Fig. 7

Evaluation of EVs release in FEC hydrogel and cellular uptake in NP cells. A Schematics showing NP cells culture with EVs, EVs@FEC hydrogel and FEC hydrogel. The pore size of transwell is 0.4 μm, allowing EVs to get through. B Equivalent PKH-26-labelled EVs in PBS or FEC hydrogel were cultured with NP cells for a week. Representative immunofluorescence images showed the uptake of EVs in NP cells, and the uptake rate was evaluated based on the mean fluorescence intensity (right panel). C Flow cytometry of NP cells indicated the uptake rate of PKH-26-labelled cells. D Representative confocal 3D images of PKH-26-labelled EVs in FEC hydrogel at 37℃ and the EVs retention rate was evaluated based on the mean fluorescence intensity (E). F Expression of ACAN, COL2A1, MMP3, and MMP13 measured by western blot in NP cells cultured with EVs, EVs@FEC or FEC at specific time points. Data were presented as mean ± SD of three independent replicates. P > 0.05 (ns, not significant), **P < 0.01, and ***P < 0.001