Fig. 5
Size-based tEV subpopulations reduce the transendothelial electrical resistance (TEER) of hCMEC/D3 in a dose-dependent fashion. (A) In vitro internalization of fluorescently labeled tEV subpopulations (2 K, 10 and 100 K) with DiD and SYTO TM into hCMEC/D3. (B) Real time of TEER measurement of a monolayer of hCMEC/D3 treated with ~ 109 (particle/ml) of tEV and uEV size-based subpopulations in composition with untreated (served as a negative control), TNFα/IFNγ (10 ng/mL) treated (served as a positive control) cells. The percentage of TEER in a monolayer of untreated hCMEC/D3 (served as a negative control) and TNFα/IFNγ (10 ng/mL) (served as a positive control) were compared with different concentrations of different tEV and uEV subpopulations. (C) The fold changes in the percentages of TEER values in response to TNFα/IFNγ (10 ng/mL) and different tEV subpopulations (2 K, 10 and 100 K) as normalized to control and their uEV respectively. Data are normalized to time 0 and given as mean ± SEM of at least three independent biological experiments (n ≥ 3) and n = 12 for the control and TNFα/IFNγ groups and one-way analysis of variance with a multiple comparisons test (Dunnet test, p value < 0.05 considered significant) was used to evaluate the statistical significance between treatments versus negative control and Tukey’s test at the value of *p < 0.05 was applied to evaluate the statistical significance between different treatments; *, **, ***, ****: significantly different from controls (p < 0.05, p < 0.01, p < 0.001 and p < 0.0001 respectively)