The present invention provides compositions and methods for modulating one or more phenotypes of a macrophage-related cell, e.g., a macrophage. The invention further provides methods of treating disease by modulating macrophage phenotype. Representative phenotypes include pro-inflammatory, anti-inflammatory, immunogenic, tolerogenic, tissue-destructive, tissue restorative, cytotoxic, migratory, bone-resorbing, pro-angiogenic, anti-angiogenic, suppressor, antigen presentation, or phagocytic. Representative diseases include atherosclerosis, arthritis, and multiple sclerosis.
