Lipoproteins and Lipid Transport

Lipids are transported in blood plasma in association with proteins. Some polar lipids are transported by albumin (free fatty acids, bile acids) or by specific binding proteins (retinol-binding protein). Nonpolar lipids are transported in large complexes containing polar lipids and specific apoproteins (which serve functions beyond that of “packaged”). These complexes comprise the macromolecular particles that we generally think of when we apply the term “lipoproteins” to blood plasma and other extracellular fluids. These lipoproteins and their role in transport of nonpolar lipids are the subject of this short and eclectic review.