Biomaterials
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Pancreatic islet encapsulation within biosynthetic materials has had limited clinical success due to loss of islet function and cell death. As an alternative encapsulation material, a silk-based scaffold was developed to reestablish the islet microenvironment lost during cell isolation. Islets were encapsulated with ECM proteins (laminin and collagen IV) and mesenchymal stromal cells (MSCs), known to have immunomodulatory properties or to enhance islet cell graft survival and function. ⋯ A 3.2-fold synergistic improvement in islet insulin secretion was observed when islets were co-encapsulated with MSCs and ECM proteins. Furthermore, encapsulated islets had increased gene expression of functional genes; insulin I, insulin II, glucagon, somatostatin, and PDX-1, and lower expression of the de-differentiation genes cytokeratin 19 and vimentin compared to non-encapsulated cells. This work demonstrates that encapsulation in silk with both MSCs and ECM proteins enhances islet function and with further development may have potential as a suitable platform for islet delivery in vivo.
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Epidural fibrosis resulted from epidural fat destruction following laminectomy operation is regarded as a main cause of failed back surgery syndrome, which represents one of the most common complications in spine surgery. Up to now, the effectiveness of currently available treatments to prevent such a syndrome is quite limited. In the present study, we aimed to restore epidural fat using adipose tissue engineered from adipose derived stem cells (ASCs) in a rabbit dorsal laminectomy model. ⋯ As to the defect treated with PLGA alone or left untreated, either fine or dense scar tissue adhering to the dura mater was observed. Moreover, we could track the implanted ASCs labeled by magnetic nanoparticles within epidural area for as long as four weeks by MRI detection. Thus, adipose tissue engineered from ASCs exhibited great potential in restoration of epidural fat to prevent formation of epidural fibrosis.