Fig. 2.

WPBs were misshaped in ru mice. A and B: Representative immunofluorescence images of primary ECs are shown. ECs from WT (A) and ru (BLOC-2 HPS6 deficiency) (B) were isolated from 4-week-old male mice and cultured for 10 days. After immunofluorescence staining of VWF (green), WPBs were examined under a confocal microscope. Typical elongated WPBs in WT ECs were rarer in ru ECs. Scale bar: 5 μm. a and b: The corresponding magnified regions (white boxes) of A and B showed that WPBs were misshaped in ru ECs. Scale bar: 2 μm. C: Quantification analysis of the Feret's diameters of WPBs in WT and ru ECs. The VWF positive organelles (green in A and B) whose Feret's diameter is greater than 0.3 μm were counted as WPB. The images were analyzed with NIH Image J software. The distribution of WPBs was plotted as an empirical cumulative distribution as a function of their Feret's diameters. The distribution of WPBs in ru ECs shifted towards shorter Feret's diameters compared with that in WT ECs. The total number of WPBs analyzed: 4900 WPBs from WT ECs, 2551 WPBs from ru ECs, *** P < 0.001. D: A differential plot of the Feret's diameter of ru WPBs minus that of WT WPBs. There were more WPBs in ru ECs than in WT ECs in the positive range, while in the negative range there were less WPBs in ru ECs than in WT ECs. More WPBs were distributed in the range of shorter Feret's diameter in ru ECs than in WT ECs.