Soluble peptide–MHC monomers cause activation of CD8+ T cells through transfer of the peptide to T cell MHC molecules
Q Ge, JD Stone, MT Thompson… - Proceedings of the …, 2002 - National Acad Sciences
Proceedings of the National Academy of Sciences, 2002•National Acad Sciences
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 Ld and Kb 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 naïve and effector CD8+ T cells …
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 Ld and Kb 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 naïve and effector CD8+ T cells …
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 Ld and Kb 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 naïve and effector CD8+ T cells, but through an unexpected mechanism that involves transfer of peptide from soluble monomers to T cell endogenous MHC (Kb) molecules. The result is that T cells, acting as antigen-presenting cells, are able to activate other naïve T cells.
National Acad Sciences
