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An Efficient and High Yield Method for Isolation of Mouse Dendritic Cell Subsets
Published on: April 18, 2016
Expression and function of mixed lineage kinases in dendritic cells
Matthew E Handley1, Jane Rasaiyaah, James Barnett
1Department of Immunology and Molecular Pathology, University College London, Windeyer Institute, 46 Cleveland Street, London W1T 4JF, UK.
International Immunology
|August 19, 2007
Summary
Mixed lineage kinases (MLKs) are crucial for dendritic cell (DC) activation. MLK inhibition blocks T cell immunity induction via specific pattern recognition receptor (PRR) ligands, highlighting their selective role in DC responses.
Area of Science:
- Immunology
- Cell Biology
- Signal Transduction
Background:
- Dendritic cells (DCs) are key immune sentinels that initiate adaptive T cell immunity.
- Pattern recognition receptors (PRRs) on DCs recognize microbial structures, triggering DC activation and migration.
- Mitogen-activated protein kinases (MAPKs) mediate DC activation, but upstream pathways remain unclear.
Purpose of the Study:
- To investigate the role of mixed lineage kinases (MLKs) in dendritic cell activation.
- To determine if MLKs act as intermediaries between PRR ligation and MAPK activation in DCs.
Main Methods:
- Utilized a well-established dendritic cell model.
- Analyzed MLK mRNA and protein expression in DCs.
- Stimulated DCs with various PRR ligands (LPS, poly(I:C), zymosan).
- Assessed MLK phosphorylation and downstream MAPK activation (p38, JNK) upon MLK inhibition with CEP11004.
- Measured DC activation markers (cell-surface expression) and cytokine secretion.
Main Results:
- MLK2, MLK3, MLK4, and DLK mRNA and MLK2, MLK3, and DLK protein were detected in DCs.
- LPS and poly(I:C) stimulation induced MLK3 phosphorylation, unlike zymosan.
- MLK inhibition with CEP11004 blocked p38 and JNK activation in response to LPS and poly(I:C), but not zymosan.
- MLK inhibition impaired DC activation, evidenced by reduced cell-surface marker expression and cytokine secretion.
Conclusions:
- MLKs are expressed in dendritic cells and play a significant role in their activation.
- The involvement of MLKs in DC activation is stimulus-dependent, suggesting a selective signaling pathway.
- MLKs represent a potential therapeutic target for modulating adaptive immune responses initiated by DCs.
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