Journal: JCI Insight
Article Title: Blocking IL-6 signaling prevents astrocyte-induced neurodegeneration in an iPSC-based model of Parkinson’s disease
doi: 10.1172/jci.insight.163359
Figure Lengend Snippet: ( A ) Representative immunocytochemistry (ICC) images of CTL (SP09) and L2-PD astrocytes (SP13) expressing DAPI (blue) and GFAP (green) after 14 days in culture. Scale bar: 100 μm. CTL astrocytes (SP09) treated for 48 hours with C1q, TNF-α, and IL-1α were used as positive control (CTL+CS). Images on the right show a magnification of the area boxed in the left images. Scale bar: 10 μm. Yellow arrowheads indicate high GFAP staining in hypertrophic astrocytes. ( B ) Mean intensity of GFAP staining. ( C ) Form factor of GFAP + cells calculated as: FF = 4 Pi number (π) (area/perimeter 2 ). ( D ) Representative ICC images of CTL, L2-PD, and activated CTL astrocytes expressing Vimentin (CTL: SP09; L2-PD: SP13), AQP4 (CTL: SP17; L2-PD: SP06), and C3 (CTL: SP09; L2-PD: SP13). Scale bar: 100 μm. Images on the right show a magnification of the area boxed in the left images. Scale bar: 10 μm. Yellow arrowheads indicate high expression of the specific marker shown in the images. ( E ) Mean intensity of C3 staining with respect to CTL. ( F ) Relative mRNA expression of panreactive, A1-specific and A2-specific transcripts in L2-PD astrocytes with respect to CTL. Box-and-whisker plots show median, 25th and 75th percentiles, minimum, and maximum values ( n = 3 experiments; form factor, mean GFAP, and C3 intensity were performed from 30 astrocytes per experiment per condition). One-way ANOVA was used, with Bonferroni as post hoc. * P < 0.05; ** P < 0.01; *** P < 0.001. ( G ) Heatmap of differentially expressed genes (DEG) of CTL and L2-PD astrocytes. ( H ) Enrichment plot showing the enrichment score for the selected GO BP gene sets (e.g., antigen processing and presentation of exogenous peptide antigen via MHC class II, B cell mediated immunity, complement activation, humoral immune response mediated by circulating immunoglobulin, immunoglobulin production, negative regulation of neuron differentiation, peptide antigen assembly with MHC protein complex, response to IL-6).
Article Snippet: Antibodies used were: rabbit polyclonal antibodies against IL-6 (Abcam, ab6672) diluted 1:100; rabbit polyclonal anti–IL-6R (R&D Systems, MAB2271) diluted at 1:50; anti-GFAP antibody (Diagnostic BioSystems, Mob064) diluted at 1:1,000, and rabbit anti-TH (MilliporeSigma, T8700) diluted 1:100.
Techniques: Immunocytochemistry, Expressing, Positive Control, Staining, Marker, Whisker Assay, Activation Assay