Related to Fig. 4 . (A) TSPAN4-BFP stably expressing MEF cell line was seeded in fibronectin-coated dishes. Then cells were treated with 2.5 mM LLOMe along with or without 0.5 μM Latrunculin A for 22 h. Then stained with Cy5 and captured with live-cell mode. The marked regions in the large graphs were enlarged and demonstrated on their right. Scale bars denoted 20 μm for the large-view graphs, 5 μm for the small-view graphs. (B) Statistic result of the area of the extracellular lysosomal structure indicated by Cy5 in A. Error bars denoted ± SEM from three independent live-cell imaging experiments, >50 cells were analyzed per experiment and 155 cells were analyzed in total for each group. T test, ****P < 0.0001.