Fig. 4
From: Recycling of endocytic BDNF through extracellular vesicles in astrocytes
Vamp3-dependent secretion of QD-BDNF from CD63-positive vesicles. (A) Representative QD-BDNF kymographs generated from CD63-EGFP-transfected astrocytes. Arrow heads: disappearance of CD63-EGFP-positive QD-BDNF fluorescence. (B) Average fractions of secreted QD-BDNF particles with (+) or without CD63 (-) among total secreted QD-BDNF particles. N = 24 cells (232 secreted QD particles). (C) Average percentages of ATP-induced QD-BDNF secretion events from vesicles with (+) or without CD63 (-). **P < 0.01, ****P < 0.0001. N = 10–11 cells (siSCR: 11 cells, 508 QD particles; siVamp3: 10 cells, 308 QD particles). siSCR: 3 independent experiments with 3–4 cells (107–224 QD particles per experiment); siVamp3: 3 independent experiments with 3–4 cells (91–114 QD particles per experiment). (D) Representative fluorescence images showing the colocalization of QD-BDNF with CD63-EGFP in astrocytes treated with siSCR or siVamp3. Yellow arrowheads indicate QD-BDNF colocalized with CD63-EGFP. Scale bar = 5 μm. (E) Average colocalization ratios (number of colocalized QD-BDNF particles among total QD-BDNF particles). *P < 0.05. N = 12 cells (1,737–1,962 QD particles). (F) Representative fluorescence images showing the colocalization of QD-BDNF with endogenous CD63 in astrocytes treated with siSCR or siVamp3. Yellow arrowheads indicate QD-BDNF colocalized with anti-CD63 signals. Scale bar = 5 μm. (G) Average colocalization ratios (number of colocalized QD-BDNF particles among total QD-BDNF particles). *P < 0.05. N = 20–29 cells (2,150-2,464 QD particles).
