FIG 4.

Effect of R-plsExos or R-ECExos on normal recipient ECs. (a) The transendothelial electrical resistance (TEER) values of normal mouse recipient BMECs were measured after treatment with normal plsExos (mock) or R-plsExos at 400, 2,000, or 8,000 Exo particles per cell for 72 h. *, P < 0.05. (b) The TEER values of normal human recipient BMECs were measured after a 72-h treatment with normal ECExos (mock) or R-ECExos (2,000 Exo particles per cell), which were pretreated with 20 μg/ml of RNase in the presence or absence of 0.1% saponin. **, P < 0.01. (c) Immunofluorescence staining of tight junctional protein ZO-1 (red) in normal human recipient BMECs that were treated with different Exos for 72 h. The yellow arrowheads indicate the decreased signals of paracellular ZO-1. Nuclei of human recipient BMECs were counterstained with DAPI (blue). (d) Relative fluorescent intensities of paracellular ZO-1. Normal rabbit serum was used as negative reagent control during immunofluorescent staining (Fig. S4). Scale bars, 20 μm. Statistical significance was determined using one-way analysis of variance. *, P < 0.05.