HDL biology
CETP is locally synthesized and secreted within the human brain, not just imported from plasma (Int J Clin Lab Res 1992)
Original title: Cholesteryl ester transfer protein in human brain
Cholesteryl ester transfer activity was measured in cerebrospinal fluid and plasma from ten neurologically normal subjects to test whether the brain has its own active cholesteryl ester transfer system. Cholesteryl ester transfer activity was readily detectable in cerebrospinal fluid, and this activity was completely abolished by a specific antibody against plasma CETP. Cerebrospinal fluid transfer activity was about 12% of plasma levels, whereas cerebrospinal fluid albumin was only about 0.6% of plasma levels, a discrepancy suggesting direct CETP synthesis within the brain rather than simple diffusion from plasma. Cholesteryl ester transfer activity was also detected in conditioned medium from human neuroblastoma and neuroglioma cells and from sheep choroid plexus. The authors conclude that CETP is synthesized and secreted within the brain, where it may play an important role in transporting and redistributing lipids within the central nervous system.
Original abstract
The evidence that apolipoproteins are found in the cerebrospinal fluid and low-density lipoprotein receptor is found in the brain suggests that the brain may have an active lipid transport system. In plasma, cholesteryl ester transfer protein mediates the exchange and net transfer of cholesteryl ester and triglycerides among lipoproteins. Cholesteryl ester transfer activity was measured in the cerebrospinal fluid and plasma of ten neurologically normal subjects. Cholesteryl ester transfer activity was readily detectable in cerebrospinal fluid (7.4 +/- 13% cholesteryl ester was transferred per 20 microliters), and this activity was completely abolished with specific antibody against the plasma cholesteryl ester transfer protein. The concentration of cholesteryl ester transfer activity in the cerebrospinal fluid was about 12% of that found in plasma, whereas the concentration of albumin in cerebrospinal fluid was only about 0.6% of that in plasma, suggesting direct synthesis of cholesteryl ester transfer protein within the brain. Cholesteryl ester transfer activity was found in conditioned medium from human neuroblastoma and neuroglioma cells and sheep choroid plexus. The data suggest that cholesteryl ester transfer protein is synthesized and secreted in the brain. This protein could play an important role in the transport and redistribution of lipids within the central nervous system.
Summary written by cetpinhibition.org from the published abstract; figures as published. Page updated 19 August 2026. Methods.