1. Migrating lymph dendritic cells contain intracellular CD40 that is mobilized to the immunological synapse during interactions with antigen-specific T lymphocytes.
- Author
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Foster N, Turnbull EL, and Macpherson G
- Subjects
- Animals, CD40 Antigens immunology, Cell Membrane metabolism, Cell Polarity immunology, Cells, Cultured, Dendritic Cells cytology, Dendritic Cells metabolism, Intracellular Fluid immunology, Intracellular Fluid metabolism, Lymph cytology, Lymph metabolism, Lymphocyte Activation immunology, Protein Isoforms metabolism, Rats, Signal Transduction immunology, T-Lymphocyte Subsets cytology, T-Lymphocyte Subsets metabolism, CD40 Antigens metabolism, Cell Communication immunology, Cell Movement immunology, Dendritic Cells immunology, Epitopes, T-Lymphocyte immunology, Immunological Synapses metabolism, Lymph immunology, T-Lymphocyte Subsets immunology
- Abstract
Steady state migrating rat lymph dendritic cells (LDC) are semimature, expressing high levels of surface MHC class II, but low levels of surface costimulatory molecules. In this study, we show that surface CD40 is not detectable, but LDC contain intracellular CD40. Multiple isoforms of CD40 were detected, including the type 1 isoform required for signal transduction. Culture of LDC with syngeneic T cells does not induce redistribution of cytoplasmic CD40. When LDC were cultured with naive allogeneic CD4(+) T lymphocytes, polarization of CD40 to the immune synapse occurred between 3 and 6 h postculture. By 24 h, although large numbers of T cells were engaged with LDC, CD40 could not be detected in LDC or at the synapses. We conclude that migrating LDC contain stores of CD40 that can be mobilized rapidly to the sites of interaction with Ag-specific T cells. The disappearance of CD40 by 24 h may help in the regulation of T cell activation.
- Published
- 2012
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