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09:43
Measurement of Heme Synthesis Levels in Mammalian Cells
Published on: July 9, 2015
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Red alert: labile heme is an alarmin
Miguel P Soares1, Marcelo T Bozza2
1Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal.
Current Opinion in Immunology
|January 8, 2016
Summary
Labile heme, released from damaged cells, signals danger to the immune system. This finding identifies heme as an alarmin, crucial for understanding hemolysis and rhabdomyolysis.
Area of Science:
- Biochemistry
- Immunology
- Cellular Biology
Background:
- Alarmins are endogenous molecules signaling cellular damage.
- Heme is a prosthetic group in hemoproteins like hemoglobin and myoglobin.
- Damaged cells release heme, forming labile heme.
Purpose of the Study:
- To investigate the role of labile heme in cellular damage signaling.
- To determine if labile heme functions as an alarmin.
- To understand the implications for hemolysis and rhabdomyolysis.
Main Methods:
- Analysis of heme release from damaged red blood cells and muscle cells.
- Investigation of heme interaction with pattern recognition receptors (PRR).
- Assessment of immune responses mediated by labile heme.
Main Results:
- Oxidized hemoglobin and myoglobin release heme upon cell damage.
- Labile heme is sensed by PRRs on innate immune cells and T regulatory cells (TREG).
- This sensing triggers an adaptive response to cell damage.
Conclusions:
- Labile heme acts as a damage-associated molecular pattern (DAMP).
- Heme functions as an alarmin, alerting to red blood cell or muscle damage.
- This alarmin role is critical in regulating the pathology of hemolysis and rhabdomyolysis.
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