Stimulation strength controls the rate of initiation but not the molecular organization of TCR-induced signalling
Abstract
Millions of naïve T cells with different TCRs may interact with a peptide-MHC ligand, but very few will activate. Remarkably, this fine control is orchestrated using a limited set of intracellular machinery. It remains unclear whether changes in stimulation strength alter the programme of signalling events leading to T cell activation. Using mass cytometry to simultaneously measure multiple signalling pathways during activation of murine CD8+ T cells, we found a programme of distal signalling events that is shared, regardless of the strength of TCR stimulation. Moreover, the relationship between transcription of early response genes Nr4a1 and Irf8 and activation of the ribosomal protein S6 is also conserved across stimuli. Instead, we found that stimulation strength dictates the rate with which cells initiate signalling through this network. These data suggest that TCR-induced signalling results in a coordinated activation program, modulated in rate but not organization by stimulation strength.
Data availability
Raw mass cytometry data can be found on the Flow Repository, accession numbers FR-FCM-Z2CX and FR-FCM-Z2CP.Full results of mass cytometry analyses are included as Supplementary File 5.Source data for summary plots of flow cytometry-measured signaling markers in T cells stimulated with peptide-loaded BMDCs (Figure 7a) are included as Figure 7 - Source Data File 1.Analysis code is available athttps://github.com/MarioniLab/SignallingMassCytoStimStrength
Article and author information
Author details
Funding
Wellcome (103930,100140,217100)
- Gillian M Griffiths
Wellcome (204017/Z/16/Z)
- Claire Y Ma
Cancer Research UK (A17197)
- John C Marioni
Medical Research Council (MR/P014178/1)
- Arianne C Richard
Addenbrooke's Charitable Trust, Cambridge University Hospitals (23/17 A (ii))
- Claire Y Ma
European Molecular Biology Organization
- John C Marioni
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animal experimentation: Experiments were carried out under Project Licence PPL 70/8590. This research has been regulated under the Animals (Scientific Procedures) Act 1986 Amendment Regulations 2012 following ethical review by the University of Cambridge Animal Welfare and Ethical Review Body (AWERB).
Copyright
© 2020, Ma 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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