Fig. 3

Damage to the spinal cord promoted the accumulation of Nestin-positive NSCs and increased the expression of BMP2 around the injured core. A The concentration of BMP2/4/7 within As-CM and LPS-As-CM was detected by ELISA. It shows that the expression of BMP2 and BMP4 in NSC-CM was upregulated by the addition of LPS-As-CM, compared with the As-CM-treated NSC-EVs (n = 5, data are the mean ± S.D; ∗p < 0.05, ns p > 0.05). B Western blot analysis showed that the expression of BMP2 in CM derived from astrocytes was increased by LPS stimulation (n = 3, data are the mean ± S.D; ∗p < 0.05, full-length original gels are included in Additional file 2: Figure S2). C Immunofluorescence staining of the section around the injured core at Day 3 post-SCI showed that Nestin-positive NSCs accumulated around the cavity. Compared to the sham group, the SCI rats had significantly higher expression of BMP2 in the areas around the cavity. Double staining of Nestin and BMP2 cells was observed in these areas (arrows indicate Nestin and BMP2 double-labeled cells in the areas around the cavity)