Biomimetic neural scaffolds: a crucial step towards optimal peripheral nerve regeneration

Abstract

Peripheral nerve injury is a common disease that affects more than 20 million people in the United States alone and remains a major burden to society. The current gold standard treatment for critical-sized nerve defects is autologous nerve graft transplantation; however, this method is limited in many ways and does not always lead to satisfactory outcomes. The limitations of autografts have prompted investigations into artificial neural scaffolds as replacements, and some neural scaffold devices have progressed to widespread clinical use; scaffold technology overall has yet to be shown to be consistently on a par with or superior to autografts. Recent advances in biomimetic scaffold technologies have opened up many new and exciting opportunities, and novel improvements in material, fabrication technique, scaffold architecture, and lumen surface modifications that better reflect biological anatomy and physiology have independently been shown to benefit overall nerve regeneration. Furthermore, biomimetic features of neural scaffolds have also been shown to work synergistically with other nerve regeneration therapy strategies such as growth factor supplementation, stem cell transplantation, and cell surface glycoengineering. This review summarizes the current state of neural scaffolds, highlights major advances in biomimetic technologies, and discusses future opportunities in the field of peripheral nerve regeneration.

Growth factors-based therapeutic strategies and their underlying signaling mechanisms for peripheral nerve regeneration

“…Many of these nerve scaffolds/conduits possess proper biocompatibility and mechanical strength that protect injured neurons and Schwann cells (SCs) from apoptosis and prevent the formation of scars [ 7 ]. However, some unknowns exist, such as the suboptimal effectiveness, that limit the availability of these scaffolds/conduits for clinical use [ 8 ]. To optimize their properties, increasing research efforts have focused on biomimetic neural scaffold/conduit fusing growth factors (GFs) to repair PNI and achieve superior therapy for promoting nerve regeneration and functional reinnervation [ 9 – 11 ].…”

Customized Scaffold Design Based on Natural Peripheral Nerve Fascicle Characteristics for Biofabrication in Tissue Regeneration

“…In the future, nerve graft design should reflect this microstructure information, design matching nerve fascicle microstructure characteristics of biomimetic repair nerve grafts, and achieve nerve gross morphology matching, nerve branch matching, and three-dimensional spatial pattern matching of nerve fascicles morphology. Tissue engineering customized nerve grafts can be a new solution to repair nerve defects in the future [35][36][37]. e limitations of this study are mainly due to the existing experimental conditions and the small human nerve Figure 6: e establishment of the database of peripheral nerve microstructure and its application to design a biofabrication nerve graft model according to the morphological characteristics of the nerve bundle.…”

From in vitro evaluation to human postmortem pre-validation of a radiopaque and resorbable internal biliary stent for liver transplantation applications

“…To match both of these criteria, copolymers of aliphatic polyesters and polyether are thought to be suitable candidates as they offer a large range of mechanical properties and degradation times, while they have also been approved by regulatory agencies for various applications. Many studies have, therefore, focused on poly(lactide)/poly(ethylene glycol) copolymers (PLA/PEG) in tissue engineering applications, ranging from vascular grafts to nerve guides and bone scaffolds [32][33][34][35][36]. In particular, we developed PLA-b-Poloxamer-b-PLA and PLA-b-Poloxamine-b-PLA triblock copolymers for ligament tissue engineering [37,38], and we have studied the non-linear viscoelastic behavior of PLA-b-PEG-b-PLA during their degradation to evaluate their potential for soft-tissue reconstruction [39,40].…”