Fig. 5

Effects of MSC-MNPs on the polarization and phenotype of reactive astrocytes. (A) Schematic diagram of the coculture of MSC-MNPs and astrocytes. (B, C) Astrocyte reactivity was studied in cultured cells via a wound scratch assay. At 24 h after scratching, GFAP immunostaining revealed protrusions of polarized astrocytes, and there was no significant difference in protrusion length between the MSC-MNPs group and the MSC group. (D) Protrusion orientation was evaluated by the angles between the protrusion axes and the scratch line (indicated in B), which revealed that the number of astrocytes with protrusions preferentially oriented perpendicular to the lesion (45°−90°) was comparable between the MSC-MNPs group and MSC group. (E) RT-qPCR quantification of C3, Serping1, Clcf1, B3gnt5, Tm4sf1 and Ptx3 transcripts in cultured spinal cord astrocytes. The mRNA levels are normalized to that of GAPDH. (F-I) The levels of neurotrophic factors, including GDNF, NGF, CNTF, and BDNF, in the supernatant of astrocytes were detected using an ELISA experiment. *P < 0.05, **P < 0.01; n = 100 in C and D, n = 4 in E, n = 3 in F-I; Student’s t-test in C and E; Chi-square test in D.