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T cell responses modulated through interaction between CD8alphaalpha and the nonclassical MHC class I molecule, TL.

A J Leishman·O V Naidenko·A Attinger·F Koning·C J Lena·Y Xiong·H C Chang·E Reinherz·M Kronenberg·H Cheroutre
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Abstract

The thymus leukemia antigen (TL) is a nonclassical class I molecule, expressed abundantly on intestinal epithelial cells. We show that, in contrast to other major histocompatibility complex (MHC) class I molecules that bind CD8alphabeta, TL preferentially binds the homotypic form of CD8alpha (CD8alphaalpha). Thus, TL tetramers react specifically to CD8alphaalpha-expressing cells, including most intestinal intraepithelial lymphocytes. Compared with CD8alphabeta, which recognizes the same MHC as the T cell receptor (TCR) and thus acts as a TCR coreceptor, high-affinity binding of CD8alphaalpha to TL modifies responses mediated by TCR recognition of antigen presented by distinct MHC molecules. These findings define a novel mechanism of lymphocyte regulation through CD8alphaalpha and MHC class I.

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Amino Acid MotifsAnimalsAntigen PresentationCD8 AntigensCD8-Positive T-LymphocytesEnterocytesEnzyme-Linked Immunosorbent AssayFlow CytometryGene DeletionH-2 AntigensMaleMembrane GlycoproteinsMiceMice, Inbred C57BLMice, TransgenicProtein Interaction MappingProtein Structure, TertiaryReceptors, Antigen, T-CellSubstrate SpecificitySurface Plasmon ResonanceTumor Cells, CulturedJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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A J Leishman, O V Naidenko, A Attinger, F Koning, C J Lena, Y Xiong, H C Chang, E Reinherz, M Kronenberg, H Cheroutre. 2001-11-30. T cell responses modulated through interaction between CD8alphaalpha and the nonclassical MHC class I molecule, TL.. https://doi.org/10.1126/science.1063564

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