Low-density lipoprotein apheresis and changes in plasma components.

Abstract

Several different techniques of low-density lipoprotein (LDL) apheresis are available for management of severe hypercholesterolemia. Among them, the adsorption system with a dextran-sulfate cellulose (DSC) column is most widely used. In addition to adsorption of LDL, DSC adsorbs plasma constituents that have the following characteristics: proteins containing apolipoprotein B (Lp[a]); proteins involved in the initial contact phase of the intrinsic coagulation pathway (coagulation factor XII, high-molecular-weight kininogen and prekallikrein); factors with lipophilic characteristics (coagulation factor VII, coagulation factor VIII, and vitamin E); and proteins with adhesive or other characteristics (von Willebrand factor, fibronectin, serum amyloid P component, hepatocyte growth factor). The adsorption of these proteins seems to ameliorate prevention or regression of atherosclerosis. Moreover, plasma treatment by the DSC column may be useful for treatment of inexorable diseases, such as amyloidosis. On the other hand, the DSC column generates bradykinin by activation of the initial contact phase of the intrinsic coagulation pathway. Bradykinin generation may explain the functional improvement in the circulatory system, as well as hypotension during LDL apheresis, which is observed in patients taking ACE inhibitors.