Two lipoprotein species were isolated by starch block electrophoresis from the very low density lipoproteins (VLDL) (Sf 20-400) of patients with type III hyperlipoproteinemia. One of these, α2-VLDL, had a content of lipid and protein and physical characteristics similar to VLDL from normal subjects or patients with other forms of hyperglyceridemia. The other species, β-VLDL, contained more cholesterol and less triglyceride in relation to the protein, than normal VLDL. Only the apoprotein of low density lipoprotein was immunochemically detectable in the β-VLDL; the proteins in the α2-VLDL reacted with antisera specific for low density lipoprotein and high density lipoprotein. The electrophoretic mobility of β-VLDL was similar to that of low density lipoprotein and significantly less than that of α2-VLDL. Isolated β-VLDL had a lesser mean flotation rate than α2-VLDL, but both α2- and β-VLDL were found throughout the Sf 20-400 flotation range.
Steven Quarfordt, Robert I. Levy, Donald S. Fredrickson