B2
6107
Disclaimer — This paper partially fulfills a writing requirement for first year (freshman) engineering students at the
University of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper is
based on publicly available information and may not be provide complete analyses of all relevant data. If this paper is used
for any purpose other than these authors’ partial fulfillment of a writing requirement for first year (freshman) engineering
students at the University of Pittsburgh Swanson School of Engineering, the user does so at his or her own risk.
ELECTROPORATING TARGET PROGENITOR CELLS FOR BONE
REGENERATION
Rajat Lahiri (rkl14@pitt.edu, Mahboobin 10:00), Rahul Ramanathan (rar122@pitt.edu, Vidic 2:00)
Revised Proposal — Traditionally, broken bones have been
allowed to undergo osteogenesis naturally; however, many
efforts have recently gone underway to expedite the bone
regeneration process. The use of in-vivo gene therapy to
facilitate more efficient osteogenesis has received much
attention, and there have been much experimentation
involving different combinations of vectors and genes to find
the optimal rate at which bone can heal [1]. Progenitor
cells, which are young stem cells that differentiate according
to their surroundings, hold promise for being the ideal tool
for expediting bone regeneration with the help of the BMP-9
gene involved in osteogenesis [2].
Viral vectors have been very successful in the past for
transferring genes into target cells; however, there is
potential for undesired complications. Because of the
infectious nature of viruses, they can affect cells that are not
aligned with the target. The viruses engineered to inject the
desired gene into target cells could trigger an immune
response from the host, leading to “inflammation and, in
severe cases, organ failure” [3]. Due to the high probability
for error that accompanies viral vectors, electroporation has
recently been a preferred method of transfection. In the
particular case of expediting osteogenesis, target progenitor
cells in the site of the fracture can be electroporated,
allowing the BMP-9 gene to be directly transfected into the
cells. This process has yielded excellent results, improving
bone regeneration efficiency significantly and allowing for
the “complete healing of the bone defect 5 weeks following
gene delivery” [2].
The Centers for Disease Control and Prevention report
that 3.9 million visits to the emergency department are
primarily due to fractures [4]. Most of the time, fractures
are left to heal without direct medical interference, but now
lies the prospect of using progenitor cells to improve
regenerative efficiency. Electroporating target progenitor
cells are a viable method for transferring desired genes invivo. It is a method that can mediate one of the most
widespread problems in the population. This new method of
expediting bone regeneration can prove to be life-changing
for those who suffer from acute as well as chronic bone
fractures.
This paper will primarily focus on the stated method for
accelerating the bone healing process, but will also discuss
current procedures as well. Essentially, we will explore the
University of Pittsburgh, Swanson School of Engineering 1
2016/01/29
benefits of using progenitor cells as opposed to other
contemporary solutions. By the end of the paper, we plan to
establish the effectiveness of our technology and its future
applicability in medicine. We will present our paper by
introducing the nature of fractures, exploring current
treatments, analyzing the progenitor cell method, and finally
assessing the true efficacy of this particular approach. Our
plan of research includes reporting results of scientific
studies geared towards finding the optimum combination of
vectors and genes to maximize the rate of bone regeneration.
REFERENCES
[1] C. Evans. (2011, March 17). “Gene therapy for the
regeneration of bone.” Center for Advanced Orthopaedic
Studies.
(Online
article).
http://www.sciencedirect.com/science/article/pii/S00201383
1100126
[2] N. K. Bleich, I. Kallai, J. R. Lieberman, E. M. Schwarz,
G. Pelled, D. Gazit. (2011, October 25). “Gene therapy
approaches to regenerating bone.” Advanced Drug Delivery
Reviews.
(Online
article).
http://www.sciencedirect.com/science/article/pii/S0169409X
12001032
[3] “Risks.” Mayo Clinic. (2013, January 15). (Online
article). http://www.mayoclinic.org/tests-procedures/genetherapy/basics/risks/prc-20014778
[4] CDC. (2010). “National Hospital Ambulatory Medical
Care Survey: 2010 Emergency Department Summary
Tables.” National Hospital Ambulatory Medical Care
Survey.
(Online
report).
http://www.cdc.gov/nchs/data/ahcd/nhamcs_emergency/201
0_ed_web_tables.pdf
ANNOTATED BIBLIOGRAPHY
N. K. Bleich, I. Kallai, J. R. Lieberman, E. M. Schwarz, G.
Pelled, D. Gazit. (2011, October 25). “Gene therapy
approaches to regenerating bone.” Advanced Drug Delivery
Reviews.
(Online
article).
http://www.sciencedirect.com/science/article/pii/S0169409X
12001032
Rajat Lahiri
Rahul Ramanathan
K. E. Hanna. (2006, March). “Germline Gene Transfer.”
National Human Genome Research Institute. (Online
article). http://www.genome.gov/10004764
This professional article from the National Human
Genome Research Institute contains information on the
scientific issues with germline gene transfer, the ethical
concerns of gene transfers, and the government regulation
and policy over gene therapy. This article explains how
current procedures of gene therapy have negative
consequences that can be mitigated through gene
modification. This article provides the necessary data to
address ethical issues.
Bleich and his co-authors assess the possible
complications with the procedure of using progenitor cells
and gene therapy to expedite bone regeneration. Specifically,
the article contains important information regarding the
pituitary gland’s hyper-production of growth factor hormone
when stimulated by the BMP-gene located in progenitor
cells. This is crucial to our study, as it is important that we
assess the possible negative effects of the bone regeneration
procedure.
CDC. (2010). “National Hospital Ambulatory Medical Care
Survey: 2010 Emergency Department Summary Tables.”
National Hospital Ambulatory Medical Care Survey. (Online
report).
http://www.cdc.gov/nchs/data/ahcd/nhamcs_emergency/201
0_ed_web_tables.pdf
This report, from the governmental agency of the Center
of Disease Control, consists of data tables regarding
emergency department visits. The data tables provide
information on various statistics on the types of visits by
various factors. We will use some of the data tables that
report on fractures and include in our paper the frequency of
fractures. This source will be used for the statistics only on
fractures.
N. Kimelman, G. Pelled, Z. Gazit, D. Gazit. (2006).
“Applications of gene therapy and adult stem cells in bone
bioengineering.” Future Medicine. (Online article).
http://www.futuremedicine.com/doi/full/10.2217/17460751.
1.4.549
This article published in the Regenerative Medicine
magazine outlines the general applicability of gene therapy
for regenerating osseous tissue. However, this article
provides a unique view, in which the author claims that it
may be more effective if the BMP-9 gene was inserted invivo directly to osseous tissue, rather than through the use of
progenitor cells. We will consider this view in our paper and
assess both the pros and cons of not using viral vectors.
C. Evans. (2011, March 17). “Gene therapy for the
regeneration of bone.” Center for Advanced Orthopaedic
Studies.
(Online
article).
http://www.sciencedirect.com/science/article/pii/S00201383
11001264
This professional article from the Injury magazine details
the importance of gene therapy and its role in orthopedic
applications. It contains valuable information on different
types of gene therapy and how they can be used to transfer
desired genes to bones. In addition, this article contains a
table which outlines the efficacy of each type of viral vector.
We will use this to assess the importance of using
electroporation to transfer the gene, rather than a viral
vector.
J. E. Phillips, C. A. Gersbach, A. J. Garcia. (2006, May 8).
“Virus-based gene therapy strategies for bone regeneration.”
Petit Institute for Bioengineering and Biosciences. (Online
article).
http://www.sciencedirect.com/science/article/pii/S01429612
06006557
This article published in the Biomaterials Journal
assesses the efficacy of different methods of gene therapy on
bone regeneration. The author makes the important claim
that progenitor cells hold promise for being an efficient way
to heal bone. We will use this information in our paper to
outline the pros and cons of using human progenitor cells to
expedite the bone healing process.
C. H. Evans. (2014, September). “Using Genes to Facilitate
the Endogenous Repair and Regeneration of Orthopaedic
Tissues.” International Orthopaedics. (Online article).
http://doi.org/10.1007/s00264-014-2423-x
This article, from a professional journal detailing
advancements in orthopaedics, explains how traditional
tissue engineering methods can be replaced with gene
transfer technology. The article describes new gene transfer
techniques that can expedite bone regeneration and optimize
bone regeneration. It includes preclinical experiment data in
animal models that may be applied to human medicine. We
will use this article to report on new methods that could help
with bone regeneration.
“Risks.” Mayo Clinic. (2013, January 15). (Online article).
http://www.mayoclinic.org/tests-procedures/genetherapy/basics/risks/prc-20014778
This article, from a nonprofit medical group practice,
contains an overview of the risks caused by gene therapy.
This article provides a generalized description of the risks
and the results from gene therapy. We will need this source
for our paper to understand the negative consequences of
gene therapy, and then relate as to whether our method of
bone regeneration can cause these same issues.
2