Serum lipoprotein measurement--liquid chromatography and sequential floatation (ultracentrifugation) compared.

An HPLC method [J. Biochem. (Tokyo) 91:1381, 1982] was used for evaluating serum lipoproteins, with on-line monitoring of either cholesterol or phospholipids. Five well-distinguished lipoprotein fractions were observed, based on their particle sizes. Serum of 15 normal persons, 12 subjects with various types of hyperlipidemia, 20 patients with various liver diseases, and two cases of familial LCAT deficiency were examined and the results compared with those by a sequential ultracentrifugal floatation technique. In the normal group, the amounts of fractions 2, 3, and 4 by the HPLC method correlated well with concentrations of the LDL, HDL2, and HDL3 fractions as measured by the ultracentrifugal method, respectively. In the hyperlipidemic group, similar good correlations were observed between fractions 1, 2, 3, 4 and chylomicrons + VLDL, LDL, HDL2, and HDL3 fractions, respectively. For those with liver diseases or LCAT deficiency, the corresponding fractions correlated less well, and characteristically the elution profile of lipoproteins in these groups showed heterogeneity of particle size within each lipoprotein density class, especially in LDL and HDL2.