Transcript Tissue Engineering of the Skin

BURN TREATMENT
AND TISSUE
ENGINEERING OF THE
SKIN
Presentation By:
Cara Nunez
BACKGROUND
 Skin:
 Epidermis
 Dermis
 Hypodermis/Subcutaneous
Layer
 Functions of the Skin:
 1. Protect the body
 2. Sensation
 3. Heat Regulation
 4. Control of Evaporation
 5. Absorption
 6. Water resistance
 7. Storage/Synthesis
 8. Aesthetics/Communication
BURNS
 Burns are generally classified by depth
 The time they take to heal are directly related to the
depth of the burn
 1st and minor 2nd degree burns are painful
 Serious 2nd degree and 3rd degree burns do not hurt
because the nerve endings are destroyed
BURNS (CONT.)
1st Degree
Only epidermis
Healing time is 1 week or less
2nd Degree
Epidermis + Dermis
Healing time – several weeks, deeper burns take longer
3rd Degree
Epidermis, Dermis and Subcutaneous layers
Healing time – many weeks, usually requires excision
and grafting and can cause complications including
amputation and loss of life
HISTORY OF BURN TREATMENT
 The overall goal of burn treatment is to fully heal the
skin with minimal scarring and full functionality, while
also managing the patient's pain
 Mankind has been trying to heal burns since the discovery of
fire
 Ebers Papyrus (1500 BC) lists a mixture of cattle
dung and black mud as “just what the doctor
ordered” for burns
HISTORY (CONT.)
 For many years there was very little consensus on how
to treat burns
 Fabricius Hildanus, a German Physician, first classified
burns into three degrees in the 1600's
 After World War I the preferred treatment was surgical
skin transplantation → Less scarring than before
HISTORY (CONT.)
 Wide use of firebombs in
the Korean war of the
1950's
 The U.S. Army Burn Center
in San Antonio, Texas makes
it a standard to skin graft
patients with 30% or more
total body surface area
burns
HISTORY (CONT.)
 The new standard of
treatment became to excise
the necrotic tissue and replace
it with grafts of healthy skin,
usually taken from the patient's
legs
 This is effective, but the patient
is still disfigured, covered in
scars and can suffer from
chronic life long pain
CONVENTIONAL WESTERN BURN TREATMENT
 In many cases grafting is not
possible because there simply is
not enough healthy skin left
 Doctors have been able to
culture and grow skin since the
1970's
 These sheets of skin are
extremely fragile and take weeks
to grow – precious time in which
a patient can develop an infection
and die
HOLISTIC TREATMENT
 Professor Xu Rong Xiang of
China
 introduced a new, holistic method
of burn treatment in the 1970's
 “Moist Exposed Burns
Treatment” (MEBT)
 “Moist Exposed Burns Ointment”
(MEBO) [patented]
 No surgical excision!
TISSUE ENGINEERING OF THE SKIN
 Tissue engineering of the skin is a combination of all of this
 Skin grafting was an innovative method when it was first
implemented
 Tissue engineering is starting to be the bridge between the
conventional methods of burn treatment and Xiang's holistic
method
CURRENT METHODS
Conventional:
 Work to improve methods for
growing cultured skin
 Specialized scaffolds can be used
to support more complex/thick
layers of epidermal cells
 This is called ex-vivo skin growth
Pros:
Highly effective for 2nd degree
burns
The skin is the patient’s own and
does not need to be taken from
another body site
Cons:
As of now, this method still leaves
major scarring
This method cannot regenerate
destroyed nerve endings
CURRENT METHODS (CONT.)
Holistic Method:
 Using MEBO allows for
regeneration of the tissue
 This area of research is
quickly moving towards
stem cells as a method
allowing more natural skin
regrowth
Pros:
The skin that regrows will have
less scarring than grafted skin
Cons:
This technique is not as tried
and tested as skin grafting however, it is more widely used
in China and has shown great
success in clinical trials there
THE FUTURE OF SKIN TISSUE ENGINEERING
 A suspension of the
patients own skin stem
cells can be evenly sprayed
like paint onto the burn
 This technology is still
being tested but seems
very promising
RESOURCES
 Bianco, Paolo, and Pamela Robey. "Stem Cells in Tissue Engineering." NATURE.
Macmillan Magazines Ltd, 1 Nov. 2001. Web. 13 Oct. 2012.
<http://users.isr.ist.utl.pt/~sm3/biomedica/tissue-engeneering/Tiss_eng_2.pdf>.
 Gallico, MD, Gregory, Nicholas E. O'Connor, MD, Carolyn Compton, MD, and Olaniyi
Kehinde, B.A. "Permanent Coverage of Large Burn Wounds with Autologous Cultured
Human Epithelium." The New England Journal of Medicine (1984): 448-51. Print.
 "Glossary about MEBT/MEBO." Glossary about MEBT/MEBO. China Herb Store, n.d.
Web. 13 Oct. 2012. <http://www.chinaherbstore.com/MEBO/glossary-about-mebtmebo.html>.
 Horch, Raymond E. "Future Perspectives in Tissue Engineering." Journal of Cellular and
Molecular Medicine (2007). Print.
RESOURCES (CONT.)
 Pomahac, and Svensio. "Tissue Engineering of Skin." Division of Plastic Surgery,
Brighom/Children's/Harvard, 1998. Web. 13 Oct. 2012.
<http://filebox.vt.edu/p/pomur/skin%20engineering.pdf>.
 "Video -- The Skin Gun -- National Geographic." Video -- National Geographic. National
Geographic. Web. 13 Oct. 2012. <http://video.nationalgeographic.com/video/nationalgeographic-channel/shows/explorer-1/ngc-the-skin-gun/>.
 Weeks, MD, Bradford S. "Brief Introduction to the History of Burns Medical Science."
Burns Regenerative Medicine and Therapy (2000). Karger.com. 2000. Web. 13 Oct. 2012.
<http://content.karger.com/ProdukteDB/Katalogteile/isbn3_8055/_76/_61/Burns_Intr
o.pdf>.