Wharton's jelly-derived nanovesicles for targeting intervertebral disc degeneration

The present study was designed to characterize the matrix-bound nanovesicles (MBVs) in decellularized Wharton's jelly matrix (DWJ). We have previously used DWJ as a biomaterial demonstrating its efficacy in restoring the functional properties of human intervertebral disc (IVD) cells lost following degeneration (IDD), for which there is currently no cure. MBVs were isolated by ultracentrifugation from DWJ, characterized by transmission electron microscopy, nanoparticle tracking assay, and surface marker expression. MBVs uptake into cells was assessed by CalceinAM labeling. Nitric oxide production was evaluated by Griess assay. The response of IVD cells was assessed by cell motility (wound scratch assay) and protein expression (immunocytochemistry). MBVs were subjected to human growth factors array to evaluate different growth factors and global miRNA profiling (obtained from miRNA libraries, sequencing-NextSeq system and the GeneGlobe Data Analysis). MBVs were readily internalized by cells without affecting the viability. MBVs suppressed the acquisition of the M1 phenotype in LPS-stimulated macrophages, positively influence the cell migration of IVD cells and the expression of molecular markers associated with the restoration of the chondrocyte-like phenotype. A preliminary analysis of growth factor content and miRNA expression profiling suggest that MBVs carry a cargo functionally relevant for the IVD cell metabolism. The discovery of MBVs in DWJ leads to considering them as an integral component of DWJ-based scaffolds designed to repair or regenerate a damaged tissue. The pro-discogenic properties of MBVs demonstrate that there are grounds for expanding the study of DWJ-derived MBVs for potential therapeutic applications in the treatment of IDD.