An apolipoprotein A-I mimetic dose-dependently increases the formation of preβ1 HDL in human plasma

Preβ 1 HDL is the initial plasma acceptor of cell-derived cholesterol in reverse cholesterol transport. Recently, small amphipathic peptides composed of D-amino acids have been shown to mimic apolipoprotein A-I (apoA-I) as a precursor for HDL formation. ApoA-I mimetic peptides have been proposed to stimulate the formation of preβ 1 HDL and increase reverse cholesterol transport in apoE-null mice. The existence of a monoclonal antibody (MAb 55201) and a corresponding ELISA method that is selective for the detection of the preβ 1 subclass of HDL provides a means of establishing a correlation between apoA-I mimetic dose and preβ 1 HDL formation in human plasma. Using this preβ 1 HDL ELISA, we demonstrate marked apoA-I mimetic dose-dependent preβ 1 HDL formation in human plasma. These results correlated with increases in band density of the plasma preβ 1 HDL, when observed by Western blotting, as a function of increased apoA-I mimetic concentration. Increased preβ 1 HDL formation was observed after as little as 1 min and was maximal within 1 h. Together, these data suggest that a high-throughput preβ 1 HDL ELISA provides a way to quantitatively measure a key component of the reverse cholesterol transport pathway in human plasma, thus providing a possible method for the identification of apoA-I mimetic molecules.