Development of ovalbumin implants with different spatial configurations for treatment of peripheral nerve injury

Peripheral nerve injury (PNI) seriously affects the health and life of patients, and is an urgent clinical problem that needs to be resolved. Nerve implants prepared from various biomaterials have played a positive role in PNI, but the effect should be further improved and thus new biomaterials is urgently needed. Ovalbumin (OVA) contains a variety of bioactive components, low immunogenicity, tolerance, antimicrobial activity, non-toxicity and biodegradability, and has the ability to promote wound healing, cell growth and antimicrobial properties. However, there are few studies on the application of OVA in neural tissue engineering. In this study, OVA implants with different spatial structures (membrane, fiber, and lyophilized scaffolds) were constructed by casting, electrospinning, and freeze-drying methods, respectively. The results showed that the OVA implants had excellent physicochemical properties and were biocompatible without significant toxicity, and can promote vascularization, show good histocompatibility, without excessive inflammatory response and immunogenicity. The in vitro results showed that OVA implants could promote the proliferation and migration of Schwann cells, while the in vivo results confirmed that OVA implants (the E5/70% and 20 kV 20 μL/min groups) could effectively regulate the growth of blood vessels, reduce the inflammatory response and promote the repair of subcutaneous nerve injury. Further on, the high-throughput sequencing results showed that the OVA implants up-regulated differential expression of genes related to biological processes such as tumor necrosis factor-α (TNF-α), phosphatidylinositide 3-kinases/protein kinase B (PI3K-Akt) signaling pathway, axon guidance, cellular adhesion junctions, and nerve regeneration in Schwann cells. The present study is expected to provide new design concepts and theoretical accumulation for the development of a new generation of nerve regeneration implantable biomaterials.