Decellularized scaffolds can serve as an excellent three-dimensional environment for cell repopulation. They maintain tissue-specific microarchitecture of extracellular matrix proteins with important spatial cues for cell adhesion, migration, growth, and differentiation. However, criteria for quality assessment of the three-dimensional structure of decellularized scaffolds are rather fragmented, usually study-specific, and mostly semi-quantitative. Thus, we aimed to develop a robust structural assessment system for decellularized porcine liver scaffolds. Five scaffolds of different quality were used to establish the new evaluation system. We combined conventional semi-quantitative scoring criteria with a quantitative scaffold evaluation based on automated image analysis. For the quantitation, we developed a specific open source software tool (ScaffAn) applying algorithms designed for texture analysis, segmentation, and skeletonization. ScaffAn calculates selected parameters characterizing structural features of porcine liver scaffolds such as the sinusoidal network. After evaluating individual scaffolds, the total scores predicted scaffold interaction with cells in terms of cell adhesion. Higher scores corresponded to higher numbers of cells attached to the scaffolds. Moreover, our analysis revealed that the conventional system could not identify fine differences between good quality scaffolds while the additional use of ScaffAn allowed discrimination. This led us to the conclusion that only using the combined score resulted in the best discrimination between different quality scaffolds. Overall, our newly defined evaluation system has the potential to select the liver scaffolds most suitable for recellularization, and can represent a step toward better success in liver tissue engineering.

Biomedical Center Faculty of Medicine in Pilsen Charles University Prague Pilsen Czech Republic

Centre for Electron Microscopy University Hospital Jena Jena Germany

Department of Biophysics Faculty of Medicine in Pilsen Charles University Prague Pilsen Czech Republic

Department of Cybernetics University of West Bohemia Pilsen Czech Republic

Department of Pathology 3rd Faculty of Medicine Charles University Prague Prague Czech Republic

Department of Surgery Faculty of Medicine in Pilsen Charles University Prague Pilsen Czech Republic

Department of Toxicogenomics National Institute of Public Health Prague Czech Republic

Experimental Transplantation Surgery Department of General Visceral and Vascular Surgery University Hospital Jena Jena Germany

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Decellularization of Porcine Carotid Arteries: From the Vessel to the High-Quality Scaffold in Five Hours

Semantic Segmentation of Intralobular and Extralobular Tissue from Liver Scaffold H&E Images