At least 9 distinct polymorphic forms of apolipoproteins are known. The apolipoproteins act as stabilizers of the intact lipoprotein particles. Quantitative measurements of HDL, LDL and VLDL particles in human serum are often used to estimate an individuals' relative risk of coronary heart disease. In addition, quantitative immunological measurements of certain apolipoproteins (especially A-1 and B) have been suggested to be more accurate estimators of coronary heart disease than measurements of lipoprotein particles (especially HDL and LDL). This apo-lipoprotein antibody is derived from human plasma by density gradient ultracentrifugation and HPLC.
