Mechanisms
A polyclonal-antibody immunoradiometric assay detects CETP down to 0.1 nanograms with under 9% variability (J Lipid Res 1993)
Original title: Polyclonal antibody-based immunoradiometric assay for quantification of cholesteryl ester transfer protein
To enable accurate quantification of CETP across clinical settings, CETP was purified from human plasma to apparent homogeneity and used to raise polyclonal anti-CETP antibodies in rabbits, whose specificity was confirmed by inhibition assays and immunoblotting. The antibodies were affinity-purified on CETP-Sepharose before use in a new immunoradiometric assay (IRMA), which achieved a sensitivity of 0.1 ng and intra- and interassay coefficients of variation of 2.9% and 8.0%. In 30 normolipidemic healthy subjects, mean plasma CETP concentration was 1.1 plus or minus 0.22 micrograms/ml, ranging from 0.644 to 1.694 micrograms/ml, and correlated well with CETP activity measured in the same samples (r equals 0.85), providing a sensitive new tool for quantifying CETP in plasma.
Original abstract
Cholesteryl ester transfer protein (CETP) catalyzes the transfer of neutral lipids among plasma lipoproteins and in this way plays a prominent role in cholesterol metabolic routing and, thus, probably for atherosclerosis. Studies of this important protein in various clinical settings require the ability to accurately quantify CETP in plasma. In order to gain access to such a capability, an immunoradiometric assay (IRMA) for quantification of CETP was developed. CETP was purified from human plasma to apparent homogeneity and used for raising anti-CETP antibodies in rabbits. The specificity of the polyclonal antiserum obtained was demonstrated by inhibition assays and immunoblot analysis. Before use in the CETP-IRMA, the antibodies were affinity-purified by chromatography on CETP-Sepharose. Sensitivity of the CETP-IRMA was 0.1 ng, and intra- and interassay coefficients of variation were 2.9 and 8.0%, respectively. In 30 normolipidemic healthy subjects, the mean (+/- SD) CETP concentration was 1.1 (+/- 0.22) micrograms/ml of plasma; individual values ranged from 0.644 to 1.694 micrograms CETP/ml and agreed well with measurements of CETP activity of the same samples (r = 0.85).
Summary written by cetpinhibition.org from the published abstract; figures as published. Page updated 18 August 2026. Methods.