Figure 3.

Immunofluorescence for claudin-1 (green) ((a), control and 3e, MPO-AAV) and ZO-1 (red) ((b) control and (e) MPO-AAV). Merged image ((c) control and (f) MPO-AAV) demonstrates that claudin-1 is expressed predominantly at cell to cell contact sites of adjacent PECs. Signals are distinctively concentrated in a dotted pattern in control sample (c). ZO-1, which is the major component of intracellular tight junction complexes, is visualized employing anti-ZO-1 antibody. Glomerular tufts also show positivity in ZO-1 staining. Colocalization of claudin-1 and ZO-1 is detected by confocal laser scanning microscopy (magnified view in (c) and (f)). In cellular crescents (f), lines that are double positive for anti-claudin-1 and anti-ZO-1 are observed (arrowhead); however, positivity of claudin-1 is less intense compared to ZO-1. Cell nuclei were stained with DAPI. (g) Occludin (red) is also expressed in crescentic lesion (arrowhead).