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Tissue-engineered skin is a significant advance in the field of wound healing and was developed due to limitations associated with the use of autografts. These limitations include the creation of a donor site which is at risk of developing pain, scarring, infection and/or slow healing. A number of products are commercially available and many others are in development. Cultured epidermal autografts can provide permanent coverage of large area from a skin biopsy. However, 3 weeks are needed for graft cultivation. Cultured epidermal allografts are available immediately and no biopsy is necessary. They can be cryopreserved and banked, but are not currently commercially available. A nonliving allogeneic acellular dermal matrix with intact basement membrane complex (Alloderm) is immunologically inert. It prepares the wound bed for grafting allowing improved cultured allograft 'take' and provides an intact basement membrane. A nonliving extracellular matrix of collagen and chondroitin-6-sulfate with silicone backing (Integra) serves to generate neodermis. A collagen and glycosaminoglycan dermal matrix inoculated with autologous fibroblasts and keratinocytes has been investigated but is not commercially available. It requires 3 to 4 weeks for cultivation. Dermagraft consists of living allogeneic dermal fibroblasts grown on degradable scaffold. It has good resistance to tearing. An extracellular matrix generated by allogeneic human dermal fibroblasts (TransCyte) serves as a matrix for neodermis generation. Apligraf is a living allogeneic bilayered construct containing keratinocytes, fibroblasts and bovine type I collagen. It can be used on an outpatient basis and avoids the need for a donor site wound. Another living skin equivalent, composite cultured skin (OrCel), consists of allogeneic fibroblasts and keratinocytes seeded on opposite sides of bilayered matrix of bovine collagen. There are limited clinical data available for this product, but large clinical trials are ongoing. Limited data are also available for 2 types of dressing material derived from pigs: porcine small intestinal submucosa acellular collagen matrix (Oasis) and an acellular xenogeneic collagen matrix (E-Z-Derm). Both products have a long shelf life. Other novel skin substitutes are being investigated. The potential risks and benefits of using tissue-engineered skin need to be further evaluated in clinical trials but it is obvious that they offer a new option for the treatment of wounds.

Background: At present, wound treatment of inherited epidermolysis bullosa (EB) is only supportive.Objective: To determine the safety and clinical effects of tissue-engineered skin (Apligraf; Organogenesis Inc, Canton, Mass) in the healing of wounds of patients with different types of EB.Design: An open-label uncontrolled study of 15 patients with EB treated with tissue-engineered skin. Each patient received tissue-engineered skin on up to 2 wounds on each of 3 clinic visits: day 1, week 6, and week 12. They were evaluated 7 ( ± 3) days and 6 weeks after each round of treatment. A quality-of-life survey was administered during week 6.

Debridement can play a vital role in wound bed preparation and the removal of barriers that impair wound healing. In accordance with the TIME principles, debridement can help remove nonviable tissue, control inflammation or infection, decrease excess moisture, and stimulate a nonadvancing wound edge. There are many types of debridement, each with a set of advantages and disadvantages that must be clearly understood by the healthcare team. Failure to use the correct debridement method for a given type of wound may lead to further delays in healing, increase patient suffering, and unnecessarily increase the cost of care. This review article discusses the various methods of debridement, describes currently available debriding agents, evaluates the clinical data regarding their efficacy and safety, and describes strategies for the management of problematic nonhealing wounds.

No longer an option of last resort, skin grafting has become a technique that is routinely and sometimes preferentially considered as skin replacement for burns, chronic ulcers, and skin defects after cutaneous surgical procedures. When selected as the best alternative for wound closure, autologous skin grafts are commonly considered the gold standard. Availability of autologous grafts is a major obstacle, however, and the search for a manufactured skin replacement has continued. In cases in which autologous grafts cannot be performed, skin substitutes have become an attractive alternative.

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There is evidence that anabolic steroids, which are derived from testosterone and have markedly less androgenic activity, promote tissue growth and enhance tissue repair; however, the mechanisms involved in their anabolic activities remain unclear. In this report, we measured the effect of the anabolic steroid stanozolol on cell replication and collagen synthesis in cultures of adult human dermal fibroblasts. Stanozolol (0.625-5 microg per ml) had no effect on fibroblast replication and cell viability (p = 0.764) but enhanced collagen synthesis (p < 0.01) in a dose-dependent manner (r = 0.907). Stanozolol also increased (by 2-fold) the mRNA levels of alpha1 (I) and alpha1 (III) procollagen and, to a similar extent, upregulated transforming growth factor-beta1 (TGF-beta1) mRNA and peptide levels (p < 0.001). There was no stimulation of collagen synthesis by testosterone. The stimulatory effects of stanozolol on collagen synthesis were blocked by a TGF-beta1 anti-sense oligonucleotide, by antibodies to TGF-beta, and in dermal fibroblast cultures derived from TGF-beta1 knockout mice. We conclude that collagen synthesis is increased by the anabolic steroid stanozolol and that, for the most part, this effect is due to TGF-beta1. These findings point to a novel mechanism of action of anabolic steroids.

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