Details

Autor(en) / Beteiligte

• Gorgani, Nick N
• He, Jeannie Q
• Katschke, Kenneth J., Jr
• Helmy, Karim Y
• Xi, Hongkang
• Steffek, Micah
• Hass, Philip E
• van Lookeren Campagne, Menno

Titel

Complement Receptor of the Ig Superfamily Enhances Complement-Mediated Phagocytosis in a Subpopulation of Tissue Resident Macrophages

Ist Teil von

• The Journal of immunology (1950), 2008-12, Vol.181 (11), p.7902-7908

Ort / Verlag

United States: Am Assoc Immnol

Erscheinungsjahr

2008

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• An important function of the complement cascade is to coat self and foreign particles with C3-proteins that serve as ligands for phagocytic receptors. Although tissue resident macrophages play an important role in complement-mediated clearance, the receptors coordinating this process have not been well characterized. In the present study, we identified a subpopulation of resident peritoneal macrophages characterized by high expression of complement receptor of the Ig superfamily (CRIg), a recently discovered complement C3 receptor. Macrophages expressing CRIg showed significantly increased binding and subsequent internalization of complement-opsonized particles compared with CRIg negative macrophages. CRIg internalized monovalent ligands and was able to bind complement-opsonized targets in the absence of Ca(2+) and Mg(2+), which differs from the beta(2)-integrin CR3 that requires divalent cations and polyvalent ligands for activation of the receptor. Although CRIg dominated in immediate binding of complement-coated particles, CRIg and CR3 contributed independently to subsequent particle phagocytosis. CRIg thus identifies a subset of tissue resident macrophages capable of increased phagocytosis of complement C3-coated particles, a function critical for immune clearance.