Fig. 2

H-SCs-Exos promotes intraneural angiogenesis and nerve repair after sciatic nerve injury. (A). Representative TEM for N-/H-SCs-Exos (scale bar = 100 μm). (B). NTA for concentration and size of N-/H-SCs-Exos. (C). Western blot assay for detecting exosomal-specific markers TSG101, CD9, and CD63 and cytoplasm marker calnexin. (D–F). Representative tube formation, transwell invasion, and EdU assay for evaluating endothelial angiogenic capacity after N-/H-SCs-Exos treatment (scale bar = 200–50 μm). (G). Data analysis for D to F (n = 5 rats/group). (H). PKH-67-labeled N-H-SCs-Exos (green) track in intraneural endothelial cells (ECs; CD31+, red) of injured sciatic nerve sites (scale bar = 50 μm, n = 5 rats/group). (I). CD31 + PKH-67+/CD31 + ratio. (J). CD31 + ECs per field analysis. (K). Representative immunofluorescent staining of neurofilaments (NF-200, green), myeline (MBP, red), and nuclei (DAPI, blue) to evaluate post-injury nerve regeneration (scale bar = 50 μm, n = 5 rats/group) and data analysis shown in L to N. Representative footprints of rats with saline or N-/H-SCs-Exos administration at 8 weeks after sciatic nerve crush injury. The left image shows the control group and the right image the sham or operative group. (O). Sciatic functional index calculation to evaluate functional recovery from week 1 to 8 after sciatic nerve injury (n = 5 rats/group). ^*P < 0.05, ^**P < 0.01, ^***P < 0.001. Bars represent group means ± SD. A Student’s t test was used for comparisons. NF-200: Neurofilament-200; MBP: Myelin basic protein; TEM: Transmission electron microscope; NTA: Nanosight tracking analysis; SFI: Sciatic functional index