title: Quantitative neuroanatomy of all Purkinje cells with light sheet microscopy and high-throughput image analysis.
abstract: Characterizing the cytoarchitecture of mammalian central nervous system on a brain-wide scale is becoming a compelling need in neuroscience. For example, realistic modeling of brain activity requires the definition of quantitative features of large neuronal populations in the whole brain. Quantitative anatomical maps will also be crucial to classify the cytoarchtitectonic abnormalities associated with neuronal pathologies in a high reproducible and reliable manner. In this paper, we apply recent advances in optical microscopy and image analysis to characterize the spatial distribution of Purkinje cells (PCs) across the whole cerebellum. Light sheet microscopy was used to image with micron-scale resolution a fixed and cleared cerebellum of an L7-GFP transgenic mouse, in which all PCs are fluorescently labeled. A fast and scalable algorithm for fully automated cell identification was applied on the image to extract the position of all the fluorescent PCs. This vectorized representation of the cell population allows a thorough characterization of the complex three-dimensional distribution of the neurons, highlighting the presence of gaps inside the lamellar organization of PCs, whose density is believed to play a significant role in autism spectrum disorders. Furthermore, clustering analysis of the localized somata permits dividing the whole cerebellum in groups of PCs with high spatial correlation, suggesting new possibilities of anatomical partition. The quantitative approach presented here can be extended to study the distribution of different types of cell in many brain regions and across the whole encephalon, providing a robust base for building realistic computational models of the brain, and for unbiased morphological tissue screening in presence of pathologies and/or drug treatments.
authors.affiliation: National Institute of Optics, National Research Council Sesto Fiorentino, Italy ; European Laboratory for Non-Linear Spectroscopy Sesto Fiorentino, Italy.
authors.forename: Ludovico
authors.initials: L
authors.lastname: Silvestri
authors.affiliation: Department of Information Engineering, University of Florence Florence, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Paciscopi
authors.affiliation: Department of Engineering, University Campus Bio-Medico of Rome Rome, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Soda
authors.affiliation: Institute of Histology and Embryology, Catholic University of the Sacred Heart "A. Gemelli", Rome Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Biamonte
authors.affiliation: Department of Engineering, University Campus Bio-Medico of Rome Rome, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Iannello
authors.affiliation: European Laboratory for Non-Linear Spectroscopy Sesto Fiorentino, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Frasconi
authors.affiliation: National Institute of Optics, National Research Council Sesto Fiorentino, Italy ; European Laboratory for Non-Linear Spectroscopy Sesto Fiorentino, Italy ; Department of Physics and Astronomy, University of Florence Sesto Fiorentino, Italy ; International Center for Computational Neurophotonics Sesto Fiorentino, Italy.
authors.forename: Francesco S
authors.initials: FS
authors.lastname: Pavone
keywords: Purkinje cells; brain imaging; cerebellum; image analysis; light sheet microscopy; quantitative neuroanatomy