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Published on: August 26, 2016
CRIg: a macrophage complement receptor required for phagocytosis of circulating pathogens
Karim Y Helmy1, Kenneth J Katschke, Nick N Gorgani
1Department of Immunology, Genentech Inc., 1 DNA Way, South San Francisco, CA 94080, USA.
Cell
|March 15, 2006
Summary
Researchers identified Complement Receptor of the Immunoglobulin superfamily (CRIg) on Kupffer cells. This receptor is crucial for clearing complement C3-opsonized particles, preventing infection and mortality.
Area of Science:
- Immunology
- Cell Biology
Background:
- The complement system is vital for clearing pathogens and cellular debris.
- Kupffer cells are key in clearing circulating particles, but the receptors involved were unknown.
Purpose of the Study:
- To identify and characterize complement receptors on Kupffer cells responsible for particle clearance.
Main Methods:
- Identification and characterization of a novel complement receptor, CRIg.
- Assessing the role of CRIg in Kupffer cell phagocytosis using CRIg-deficient mice.
Main Results:
- CRIg binds complement fragments C3b and iC3b.
- CRIg expression on Kupffer cells is essential for phagocytosing C3-opsonized particles.
- CRIg deficiency leads to impaired pathogen clearance, increased infection, and mortality.
Conclusions:
- CRIg is a critical complement receptor on Kupffer cells.
- CRIg mediates the rapid clearance of C3-opsonized particles from circulation.
- CRIg plays a dominant role in innate immunity against complement-tagged pathogens.
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