Figure 1.

Histopathology of the skin at 14 days after the lesion. There was mostly a necrotic epidermis, with maturing granulation tissue, with numerous immune cells infiltrating the dermis for control animals (A), with more abundant epithelial necrosis, and liquefaction of the dermis with follicular-like inflammatory infiltrate in SDA group (B), with higher density collagen for simple gel group (C), well-preserved epidermis and scant granulation tissue vessels for G+NPS group (D), thick epidermis and densely packed bundles of collagen fibers for the G+EXO group (E), and a continuous epidermis with well-organized collagen fiber bundles in the dermis for G+NPS+EXO group (F). HE staining: (A–F) ×100. EXO: Exosomes; G: Gel; HE: Hematoxylin–Eosin; NPS: Silver nanoparticles; SDA: Silver sulfadiazine