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The Actin-Capping Protein Alpha-Adducin Is Required for T-Cell Costimulation.

ABSTRACT: Alpha-adducin (Add1) is a critical component of the actin-spectrin network in erythrocytes, acting to cap the fast-growing, barbed ends of actin filaments, and recruiting spectrin to these junctions. Add1 is highly expressed in T cells, but its role in T-cell activation has not been examined. Using a conditional knockout model, we show that Add1 is necessary for complete activation of CD4+ T cells in response to low levels of antigen but is dispensable for CD8+ T cell activation and response to infection. Surprisingly, costimulatory signals through CD28 were completely abrogated in the absence of Add1. This study is the first to examine the role of actin-capping in T cells, and it reveals a previously unappreciated role for the actin cytoskeleton in regulating costimulation.

SUBMITTER: Thauland TJ

PROVIDER: S-EPMC6879651 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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The Actin-Capping Protein Alpha-Adducin Is Required for T-Cell Costimulation.

Thauland Timothy J TJ Khan Humza A HA Butte Manish J MJ

Frontiers in immunology 20191120

Alpha-adducin (Add1) is a critical component of the actin-spectrin network in erythrocytes, acting to cap the fast-growing, barbed ends of actin filaments, and recruiting spectrin to these junctions. Add1 is highly expressed in T cells, but its role in T-cell activation has not been examined. Using a conditional knockout model, we show that Add1 is necessary for complete activation of CD4+ T cells in response to low levels of antigen but is dispensable for CD8+ T cell activation and response to ...[more]

PMID: 31824498

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