MARCO

MARCO is also known as Scavenger receptor class A member 2 and SCARA2. Pattern recognition receptor (PRR) which binds Gram-positive and Gram-negative bacteria. Also plays a role in binding of unopsonized particles by alveolar macrophages. Binds to the secretoglobin SCGB3A2. MARCO ligation promotes the production of inflammatory mediators by macrophages. MARCO mediated internalization of some ligands prevents their activation of cell surface TLR4 but enables their activation of intracellular TLR3. MARCO contributes to the clearance of apoptotic cells and inhaled bacteria, mast cell mediated silicosis, and the amelioration of allergen or ozone induced lung inflammation. It is required for the organization of the splenic marginal zone and the interaction of splenic macrophages and B cells.