Extracellular Vesicles from Vascular Endothelial Cells Promote Survival, Proliferation and Motility of Oligodendrocyte Precursor Cells
Fig 5
EC-derived EVs promoted OPC survival, proliferation and migration.
EVs were isolated from conditioned media of various types of endothelial cells (ECs) or Rat-1 fibroblastic cells, suspended in fresh serum-free medium and added to OPC cultures (50 μg/ml of proteins), which were maintained for 2 days. As control, OPCs were cultured in fresh serum-free medium without EVs. (A) Phase contrast images. Scale bar, 50 μm. (B) OPCs were stained with Hoechst 33342, and the nuclear morphology was observed. The proportion of pyknotic nuclei (red arrowheads) in OPCs with EC-derived EVs was smaller when compared to Rat-1-EVs. Scale bar, 50 μm. (C) After labeling with BrdU for the last 4 h of culture, cells were fixed and stained with an anti-BrdU antibody. Cell nuclei were stained with propidium iodide (PI, red). Many BrdU-positive cells (green) were observed in HUVEC-EV. Scale bar, 50 μm. (D) Phase contrast images of OPC migration 16 h after plating (Insets: OPC aggregates 1 h after plating). Scale bar, 200 μm. (E) The proportion of pyknotic nuclei in the presence of EC-derived EVs (except for bEnd.3-EVs) was significantly smaller when compared to those in the presence of Rat-1-EVs. Results are shown as mean ± SE (N = 8 in each condition). ***p<0.001 against control. ###p<0.001 against Rat-1-EVs. (F) The proportion of BrdU-positive cells in the presence of EC-derived EVs (except for HMVEC-EVs) was significantly larger when compared to Rat-1-EVs. Results are shown as mean ± SE (N = 8 in each condition). ***p<0.001 against control and Rat-1-EVs. (G) EVs derived from ECs significantly promoted OPC migration, when compared to control and Rat-1-EVs. Results are shown as mean ± SE (N = 4 in each condition). ***p<0.001 against control and Rat-1-EVs.