Cholesteryl ester transfer protein. Computer illustration of a section through a molecule of cholesteryl ester transfer protein (CETP) bound to a high-density lipoprotein (HDL, yellow). Lipoproteins are the major carriers of cholesterol in the blood and are mainly composed of lipids. CETP, also called plasma lipid transfer protein, is a plasma protein that facilitates the transport of cholesteryl esters and triglycerides between the lipoproteins.