CCR7 and its ligands: balancing immunity and tolerance
Reinhold Förster1, Ana Clara Davalos-Misslitz, Antal Rot
1Institute of Immunology, Hannover Medical School; 30625 Hannover, Germany. foerster.reinhold@mh-hannover.de
Nature Reviews. Immunology
|April 2, 2008
Summary
The CC-chemokine receptor 7 (CCR7) guides immune cells to lymphoid organs, playing a crucial role in balancing protective immunity against pathogens and maintaining self-tolerance. Understanding CCR7
Area of Science:
- Immunology
- Cellular and Molecular Biology
- Lymphocyte Trafficking
Background:
- The immune system must distinguish between harmful pathogens and harmless self/environmental antigens to maintain health.
- CC-chemokine receptor 7 (CCR7) is increasingly recognized for its role in immune cell navigation within lymphoid organs.
- CCR7's ligands, CCL19 and CCL21, are key mediators of immune cell homing and organization.
Purpose of the Study:
- To elucidate the cellular and molecular mechanisms by which CCR7 and its ligands (CCL19, CCL21) regulate immune responses.
- To investigate CCR7's function in maintaining the balance between immunity and self-tolerance.
- To understand CCR7's role in immune cell trafficking to and within lymphoid tissues.
Main Methods:
- Review of existing literature on CCR7, CCL19, and CCL21.
- Analysis of cellular and molecular pathways involved in immune cell migration.
- Focus on CCR7's role in thymic architecture, T cell homing, and dendritic cell migration.
Main Results:
- CCR7 is essential for organizing thymic architecture and function.
- CCR7 mediates lymph-node homing of naive and regulatory T cells via high endothelial venules.
- CCR7 facilitates the migration of dendritic cells to lymph nodes during both steady state and inflammation.
Conclusions:
- CCR7 and its ligands are critical regulators of immune cell trafficking, essential for orchestrating adaptive immunity.
- CCR7 plays a pivotal role in maintaining immune homeostasis by balancing protective immunity and self-tolerance.
- Further research into CCR7-mediated pathways can inform strategies for immune modulation.
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