Fig. 8

Histological evaluation of nerve grafts at the 12th week after transplantation. a In the immunofluorescence photographs (the first column, longitudinal sections of the nerve grafts; the second column, transversal sections of the nerve grafts middle segment), the axons exhibited red fluorescence, the myelin sheath exhibited green fluorescence, and all nuclei showed blue fluorescence. The photographs in the third and fourth columns show Toluidine Blue staining and transmission electron microscopy (TEM) images, respectively, of nerve grafts distal segment. Scale bars: 1000 μm (leftmost column), 50 μm (second column), 10 μm (third column) and 5 μm (rightmost column). b The mean density of myelinated nerve fibers in Microtissue group was significantly higher than the 2D group (p < 0.05). c, d The mean diameter of myelinated nerve fibers and mean thickness of myelin sheaths in the Microtissue group were significantly higher (p < 0.05) than those in the 2D group, and there was no statistical difference between Microtissue group and ANG group