Stabilization of porous chitosan improves the performance of its association with platelet-rich plasma as a composite scaffold

Abstract

This study offers innovative perspectives for optimizing of scaffolds based on correlation structure-function aimed the regenerative medicine. Thus, we evaluated in vitro performance of stabilized porous chitosan (SPCHTs) associated with activated platelet-rich plasma (aP-PRP) as a composite scaffold for the proliferation and osteogenic differentiation of human adipose-derived mesenchymal stem cells (h-AdMSCs). The porous structure of chitosan (PCHT) was prepared similarly to solid sponges by controlled freezing (-20 °C) and lyophilization of a 3% (w/v) chitosan solution. Stabilization was performed by treating the PCHT with sodium hydroxide (TNaOH), an ethanol series (TEtOH) or by crosslinking with tripolyphosphate (CTPP). The aP-PRP was obtained from the controlled centrifugation of whole blood and activated with autologous serum and calcium. Imaging of the structures showed fibrin networks inside and on the surface of SPCHTs as a consequence of electrostatic interactions. SPCHTs were non-cytotoxic, and the porosity, pore size and Young's modulus were approximately 96%, 145 μm and 1.5 MPa for TNaOH and TEtOH and 94%, 110 μm and 1.8 MPa for CTPP, respectively. Stabilization maintained the integrity of the SPCHTs for at least 10 days of cultivation. SPCHTs showed controlled release of the growth factors TGF-β1 and PDGF-AB. Although generating different patterns, all of the stabilization treatments improved the proliferation of seeded h-AdMSCs on the composite scaffold compared to aP-PRP alone, and differentiation of the composite scaffold treated with TEtOH was significantly higher than for non-stabilized PCHT. We conclude that the composite scaffolds improved the in vitro performance of PRP and have potential in regenerative medicine.

Keywords: Chitosan; Growth factors; Platelet-rich plasma; Regenerative medicine; Scaffolds.