FIGURE 5.

JAK2V617F-mutant cardiac endothelial cells (ECs) display a vasculopathy phenotype. A, Representative flow cytometry plots (left) and quantitative analysis (right) showing increased apoptosis in cultured JAK2V617F ECs (black bar) compared to wild-type ECs (gray bar). B, Wild-type and JAK2V617F-mutant cardiac ECs (8 × 10⁴) were seeded in Matrigel matrix in 48-well plate. Representative tube formation after a 4-hour incubation is shown. Magnification: 10×. C, Quantification of tube formation was performed on images taken at 4× magnification by counting the number of nodes (or branch points), tubes, and loops in four non-overlapping fields. Results are expressed as the mean ± standard error of the mean (n = 4). Data are from one of two independent experiments on two different pairs of cardiac ECs that gave similar results. D, Gene expression level of EGFL7 in wild-type (gray) and JAK2V617F (black) cardiac ECs measured using realtime quantitative polymerase chain reaction. Gene expression in VF ECs is shown as the fold change compared to the average wild-type EC expression which was set as “1.” (n = 3 in each group) *P < .05