Figure 1.

miR-31 Shuttled by SMSC-Derived EVs Stimulates Chondrocyte Proliferation In Vitro

(A) Representative immunofluorescence micrographs of CFSE (green)-labeled EVs internalized by chondrocytes, the nucleus of which was stained with 4′,6-diamidino-2-phenylindole (DAPI; blue) (×400, scale bar, 50 μm). (B) The expression of miR-31 determined by qRT-PCR in the supernatant and in SMSC-extracted EVs. ∗p < 0.05 compared with supernatant. (C) The expression of miR-31 determined by qRT-PCR in miR-31 inhibitor-treated chondrocytes with addition of SMSC-derived EVs. (D) Chondrocyte proliferation upon miR-31 inhibitor transfection and treatment with SMSC-derived EVs measured by the CCK-8 assay. (E) The number of migrated miR-31 inhibitor-transfected chondrocytes treated with SMSC-derived EVs measured by the Transwell assay. (F) Representative images of migrating chondrocytes (×200). ∗p < 0.05 compared with inhibitor-NC-transfected chondrocytes; #p < 0.05 compared with miR-31 inhibitor-transfected chondrocytes treated with PBS. Data are shown as mean ± standard deviation of three technical replicates. Unpaired t test was applied for comparison between two groups. Data comparison among multiple groups was performed using one-way ANOVA with Tukey’s post hoc test. Data comparison between groups at different time points was performed using repeated-measures ANOVA with Bonferroni correction.