel Lukas (rel43@pitt.edu)
PREAMBLE
Often, freshman engineering students enter college as
undergraduates without any awareness of what it truly
means to be an engineer. They often see the profession as
being simple and straight forward, an easy way to make
money. However, engineering is much more substantial than
that. In this paper I will divulge into the specifics of a branch
of bioengineering that is of great importance to me
personally. Furthermore, I will explain the significance of
ethics in this engineering field along with why an
assignment such as this is vital for undergraduate freshmen
to take on.
body using the patient’s own cells and implant the organ
back into the patient. The development of bioengineered
organs not only minimizes the need for conventional organ
transplants, but also allows regenerative engineers and
doctors to increase the survival rates of patients with a
fabricated organ after transplant surgery. Implanting an
engineered organ greatly reduces the possibility of a
patient’s body rejecting the organ since it is composed of the
patient’s cells rather than foreign cells [2].
WHAT COULD YOU POSSIBLY GROW
FROM HUMAN CELLS?
Bioengineered Bladders
THE DOOR TO A NEW WORLD OF
MEDICINE OPENS
How to resolve a growing crisis
Today, there is a growing international medical
emergency, one that affects individuals in every country in
the world. This crisis is the growing global scarcity of donor
organs for those who are in need of a transplant. In fact,
“more than 100,000 people are waiting for organ transplants
in the U.S. alone; every day eighteen of them die” [1]. Even
in the event where a donor organ can be obtained, the
receiving patient still runs the risk of their body rejecting
newly implanted tissues or organ. It is because of this that
scientists are developing innovative alternatives to
traditional organ and tissue replacements through a new
branch of medical science called regenerative engineering.
WHAT IS IT AND WHY IS IT IMPORTANT?
Regenerative engineering includes a broad range of
disciplines ranging from creating living, usable tissues to the
repair of damaged parts of the body, to allowing organs to
heal themselves in ways that once seemed to be impossible.
Perhaps most significantly, regenerative engineering allows
scientists to develop full-functioning organs outside of the
In 2006 an experiment was conducted on children and
young adults who were affected by spina bifida, a birth
defect that causes bladders to function poorly, often leading
to a host of medical issues including kidney failure [3]. In
the experiment, bioengineered bladders crafted from the
patients’ natural bladder cells were implanted into these
patients. The laboratory-grown bladders were created by
placing the patients’ cells, obtained from a biopsy of their
bladders, onto a scaffold. This scaffold was a biomaterial
created from a deceased bladder whose original cells were
“washed” away, leaving only the basic skeleton of the
bladder behind. Next, the patients’ bladder cells were placed
onto the scaffold which acted as a bridge for the cells so they
could adhere to it and multiply. After a month of growing
the cells on the scaffold, the new bladder structure was
incubated in an oven-like device that mimicked the human
body’s natural conditions, thirty-seven degrees centigrade
with ninety-five percent oxygen. The bladder then remained
in incubation for a few weeks until the tissues matured [4].
Then, the bladder was transplanted into the patients’ body
where nerves and blood vessels naturally grew into place,
allowing the bioengineered bladder to function as if it were
natural [3]. The results of the experiment were highly
successful with none of the patients experiencing a rejection
of the new bladder [4]. The success of the bioengineered
The University of Pittsburgh, Swanson School of Engineering
October 6, 2012
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Rachel Lukas
bladders opened the doors to the development of other types
of tissues.
Can these printers make any other tissues?
Additionally, Atala and his team have modified a
desktop inkjet printer to produce structures that can
immediately be implanted into a patient upon completion.
This printer works like an elevator, creating one layer of
cells at a time to produce a three dimensional, bioengineered
scaffold. For example, Atala and his team have successfully
developed a method of printing bone segments that have
been implanted into several patients [4]. In viewing X-ray
images of the bioengineered bone, the tissues have been
fully regenerated to the point where it is difficult to
determine where there was natural bone and where it was
biologically engineered. Furthermore, Atala and his team
have been developing technology that can directly attach
cells to injured patients at the site of an injury. Essentially, a
flatbed scanner goes over a patient’s laceration and develops
a summary of the tissues that are in need of repair.
Subsequently, a printer then takes that information and
creates the necessary tissues, layer by layer, directly onto the
patient’s wound [4]. Once this technology is fully
developed, it would hasten the healing process and recovery
times of severe wounds in emergency situations and
decrease the need for intensive surgery to repair damage
caused by serious injuries.
Reconstructing an Esophagus
Regenerative engineers are also developing cures for
esophageal injuries and congenital long-gap esophageal
atresia, a birth defect where the esophagus does not connect
to the stomach normally. These treatments are still in
development, and have only been tested on laboratory rats;
however, these experiments show a great deal of promise. In
the rat tests, cells from the test subject were again transferred
to a biomaterial scaffold where the esophageal cells were
able to reproduce and form tissues. Then, the tissue was
implanted back into the rats. After ten and sixteen weeks
post-implantation of the bioengineered esophageal tissue, the
test rats were sacrificed and dissected to view the progress of
the inserted tissue. It was found that in both groups of rats,
the esophagus was readily repairing itself with the help of
the biomaterial scaffold [5]. This experiment shows potential
in the fact that it was so successful in the rats, and it raises
hopes that esophageal regeneration may soon be a viable
treatment for human patients with esophageal damage and
other defects.
A MORE DIFFICULT TASK: VASCULAR
ORGANS
SO, WHAT DOES ALL OF THIS IMPLY?
What Regenerative Growth Offers the Future
“[Our lab uses] a desktop inkjet printer, but instead of
using ink, we're using cells.”
Regenerative growth bioengineering has opened the
door to new therapies for damaged tissues and organs that
were previously thought to be extremely daunting
procedures, if not impossible ones. For example, bladders
and esophageal tissues can be bioengineered outside of the
body using the patient’s own cells. Additionally, vascular
organs such as kidneys, which are more challenging to
create, have been experimentally produced through the use
of highly sophisticated cellular printers. Although only the
bioengineered bladders have been implanted into human
patients, the rest of the aforementioned technologies are not
far behind. These other components of regenerative
engineering each yield great optimism in one day being able
to treat failures or complications associated with birth
defects, diseases, physical damage from injuries, and cancer
in many organs and tissues found throughout the human
body.
Vascular organs, those containing copious amounts of
blood vessels, are more difficult to regenerate than hollow,
sack-like organs such as the bladder [1]. However, Anthony
Atala of the Wake Forest Institute for Regenerative
Medicine in Winston-Salem, North Carolina has developed
an ink-jet printer that can essentially produce copies of any
bodily structure using cells. The printers that Atala and his
team are developing use images from CT scanners or X-rays
to obtain a blueprint for an organ, in this case the kidney.
Using the CT scan, Atala and his team are able to obtain all
of the volumetric characteristics of the patient’s kidney, and
can then transfer the image into a computerized format that
the printer can read. At that point, the printer starts moving
through the organ, level by level, printing cells as it goes
along. In this fashion, a new kidney can be developed for the
patient, using their own cells, in about seven hours [4].
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Rachel Lukas
regenerative engineering alone. Instead, the Biomedical
Engineering Society has refined the NSPE canons in such a
way that they are directly correlated with biomedical
engineering. In turn, the BMES code of ethics can be more
precisely applied to regenerative engineering than the NSPE
standards alone.
The BMES clearly states in their code’s preamble that
“public health and welfare are paramount considerations” for
biomedical engineers [8]. This is reflected in the very
premise of regenerative engineering where the goal is to
improve upon current treatments for congenital defects and
injuries associated with the human body’s tissues and
organs. More specifically, there are two principles in the
BMES code that are extremely important for regenerative
engineering. The first of these statements says that
biomedical engineers must “use their knowledge, skills, and
abilities to enhance the safety, health, and welfare of the
public” [8]. Essentially, this is what regenerative engineers
strive to accomplish. In developing artificial organs and
tissues, regenerative engineers aim to universally improve
the lives of patients through more efficient and successful
transplants of organs. Furthermore, regenerative engineers
are required to “consider the broader consequences of their
work in regard to cost, availability, and delivery of
healthcare” [8]. Anthony Atala and his team are a prime
example of how regenerative engineers abide by these
ethics. Their printers are being designed to operate in any
emergency room, especially the flatbed cell printer that
places the necessary cells directly onto a patient [4]. In
improving this technology, more effective treatments for
injuries will become more widely available. Although cost is
still an issue, this can be minimized with further research
and development of the printers in the future.
A PERSONAL CONNECTION
Several years ago, an event occurred that made me
become determined to remedy the donor organ shortage. In
2007, one of my very close friends was diagnosed with a
tumor on his right kidney; doctors said had to be removed as
soon as possible for fear that it was a malignant, cancerous
tumor. So, at the age of fifteen, my friend lost a kidney and
was put on the waiting list for a donor one, on which his
name remains to this day. Luckily, he has managed to cope
with living with a single kidney; however, he will be held
under close observation for the rest of his life to make sure
that his other kidney preforms as it should. So, when I began
to research possibilities for a future career, I came across the
idea of regenerative bioengineering. Instantly I fell in love
with it and all of the possibilities that regenerative growth
could provide to the medical field. I have confidence that
through developing regenerative technologies, thousands of
people, like my friend, will be able to improve their standard
of living by being able to have their bodies run at their full
potential. Therefore, it is my belief regenerative medicine
will open the gates to a flood of new information about
healing in the years to come and must be thoroughly
explored.
ETHICS: WHO CARES?
The Ethics Resource Center defines a code of ethics as
“a central guide and reference for users in support of day-today decision making” that clearly and explicitly explains in
detail how individuals must perform [6]. Equally, all
engineers are legally and morally required to follow a
specific code of ethics, regardless of their discipline or
concentration. The National Society of Professional
Engineers states in their code’s preamble that “engineers are
expected to exhibit the highest standards of honesty and
integrity” in their work [7]. The NSPE canons reflect these
conditions and specifically exemplify how engineers are
expected to perform. The NSPE code precisely outlines
practices that are acceptable and unacceptable for engineers
to undertake. Furthermore, the code focuses heavily on
avoiding corrupt enterprises, fraud, or unlawful activities.
Engineers are also required to give credit for work and
research when it is due. Additionally, and most importantly,
engineers are required to promote the “safety, health, and
welfare of the public” [7]. Each section of the NSPE ethics
can be applied to every engineering discipline in general.
However, this code of ethics is far too broad to apply to
WHY DO FRESHMEN NEED TO CARE?
An assignment similar to this paper is an important one
for freshman engineering students to undertake for multiple
reasons. First, it required students like myself to research a
current engineering topic that interested them. Individually,
this made me realize the fact that I truly want to major in
bioengineering so that I can one day become a regenerative
engineer. This paper made me look into what technologies
that regenerative engineers are developing, and inspired me
to one day do the same. Furthermore, this assignment is
crucial to incorporate in a freshman curriculum because it
has students investigate the codes of ethics that govern
engineers. Again from my own experience, I know that I had
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Rachel Lukas
a vague notion that a guideline of sorts existed for engineers,
but I never really thought about them in depth. After
researching the codes of ethics that apply to the different
disciplines of engineering, I realized just how important they
are to this profession. Every aspect of engineering, from how
reports are compiled and presented to the experiments that
bioengineers perform, are governed by a code of ethics.
Having freshmen research these policies is crucial in
creating well informed young engineers who are conscious
of the world around them. Therefore, it is my belief that
assignments such as this should be universally adopted in
engineering schools beyond the Swanson School of
Engineering at the University of Pittsburgh.
ADDITIONAL SOURCES
"Esophageal Atresia Symptoms, Treatment, Diagnosis."
(2009). Atresia.info. http://www.atresia.info/esophagealatresia.htm.
ACKNOWLWDGEMENTS
I would first like to thank my dear acquaintance, Kyle
Spies, for giving me the motivation and pressure to keep on
task throughout the entire research process. Additionally, I
would like to thank the librarians in the Swanson School of
Engineering’s library who were extremely accommodating
in helping me gather the necessary information for this paper
from legitimate sources.
REFERENCES
[1] J. Glausiusz. (2011). "The Big Idea: Organ
Regeneration." National Geographic. (Online article).
http://ngm.nationalgeographic.com/2011/03/big-idea/organregeneration-text. p. 1-2
[2] R. Hunziker. (2012) "Regenerative Medicine." National
Institutes
of
Health
(Online
article).
http://report.nih.gov/NIHfactsheets/ViewFactSheet.aspx?csi
d=62. p. 1
[3] R Lovett. (2006) "First Lab-Grown Organs Implanted in
Humans." National Geographic. (Online article).
http://news.nationalgeographic.com/news/2006/04/0404_06
0404_bladders.html. p. 1-2
[4] “Printing a Human Kidney.” TED Conferences LLC.
(2011)
(Video).
http://www.ted.com/talks/anthony_atala_printing_a_human_
kidney.html.
[5] J. Basu, K. Mihalko, R. Payne, et al. (2012). "Extension
of Bladder-Based Organ Regeneration Platform for Tissue
Engineering of Esophagus." Medical Hypotheses. 78.2
pp.231-34
http://www.sciencedirect.com/science/article/pii/S03069877
11005597.
[6] “Why Have a Code of Conduct?” Ethics Resource
Center.
(2010)
(Online
Article)
http://www.ethics.org/resource/why-have-code-conduct
[6] “NSPE Code of Ethics for Engineers” National Society
of Professional Engineers. (2012)
(Online article)
http://www.nspe.org/Ethics/CodeofEthics/index.html
[7] “Biomedical Engineering Society Code of Ethics”
Biomedical Engineering Society. (2012) (Online article)
http://www.bmes.org/aws/BMES/pt/sp/ethics
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