Figure 4. Integrins participated in the endocytosis of 293T-Exo by R28 cells. (A) Endocytosis was inhibited by pretreatment of RGD, but not by heparin. The nuclei were stained with DAPI (blue), the cytoskeleton was stained with tubulin (red), and 293T-Exo was stained with fluorescent-tag (green). Scale bar = 20 μm. (B) Efficacy of endocytosis of 293T-Exo by R28 cells was reversed due to increasing doses of RGD. (C) Efficacy of endocytosis of 293T-Exo by R28 cells was not affected by different doses of heparin. Data are presented as mean ± SD. *P < 0.05.