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Cofilin peptide homologs interfere with immunological synapse formation and T cell activation.

ABSTRACT: The formation of supramolecular activation clusters within the immunological synapse, crucial for sustained signaling and T lymphocyte activation, requires costimulation-dependent reorganization of the actin cytoskeleton. Here we have identified the actin-remodeling protein cofilin as a key player in this process. Cell-permeable peptides that block costimulation-induced cofilin/F-actin interactions in untransformed human T lymphocytes impair receptor capping and immunological synapse formation at the interface between T cells and antigen-presenting cells. As a consequence, T cell activation, as measured by cytokine production and proliferation, is inhibited.

SUBMITTER: Eibert SM

PROVIDER: S-EPMC357034 | biostudies-literature | 2004 Feb

REPOSITORIES: biostudies-literature

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Cofilin peptide homologs interfere with immunological synapse formation and T cell activation.

Eibert Sybille M SM Lee Kyeong-Hee KH Pipkorn Rüdiger R Sester Urban U Wabnitz Guido H GH Giese Thomas T Meuer Stefan C SC Samstag Yvonne Y

Proceedings of the National Academy of Sciences of the United States of America 20040203 7

The formation of supramolecular activation clusters within the immunological synapse, crucial for sustained signaling and T lymphocyte activation, requires costimulation-dependent reorganization of the actin cytoskeleton. Here we have identified the actin-remodeling protein cofilin as a key player in this process. Cell-permeable peptides that block costimulation-induced cofilin/F-actin interactions in untransformed human T lymphocytes impair receptor capping and immunological synapse formation a ...[more]

PMID: 14762171

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