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bioRxiv · 10.1101/2022.05.09.491159

Quantification of astrocytic synaptic pruning in hippocampus in response to in vitro Aβ oligomer incubation via colocalization analysis with C1q

Pradhan, A. K.·Shi, Q.·Tartler, K. J.·Rammes, G.
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Abstract

Quantification of synaptic engulfment is an indirect measurement of synaptic pruning. Here, we provide a detailed protocol for the volumetric rendering of individual high-resolution astrocytes in the CA1 region of hippocampus in an in vitro slice model of Amyloid-beta (A{beta}) treatment. This includes free floating slice preparation, treatment with A{beta} oligomers, immunofluorescence, confocal imaging and analysis of individual astrocytes. We also provide a comprehensive analysis for 3D rendering of astrocytes and assessment of synaptic engulfment via "eat-me tag" C1q protein and synaptic marker PSD95. HighlightsO_LIMeasurement of synaptic engulfment in response to treatment with A{beta} peptide C_LIO_LIVolumetric reconstruction of high resolution individual astrocyte C_LIO_LIColocalization analysis of astrocyte and complementary "eat-me" protein C1q C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=193 SRC="FIGDIR/small/491159v1_ufig1.gif" ALT="Figure 1"> View larger version (54K): org.highwire.dtl.DTLVardef@17d70b6org.highwire.dtl.DTLVardef@72db3dorg.highwire.dtl.DTLVardef@97968aorg.highwire.dtl.DTLVardef@1c447b_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Pradhan, A. K., Shi, Q., Tartler, K. J., Rammes, G.. 2022-05-12. Quantification of astrocytic synaptic pruning in hippocampus in response to in vitro Aβ oligomer incubation via colocalization analysis with C1q. https://doi.org/10.1101/2022.05.09.491159

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