“Cell climbing stones” – varying the surfaces of electrospun nanofibers with protrusions as secondary structures to manipulate neural cell behaviors

Effective neural repair requires the precise regulation of neurite outgrowth and coordinated migration of neural stem cells (NSCs) and Schwann cells (SCs). The synergistic integration of topographical cues, chemical signals and electrical stimulation can significantly enhance this process, among which topographical modulation has emerged as a research focus due to its direct regulatory effects on cellular behavior. Micro/nanoscale topological features (nanogrooves and protrusions) can markedly promote neurite outgrowth and cell migration by matching the mechanical characteristics of growth cone filopodia (100-300 nm). Building upon our previous work, we designed a series of aligned nanofibers with SiO₂ protrusions of varying sizes and concentrations to mimic "cell climbing stones," systematically investigating their regulatory effects on neurite growth, and the migration of NSCs and SCs. The results demonstrated that nanofibers with oriented protrusions as secondary structures significantly enhanced the motility of SCs and NSCs while promoting neurite extension. Notably, nanofibers fabricated with 200 nm SiO₂ nanoparticles blended with PCL at 6% SiO₂ concentration exhibited the most pronounced regulatory effects on neural cell behavior.