OUR SCIENCE

Publications

2024

Cell

Microglial-derived C1q integrates into neuronal ribonucleoprotein complexes and impacts protein homeostasis in the aging brain

Scott-Hewitt N, Mahoney M, Huang Y, Korte N, Yvanka de Soysa T, Wilton DK, Knorr E, Mastro K, Chang A, Zhang A, Melville D, Schenone M, Hartigan C, Stevens B

Cell. 2024 Jun; S0092-8674(24)00639-1. DOI: 10.1016/j.cell.2024.05.058

Brain Behav Immun

CSMD1 regulates brain complement activity and circuit development

Baum ML, Wilton DK, Fox RG, Carey A, Hsu YH, Hu R, Jäntti HJ, Fahey JB, Muthukumar AK, Salla N, Crotty W, Scott-Hewitt N, Bien E, Sabatini DA, Lanser TB, Frouin A, Gergits F, Håvik B, Gialeli C, Nacu E, Lage K, Blom AM, Eggan K, McCarroll SA, Johnson MB, Stevens B

Brain Behav Immun. 2024 Jul; 119:317-332. DOI: 10.1016/j.bbi.2024.03.041

2023

Brain, Behavior, and Immunity

Spatial enrichment of the type 1 interferon signature in the brain of a neuropsychiatric lupus murine model

Aw E, Zhang Y, Yalcin E, Herrmann U, Lin SL, Langston K, Castrillon C, Ma M, Moffitt JR, Carroll MC

Brain Behav Immun. 2023 Nov; 114: 511-522. DOI: 10.1016/j.bbi.2023.06.021

Nature Medicine

Microglia and complement mediate early corticostriatal synapse loss and cognitive dysfunction in Huntington’s disease

Wilton DK, Mastro K, Heller MD, Gergits FW, Willing CR, Fahey JB, Frouin A, Daggett A, Gu X, Kim YA, Faull RLM, Jayadev S, Yednock T, Yang XW, Stevens B

Nat Med. 2023 Nov; 29 (11): 2866-2884. DOI: 10.1038/s41591-023-02566-3

Nature Communication

FEAST: A flow cytometry-based toolkit for interrogating microglial engulfment of synaptic and myelin proteins

Dissing-Olesen L, Walker AJ, Feng Q, Barr HJ, Walker AC, Xie L, Wilton DK, Das I, Benowitz LI, Stevens B

Nat Commun. 2023 Sep 27; 14: 6015. DOI: 10.1038/s41467-023-41448-7

Nature

Bacteria hijack a meningeal neuroimmune axis to facilitate brain invasion

Pinho-Ribeiro FA, Deng L, Neel DV, Erdogan O, Basu H, Yang D, Choi S, Walker AJ, Carneiro-Nascimento S, He K, Wu G, Stevens B, Doran KS, Levy D, Chiu IM

Nature. 2023 Mar; 615 (7952): 472-481. DOI: 10.1038/s41586-023-05753-x

Stem Cell Reports

Small-molecule screen reveals pathways that regulate C4 secretion in stem cell-derived astrocytes

Rapino F, Natoli T, Limone F, O’Connor E, Blank J, Tegtmeyer M, Chen W, Norabuena E, Narula J, Hazelbaker D, Angelini G, Barrett L, O’Neil A, Beattie UK, Thanos JM, de Rivera H, Sheridan SD, Perlis RH, McCarroll SA, Stevens B, Subramanian A, Nehme R, Rubin LL

Stem Cell Reports. 2023 Jan; 18 (1): 237-253. DOI: 10.1016/j.stemcr.2022.11.018

2021

Advances in Immunology

Neuropsychiatric disorders: An immunological perspective

Aw E, Zhang Y, Yalcin E, Herrmann US, Carroll MC

Adv Immunol. 2021 Nov; 152: 83-155. DOI: 10.1016/bs.ai.2021.09.002

Nature Neuroscience 

Overexpression of schizophrenia susceptibility factor human complement C4A promotes excessive synaptic loss and behavioral changes in mice

Yilmaz M, Yalcin E, Presumey J, Aw E, Ma M, Whelan CW, Stevens B, McCarroll SA, Carroll MC

This paper presents a comprehensive analysis of the impact of human C4A and C4B expression and dosage effects in humanized mouse models. hC4A and hC4B display differences in synaptic tagging and downstream phenotypes, consistent with the differential schizophrenia risk profile of these isotypes. Overexpression of hC4A results in increased synaptic pruning by microglia, altered circuit development, and changes in behavior. These results strongly support a role for neuroimmune mechanisms in prefrontal circuit development and psychiatric vulnerability, and advance the pruning hypothesis of schizophrenia.

Nat Neurosci. 2021 Feb; 24 (2): 214-224. DOI: 10.1038/s41593-020-00763-8

2020

Journal of Immunology

A Complement C3-Specific Nanobody for Modulation of the Alternative Cascade Identifies the C-Terminal Domain of C3b as Functional in C5 Convertase Activity

Pedersen H, Jensen RK, Jensen JMB, Fox R, Pedersen DV, Olesen HG, Hansen AG, Christiansen D, Mazarakis SMM, Lojek N, Hansen P, Gadeberg TAF, Zarantonello A, Laursen NS, Mollnes TE, Johnson MB, Stevens B, Thiel S, Andersen GR

J Immunol. 2020 Oct 15; 205 (8): 2287-2300. DOI: 10.4049/jimmunol.2000752

Trends in Immunology

Microglia and Astrocytes in Disease: Dynamic Duo or Partners in Crime?

Liddelow SA, Marsh SE, Stevens B

Trends Immunol. 2020 Sep; 41 (9): 820-835. DOI: 10.1016/j.it.2020.07.006

Journal of Immunology

An Ultrahigh-Affinity Complement C4b-Specific Nanobody Inhibits In Vivo Assembly of the Classical Pathway Proconvertase

Zarantonello A, Presumey J, Simoni L, Yalcin E, Fox R, Hansen A, Olesen HG, Thiel S, Johnson MB, Stevens B, Laursen NS, Carroll MC, Andersen GR

J Immunol. 2020 Sep 15; 205 (6): 1678-1694. DOI: 10.4049/jimmunol.2000528

The EMBO Journal

Local Externalization of Phosphatidylserine Mediates Developmental Synaptic Pruning by Microglia

Scott-Hewitt N, Perrucci F, Morini R, Erreni M, Mahoney M, Witkowska A, Carey A, Faggiani E, Schuetz LT, Mason S, Tamborini M, Bizzotto M, Passoni L, Filipello F, Jahn R, Stevens B, Matteoli M

This paper describes regulation and consequences of phosphatidylserine exposure on neuronal and synaptic membranes, which may serve to recruit or regulate complement activity at synapses and their downstream phagocytosis by microglia.

EMBO J. 2020 Aug 17;39(16):e105380. DOI: 10.15252/embj.2020105380

Nature

Complement Genes Contribute Sex-Biased Vulnerability in Diverse Disorders

Kamitaki N, Sekar A, Handsaker RE, de Rivera H, Tooley K, Morris DL, Taylor KE, Whelan CW, Tombleson P, Loohuis LMO; Schizophrenia Working Group of the Psychiatric Genomics Consortium; Boehnke M, Kimberly RP, Kaufman KM, Harley JB, Langefeld CD, Seidman CE, Pato MT, Pato CN, Ophoff RA, Graham RR, Criswell LA, Vyse TJ, McCarroll SA

This paper elucidates the differential risk profiles arising from C4 locus genetic variation for men and women, and the complex relationships between C4A-related risk for schizophrenia versus autoimmune disorders such as lupus. The McCarroll lab also presents here foundational data on complement component C3 and C4 protein levels in the CSF across the lifespan of healthy adults, demonstrating that sex and age effects, in addition to C4 genotype, are highly significant covariates in any consideration of complement as fluid biomarkers. Finally, this paper also describes a computational method and data resource for imputing C4 genotypes from SNP data, which will be highly useful in a variety of research and translational contexts considering the complex influence of C4 variation on complement expression and disease risk.

Nature. 2020 Jun;582(7813):577-581. DOI: 10.1038/s41586-020-2277-x

2019

Immunity

Single-Cell RNA Sequencing of Microglia throughout the Mouse Lifespan and in the Injured Brain Reveals Complex Cell-State Changes

Hammond TR, Dufort C, Dissing-Olesen L, Giera S, Young A, Wysoker A, Walker AJ, Gergits F, Segel M, Nemesh J, Marsh SE, Saunders A, Macosko E, Ginhoux F, Chen J, Franklin RJM, Piao X, McCarroll SA, Stevens B

We analyzed the RNA expression patterns of more than 76,000 individual microglia in mice during development, in old age, and after brain injury. Our analysis uncovered at least nine transcriptionally distinct microglial states, which expressed unique sets of genes and were localized in the brain using specific markers.

Immunity. 2019 Jan 15;50(1):253-271.e6. DOI: 10.1016/j.immuni.2018.11.004

2018

Neuron

CD47 Protects Synapses from Excess Microglia-Mediated Pruning during Development

Lehrman EK, Wilton DK, Litvina EY, Welsh CA, Chang ST, Frouin A, Walker AJ, Heller MD, Umemori H, Chen C, Stevens B

Here, we demonstrate that an innate immune signaling pathway protects synapses from inappropriate removal. The expression patterns of CD47 and its receptor, SIRPα, correlated with peak pruning in the developing retinogeniculate system, and mice lacking these proteins exhibited increased microglial engulfment of retinogeniculate inputs and reduced synapse numbers in the dorsal lateral geniculate nucleus. In addition, CD47 was found to be required for neuronal activity-mediated changes in engulfment, as microglia in CD47 knockout mice failed to display preferential engulfment of less active inputs.

Neuron. 2018 Oct 10;100(1):120-134.e6. DOI: 10.1016/j.neuron.2018.09.017

Annual Review of Cell and Developmental Biology

Microglia and the Brain: Complementary Partners in Development and Disease

Hammond TR, Robinton D, Stevens B.

In this review, we discuss the crucial roles that microglia play in shaping the brain – from their influence on neurons and glia within the developing CNS to their roles in synaptic maturation and brain wiring – as well as some of the obstacles to overcome when assessing their contributions to normal brain development. Furthermore, we examine how normal developmental functions of microglia are perturbed or remerge in neurodevelopmental and neurodegenerative disease.

Annu Rev Cell Dev Biol. 2018 Oct 6:34:523-544. DOI: 10.1146/annurev-cellbio-100616-060509

2016

Nature

Schizophrenia risk from complex variation of complement component 4

Sekar A, Bialas AR, de Rivera H, Davis A, Hammond TR, Kamitaki N, Tooley K, Presumey J, Baum M, Van Doren V, Genovese G, Rose SA, Handsaker RE, Schizophrenia Working Group of the Psychiatric Genomics Consortium, Daly MJ, Carroll MC, Stevens B, McCarroll SA.

The results implicate excessive complement activity in the development of schizophrenia and may help explain the reduced numbers of synapses in the brains of individuals with schizophrenia.

Nature. 2016 Feb 11;530(7589):177-83. DOI: 10.1038/nature16549