Fig. 2

Detection of mesenchymal stem cell (MSC)-derived neuron-like cells in gelatin sponge (GS) scaffold 14 days after culture. a, b Scanning electron microscopy (SEM) shows differentiating MSCs bearing long and branched processes (a) (red arrows) on the surface of GS. One of the processes appears to make contact with another cell body (b) (red arrowheads). c Transmission electron microscopy shows a few synapse-like structures between two processes of differentiating MSCs (red arrowheads). d PSD95 expression was detected by Western blotting (1 = the M group, 2 = the MN group, 3 = the MT group, 4 = the MN + MT group). PSD95 level is highest in the MN + MT group compared with the M, MN, and MT groups (One-way analysis of variance with least significant difference test statistics was performed; *P < 0.05, ^# P < 0.05, ^& P < 0.05). e–h Expression of PSD95 and SYP was detected by immunofluorescence staining in the M, MN, MT, and MN + MT groups. All groups exhibited PSD95-positive cells, whereas SYP-positive cells were absent in the M and MN groups (white arrows). Scale bars = 20 μm in (e–h). M, MSCs; MN, NT-3-MSCs; MT, TrkC-MSCs