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Eukaryon, Vol. 11, March 2015, Lake Forest College
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Dr. Frankenstein’s Ghost Heart
Rachel Hastings
Department of Biology
Lake Forest College
Lake Forest, Illinois 60045
With only four rooms and around ten ounces of weight,
it is the world’s most wondrous building. Once its doors open, it
must continue this process of opening and closing, pumping the
river of life through the veins. For it to stop is a death sentence
to the human host it resides in. The heart, this powerhouse of
life, is perhaps the most valued organ in the human body. Not
only is it powerful and mighty, it is tuned into the smallest bits
of our humanity e.g., the skipping dance it does when we see
the face of a certain someone or the racing thuds it pounds to
when we are getting ready for a presentation. It is no surprise,
then, that scientists have failed to recreate a human heart
from scratch. Texas Heart Institute’s director of regenerative
medicine research, Doris Taylor has however done something
equally impressive, she has succeeded in stripping hearts of all
that makes them unique (decellularized them) and used their
architecture to recreate a heart capable of pumping in another
beings body.
In the United States alone, 3,000 patients are awaiting
for a donor heart, nearly 5 million are living with heart failure
and there are about 550,000 new cases annually. After twelve
years, a heart transplant patient has only a 50 percent chance of
surviving. The main reason patients die after a heart transplant
is rejection.The immune system does not recognize the foreign
cells suddenly invading the body and decides it needs to protect
by attacking the transplanted organ. To prevent rejection, endomyocardial biopsies must be done. These biopsies come with
occasional risks such as hepatitis B transmissions, arrhythmias,
hematoma, and cardiac perforation. The patients must also take
immunosuppressant’s to prevent rejection. The side affects of
these medications include hypertension, renal effects, tremor,
headaches, glucose intolerance, and metabolic problems. Then
there are infections, which are common after organ transplants
because of course immunosuppressant’s are meant to prevent
the immune system from protecting the body from potentially
harmful foreign substances. There are so many problems associated with organ rejection that it can be concluded that finding a
way to get rid of the “foreignness” of an organ can substantially
increase the life expectancy of a heart transplant patient.
This is exactly what Doris Taylor and her team does
when she decellularized rat hearts. First they remove all DNA
and intracellular material using detergent solutions and evaluate the hearts afterwards to make sure no remaining nuclei remained. Only the structure of the hearts remain. The heart has
a white opaque quality resembling a ghost, hence the title “ghost
heart”. The hearts are then placed in a bioreactor and injected
with cardiac stem cells. By the eight day, the hearts began to
contract and show electrical responses. For the first time Dr.
Taylor’s team has successfully decellularized a heart and repopulate it with cells from a different individual creating a heart that
is capable of pumping.
Dr. Taylor hopes that this recreation of the rat hearts
can be extended towards human hearts Such a feat is complex
and difficult because of the many arteries and vessels that must
be grown to keep the heart alive. Dr. Taylor has succeeded however in recreating a porcine heart proving that this method can
be applied to a heart that is almost as complex and large as
the human heart. Then there is the main goal of this entire procedure, which is that these hearts will eventually be able to be
transplanted into a human being. In an environment other than
the human body, such as a bioreactor, the heart is able to pump,
but the heart needs to be able to do more than just pump once
it is transplanted into a human body. The heart needs to able
to work within a whole network of other organs and systems.
In order to function like any other heart, these ghost hearts still
need more work and experiments need to be done in vivo. Once
this procedure has been proven to work in the human body, Dr.
Taylor believes that ghost hearts can be extended towards less
complex organs such as the lungs and the liver. . Once this procedure has been proven to work in the human body, Dr. Taylor
believes that ghost hearts can be extended towards less complex organs such as the lungs and the liver.
Such a simple strategy to such a complex problem
seems almost ridiculous, yet Dr. Taylor has proven that
sometimes the best answers are the simplest ones. Using ghost
hearts in heart transplants eliminates the chance of rejection in
heart transplant patients. This will greatly increase their survival
rate and relieve the pain and suffering they endured as a result
of immunosuppressants. Ghost heart transplantation is a simple
idea that will revolutionize current heart transplant methods.
Figure 1.Perfusion decellularization of whole rat hearts. (a-c)
Photographs of cadaveric rat hearts mounted on a Langendorff
apparatus. Ao, aorta; LA, left atrium; LV, left ventricle; RA, right
atrium; RV, right ventricle. Retrograde perfusion of cadaveric rat
heart using PEG (a), Triton-X-100 (b) or SDS (c) over 12 h. The heart
becomes more translucent as cellular material is washed out from
the right ventricle, then the atria and finally the left ventricle. (d,e)
Corresponding H&E staining of thin sections from LV of rat hearts
perfused with PEG (d) or Triton-X-100 (e), showing incomplete
decellularization. Hearts treated with PEG or Triton-X-100 retained
nuclei and myofibers. Scale bars, 200 μm. (f) H&E staining of thin
section of SDS-treated heart showing no intact cells or nuclei. Scale
bar, 200 μm. All three protocols maintain large vasculature conduits
(black asterisks). (g) Immunofluorescent staining of cadaveric and
SDS-decellularized rat heart thin sections showing the presence or
absence of DAPI-positive nuclei (purple), cardiac α-myosin heavy
chain (green) or sarcomeric α-actin (red). Nuclei and contractile
proteins were not detected in decellularized constructs. Scale bars,
50 μm.
Eukaryon, Vol. 11, March 2015, Lake Forest College
Note: Eukaryon is published by students at Lake Forest
College, who are solely responsible for its content. The views
expressed in Eukaryon do not necessarily reflect those of the
College. Articles published within Eukaryon should not be cited
in bibliographies. Material contained herein should be treated as
personal communication and should be cited as such only with
the consent of the author.
References
Bianco, Carl. “How Your Heart Works” 01 April 2000. HowStuffWorks.
com. <http://health.howstuffworks.com/human-body/systems/
circulatory/heart.htm> 17 November 2014.
Maher, Brendan. (2013). Tissue engineering: How to build a heart.
Nature, 499(7456), 20-22.doi:10.1038/499020a
Ott, H. C., Matthiesen, T. S., Goh, S., Black, L. D., Kren, S. M., Netoff,
T. I., & Taylor, D. A. (2008). Perfusion-decellularized matrix:
using nature’s platform to engineer a bioartificial heart. Nature
Medicine, 14(2), 213-221. doi:10.1038/nm1684
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