Keratinocyte-fibroblast Cocultures on A Bi-layered Gelatin Scaffold for Skin Equivalent Tissue Engineering

The skin is composed of three parts: epidermis, dermis and subcutaneous fatty layers. In order to develop a biomimetic material for more realistic tissue regeneration, we fabricated a bi-layered gelatin sponge with different pore sizes by freeze-drying at different temperatures -20 < degrees >C and -196 < degrees >C, respectively. A rete ridges-like topographic microporous structure, which provided the paracrine crosstalk in epithelial-mesenchymal interactions similar to the basement membrane in epidermal-dermal junction, was formed between these two compartments. Chrondroitin-6-Sulphate (C-6-S) and hyaluronic acid (HA) were incorporated within the gelatin scaffold to create an appropriate microenvironment for cell proliferation and migration. The mechanical strength of gelatin sponges was improved by cross-linking of gelatin with 1-ethyl-3 (3-dimethyl aminopropryl) carbodiimide (EDC). The lattice structure and pore sizes were evaluated by SEM to confirm the interconnected porous structures retained. We chose a dynamic spinner flask seeding method for more evenly distribution followed by a culture system in the air-liquid interface and cultured for 21 days. Differentiation and phenotypic expression of keratinocytes were investigated by histological analysis. In this study, we found a multiple epidermis-like layers constructed by cultured keratinocytes. It is suggested that the bi-layered scaffolds have the potential to be used as skin equivalents for the application in burn patients. In the future, the in vivo animal model tests will be evaluated.

In vitro test approach

2003 J MED BIOL ENG. Journal of Medical and Biological Engineering 2003 ;23 (4):213-219
F.-H. Lin, Grad. Inst. of Biomed. Engineering, College of Medicine, National Taiwan University, Taipei, 100 EML: [email protected]