Na+ influx via Orai1 inhibits intracellular ATP induced mTORC2 signaling to disrupt CD4 T cell gene expression and differentiation

  1. Yong Miao
  2. Jaya Bhushan
  3. Adish Dani
  4. Monika Vig  Is a corresponding author
  1. Washington University School of Medicine, United States

Abstract

T cell effector functions require sustained calcium influx. However, the signaling and phenotypic consequences of non-specific sodium permeation via calcium channels remain unknown. α-SNAP is a crucial component of Orai1 channels, and its depletion disrupts the functional assembly of Orai1 multimers. Here we show that α-SNAP hypomorph, hydrocephalos with hopping gait, Napahyh/hyh mice harbor significant defects in CD4 T cell gene expression and Foxp3 regulatory T cell (Treg) differentiation. Mechanistically, TCR stimulation induced rapid sodium influx in Napahyh/hyh CD4 T cells, which reduced intracellular ATP, [ATP]i. Depletion of [ATP]i inhibited mTORC2 dependent NFκB activation in Napahyh/hyh cells but ablation of Orai1 restored it. Remarkably, TCR stimulation in the presence of monensin phenocopied the defects in Napahyh/hyh signaling and Treg differentiation, but not IL-2 expression. Thus, non-specific sodium influx via bonafide calcium channels disrupts unexpected signaling nodes and may provide mechanistic insights into some divergent phenotypes associated with Orai1 function.

Data availability

The following data sets were generated

Article and author information

Author details

  1. Yong Miao

    Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Jaya Bhushan

    Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Adish Dani

    Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5491-7709
  4. Monika Vig

    Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, United States
    For correspondence
    mvig@WUSTL.EDU
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4770-8853

Funding

American Cancer Society (ACS-RSG 14-040-01-CSM)

  • Monika Vig

National Institutes of Health (AI108636)

  • Monika Vig

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

Ethics

Animal experimentation: All animal experiments were performed according to the guidelines of the Animal Studies Committee of the Washington University School of Medicine in Saint Louis, Protocol Approval Number 20150289.

Copyright

© 2017, Miao et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

Metrics

  • 1,848
    views
  • 332
    downloads
  • 9
    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. Yong Miao
  2. Jaya Bhushan
  3. Adish Dani
  4. Monika Vig
(2017)
Na+ influx via Orai1 inhibits intracellular ATP induced mTORC2 signaling to disrupt CD4 T cell gene expression and differentiation
eLife 6:e25155.
https://doi.org/10.7554/eLife.25155

Share this article

https://doi.org/10.7554/eLife.25155

Further reading

    1. Immunology and Inflammation
    Yan Qian, Qiannv Liu ... Pengyan Xia
    Research Article

    The T6SS of Pseudomonas aeruginosa plays an essential role in the establishment of chronic infections. Inflammasome-mediated inflammatory cytokines are crucial for host defense against bacterial infections. We found that P. aeruginosa infection activates the non-canonical inflammasome in macrophages, yet it inhibits the downstream activation of the NLRP3 inflammasome. The VgrG2b of P. aeruginosa is recognized and cleaved by caspase-11, generating a free C-terminal fragment. The VgrG2b C-terminus can bind to NLRP3, inhibiting the activation of the NLRP3 inflammasome by rejecting NEK7 binding to NLRP3. Administration of a specific peptide that inhibits caspase-11 cleavage of VgrG2b significantly improves mouse survival during infection. Our discovery elucidates a mechanism by which P. aeruginosa inhibits host immune response, providing a new approach for the future clinical treatment of P. aeruginosa infections.

    1. Immunology and Inflammation
    2. Medicine
    Ole Bæk, Tik Muk ... Duc Ninh Nguyen
    Research Article

    Preterm infants are susceptible to neonatal sepsis, a syndrome of pro-inflammatory activity, organ damage, and altered metabolism following infection. Given the unique metabolic challenges and poor glucose regulatory capacity of preterm infants, their glucose intake during infection may have a high impact on the degree of metabolism dysregulation and organ damage. Using a preterm pig model of neonatal sepsis, we previously showed that a drastic restriction in glucose supply during infection protects against sepsis via suppression of glycolysis-induced inflammation, but results in severe hypoglycemia. Now we explored clinically relevant options for reducing glucose intake to decrease sepsis risk, without causing hypoglycemia and further explore the involvement of the liver in these protective effects. We found that a reduced glucose regime during infection increased survival via reduced pro-inflammatory response, while maintaining normoglycemia. Mechanistically, this intervention enhanced hepatic oxidative phosphorylation and possibly gluconeogenesis, and dampened both circulating and hepatic inflammation. However, switching from a high to a reduced glucose supply after the debut of clinical symptoms did not prevent sepsis, suggesting metabolic conditions at the start of infection are key in driving the outcome. Finally, an early therapy with purified human inter-alpha inhibitor protein, a liver-derived anti-inflammatory protein, partially reversed the effects of low parenteral glucose provision, likely by inhibiting neutrophil functions that mediate pathogen clearance. Our findings suggest a clinically relevant regime of reduced glucose supply for infected preterm infants could prevent or delay the development of sepsis in vulnerable neonates.