Isolation of low density lipoprotein subfraction containing apolipoprotein B-like protein from Japanese eel Anguilla japonica plasma using dextran sulfate cellulose.

Japanese eel (Anguilla japonica) possessed a unique lipoprotein profile in their plasma, reflecting high utilization of lipids. Low density lipoprotein (LDL) fraction isolated at the densities from 1.006 to 1.085 g/ml comprised the heterogeneous components with molecular weight (Mr) 1200 K, 470 K, and 250 K. LDL subfraction with Mr 1200 K was completely adsorbed to dextran sulfate cellulose (DSC) column which had been developed for LDL apheresis treatment of the patients with familial hypercholesterolemia, while LDL subfractions with Mr 470 K and 250 K had no affinity for the DSC column. LDL subfractions with Mr 470 K and 250 K were floated and settled, respectively, by centrifuging the unbound fraction of DSC column at a density of 1.063 g/ml. LDL subfraction with Mr 1200 K possessed apolipoprotein (apo) B-like protein of Mr 230 K, while apo A-I- and A-II-like proteins of Mr 25 K and 14 K were the main components in LDL subfractions with Mr 470 K and 250 K. The presence of apo B-like protein seemed to be responsible for the adsorption of LDL subfraction with Mr 1200 K for the DSC column. LDL subfractions with Mr 470 K and 250 K seemed to belong to high density lipoprotein (HDL) with respect to molecular weights and apolipoprotein features. To our knowledge, this is the first report of the separation of LDL and HDL from the plasma of Japanese eels using the DSC column.