| Literature DB >> 15353589 |
Kei Ohnuma1, Tadanori Yamochi, Masahiko Uchiyama, Kunika Nishibashi, Noritada Yoshikawa, Noriaki Shimizu, Satoshi Iwata, Hirotoshi Tanaka, Nam H Dang, Chikao Morimoto.
Abstract
CD26 is a T cell costimulatory molecule with dipeptidyl peptidase IV activity in its extracellular region. We previously reported that recombinant soluble CD26 enhanced T cell proliferation induced by the recall antigen tetanus toxoid (TT). However, the mechanism involved in this enhancement is not yet elucidated. We now demonstrate that CD26 binds Caveolin-1 on antigen-presenting cells, and that residues 201-211 of CD26 along with the serine catalytic site at residue 630 contribute to binding to caveolin-1 scaffolding domain. In addition, after CD26-caveolin-1 interaction on TT-loaded monocytes, caveolin-1 is phosphorylated, which links to activate NF-kappaB, followed by up-regulation of CD86. Finally, reduced caveolin-1 expression on monocytes inhibits CD26-mediated CD86 up-regulation and abrogates CD26 effect on TT-induced T cell proliferation. Taken together, these results strongly suggest that CD26-caveolin-1 interaction plays a role in the up-regulation of CD86 on TT-loaded monocytes and subsequent engagement with CD28 on T cells, leading to antigen-specific T cell activation.Entities:
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Year: 2004 PMID： 15353589 PMCID： PMC521134 DOI： 10.1073/pnas.0405266101
Source DB: PubMed Journal: Proc Natl Acad Sci U S A ISSN： 0027-8424 Impact factor: 11.205