Figure 2.

The ZO-1 immunocytochemistry is consistent with tight junction formation after treating HUVECs with astroglial conditioned media. The HUVEC monolayers were treated with unconditioned media (A) or C6 astroglial conditioned media with (B) vehicle, (C) C6 astroglial media with TNF-α (0.1 µg/mL), or (D) C6 astroglial media with MMP-9 (2.5 µg) and probed for ZO-1 by immunocytochemistry (red, ZO-1; blue, DAPI nuclear probe; scale bar = 20 µm). DAPI indicates 4′,6-diamidino-2-phenylindole; HUVECs, human umbilical vein endothelial cells; MMP-9, matrix metalloproteinase 9; TNF-α, tumor necrosis factor-α; ZO-1, zona occludens 1.