FIGURE 3.

SC‐EXO could be uptake by SSCs and up‐regulate Stra8 and Sycp3 expression. A, Flow cytometric analysis of the uptake of SC‐derived exosomes (SC‐EXO) labelled with PKH26 at various times points. SSCs were treated with SC‐EXO labelled with PKH26 (8.88 × 10⁹) for 6, 12, 24, 36 and 48 h. SC‐derived exosomes (SC‐EXO) labelled with PKH26 were completely uptaken by SSCs after 24 h. SSCs labelled with PKH26 were used as positive control. B, Representative fluorescent confocal images of SSCs that were exposed to PKH26‐labelled exosomes (red) from Sertoli cells for 24 h. Nuclei were stained with DAPI (blue). Scale bars, 20 μm. C‐D, RT‐qPCR analysis of Stra8 and Sycp3 expression in SSCs treated with SC‐EXO at different concentrations for 24 h. SSCs without exosome treatment were used as control. EXO‐1:4.44 × 10⁹ particles/mL, EXO‐2:8.88 × 10⁹, EXO‐3:1.33 × 10¹⁰ particles/mL. The copy number of mRNA of each gene was normalized with Gapdh, and the data were obtained from three independent experiments and are presented as mean ± SD; *P < 0.05