For long time microglia have been considered quiescent cells, activated only in cases of infections or threats to the brain homeostasis. However, the literature over the past decades has literally revolutionized this view, introducing a new definition, ‘surveying microglia’ as opposed to ‘resting’, to pinpoint constantly active cells, continuously monitoring the brain parenchyma and the synaptic function. In particular, during early brain development, several studies have revealed a critical role for microglia as shapers of neural circuits, by providing trophic factors, and by remodeling and pruning synapses.
Schematic representation of the possible mechanisms mediating synapse loss by microglia. From Rajendran and Paolicelli, Journal of Neurosci 2018.
Interestingly, synapse loss is the major correlate of cognitive impairment in many neurodegenerative diseases. Recent literature suggests that microglia, which mediate synaptic pruning during brain development, can be responsible for synapse loss in neurodegeneration. Although the underlying mechanisms are poorly understood, growing evidence indicates that dysfunctional microglia affect synapses number and function in pathology. Genome-wide association studies reveal that the majority of risk genes associated with neurodegenerative disorders are highly expressed in microglia. However, while such studies clearly implicate these cells in the pathogenesis of the disease, little is still known about the causal mechanisms that link microglial risk variants to loss of synapses.
Background from left to right: Elsa Hoti, Kyllian Ginggen, Anne-Claire Compagnion, Alessandro Matera, Anastasija Milentijevic, Nathalie Stefanoni
Foreground from left to right: Fanny Martineau, Evangelina Christoforidi, Rosa Chiara Paolicelli, An Buckinx, Katia Monsorno
Rosa Chiara Paolicelli, Assistant Professor
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Rosa C. Paolicelli earned her bachelor of Medical Biotechnology at the University of Bologna, Italy, in 2006, and her MSc in Molecular Neuroscience at the University of Bristol, UK, in 2007. She graduated in 2011 with a PhD in Cellular and Molecular Biology, from the European Molecular Biology Laboratory (EMBL), where she investigated the role of microglia in refining neural circuits during development. After completing her PhD, Dr. Paolicelli worked as postdoc at the University of Zurich, Switzerland, in the Department of Systems and Cell Biology of Neurodegeneration (2012-2018). During this time, she studied the cellular and molecular mechanisms underlying microglia-mediated synapse loss in neurodegenerative diseases, by using a combination of in vitro and in vivo approaches. In 2018 Dr. Paolicelli got a position as Assistant Professor at the Department of Physiology, University of Lausanne, where she established her lab on microglia biology, focusing on the molecular mechanisms regulating microglia-synapse interaction in physiological and pathological contexts. She recently obtained an ERC starting grant to investigate the role of microglia in neurodegeneration. |
Katia Monsorno, Lab Manager
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Katia obtained her Bachelor's and Master's degrees in Molecular Biology from the University of Trento (Italy), where she specialized in Neurobiology. Her scientific interests primarily lie in glial cell physiology and how their alterations could lead to the onset of neuropathology. During her Master's thesis, she worked to elucidate the effects of several inflammatory factors on astrocyte metabolism, as well as the roles played by microglia in establishing this regulation. She joined Rosa Chiara Paolicelli's group as a PhD student in 2019 to study the modulation exerted by lactate on microglia in the context of brain development. She has now completed her PhD and continues to work in the lab as a Lab Manager, providing organizational and technical support to other lab members while continuing to investigate the metabolic control of microglia. |
Grégoire Bena, Intern
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Grégoire obtained his bachelor’s degree in biology from the University of Lausanne. In March 2024, he began an internship in Rosa Chiara Paolicelli’s lab, prior to starting his master’s degree in medical biology at the University of Lausanne in September. Throughout his internship, he will immerse himself in the lab environment while helping other team members, specifically focusing on the molecular mechanisms underlying microglia-mediated synapse loss in pathology. |
Giulia Borgonovo, guest researcher
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Giulia Borgonovo is currently a Ph.D. candidate in Neuroscience at the Scuola Normale Superiore in Pisa (Italy), conducting research in Prof. Antonino Cattaneo's laboratory, and a visiting Ph.D. student in Paolicelli Lab. Her ongoing research project focuses on unraveling the complex interplay between neurotrophins and microglia, from molecular and cellular viewpoints, both in physiological and pathological conditions. Giulia earned her bachelor's degree in Biotechnology at the University of Genoa (Italy), where she investigated the interactions of platinum nanoparticles with cortical neurons in Prof. Fabio Benfenati's lab at the Italian Institute of Technology. She then pursued her master's degree in Neuroscience at the University of Pisa and, simultaneously, engaged in a Second Level Master's program in Neurobiology at the Scuola Normale Superiore. Her master's project explored the effects of an NGF-based treatment on astrocytes in Rett syndrome mouse models. |
Iucy Bruguiere, Intern
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Lucy Bruguière is currently studying for her Bachelor’s degree in Bioscience, Biotechnology and Management at the University of Leeds, in England. As part of her degree program, for her 3rd year she is doing an industry placement, half of which was at the DNF Unil, in Ludovic Telley’s lab, where she worked on cerebellar development. She moved to Rosa Chiara Paolicelli’s lab in January 2024 for the second half of her placement. There she will continue to develop her lab skills while working on microglia and their main properties in the mouse brain. |
Gloria Colombo, Postdoc
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Gloria Colombo obtained a BSc in molecular biotechnology and a MSc in neurobiology at the University of Pavia, in Italy. In 2016, she joined the graduate school program at the institute of Science and Technology Austria (ISTA) and affiliated to Prof Siegert’s group. Her PhD project aimed at developing a new algorithm to analyze the impact of region and sex on microglial morphology in health and disease and to map microglial morphology from regions of interest. After obtaining her PhD, she started her postdoc in the Paolicelli’s group, where she works to dissect the contribution of microglial lactate metabolism in ischemic stroke. |
Anne-Claire Compagnion, Postdoc
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Anne-Claire followed her studies at Sorbonne University in Paris, France, where she obtained her bachelor in Life Sciences and her master degree in Neurosciences. In 2015, she joined the group of Dr.Tronche in the Institut de Biologie Paris-Seine, Sorbonne University where she started her PhD under the supervision of Dr. Vyas. For four years, she studied the differential impact of alpha-synuclein assemblies on microglial reactivity. She obtained her PhD in 2019, and stayed to study the involvement of transcription factors in social and addictive behavior. Since March 2021, she is a post-doctoral researcher in the Paolicelli’s group focusing her work on the molecular and cellular mechanisms of microglia-mediated synapse loss in neurodegeneration. |
Kyllian Ginggen, PhD student
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Kyllian obtained his bachelor’s degree in biology and his master’s degree in medical biology at the University of Lausanne. During his master’s degree, he decided to focus on neuroscience, especially on glial cells. For his master thesis, he aimed to disrupt basolateral amygdala astrocytes activity by using chemogenetics to prevent the association of cocaine hedonic behavior to its environmental associated cue. In May 2019, he started a Ph.D. in the team of professor Paolicelli, focusing on the function of microglia in synapse plasticity, both in physiological and pathological contexts
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Fanny Martineau, Postdoc
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Fanny studied at Aix-Marseille University in France where she earned her bachelor in Biology and her master degree in Developmental Biology, Immunology and Neurobiology. In 2013, she joined Dr. A. Represa’s group at the Mediterranean Institute for Neurobiology (Marseille, France) to start her PhD in Neurosciences under the joint supervision of Dr. JB. Manent and F. Watrin. For four years, she investigated how laminar misplacement resulting from neuronal migration failure in the cortex influences neuronal maturation and overall rat behavior. She graduated in November 2017 and temporarily joined Dr. V. Crépel’s lab to work on pathological kainate synapses in the context of temporal lobe epilepsy. Fanny moved to Dr. R. C. Paolicelli’s lab in July 2019 to investigate the molecular mechanisms underlying microglia-mediated synapse loss in pathology. |
Pierre-Hugues Prouvot Bouvier, Postdoc
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Pierre-Hugues started his studies at Paris Descartes university (Paris-Cité) with a bachelor’s in biomedical studies followed by a Master's degree in Cellular Biology with a Neuroscience specialization. During an extended internship with Dr. Brandon Stell in the lab of Prof. Alain Marty he got interested electrophysiology and optical physiology using it to study lateral connectivity of molecular layer interneurons in the cerebellum. He then transferred to the Johannes Gutenberg university in Mainz for his PhD in the lab of Prof. Albrecht Stroh to study PV interneurons in the barrel cortex combining multi-electrode Arrays in vivo with optogenetics in collaboration with the group of Prof. Luhmann. In parallel he worked on establishing in vivo awake two-photon calcium imaging and optogenetics in partnership with LaVision Biotec. In 2021 he joined the DSB in the Group of Prof. Tafti for two years, investigating the importance of the cholinergic system in REM sleep using fiber photometry fluorescent GRAB sensors. He then joined the group of Prof. Paolicelli to use electrophysiology in the study of microglia-mediated neuronal network remodeling in vivo. |
Filipe Teixeira, Research technician
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Filipe obtained his BSc in Biology and MSc in Human Biology and Environment at the Sciences Faculty of Lisbon University, in Portugal. During the master he decided to specialize in biomedicine. His master thesis consisted in studying the regeneration process of starfish central nervous system at the molecular, cellular and tissue levels. After completing his masters, he earned a fellowship to study the infection process and host-microbiome interaction of a pathogenic skin bacteria and an artificial human skin model. In February 2024, he joined DR. Prof Paolicelli’ lab to study the effect of a novel SHIP1 agonist compound in microglia. |
Alumni
Alessandro Matera, PhD student
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Alessandro obtained the Bachelor degree in Biological Sciences at “La Sapienza”, University of Rome. He continued his studies earning the Master degree in Neurobiology. He worked on physiological and developmental processes of Schwann cells involved in the axonal regeneration. Now, he is a PhD in Prof. Paolicelli’s laboratory, working on microglia biology, focusing on microglia-synapse interaction. |
