Fig. 7: Slow released Reelin with mesoporous silica nanoparticles promoted tendon regeneration.

A TEM and SEM images displaying the spherical morphology, highly porous structure, a uniform size of ~190 nm and the cone shaped pores with large opening in MSNs. B Reelin release with and without MSNs over the course of 7 days. C The cytoskeletons in control, MSNs and MSNs-Reelin groups marked by phalloidin. D The live and dead cells in control, MSNs and MSNs-Reelin groups, demonstrated by Calcein-AM and PI staining. E The proliferation of TSPCs in control, MSNs and MSNs-Reelin groups, as assessed by Ki67 staining. F The HE staining, Masson trichome staining and collagen content analysis of Achille tendon in control, defect, MSNs, Reelin and MSNs-Reelin groups 4 weeks postoperatively. G The collagen fibers arrangement and diameter distribution visualized from cross-sections (upper panel) and longitudinal sections (lower panel) of Achilles tendons in control, defect, MSNs, Reelin and MSNs-Reelin groups, analyzed by TEM and SEM. H Sagittal T2-weighted MRI scans of Achilles tendon and the semi-quantitative data in control, defect, MSNs, Reelin and MSNs-Reelin groups. Red arrow: indicate the inflammation signal. Data were presented as Mean ± SD. n = 3 biological replicates per group in (B). Each dot represents one individual replicate (n = 3 biological replicates per group in (D, E); n = 5 biological replicates in (F, H)). Statistical significance was analyzed by One-way ANOVA with Tukey’s multiple comparisons test (D, E, F, H).