FIG. 4.

Bridges loaded with E14 EGFP⁺ spinal progenitors enhance axon elongation at 8 weeks after transplantation in T9-10 hemisection. (A) Qualitatively, NF-200⁺ axon expression is greater in bridges containing E14 EGFP⁺ spinal progenitors compared to adult EGFP⁺ spinal progenitors and empty bridges. (B) Quantification of regenerating axons was binned into three 0.75 mm transverse sections of the bridge: R-rostral, M-middle of the injury, and C-caudal. (C) Axon density is increased in E14 EGFP⁺ spinal progenitor-loaded bridges compared to adult EGFP⁺ spinal progenitor-loaded and empty bridges at 8 weeks postinjury. This increase is most dramatic in the rostral and caudal sections of the bridges. By 6 months, axon density is similar for all conditions. Data are represented as mean ± standard deviation. n = 6 mice per bridge condition, *p < 0.05, **p < 0.01, ***p < 0.001. Scale bar 200 μm.