T cell stiffness is enhanced upon formation of immunological synapse
T cells are activated by target cells via an intimate contact, termed immunological synapse (IS). Cellular mechanical properties, especially stiffness, are essential to regulate cell functions. However, T cell stiffness at a subcellular level at the IS still remains largely elusive. In this work, we established an atomic force microscopy (AFM)-based elasticity mapping method on whole T cells to obtain an overview of the stiffness with a resolution of ~ 60 nm. Using primary human CD4+ T cells, we show that when T cells form IS with stimulating antibody-coated surfaces, the lamellipodia are stiffer than the cell body. Upon IS formation, T cell stiffness is enhanced both at the lamellipodia and on the cell body. Chelation of intracellular Ca2+ abolishes IS-induced stiffening at the lamellipodia but has no influence on cell body-stiffening, suggesting different regulatory mechanisms of IS-induced stiffening at the lamellipodia and the cell body.
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Article and author information
Deutsche Forschungsgemeinschaft (SFB1027 A2)
- Bin Qu
Deutsche Forschungsgemeinschaft (SFB1027 B2)
- Markus Bischoff
Deutsche Forschungsgemeinschaft (SPP1782 ID79/2-2)
- Sandra Iden
Leibniz-Gemeinschaft (INM Fellowship)
- Bin Qu
Deutsche Forschungsgemeinschaft (SFB1027 A12)
- Sandra Iden
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Alphee Michelot, Institut de Biologie du Développement, France
- Preprint posted: January 8, 2021 (view preprint)
- Received: January 18, 2021
- Accepted: July 26, 2021
- Accepted Manuscript published: July 27, 2021 (version 1)
- Version of Record published: August 12, 2021 (version 2)
© 2021, Jung 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.
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