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bioRxiv · 10.1101/2022.05.05.490765

GliaMorph: A modular image analysis toolkit to quantify Müller glial cell morphology

Abstract

Cell morphology is critical for all cell functions. This is particularly true for glial cells as they rely on their complex shape to contact and support neurons. However, methods to quantify complex glial cell shape accurately and reproducibly are lacking. To address this gap in quantification approaches, we developed an analysis pipeline called "GliaMorph". GliaMorph is a modular image analysis toolkit developed to perform (i) image pre-processing, (ii) semi-automatic region-of-interest (ROI) selection, (iii) apicobasal texture analysis, (iv) glia segmentation, and (v) cell feature quantification. Muller Glia (MG) are the principal retinal glial cell type with a stereotypic shape linked to their maturation and physiological status. We here characterized MG on three levels, including (a) global image-level, (b) apicobasal texture, and (c) apicobasal vertical-to-horizontal alignment. Using GliaMorph, we show structural changes occurring in the developing retina. Additionally, we study the loss of cadherin2 in the zebrafish retina, as well as a glaucoma mouse disease model. The GliaMorph toolkit enables an in-depth understanding of MG morphology in the developing and diseased retina. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=144 HEIGHT=200 SRC="FIGDIR/small/490765v1_ufig1.gif" ALT="Figure 1"> View larger version (73K): org.highwire.dtl.DTLVardef@198fca6org.highwire.dtl.DTLVardef@f319fcorg.highwire.dtl.DTLVardef@2f0fadorg.highwire.dtl.DTLVardef@1ae4ce7_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LIGlial morphology is complex, making it challenging to accurately quantify 3D cell shape. C_LIO_LIWe developed the GliaMorph toolkit for image pre-processing, glial segmentation, and quantification of Muller glial cells. C_LIO_LIMuller glia elaborate their morphology and rearrange subcellular features during embryonic development. C_LIO_LIGliaMorph accurately identifies subcellular changes in models with disrupted glia cells, including zebrafish cadherin2 loss of function and a mouse glaucoma model. C_LI

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BibTeXRIS

Kugler, E. C., Bravo, I., Durmishi, X., Marcotti, S., Beqiri, S., Carrington, A., Stramer, B. C., Mattar, P., MacDonald, R. B.. 2022-05-05. GliaMorph: A modular image analysis toolkit to quantify Müller glial cell morphology. https://doi.org/10.1101/2022.05.05.490765

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