Fig. 3.

Exosomes derived from A549 cells induced morphological changes in microglia and increased microglial proliferation. A. Representative immunofluorescence images showed the morphological changes incubated with exosomes for 24 h. Microglia cytoskeletons are labeled with phalloidin (green), and nuclei are labeled with DAPI (blue). Quantitative results for the numbers of branches per cell were showed (n = 7). Scale bar, 50 µm. B. The proliferation of microglia cells incubated with tumor-derived exosomes (20 ng/mL) was detected by CCK-8 assay at 6, 12, and 24 h, and statistical analysis was performed (n = 4). C. Wound healing of HMC3 was used to examine microglial mobility incubated with exosomes. Images were taken 0, 6, 12, and 24 h after wound scratching. The migration area was quantified (n = 4). Scale bar, 400 µm. D, E. The effect of A549-derived exosomes on the activation of microglia was analyzed by western blot analysis (D) and qPCR. Histogram shows relative protein expressions of CD16, CD80, Arg1, and Mrc1 normalized to the PBS-treated group (n = 3) (*P < 0.05, **P < 0.01).