Characterization of human dermal solutions: New raw material for tissue engineering

Abstract

Background : Tissue engineering requires scaffold for supporting tissue construction. The scaffold materials affect the scaffold properties and the achievement of tissue construction. Human skin, which is abundant of extracellular matrix, is a promising source for fabricating tissue engineering scaffolds.

Objective : To determine extracellular matrix components in human dermal solutions, and characterize fundamental physical and biological properties of the scaffolds made from the human dermal solutions.

Methods : Cadaveric human skin was prepared to be 3 fractions of dermal solutions, denoted as DS-1, DS-2 and DS-3. These dermal solutions were determined for the content of collagen and sulfated glycosaminoglycans (sulfated GAGs). Tissue engineering scaffolds were prepared form these dermal solutions and their properties were characterized comparing with scaffolds from type I collagen, commercially provided by Sigma-Aldrich corporation. The characterized physical properties included pore structure and mechanical strength and the characterized biological properties included degradation by collagenase, cell attachment and cell proliferation of human bone marrow-derived stem cells (human BMSCs).

Results : The components in each fraction of dermal solutions are obviously different. The dermal solutions contained collagen 92.23, 79.07 and 161.68 μg/mg dry weight and contained sulfated GAGs 3.09 ± 0.51, 1.36 ± 0.39 and 6.91 ± 0.87 μg/mg dry weight of DS-1, DS-2 and DS-3, respectively. The scaffolds from DS-3 had the smallest average pore size, the highest elastic modulus and the longest degradation time with significant difference (p <0.05) while those of the scaffolds from DS-1 and DS-2 are insignificantly different. The scaffolds from type I collagen (Sigma®) provided the most favorable cell attachment with significant difference (p <0.05) whereas no significant difference were found among the scaffolds from all types of human dermal solutions. The lowest cell proliferation was found in the scaffolds from DS-3 with significant difference (p <0.05). The highest cell proliferation was found in the scaffolds from DS-2, the second was the scaffolds from type I collagen (Sigma®), and the third was the scaffolds from DS-1 but no significant difference was found.

Conclusion : Human dermal solutions can be prepared from human dermis and used as raw materials for scaffold fabrication. The contents of collagen and sulfated GAGs in each type of the human dermal solutions are different, as a result, the properties of the scaffolds fabricated from each type of the human dermal solutions are also different. The scaffolds from the human dermal solutions support the proliferation of human BMSCs without any sign of cytotoxicity. Even though the scaffolds from type I collagen (Sigma®)) provided better cell attachment than all types of the scaffolds from human dermal solutions, the scaffolds from DS-2 provide better cell proliferation.