Fig. 2

SEMA4D is increasingly upregulated in neurons during human HD disease progression; changes in astrocyte GS expression and morphology are indicative of astrogliosis. Human brain autopsy sections from non-diseased “normal” human and HD pathological stage 0, 1, and 2 were processed for SEMA4D, Huc/HuD (neuronal cell body), GFAP (astrocytes), and GS (astrocyte cell body and processes). Brain regions included frontal cortex, parietal lobe, and striatum (caudate/putamen). a Representative images of frontal lobe illustrate upregulation of neuronally expressed SEMA4D (100-micron scale shown). Quantification of b SEMA4D expression in HucHUD+ cells and c HucHUD+ neuron density. d GFAP staining of frontal lobe are shown; soma is circled in binary image conversion. Fractal dimension analysis of GFAP+ astrocytes demonstrate significant changes between non-diseased and HD. Group differences and statistical significance was determined by an independent-samples t-test. e GS expression is reduced and retracted astrocytic endfeet are observed in HD, compared to normal. (20-micron scale shown). f Quantification of GS in GFAP+ cells. Each bar represents autopsy tissue from one individual; mean of the sum of integrated fluorescence intensity of 3 consecutive sections/individual + SEM is shown for each subject/condition. Group differences and statistical significance was determined using one-way ANOVA with Tukey post hoc analysis