Fig.4.

HD nesting phenotype reversed by inhibition of canonical Notch pathway. A) Immunocytochemistry of the proliferation marker Ki67. The proliferation decreases in both HD (180 repeats) and control (21 repeats) lines over increasing time points of striatal differentiation. Pictures were taken at the magnification of 20X. B) Graph shows the expression of proliferation marker Ki67 at 0, 7, 14, 28, 42, and 56 days of iPSC-derived striatal cultures. The Ki67 expression decreases over increasing time points of differentiation in both HD and control lines. C) Inhibition of canonical Notch pathway showed significant reduction in nestin expressing NPC population in both control and HD cultures. Representative images of the 1 week inhibition of canonical Notch pathway using 10 μM DAPT during striatal differentiation. D) Notch inhibition decreases percentage of nestin+ cells in all lines, but a greater percentage in HD to the level of control. E) Two of the HD lines (HD 71 and HD 180) showed significant difference in TuJ1 population F) No significant difference was observed in GFAP+. G) Images of H) and quantification of apoptotic cell death by means of TUNEL assay reveal no significant increase in cell death due to Notch inhibition. Statistical analysis was performed using paired T-test for Fig. 4 B), D) – F) and one-way ANOVA for Fig. 4 H). (*p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001) Error bars represent SEM.