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CD8?? and -?? isotypes are equally recruited to the immunological synapse through their ability to bind to MHC class I.

ABSTRACT: Bimolecular fluorescence complementation was used to engineer CD8 molecules so that CD8?? and CD8?? dimers can be independently visualized on the surface of a T cell during antigen recognition. Using this approach, we show that CD8?? is recruited to the immunological synapse almost as well as CD8??, but because the kinase Lck associates preferentially with CD8?? in lipid rafts, CD8?? is the weaker co-receptor. During recognition of the strong CD8?? ligand H2-TL, CD8?? is preferentially recruited. Thus, recruitment of the two CD8 species correlates with their relative binding to the available ligands, rather than with the co-receptor functions of the CD8 species.

SUBMITTER: Rybakin V

PROVIDER: S-EPMC3245696 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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CD8αα and -αβ isotypes are equally recruited to the immunological synapse through their ability to bind to MHC class I.

Rybakin Vasily V Clamme Jean-Pierre JP Ampudia Jeanette J Yachi Pia P PP Gascoigne Nicholas R J NR

EMBO reports 20111201 12

Bimolecular fluorescence complementation was used to engineer CD8 molecules so that CD8αα and CD8αβ dimers can be independently visualized on the surface of a T cell during antigen recognition. Using this approach, we show that CD8αα is recruited to the immunological synapse almost as well as CD8αβ, but because the kinase Lck associates preferentially with CD8αβ in lipid rafts, CD8αα is the weaker co-receptor. During recognition of the strong CD8αα ligand H2-TL, CD8αα is preferentially recruited ...[more]

PMID: 22081144

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