The many ways tissue phagocytes respond to dying cells
1Jill Roberts Institute for Research in Inflammatory Bowel Disease, Joan and Sanford I. Weill Department of Medicine, Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, NY, USA.
Immunological Reviews
|May 3, 2017
Summary
Professional phagocytes efficiently clear apoptotic cells, with macrophages processing cellular debris and dendritic cells promoting immune suppression. This specialized cell removal is vital for tissue homeostasis and preventing inflammatory diseases.
Area of Science:
- Immunology
- Cell Biology
- Physiology
Background:
- Apoptosis is crucial for tissue health, requiring efficient removal of dead cells to prevent inflammation.
- Professional phagocytes, such as macrophages and dendritic cells, are specialized for engulfing and processing apoptotic cells.
- Dysfunctional apoptotic cell clearance is linked to chronic inflammatory and autoimmune diseases.
Purpose of the Study:
- To elucidate the distinct roles of tissue-resident phagocytes in clearing apoptotic cells.
- To understand the mechanisms by which phagocytes mediate immune suppression following apoptotic cell uptake.
- To explore the connection between phagocyte functions and inflammatory/autoimmune diseases.
Main Methods:
- In situ tracking of apoptotic cells to observe phagocyte interactions.
- Analysis of phagocyte-specific mechanisms involved in immune suppression.
- Investigating the molecular pathways modulated in phagocytes after apoptotic cell phagocytosis.
Main Results:
- Macrophages primarily process apoptotic cell-derived lipids and nucleotides, clearing the bulk of cellular debris.
- Dendritic cells transport apoptotic cells to lymph nodes, inducing regulatory T cells and suppressing inflammation.
- Phagocyte engagement with apoptotic cells activates distinct, specialized immune-suppressive pathways.
Conclusions:
- Phagocyte specialization in apoptotic cell clearance is essential for maintaining tissue homeostasis.
- Distinct roles of macrophages and dendritic cells in apoptotic cell removal contribute to immune regulation.
- Understanding these processes offers insights into potential therapeutic strategies for inflammatory and autoimmune conditions.
Keywords:
apoptosis/autophagyautoimmunitydendritic cellsmonocytes/macrophagesphagocytosistoll-like receptors/pattern recognition receptorsMore Related Videos
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