1. Cell Biology
  2. Immunology and Inflammation

A B cell actomyosin arc network couples integrin co-stimulation to mechanical force-dependent immune synapse formation

  1. Jia C Wang
  2. Yang-In Yim
  3. Xufeng Wu
  4. Valentin Jaumouille
  5. Andrew Cameron
  6. Clare M Waterman
  7. John H Kehrl
  8. John A Hammer III  Is a corresponding author
  1. National Heart, Lung and Blood Institute, National Institutes of Health, United States
  2. National Institutes of Allergy and Infectious Diseases, United States
https://doi.org/10.7554/eLife.72805
Share this article
Cite this article
  1. Jia C Wang
  2. Yang-In Yim
  3. Xufeng Wu
  4. Valentin Jaumouille
  5. Andrew Cameron
  6. Clare M Waterman
  7. John H Kehrl
  8. John A Hammer III
(2022)
A B cell actomyosin arc network couples integrin co-stimulation to mechanical force-dependent immune synapse formation
eLife 11:e72805.
https://doi.org/10.7554/eLife.72805
  2. Download BibTeX
  3. Download .RIS

Abstract

B-cell activation and immune synapse (IS) formation with membrane-bound antigens are actin-dependent processes that scale positively with the strength of antigen-induced signals. Importantly, ligating the B-cell integrin, LFA-1, with ICAM-1 promotes IS formation when antigen is limiting. Whether the actin cytoskeleton plays a specific role in integrin-dependent IS formation is unknown. Here we show using super-resolution imaging of mouse primary B cells that LFA-1: ICAM-1 interactions promote the formation of an actomyosin network that dominates the B-cell IS. This network is created by the formin mDia1, organized into concentric, contractile arcs by myosin 2A, and flows inward at the same rate as B-cell receptor (BCR): antigen clusters. Consistently, individual BCR microclusters are swept inward by individual actomyosin arcs. Under conditions where integrin is required for synapse formation, inhibiting myosin impairs synapse formation, as evidenced by reduced antigen centralization, diminished BCR signaling, and defective signaling protein distribution at the synapse. Together, these results argue that a contractile actomyosin arc network plays a key role in the mechanism by which LFA-1 co-stimulation promotes B-cell activation and IS formation.

Data availability

All data generated or analyzed during this study are included in the manuscript and supplementary information. Additionally, Source Data files have been provided for Figure 2 - figure supplement 1B

Article and author information

Author details

  1. Jia C Wang

    Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8666-4662

  2. Yang-In Yim

    Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.

  3. Xufeng Wu

    Light Microscopy Core, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.

  4. Valentin Jaumouille

    Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.

  5. Andrew Cameron

    Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.

  6. Clare M Waterman

    Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.

  7. John H Kehrl

    B Cell Molecular Immunology Section, National Institutes of Allergy and Infectious Diseases, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6526-159X

  8. John A Hammer III

    Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, United States
    For correspondence
    hammerj@nhlbi.nih.gov
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2496-5179

Funding

National Heart, Lung, and Blood Institute (1ZIAHL006121-04)

  • John A Hammer III

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations and protocols approved by the National Human Genome Research Institute Animal Use and Care Committee at the National Institutes of Health. All animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#H-0337) of the National Institutes of Health.

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

Metrics

  • 3,245
    views
  • 537
    downloads
  • 21
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Jia C Wang
  2. Yang-In Yim
  3. Xufeng Wu
  4. Valentin Jaumouille
  5. Andrew Cameron
  6. Clare M Waterman
  7. John H Kehrl
  8. John A Hammer III
(2022)
A B cell actomyosin arc network couples integrin co-stimulation to mechanical force-dependent immune synapse formation
eLife 11:e72805.
https://doi.org/10.7554/eLife.72805

Share this article

https://doi.org/10.7554/eLife.72805

Categories and tags

Research organism

Further reading

    1. Cell Biology
    2. Medicine

    Disruption of the novel nested gene Aff3ir mediates disturbed flow-induced atherosclerosis in mice

    Shuo He, Lei Huang ... Jinlong He
    Research Article

    Disturbed shear stress-induced endothelial atherogenic responses are pivotal in the initiation and progression of atherosclerosis, contributing to the uneven distribution of atherosclerotic lesions. This study investigates the role of Aff3ir-ORF2, a novel nested gene variant, in disturbed flow-induced endothelial cell activation and atherosclerosis. We demonstrate that disturbed shear stress significantly reduces Aff3ir-ORF2 expression in athero-prone regions. Using three distinct mouse models with manipulated Aff3ir-ORF2 expression, we demonstrate that Aff3ir-ORF2 exerts potent anti-inflammatory and anti-atherosclerotic effects in Apoe-/- mice. RNA sequencing revealed that interferon regulatory factor 5 (Irf5), a key regulator of inflammatory processes, mediates inflammatory responses associated with Aff3ir-ORF2 deficiency. Aff3ir-ORF2 interacts with Irf5, promoting its retention in the cytoplasm, thereby inhibiting the Irf5-dependent inflammatory pathways. Notably, Irf5 knockdown in Aff3ir-ORF2 deficient mice almost completely rescues the aggravated atherosclerotic phenotype. Moreover, endothelial-specific Aff3ir-ORF2 supplementation using the CRISPR/Cas9 system significantly ameliorated endothelial activation and atherosclerosis. These findings elucidate a novel role for Aff3ir-ORF2 in mitigating endothelial inflammation and atherosclerosis by acting as an inhibitor of Irf5, highlighting its potential as a valuable therapeutic approach for treating atherosclerosis.

    1. Cell Biology
    2. Developmental Biology

    Cell Signaling: Not all dimers are equal

    Jeet H Patel, Mary C Mullins
    Insight

    Disease-causing mutations in the signaling protein BMP4 impair its secretion, but only when it is made as a homodimer.

    1. Cell Biology
    2. Genetics and Genomics

    DNA replication in primary hepatocytes without the six-subunit ORC

    Róża K Przanowska, Yuechuan Chen ... Anindya Dutta
    Research Article

    The six-subunit ORC is essential for the initiation of DNA replication in eukaryotes. Cancer cell lines in culture can survive and replicate DNA replication after genetic inactivation of individual ORC subunits, ORC1, ORC2, or ORC5. In primary cells, ORC1 was dispensable in the mouse liver for endo-reduplication, but this could be explained by the ORC1 homolog, CDC6, substituting for ORC1 to restore functional ORC. Here, we have created mice with a conditional deletion of ORC2, which does not have a homolog. Although mouse embryo fibroblasts require ORC2 for proliferation, mouse hepatocytes synthesize DNA in cell culture and endo-reduplicate in vivo without ORC2. Mouse livers endo-reduplicate after simultaneous deletion of ORC1 and ORC2 both during normal development and after partial hepatectomy. Since endo-reduplication initiates DNA synthesis like normal S phase replication these results unequivocally indicate that primary cells, like cancer cell lines, can load MCM2-7 and initiate replication without ORC.