Artificial skin (tissue-engineered skin’ or ‘cultured skin graft’) allows severely damaged skin, related to burns or inherited diseases and open wounds, ability to grow new tissue, and heal faster. According to the Food and Drug Administration (2001), more than one million people are treated in the United States each year for burns. Currently, several artificial skin products provide treatment for burns and non-healing wounds. Artificial skin applied by undergoing skin grafts. However, the skin grafts are thinner, and the patient requires fewer surgeries.
Artificial skin usually consists of synthetic epidermis and collagen-based dermis (The epidermis is the outer most layer of the skin. It forms a protective wrap over the body surface or a waterproof protection. The principal cell of the epidermis is keratinocyte, and epidermis contains five layers. The deepest part of the epidermis contains melanocytes, and these cells produce melanin, which gives the skin color. The dermis (inner layer of the skin) contains blood and lymph vessels, hair follicles, and glands. The glands produce sweat, which regulate the body’s temperature and sebum, an oily substance that helps keep the skin from drying out. Through the pores, sweat and sebum reach the skin’s surface. The dermis consists of a network, of protein fibers called collagen. The network supports the growth of cells and blood vessels. Collagen replacement therapy replenishes the skin’s natural collagen.) The artificial dermis is fibers, arranged in a lattice or template, for producing new tissue. Fibroblasts (“secrete collagen proteins that are used to maintain a structural framework for many tissues”), blood vessels, nerves fibers, and lymph vessels, surrounding healthy tissue and cross into the collagen lattice, which eventually degrades, as the cells and structure build a new dermis. During the process, the synthetic epidermis becomes a temporary barrier, and eventually is replaced with a split-thickness autograft (Skin grafting obtained, from another area of the patient’s body, where undamaged skin is available. Split-thickness skin graft takes the epidermis and little of the dermis (both layers of the skin) and heals usually within several days.) This procedure is successful when the wounded area is not deep, so that the blood vessels will nourish the grafted tissue from the dermis or reproduced in the laboratory. Epidermis is cultured from the patient’s epithelial cells (help protect or enclose organs). Advanced Tissue Sciences Incorporated (San Diego California) produces TransCyte, which contains the cells fibrolasts, which help reconstruct the dermis. The British firm Smith & Nephew took over the production of Advanced Tissue Sciences, after the company filed bankruptcy protection.
In 1997, Integra Life Sciences Corporation (New Jersey), received US Food and Drug Administration, approved Integra Artificial Skin. The artificial skin is composed of a template of pure collagen (protein) fibers, from cows and glycosaminoglycan (a natural component of human skin), made from shark cartilage. After, an area of burned or scar skin is removed, a template is placed. Blood vessels and Demerol skin cells start to re-grow into new skin layer. Temporarily, silicone is added to close the outer layer, which prevents infection, controls fluid and heat loss. After 14 to 21 days, new dermal skin is produced and the silicone layer can be removed. The conclusion of the procedure still requires, a thin skin graft of the person’s epidermis. Compared to traditional skin grafting, this procedure provides more smooth surface skin, evenly healed site, dermis is regenerated, which grows as the patient grows, and pliable skin. In 1998, eighteen country members of the European Union approved Integra Artificial Skin to be marketed, for use in reconstructive surgery, and full thickness injuries. In 1999, Johnson & Johnson and Integra Life Sciences Corporation announced a strategic alliance. According to the agreement, gave Johnson & Johnson exclusive marketing and distributions rights for Integra Artificial Skin, including sales in Japan. According to Stuart E. Essig, President and Chief Executive Officer of Intergra Life Sciences: “This artificial skin is already used to treat one out of every ten severely burned patients, in the United State and top selling skin substitute in the world.”
In 2001, United States Food and Drug administration approved Dermagraft (Manufactured by Advance Tissue Sciences and Smith & Nephew), which is a dissolvable mesh material that contains human connective tissue cells (fibroblasts). Demagraft is placed directly on foot ulcers (This condition is prevalent in people that have diabetes), where the mess and fibroblasts are gradually absorbed. The fibroblasts produce protein, and growth factors found in healthy skin. During the process, damaged tissue in the foot ulcer, is replaced with healthy tissue Demagraft.
In February 2001, The Food and Drug Administration approved a new type of artificial skin, which helps children with an inherited skin disease, causes skin to become blistered by the slightest touch (epidermolysis bullosa). Eventually the hand scars meld together like a mitten. The disease or hand deformity called “dystrophic EB,” about 4,000 people a year diagnosed. Ortec Composite Cultured Skin, made by New York Ortec International. The artificial skin is made of living skin cells, grown in laboratory dishes, using newborn foreskin from cucumcisions. Added to each laboratory dish is cow collagen. Previous studies had shown successful results, applying this engineered skin. The cost: $1,000 – $5,000 depending on the severity of the disease.
Organogenesis Company, Canton Massachusetts, developed artificial made skin, from the cells of infant foreskin, called Apligraf. A Boston hospital provides the company with sample infant foreskin. The samples are broken down into their cellular components, were those cells are seeded into a petri dish, filled with bovine collagen. The cells grow in cell banks. A single infant foreskin sample produces 200,000 skin samples of Apligraf. Approximately, three weeks later, the human equivalent skin is teased out of the petri dish. Afterwards, manufactured human skin is send to Canada to be sold. Canada is the first country, which approved and certified, marketing of this engineered artificial skin. Novartis Pharmaceuticals – biotechnology unit is licensed to market the skin product in Canada. Since April 2005 – 2006, Apligraf has been used for commercial use, in about 200 people. According to Organogenesis, in Canada approximately 150,000 people, with open wounds, such as venous ulcers and burns, can benefit from Apligraf. Major advantage of Apiligraf, no rejection and no imuno-suppression required.
