Tissue Engineered Skin Substitutes

Abstract

The fundamental skin role is to supply a supportive barrier to protect body against harmful agents and injuries. Three layers of skin including epidermis, dermis and hypodermis form a sophisticated tissue composed of extracellular matrix (ECM) mainly made of collagens and glycosaminoglycans (GAGs) as a scaffold, different cell types such as keratinocytes, fibroblasts and functional cells embedded in the ECM. When the skin is injured, depends on its severity, the majority of mentioned components are recruited to wound regeneration. Additionally, different growth factors like fibroblast growth factor (FGF), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF) are needed to orchestrated wound healing process. In case of large surface area wounds, natural wound repair seems inefficient. Inspired by nature, scientists in tissue engineering field attempt to engineered constructs mimicking natural healing process to promote skin restoration in untreatable injuries. There are three main types of commercially available engineered skin substitutes including epidermal, dermal, and dermoepidermal. Each of them could be composed of scaffold, desired cell types or growth factors. These substitutes could have autologous, allogeneic, or xenogeneic origin. Moreover, they may be cellular or acellular. They are used to accelerate wound healing and recover normal skin functions with pain relief. Although there are a wide variety of commercially available skin substitutes, almost none of them considered as an ideal equivalents required for proper wound healing.

Proteins and Peptides as Important Modifiers of the Polymer Scaffolds for Tissue Engineering Applications—A Review

“…It constitutes a protective barrier towards outer world, and thus is susceptible to damage resulting from inter alia burns, surgical procedures, or diabetic ulcers. To enhance wound repair and regeneration, many tissue-engineered skin products have been developed [232][233][234][235][236]. In general, biomaterials for treatment of skin injuries can be divided on two groups including wound dressings and skin substitutes ( Table 1).…”

“…In other words, they should have optimal water vapor transmission ratio (WVTR) and great ability to absorb wound exudate (if it occurs). Moreover, modern wound dressings should also accelerate wound healing [232][233][234]236,[242][243][244][245]. Progress in the field of engineering of biomaterials has led to the development of many promising wound dressings.…”

“…Skin substitutes should also possess mechanical parameters close to those of natural skin (inter alia Young's modulus. ranging 60-850 kPa) [232][233][234]236,[242][243][244][245]248]. Nowadays, there is no biomaterial that meets all these criteria.…”

Regeneración Del Órgano Cutáneo Mediante Ingeniería De Tejidos

“…La piel es la primera línea de defensa contra el medio exterior y además ayuda a mantener la termorregulación del cuerpo humano [8]. Es elórgano más grande, el más externo y actúa como una envoltura del cuerpo, lo cual, consecuentemente, hace que sea eĺ organo más propenso a herirse.…”

<p>Autologous Fat Grafting Promotes Macrophage Infiltration to Increase Secretion of Growth Factors and Revascularization, Thereby Treating Diabetic Rat Skin Defect</p>

“…[4][5][6] However, limited self-renewal ability of skin in severe chronic diabetic wounds necessitates the use of different skin grafting methods like full-thickness skin grafting including the whole dermis and epidermis. 7,8 As chronic diabetic wounds have more necrotic tissues and ischemia, patients usually need to suffer a long process of skin debridement and the skin cannot be directly grafted. 9 Except for the difficulty of flap transplantation which requiring experienced surgeons, diabetic patients are still at risk of failure due to vascular disease.…”