Pattern recognition receptors in the immune response against dying cells
Pascale Jeannin1, Sébastien Jaillon, Yves Delneste
1Institut National de la Santé et de la Recherche Médicale, U564, University Hospital of Angers, France. pascale.jeannin@univ-angers.fr
Current Opinion in Immunology
|June 17, 2008
Summary
Pattern recognition receptors (PRR) sense dying cells, influencing immune responses. Recognizing apoptotic cells prevents autoimmunity, while necrotic cells activate immunity via PRR.
Area of Science:
- Immunology
- Cell Biology
Background:
- Pattern recognition receptors (PRR) are crucial immune sensors distinguishing self from non-self, bridging innate and adaptive immunity.
- PRR mediate microbe recognition, phagocytosis, and cellular activation, playing a role in recognizing dying cells.
- The immune system's response to dying cells is critical for preventing autoimmune reactions.
Purpose of the Study:
- To review the role of pattern recognition receptors (PRR) in recognizing dying cells.
- To elucidate the mechanisms by which PRR distinguish between apoptotic and necrotic cells.
- To summarize the consequences of PRR-mediated recognition of dying cells on immune responses.
Main Methods:
- Literature review of studies on pattern recognition receptors and cell death.
- Analysis of molecular mechanisms involved in apoptotic and necrotic cell recognition.
- Synthesis of data on immune outcomes following exposure to dying cell antigens.
Main Results:
- PRR recognize dying cells through various mechanisms, including soluble PRR, endocytic receptors, and signaling PRR.
- Apoptotic cell recognition by PRR, involving molecules like pentraxins and scavenger receptors, typically induces immunosuppression.
- Necrotic cells, releasing molecules such as heat shock proteins (HSP) and high-mobility group box 1 protein (HMGB1), activate immune cells via PRR.
Conclusions:
- PRR play a pivotal role in determining the immune response to dying cells.
- The differential recognition of apoptotic versus necrotic cells by PRR dictates whether an immunosuppressive or immunostimulatory outcome occurs.
- Understanding PRR involvement in dying cell recognition is key to modulating immune responses and preventing autoimmunity.
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