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Wang, E. Y.

Publications and source records attributed to Wang, E. Y..

4 recordsLinked to original sources

A type I interferon response defines a conserved microglial state required for effective phagocytosis

Microglia are brain resident phagocytes that can engulf synaptic components and extracellular matrix as well as whole neurons. However, whether there are unique molecular mechanisms that regulate these distinct phagocytic states is unknown. Here we define a molecularly distinct microglial subset whose function is to engulf neurons in the developing brain. We transcriptomically identified a cluster of Type I interferon (IFN-I) responsive microglia that expanded 20-fold in the postnatal day 5 somatosensory cortex after partial whisker deprivation, a stressor that accelerates neural circuit remodeling. In situ, IFN-I responsive microglia were highly phagocytic and actively engulfed whole neurons. Conditional deletion of IFN-I signaling (Ifnar1fl/fl) in microglia but not neurons resulted in dysmorphic microglia with stalled phagocytosis and an accumulation of neurons with double strand DNA breaks, a marker of cell stress. Conversely, exogenous IFN-I was sufficient to drive neuronal engulfment by microglia and restrict the accumulation of damaged neurons. IFN-I deficient mice had excess excitatory neurons in the developing somatosensory cortex as well as tactile hypersensitivity to whisker stimulation. These data define a molecular mechanism through which microglia engulf neurons during a critical window of brain development. More broadly, they reveal key homeostatic roles of a canonical antiviral signaling pathway in brain development.

neuroscience

A human brain vascular atlas reveals diverse cell mediators of Alzheimer's disease risk

The human brain vasculature is of vast medical importance: its dysfunction causes disability and death, and the specialized structure it forms--the blood-brain barrier--impedes treatment of nearly all brain disorders. Yet, no molecular atlas of the human brain vasculature exists. Here, we develop Vessel Isolation and Nuclei Extraction for Sequencing (VINE-seq) to profile the major human brain vascular and perivascular cell types through 143,793 single-nucleus transcriptomes from 25 hippocampus and cortex samples of 17 control and Alzheimers disease (AD) patients. We identify brain region-enriched pathways and genes divergent between humans and mice, including those involved in disease. We describe the principles of human arteriovenous organization, recapitulating a gradual endothelial and punctuated mural cell continuum; but discover that many zonation and cell-type markers differ between species. We discover two subtypes of human pericytes, marked by solute transport and extracellular matrix (ECM) organization; and define perivascular versus meningeal fibroblast specialization. In AD, we observe a selective vulnerability of ECM-maintaining pericytes and gene expression patterns implicating dysregulated blood flow. With an expanded survey of brain cell types, we find that 30 of the top 45 AD GWAS genes are expressed in the human brain vasculature, confirmed in situ. Vascular GWAS genes map to endothelial protein transport, adaptive immune, and ECM pathways. Many are microglia-specific in mice, suggesting an evolutionary transfer of AD risk to human vascular cells. Our work unravels the molecular basis of the human brain vasculature, informing our understanding of overall brain health, disease, and therapy.

neuroscience

REAP: A platform to identify autoantibodies that target the human exoproteome

Autoantibodies that recognize extracellular proteins (the "exoproteome") exert potent biological effects but have proven challenging to detect with existing screening technologies. Here, we developed Rapid Extracellular Antigen Profiling (REAP) as a technique for comprehensive, high-throughput discovery of exoproteome-targeting autoantibodies. With REAP, patient samples are applied to a genetically-barcoded library containing 2,688 human extracellular proteins displayed on the surface of yeast. Antibody-coated cells are isolated by magnetic selection and deep sequencing of their barcodes is used to identify the displayed antigens. To benchmark the performance of REAP, we screened 77 patients with autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED). REAP sensitively and specifically detected known autoantibody reactivities in APECED in addition to numerous previously unidentified reactivities. We further screened 106 patients with systemic lupus erythematosus (SLE) and identified novel autoantibody reactivities against a diverse set of antigens including growth factors, extracellular matrix components, cytokines, and immunomodulatory proteins. Several of these responses were associated with disease severity and specific clinical manifestations of SLE and exerted potent functional effects on cell signaling ex vivo. These findings demonstrate the utility of REAP to atlas the expansive landscape of exoproteome-targeting autoantibodies and their impacts on patient health outcomes.

immunology

Cellular expression and functional roles of all 26 neurotransmitter GPCRs in the C. elegans egg-laying circuit

Maps of the synapses made and neurotransmitters released by all neurons in model systems such as C. elegans have left still unresolved how neural circuits integrate and respond to neurotransmitter signals. Using the egg-laying circuit of C. elegans as a model, we mapped which cells express each of the 26 neurotransmitter G protein coupled receptors (GPCRs) of this organism and also genetically analyzed the functions of all 26 GPCRs. We found that individual neurons express many distinct receptors, epithelial cells often express neurotransmitter receptors, and receptors are often positioned to receive extrasynaptic signals. The egg-laying circuit appears to use redundancy and compensation to achieve functional robustness, as receptor knockouts reveal few defects; however, increasing receptor signaling through overexpression more efficiently reveals receptor functions. This map of neurotransmitter GPCR expression and function in the egg-laying circuit provides a model for understanding GPCR signaling in other neural circuits.

neuroscience