Development of microstructured fish scale collagen scaffolds to manufacture a tissue-engineered oral mucosa equivalent

The present study aimed to develop a more biomimetic tissue-engineered oral mucosa equivalent comprising 1% type I tilapia scale collagen scaffold having microstructures mimicking the dermal–epidermal junction of oral mucosa and oral keratinocytes as graft materials for human use. We designed four micropattern prototypes mimicking the dermal–epidermal junction. Using a semiconductor process and soft lithography, negative molds were fabricated to develop microstructures using both polydimethylsiloxane and silicon substrates. Micropattern configurations of dermal–epidermal junctions manufactured from fish collagen consisting of a fibril network using our micropatterning system were well preserved, although the internal fibril network of the pillar pattern was sparse. Mixing 1% chondroitin sulfate with the collagen matrix minimized tissue-engineered oral mucosa equivalent contraction. Histologic examinations showed a flattening of the vertical dimensions of all microstructures and expansion of their pitches, indicating changes in the originally designed configurations. Nonetheless, histologic examinations revealed that a fully differentiated and stratified epithelial layer was developed on all scaffolds, suggesting that the microstructured fish scale collagen scaffolds have potential in the manufacturing of tissue-engineered oral mucosa equivalents for clinical use; however, enhancement of the mechanical properties of micropatterns is required. Our micropatterning technology can also apply to the development of oral mucosa in vitro models.