Fig. 8

miR-99b-5p derived from EMF-USPIO-sEVs regulated MFG-E8 expression. (A) Venn diagram displaying the potential target genes of miR-99b-5p, as predicted by miRWalk, RNA22, and miRDB databases. (B) Comparison of the top ten differentially expressed miRNAs (miR-374c-5p, miR-503-5p, miR-28a-5p, miR-146a-5p, miR-744-5p, miR-99b-5p, miR-205-5p, miR-324-5p, miR-221-3p, and miR-542-3p) between NC-sEVs and EMF-USPIO-sEVs using qRT-PCR. (C) miR-99b-5p binding sequence in the 3′-UTR of MFG-E8. D, H: Protein expression of MFG-E8 after cell transfection with miR-99b-5p mimics, miR-99b-5p inhibitor, and their respective NCs and semi-quantification. E-F: Transfection efficiency confirmation of miR-99b-5p in chondrocytes (E) and RAW246.7 (F). (G) Luciferase readings were obtained from either wt or mut MFG-E8 3′-UTR when co-transfected with control mimics or miR-99b-5p mimics. Transfection with miR-99b-5p mimics led to a reduction in luciferase activity relative to the control mimics, substantiating that MFG-E8 is a direct target of miR-99b-5p