Specific sorbent of apolipoprotein B-containing lipoproteins for plasmapheresis. Characterization and experimental use in hypercholesterolemic rabbits.

Dextran sulfate was covalently bound to cellulose beads (LA01) and used as the specific sorbent of apolipoprotein B-containing lipoproteins. The binding profiles of very low density, low density, and high density lipoproteins to the material were consistent with simple Langmuir adsorption isotherms. Although the affinities of all lipoproteins for the sorbent were roughly similar, the surface area available for high density lipoprotein binding was much smaller than that for very low and low density lipoproteins (29, 927, and 1934 m2/liter of swollen beads, respectively). When human plasma was passed through a sorbent column, very low and low density lipoproteins were selectively adsorbed, while almost all the high density lipoproteins were recovered from the column together with the other major plasma components. An extracorporeal circulation system with this sorbent was used for the treatment of hypercholesterolemic rabbits (diet-induced and homozygous WHHL). With a 25 ml sorbent column, very low and low density lipoproteins were selectively removed from rabbit plasma, resulting in a reduction of plasma cholesterol concentration by 300 mg/dl.