Reactivation of Denervated Schwann Cells by Embryonic Spinal Cord Neurons to Promote Axon Regeneration and Remyelination

Figure 5

SC quantity and phenotype change in distal nerve stump after the 1^st and 2^nd surgery-I. Longitudinal sections of the distal part of the transplanted site were stained with S100 (an SC cytoplasmic marker) and P75 (a dedifferentiated SC marker). (a–d) In the vehicle group, one month after the 1^st surgery, the intensity of P75 was significantly higher and the intensity of S100 was lower on the transected side than on the intact side. In the cell group, the increase in P75 expression and the decrease in S100 expression were not obvious compared with the vehicle group. (e–l) At 3 and 6 months after the 1^st surgery, the expression of both markers had gradually decreased to a low level in the vehicle group. In the cell group, P75 was maintained at a low level while S100 expression was maintained at a high level, and their levels did not significantly fluctuate. (m–p) Two weeks after the 2^nd surgery-I, the expression of P75 in the cell group increased, while the expression of S100 decreased; the vehicle group did not exhibit these changes. (u) The expression intensity of P75 and S100 in the vehicle group declined over time. In the cell group, a reversal in the expression of P75 (low to high) and S100 (high to low) was observed after excision of the transplanted cells. Scale bar = 100 μm.