Related Experiment Video
Updated: Jun 6, 2026

Real-time Live Imaging of T-cell Signaling Complex Formation
Published on: June 23, 2013
Actin-bundling protein L-plastin regulates T cell activation
Chen Wang1, Sharon Celeste Morley, David Donermeyer
1Department of Microbial Pathogenesis, Genentech, Inc., South San Francisco, CA 94080, USA.
None:
Engagement of TCRs induces actin rearrangements, which are critical for T cell activation. T cell responses require new actin polymerization, but the significance of higher-order actin structures, such as microfilament bundles, is unknown. To determine the role of the actin-bundling protein leukocyte-plastin (L-plastin; LPL) in this process, T cells from LPL(-/-) mice were studied. LPL(-/-) T cells were markedly defective in TCR-mediated cytokine production and proliferation. LPL(-/-) T cells also spread inefficiently on surfaces with immobilized TCR ligands and formed smaller immunological synapses with APCs, likely due to defective formation of lamellipodia. LPL(-/-) mice showed delayed rejection of skin allografts after release from immunosuppression. Moreover, LPL(-/-) mice developed much less severe neurologic symptoms in experimental autoimmune encephalomyelitis, which correlated with impaired T cell responses to Ag, manifested by reduced proliferation and production of IFN-γ and IL-17. Thus, LPL-dependent actin bundling facilitates the formation of lamellipodia and normal immunological synapses and thereby enables T cell activation.
Related Concept Videos
Cytoskeletal Linker Proteins - Plakins
Cytoskeletal Accessory Proteins
Formation of Higher-order Actin Filaments
The high-order actin networks...
T Cell Activation and Clonal Selection
Naive T cells that have not yet encountered an antigen express two primary CD...
Actin Polymerization and Cell Motility
Actin cytoskeleton dynamics can produce pushing, pulling, and resistance forces that help the cell to migrate.
Catenins
Catenins in Cell Junctions
Catenins bind to cell adhesion molecules such as cadherins and link them to different cytoskeletal proteins depending on the type of cell junction. At the adherens...

