3d bioprinting graft scaffolds a base di fibroina della seta per applicazione clinica di rigenerazione tissutale

Firstly, we performed a double-energy CT scan (CT-DE) of anatomical pieces from cadavers (bones and soft tissues) to define the radiological parameters, that were necessary to subsequent move on the patient. Subsequently, the best ratio between delivered radiant dose and image quality was analyzed and dose reduction systems (VEO and ASIR) and metal artefacts reduction systems (GSI and MAR) were evaluated. The VEO system allowed an optimal evaluation of the bone tissue with a dose reduction of over 50% compared to the ASIR system; with the GSI system we have identified the mono-energy levels that better reduced artifacts from metal prosthesis and that were used with MAR software to reduce post-processing artifacts. The images were imported in DICOM format in a dedicated software for their visualization, segmentation and processing to reproduce the anatomy of the bone tissue. The printing of 3D scaffolds that reproduced the original tissue was done using a Bioplotter. The silk fibroin Bioink was used to prepare the scaffold and, to define the architecture of interest. All the printing parameters were optimized. The Bioink were prepared both without calcium (SFG) or with calcium chloride (SFG-CaCl2). Mesenchymal cells (MSCs) were incorporated into the bioinks and we observed that in both bioinks the cells were homogeneously distributed and viable at all experimental times (day 1, 7, 14, 21) analyzed. Using specific osteogenic factors (FO), in both bioinks MSCs osteogenic differentiation was induced. In particular, in the presence of FO, we found an increase in mineralization in SFG-CaCl2 bioink compared to that obtained in SFG bioink. Moreover, in the absence of FO only in the bioink SFG-CaCl2 the presence of calcium precipitates were noted indicating that the osteogenic differentiation occured.