TNF-α Enhances the Therapeutic Effects of MenSC-Derived Small Extracellular Vesicles on Inflammatory Bowel Disease through Macrophage Polarization by miR-24-3p

Figure 4

MenSCs-sEV^TNF-α relieves chronic recurrent colitis caused by DSS. Male C57 BL/6 mice () aged 6-8 weeks were given normal water for 7 days after 3% DSS solution for 1 week. The treatment was repeated once and small EVs were intraperitoneally injected into the DSS+MenSCs-sEV^TNF-α group on day 7 and day 16 (200 g/mouse). (a) The clinical symptoms of the mice were recorded daily as DAI scores, which were based on the varying degrees of weight loss, stool consistency, and hematochezia. (b) The length of the colon of each mouse was measured after euthanasia. (c) The levels of TNF-α, IFN-γ, IL-10, IL-1β, and IL-6 in colon tissue were measured by ELISA. (d) Neutrophil infiltration in the colon was detected by MPO activity. (e) Colon tissues were stained with hematoxylin and eosin to observe the inflammatory infiltration and structural integrity. Original magnification: ×100 (up) and ×200 (down).