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Soluble peptide-MHC monomers cause activation of CD8+ T cells through transfer of the peptide to T cell MHC molecules.

ABSTRACT: T cell receptor (TCR)-mediated activation of CD4(+) T cells is known to require multivalent engagement of the TCR by, for example, oligomeric peptide-MHC complexes. In contrast, for CD8(+) T cells, there is evidence for TCR-mediated activation by univalent engagement of the TCR. We have here compared oligomeric and monomeric L(d) and K(b) peptide-MHC complexes and free peptide as stimulators of CD8(+) T cells expressing the 2C TCR. We found that the monomers are indeed effective in activating naive and effector CD8(+) T cells, but through an unexpected mechanism that involves transfer of peptide from soluble monomers to T cell endogenous MHC (K(b)) molecules. The result is that T cells, acting as antigen-presenting cells, are able to activate other naive T cells.

SUBMITTER: Ge Q

PROVIDER: S-EPMC129758 | biostudies-literature | 2002 Oct

REPOSITORIES: biostudies-literature

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Soluble peptide-MHC monomers cause activation of CD8+ T cells through transfer of the peptide to T cell MHC molecules.

Ge Qing Q Stone Jennifer D JD Thompson M Todd MT Cochran Jennifer R JR Rushe Mia M Eisen Herman N HN Chen Jianzhu J Stern Lawrence J LJ

Proceedings of the National Academy of Sciences of the United States of America 20021008 21

T cell receptor (TCR)-mediated activation of CD4(+) T cells is known to require multivalent engagement of the TCR by, for example, oligomeric peptide-MHC complexes. In contrast, for CD8(+) T cells, there is evidence for TCR-mediated activation by univalent engagement of the TCR. We have here compared oligomeric and monomeric L(d) and K(b) peptide-MHC complexes and free peptide as stimulators of CD8(+) T cells expressing the 2C TCR. We found that the monomers are indeed effective in activating na ...[more]

PMID: 12374859

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