BURN TREATMENT AND TISSUE ENGINEERING OF THE SKIN

1. BURN TREATMENT AND TISSUE ENGINEERING OF THE SKIN Presentation By: Cara Nunez

2. 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

3. 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

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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!

11. 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

12. 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

13. 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

14. 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

15. 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-mebt-mebo.html>. • Horch, Raymond E. "Future Perspectives in Tissue Engineering." Journal of Cellular and Molecular Medicine (2007). Print.

16. 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/national-geographic-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_Intro.pdf>.