Quantitative results of the analysis of novel biomaterials corresponding to the work "Generation of novel blue natural biomaterials from fish scales for use in cornea repair and engineering"

In the present work, we have evaluated four types of biomaterials generated from the scales of different species of fish, as potential biomaterials (FSB) for use in corneal repair and tissue engineering. Scales were obtained from the red scorpionfish (SSC), salmon (SSA), white sea bream (DS) and European carp (CC). Native FSB were preconditioned and cellularized with limbal epithelial cells, and evaluated ex vivo and in vivo. Results showed that FSB consisted of well-arranged layers of material and showed high levels of transparency, as revealed by high diffuse transmittance and low reflectance, scattering and absorption coefficients, and proper biomechanical properties, and these properties were preserved after preconditioning. Then, we found that FSB were biocompatible in vivo, and subcutaneous grafting in laboratory animals was not associated with a pathological local or systemic reaction, especially in CC-FSB. After recellularization, FSB supported cell attachment, proliferation and differentiation, with positive expression of limbal epithelial cell markers, and very good optical properties, with the lowest levels of scattering and absorption found in CC-FSB. Intracorneal implant of CC-FSB in laboratory rabbits demonstrated that this biomaterial was also biocompatible to the native cornea, and corneas grafted with CC-FSB had normal expression of corneal epithelium and stromal markers, such as cytokeratin 3, crystallin alpha-A, p63, collagen, proteoglycans and lumican, and devoid of any detectable signs of rejection, inflammation or neovascularization. These results suggest that CC-FSB may fulfill the requirements of biomaterials intended for use in corneal repair and regeneration, and could have potential usefulness in cornea tissue engineering.