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Updated: Aug 11, 2026

Spatial and Temporal Control of T Cell Activation Using a Photoactivatable Agonist
Published on: April 25, 2018
Dynamic interactions of macrophages with T cells during antigen presentation
D M Underhill1, M Bassetti, A Rudensky
1Department of Immunology, University of Washington, Seattle, Washington 98195, USA.
Abstract:
We have established a method for real-time video analysis of the interaction of antigen-presenting cells (APCs) with T cells. Green fluorescent protein expression controlled by a nuclear factor of activated T cells (NFAT)-responsive promoter permits the visualization of productive antigen presentation in single T cells. The readout is rapid (within 2 h) and semiquantitative and allows analysis by video microscopy and flow cytometry. Using this approach, we demonstrate that macrophages have the capacity to simultaneously activate multiple T cells. In addition, the interaction of T cells with macrophages is extraordinarily dynamic: after initial stable contact, the T cells migrate continuously on the surface of the macrophage and from APC to APC during productive antigen presentation. Thus, T cells sum up signals from multiple interactions with macrophages during stimulation.
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