fig4

Figure 4. Effect of down-regulation of NRP1 level in MSC-Exo on vascular endothelial repair. (A) Western blot screening identified siRNA1 as the most effective knockdown sequence among three candidate siRNA construct (siRNA1-siRNA3); (B) FCM showed that downregulation of NRP1 in MSC-Exo attenuated its anti-apoptotic effect; (C) Wound healing assay shows that NRP1 knockdown in MSC-Exo reduces its ability to promote migration of injured PMVECs; (D) Transwell migration assay confirmed that NRP1 knockdown in MSC-Exo diminished its pro-migratory effect. Scale bar = 50 μm. All experiments were independently repeated three times. Data are presented as mean ± SD. Statistical analysis was performed using one-way ANOVA followed by Tukey’s multiple comparisons test. ^*P < 0.05; ^**P < 0.01; ^***P < 0.001. NRP1: Neuropilin-1; MSCs: mesenchymal stem cells; MSC-Exo: mesenchymal stem cell-derived exosomes; siRNA: small interfering RNA; Si-Exo: exosomes derived from NRP1-silenced mesenchymal stem cells; Con-Exo: exosomes derived from control mesenchymal stem cells; LPS: lipopolysaccharide; PMVECs: pulmonary microvascular endothelial cells; FCM: flow cytometry; NC: normal control; SD: standard deviation; ANOVA: analysis of variance.