A MACROPHAGE RECEPTOR FOR OXIDIZED LOW-DENSITY-LIPOPROTEIN DISTINCT FROM THE RECEPTOR FOR ACETYL LOW-DENSITY-LIPOPROTEIN - PARTIAL-PURIFICATION AND ROLE IN RECOGNITION OF OXIDATIVELY DAMAGED CELLS

The binding and uptake of oxidatively modified low density lipoprotein (OxLDL) by mouse peritoneal macrophages occurs, in part, via the well characterized acetyl LDL receptor, However, several lines of evidence indicate that as much as 30-70% of the uptake can occur via a distinc t receptor that recognizes OxLDL with a higher affinity than it recogn izes acetyl LDL, We describe the partial purification and characteriza tion of a 94- to 97-kDa plasma membrane protein from mouse peritoneal macrophages that specifically binds OxLDL. This receptor is shown to b e distinct from the acetyl LDL receptor as well as from two other macr ophage proteins that also bind OxLDG - the Fc gamma RII receptor and C D36, We suggest that this OHLDL-binding membrane protein participates in uptake of OxLDL by murine macrophages and also represents a recepto r responsible for macrophage binding and phagocytosis of oxidatively d amaged cells.