Zur Kurzanzeige

dc.date.accessioned2024-09-11T11:24:18Z
dc.date.available2024-09-11T11:24:18Z
dc.date.issued2015-04-29
dc.identifierdoi:10.17170/kobra-2024082910751
dc.identifier.urihttp://hdl.handle.net/123456789/16036
dc.description.sponsorshipPart of the numerical work was supported by the Helmholtz Aliance on Systems Biology (SB Cancer, Submodule V.7) and the ViroQuant consortium.eng
dc.language.isoeng
dc.rightsNamensnennung 4.0 International*
dc.rights.urihttp://creativecommons.org/licenses/by/4.0/*
dc.subjectcytokineseng
dc.subjectparacrine signalingeng
dc.subjectsynapseseng
dc.subjectsecretioneng
dc.subjectcytokine receptorseng
dc.subjectT cellseng
dc.subjectimmune receptor signalingeng
dc.subjectautocrine signalingeng
dc.subject.ddc510
dc.subject.ddc570
dc.titleThree-Dimensional Gradients of Cytokine Signaling between T Cellseng
dc.typeAufsatz
dcterms.abstractImmune responses are regulated by diffusible mediators, the cytokines, which act at sub-nanomolar concentrations. The spatial range of cytokine communication is a crucial, yet poorly understood, functional property. Both containment of cytokine action in narrow junctions between immune cells (immunological synapses) and global signaling throughout entire lymph nodes have been proposed, but the conditions under which they might occur are not clear. Here we analyze spatially three-dimensional reaction-diffusion models for the dynamics of cytokine signaling at two successive scales: in immunological synapses and in dense multicellular environments. For realistic parameter values, we observe local spatial gradients, with the cytokine concentration around secreting cells decaying sharply across only a few cell diameters. Focusing on the well-characterized T-cell cytokine interleukin-2, we show how cytokine secretion and competitive uptake determine this signaling range. Uptake is shaped locally by the geometry of the immunological synapse. However, even for narrow synapses, which favor intrasynaptic cytokine consumption, escape fluxes into the extrasynaptic space are expected to be substantial (≥20% of secretion). Hence paracrine signaling will generally extend beyond the synapse but can be limited to cellular microenvironments through uptake by target cells or strong competitors, such as regulatory T cells. By contrast, long-range cytokine signaling requires a high density of cytokine producers or weak consumption (e.g., by sparsely distributed target cells). Thus in a physiological setting, cytokine gradients between cells, and not bulk-phase concentrations, are crucial for cell-to-cell communication, emphasizing the need for spatially resolved data on cytokine signaling. Author Summary The adaptive immune system fights pathogens through the activation of immune cell clones that specifically recognize a particular pathogen. Tight contacts, so-called immunological synapses, of immune cells with cells that present ‘digested’ pathogen molecules are pivotal for ensuring specificity. The discovery that immune responses are regulated by small diffusible proteins – the cytokines – has been surprising because cytokine diffusion to ‘bystander’ cells might compromise specificity. It has therefore been argued that cytokines are trapped in immunological synapses, whereas other authors have found that cytokines act on a larger scale through entire lymph nodes. Measurements of cytokine concentrations with fine spatial resolution have not been achieved. Here, we study the spatio-temporal dynamics of cytokines through mathematical analysis and three-dimensional numerical simulation and identify key parameters that control signaling range. We predict that even tight immunological synapses leak a substantial portion of the secreted cytokines. Nevertheless, rapid cellular uptake will render cytokine signals short-range and thus incidental activation of bystander cells can be limited. Long-range signals will only occur with multiple secreting cells or/and slow consumption by sparse target cells. Thus our study identifies key determinants of the spatial range of cytokine communication in realistic multicellular geometries.eng
dcterms.accessRightsopen access
dcterms.creatorThurley, Kevin
dcterms.creatorGerecht, Daniel
dcterms.creatorFriedmann, Elfriede
dcterms.creatorHöfer, Thomas
dc.relation.doidoi:10.1371/journal.pcbi.1004206
dc.subject.swdCytokineger
dc.subject.swdPlesiokrinieger
dc.subject.swdSynapseger
dc.subject.swdSekretionger
dc.subject.swdRezeptorger
dc.subject.swdT-Lymphozytger
dc.type.versionpublishedVersion
dcterms.source.identifiereissn:1553-7358
dcterms.source.issue4
dcterms.source.journalPLOS Computational Biologyeng
dcterms.source.volumeVolume 11
kup.iskupfalse
dcterms.source.articlenumbere1004206


Dateien zu dieser Ressource

Thumbnail
Thumbnail

Das Dokument erscheint in:

Zur Kurzanzeige

Namensnennung 4.0 International
Solange nicht anders angezeigt, wird die Lizenz wie folgt beschrieben: Namensnennung 4.0 International