Modulating axonal growth and neural stem cell migration with the use of uniaxially aligned nanofiber yarns welded with NGF-loaded microparticles

In tissue repair, cell behaviors can be modulated by sensing and responding to the topographical and biochemical cues provided by the surrounding microenvironment. Herein, we designed and fabricated a class of uniaxially aligned nanofiber yarns welded with electrosprayed microparticles to guide the directional growth of axons and the migration of neural stem cells. By tuning the depositing density of microparticles on the nanofiber yarns, the surface roughness was varied, which facilitated the directional axon outgrowth of PC12 and SH-SY5Y cells and the alignment of Schwann cells. The microparticles were further modified by loading nerve growth factors in the core and then deposited on the nanofiber yarns. Owing to the synthetic effects provided by the physical and biological signals, the migration of neural stem cells was significantly accelerated. Taken together, the uniaxially aligned nanofiber yarns welded by functionalized microparticles show promising use in manipulating axonal growth and the migration of neural stem cells, which will provide a novel approach to clinical repair of nerve injuries.