3D-bioprinted RGD-Alg/GelMA/PCL scaffolds laden with Schwann-like cells for peripheral nerve reconstruction

Autograft nerve transplantation is widely considered the gold standard for treating peripheral nerve defects, but it does have certain drawbacks. Alternatively, tissue engineering holds significant promise for nerve regeneration. In this study, three-dimensional (3D) bioprinting was utilized to fabricate a nerve regenerative conduit with arginine-glycine-aspartic acid-modified sodium alginate (RGD-Alg)/gelatin methacrylate (GelMA)/polycaprolactone (PCL) laden with induced Schwann-like stem cells from human-exfoliated deciduous teeth (scSHEDs). Stem cells from human-exfoliated deciduous teeth (SHEDs) could be stably induced into scSHEDs, as indicated by enhanced immunofluorescence staining for S-100β, GFAP, and P0 proteins. The physical properties of the 6% RGD-Alg/5% GelMA hydrogel were determined through rheological and maximum tensile testing, displaying decent mechanical and rheological characteristics. Incorporating PCL layers into the hydrogel significantly enhanced the scaffold’s physical properties. Live/dead cell staining and nerve growth factor (NGF) release test confirmed the growth of scSHEDs within the 6% RGD-Alg/5% GelMA hydrogel. S-100β immunofluorescence and cytoskeleton stainings verified the growth of scSHEDs within the scaffold. Eight weeks after anastomosis in rat models with sciatic nerve defects, electrophysiological examination, functional assessment, and immunohistochemical staining were conducted. The results indicated that the 3D-bioprinted scSHED-laden RGD-Alg/GelMA/PCL scaffold enhanced the efficacy of promoting nerve regeneration compared to the hydrogel and hydrogel/PCL scaffolds. Overall, this study highlighted the potential of scSHEDs and PCL enhancement as viable improvements to RGD-Alg/GelMA hydrogels for constructing nerve regenerative conduit. The 3D-bioprinted composite scaffold is expected to provide new insights into peripheral nerve regeneration and has a wide range of clinical prospects.