Fig. 14.

Modifications of EVs membrane. Left: E7-Exos delivered KGN to SFSCs to enhance cartilage regeneration. Right: PPD-sEVs reversed the surface charge and enhanced OA treatment. (A) Diagram of exosome engineering to enhance the delivery of KGN to SFSCs, and for cartilage regeneration. (B) Fluorescence images show that KGN was selectively delivered to SFSCs instead of chondrocytes (n = 3), scale bar = 10 μm. (C) Typical microscopic images of cartilage tissues in different treatment groups by HE staining and SO-FG staining. Reproduced with permission [30]. Copyright 2021, Elsevier. (D) Schematic diagram of sEVs reverse surface charge modification strategy by PPD. (E) DiO (green) labeled sEVs or PPD-sEVs chondrocyte uptake, scale bar = 50 μm. (F) Positive chondrocyte rate for uptake of DiO labeled sEVs or PPD-sEVs. (G) Cartilage degradation assessed by H&E and SO-FG staining, scale bar = 200 μm; Reproduced under the terms of the CC-BY 4.0 [32]. Copyright 2021, The Authors, published by Wiley-VCH.