title: New tools for studying microglia in the mouse and human CNS.
abstract: The specific function of microglia, the tissue resident macrophages of the brain and spinal cord, has been difficult to ascertain because of a lack of tools to distinguish microglia from other immune cells, thereby limiting specific immunostaining, purification, and manipulation. Because of their unique developmental origins and predicted functions, the distinction of microglia from other myeloid cells is critically important for understanding brain development and disease; better tools would greatly facilitate studies of microglia function in the developing, adult, and injured CNS. Here, we identify transmembrane protein 119 (Tmem119), a cell-surface protein of unknown function, as a highly expressed microglia-specific marker in both mouse and human. We developed monoclonal antibodies to its intracellular and extracellular domains that enable the immunostaining of microglia in histological sections in healthy and diseased brains, as well as isolation of pure nonactivated microglia by FACS. Using our antibodies, we provide, to our knowledge, the first RNAseq profiles of highly pure mouse microglia during development and after an immune challenge. We used these to demonstrate that mouse microglia mature by the second postnatal week and to predict novel microglial functions. Together, we anticipate these resources will be valuable for the future study and understanding of microglia in health and disease.
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305; marikobennett@stanford.edu barres@stanford.edu.
authors.forename: Mariko L
authors.identifier: http://orcid.org/0000-0002-1642-2887
authors.initials: ML
authors.lastname: Bennett
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305; Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305;
authors.forename: F Chris
authors.initials: FC
authors.lastname: Bennett
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305; Department of Pharmacology and Therapeutics, University of Melbourne, Melbourne, VIC, Australia, 3010;
authors.forename: Shane A
authors.initials: SA
authors.lastname: Liddelow
authors.affiliation: Department of Neurology, Stanford University School of Medicine, Stanford, CA 94305;
authors.forename: Bahareh
authors.initials: B
authors.lastname: Ajami
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305;
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Zamanian
authors.affiliation: Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305; Ludwig Center for Cancer Stem Cell Research and Medicine, Stanford University School of Medicine, Stanford, CA 94305; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305; Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305;
authors.forename: Nathaniel B
authors.initials: NB
authors.lastname: Fernhoff
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305;
authors.forename: Sara B
authors.initials: SB
authors.lastname: Mulinyawe
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305;
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Bohlen
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305;
authors.forename: Aykezar
authors.initials: A
authors.lastname: Adil
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305;
authors.forename: Andrew
authors.initials: A
authors.lastname: Tucker
authors.affiliation: Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305; Ludwig Center for Cancer Stem Cell Research and Medicine, Stanford University School of Medicine, Stanford, CA 94305; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA 94305; Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305;
authors.forename: Irving L
authors.initials: IL
authors.lastname: Weissman
authors.affiliation: University of California, San Francisco Epilepsy Center, University of California, San Francisco, CA 94143;
authors.forename: Edward F
authors.initials: EF
authors.lastname: Chang
authors.affiliation: Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305.
authors.forename: Gordon
authors.initials: G
authors.lastname: Li
authors.affiliation: Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305.
authors.forename: Gerald A
authors.initials: GA
authors.lastname: Grant
authors.affiliation: Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305.
authors.forename: Melanie G
authors.initials: MG
authors.lastname: Hayden Gephart
authors.affiliation: Department of Neurobiology, Stanford University School of Medicine, Stanford, CA 94305; marikobennett@stanford.edu barres@stanford.edu.
authors.forename: Ben A
authors.initials: BA
authors.lastname: Barres
mesh_terms: D000368:Aged; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015415:Biomarkers; D001921:Brain / Q000166:cytology* / Q000196:embryology / Q000254:growth & development; D002455:Cell Division; D019070:Cell Lineage; D002648:Child; D019446:Endotoxemia / Q000473:pathology; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D008070:Lipopolysaccharides / Q000633:toxicity; D008264:Macrophages / Q000737:chemistry; D008565:Membrane Proteins / Q000032:analysis* / Q000172:deficiency / Q000235:genetics / Q000276:immunology; D051379:Mice; D018345:Mice, Knockout; D017628:Microglia / Q000737:chemistry* / Q000502:physiology; D008875:Middle Aged; D009409:Nerve Crush; D009419:Nerve Tissue Proteins / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D020221:Optic Nerve Injuries / Q000473:pathology; D009928:Organ Specificity; D011817:Rabbits; D012584:Sciatic Nerve / Q000293:injuries / Q000473:pathology; D017423:Sequence Analysis, RNA; D013702:Temporal Lobe / Q000378:metabolism; D059467:Transcriptome
chemical_list: D000911:Antibodies, Monoclonal; D015415:Biomarkers; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C547179:Obif protein, mouse; C000609850:Tmem119 protein, human
keywords: RNAseq; developmental neuroscience; glia; macrophage; microglia