Construction of PRP-containing nanofibrous scaffolds for controlled release and their application to cartilage regeneration

Platelet-rich plasma (PRP) has been widely used for decades in the clinic, since an abundance of growth factors can be released when it is activated. However, its clinical use is limited because the release of growth factors is temporal and PRP lacks mechanical strength. The aim of this study was to incorporate PRP-derived growth factors into PCL/gelatin nanofibers using the emulsion electrospinning method to determine how growth factors are released from the scaffolds and how the presence of these factors enhances the bioactivity of the scaffolds. Scaffolds with or without PRP were prepared and characterized. The release of proteins from scaffolds over time and rabbit BMSC chemotaxis, proliferation, and chondrogenic induction were quantified in vitro. The in vivo restoring effect of the scaffolds was also evaluated by transplanting the scaffolds into a cartilage defect in an animal model, and the outcomes were determined by histological assessment, micro-CT scanning, and IL-1 measurement. The results showed that the mechanical properties of the scaffolds were mildly compromised due to the addition of PRP, and that the sustained release of growth factors from PRP-containing scaffolds occurred up to similar to 30 days in culture. The scaffold bioactivity was enhanced, as BMSCs demonstrated increased proliferation and notable chemotaxis in the presence of PRP. Chondrogenesis of BMSCs was also promoted when the cells were cultured on the PRP scaffolds. Furthermore, the PRP scaffolds showed better restorative effects on cartilage defects, as well as anti-inflammatory effects in the joint cavity (the IL-1 level was decreased). In conclusion, the results of the current study indicate the potential for using a PRP-containing electrospun nanofibrous scaffold as a bioactive scaffold, which is beneficial for optimizing the clinical application of PRP.