Fig. 7
M2-EVs protected mice from DSS-induced colitis through their protein cargos. A Schematic diagram showing the experimental procedure. 2-month-old male C57BL/6J mice were intravenously injected with PBS or regular or heated M2-EVs in PBS (3 × 108/g) on day 1, 4, and 6. All mice were given 1.5% (w/v) DSS in drinking water from day 4–11 and sacrificed on day 11. N = 4–5/group. B Representative colon images of colitis mice that received PBS or regular or heated M2-EVs in PBS. C M2-EVs, but not heated M2-EVs, prevented the shortened colon length in mice induced by DSS treatment. D The levels of cytokines in the media of ex vivo cultured colonic tissues. Released cytokine was normalized to the protein concentration of tissue lysates. E Expression of pro-inflammatory cytokine genes in colon tissues. F Representative images of H&E-stained sections of colon tissues. In the bar graphs, each dot represents one mouse. Data presented as mean ± SEM. * P < 0.05 and ** P < 0.01 relative to the control colitis mice received PBS (bar with black dots)