Figure 5

Knocked down CLIC1 expression inhibits capillary-like network formation and branching morphogenesis. A. Microscopy of control or CLIC1 knockdown lines in a collagen network formation assay indicated decreased network formation and defective branching morphogenesis in cells with CLIC1 knockdown. In addition to having less dense network patterning (exemplified by blue arrowheads), cell aggregations were found where normal branchpoints should have been (exemplified by red arrows). Black arrowheads indicate regularly spaced network patterning, and black arrows indicate normal branchpoints. Scale bar, 50 μm. B. Quantification of surface area occupied by endothelial cells showed a significant decrease in surface area occupation by cells with CLIC1 knockdown. Mean surface area occupied by endothelial cells for each cell line is shown with standard deviation. (*p < 0.01). C. Quantification of branchpoint numbers revealed a significant decrease in the number of branchpoint formations in cells with CLIC1 knockdown. One branchpoint was considered any focal intersection of two or more cords. The mean number of branchpoints for each cell line is shown with standard deviation. (**p < 0.001).