MACROPHAGE-COLONY-STIMULATING FACTOR SELECTIVELY ENHANCES MACROPHAGE SCAVENGER RECEPTOR EXPRESSION AND FUNCTION

Regulation of macrophage scavenger receptor (MSR) activity may be an i mportant determinant of the extent of atherogenesis. The effect of mac rophage-colony-stimulating factor (M-CSF) on this pathway was studied using a recently developed monoclonal antibody to murine MSR. M-CSF ma rkedly and selectively increased MSR synthesis in murine macrophages: posttranslationally, the receptor appeared more stable and shifted to a predominantly surface distribution. Functionally, M-CSF enhanced mod ified lipoprotein uptake and increased divalent cation-independent adh esion in vitro. These results suggest a plausible mechanism whereby M- CSF production in the atheromatous plaque microenvironment could promo te the recruitment and retention of mononuclear phagocytes and subsequ ent foam cell formation.