Fig. 4: Histomorphology evaluation and nervous-specific protein expression of regenerated nerve fibers.

a Development process of regenerated nerve: I) charged neurotrophic factors transported through the defected nerve and formed aligned accumulation along the MF-NGC; which induced II) the formation of aligned cell-free fibrin cables and further caused migration and aggregation of Schwann cells onto the cables; III) the rapidly established Schwann cells cables facilitated the myelination of regenerated neurons. b Hematoxylin-eosin (HE) staining (blue: Schwann cell nuclei, red: cytoplasm), toluidine blue (TB) staining, and TEM images of cross-section of regenerated nerves. c Triple immunofluorescent staining images of nervous tissue-specific myelin basic protein (MBP) (green), S100 (red), and nervous axon basic protein (NF200) (green) and Tuj 1 (red), nuclei (blue) in regenerated nerve fibers, bars: 50 μm. d Relative expression level of MBP and S100. e Relative expression level of NF200 and Tuj 1. f Immunofluorescent staining images of calcium signaling pathway C-fos (red) and BDNF (green), nuclei (blue) in regenerated nerve fibers, bars: 20 μm. Relative expression of C-fos and BDNF were shown in g, h. i Schematic illustration of intracellular pathway for retaining continuous activation of regeneration-associated signaling pathway under Bio-iES. Data are expressed as mean values ±S.D. (n = 5, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001).