Biomedical Engineering Reference
In-Depth Information
The wide use of biomaterials incorporated into surgical procedures has increased the
rate of surgical infections. Approximately 15% of the 2.4 million hospital-acquired infec-
tions each year in the United States are surgical-site infections [58]. To avoid this, the use
of antimicrobial factors within biomaterials can be used. When incorporated into nano-
fibers, antimicrobial factors can help to prevent the formation of bacterial biofilms by
releasing an agent to kill or inhibit the growth, thus reducing the potential of surgical site
infections [12, 54].
Growth factors in nanofibers aid in stem-cell proliferation and guide cells to differentiate
into the desired phenotype. In addition, growth factors can affect the cell behavior due to
their ability to bind specific cell-surface receptors, which can trigger a cascade of molecular
events. The best characterized growth factors in wound healing are those from the epidermal
growth factor (EGF) family: such as EGF, heparin binding EGF (HB-EGF), transforming
growth factor-alpha (TGF-α), epiregulin, amphiregulin, betacellulin, epigen, neuregulin-1
(NRG-1), NRG-2, NRG-3, NRG-4, NRG-5, and NRG-6 [59].
Conclusion and Future Outlooks
Successful skin regeneration is a restorative option that could overcome the drawbacks
involved in current wound-repair and skin-replacement techniques. Understanding the
biology of wound repair is essential for the improvement of skin regeneration and though
science has made strides in the past century, the understanding of the microenvironments
within successful skin regeneration is key. These microenvironmental cues are what dictate
stem-cell function in both healthy and diseased states [8] . Early progress was made to clarify
such skin compartments, but a detailed understanding of their molecular and structural
biology remains incomplete. The biomaterial involved in the regeneration process will con-
tinue to play a central role by providing the framework upon which to reconstruct the skin
environment. The future challenges will include being able to capture and recreate the
dynamic microenvironments using engineered constructs in order to take full advantage of
the regenerative potential of stem cells.
Acknowledgment
The authors gratefully acknowledge funding from The Raymond and Beverly Sackler Center
for Biomedical, Biological, Physical and Engineering Sciences. Authors also acknowledge
funding from National Science Foundation Award Number IIP-1311907, IIP-1355327; and
EFRI-1332329, as well as Department of Defense (OR120140).
References
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Brodell LA and KS Rosenthal (2008). Skin structure and function: the body's primary defense
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Sen CK, GM Gordillo, S Roy, R Kirsner, L Lambert, TK Hunt, F Gottrup, GC Gurtner and MT
Longaker (2009). Human skin wounds: a major and snowballing threat to public health and the
economy. Wound Repair and Regeneration 17: 763-771.
[3]
Hwa C, EA Bauer and DE Cohen (2011). Skin biology. Dermatologic Therapy 24: 464-470.
[4]
MacNeil S (2007). Progress and opportunities for tissue-engineered skin. Nature 445: 874-880.
[5]
Singer AJ and R Clark (1999). Cutaneous wound healing. New England Journal of Medicine
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