The Use of Hemolysin Inhibition in the Study of Experimental And Clinical Hyperlipemia: THE NON-SPECIFIC INHIBITION OF STREPTOLYSIN O BY SERUM LIPOPROTEINS1

Abstract

A study was made of the inhibition of 2 cholesterol sensitive hemolysins, streptolysin O and saponin by the sera of rabbits with experimentally induced hyperlipemia and by the sera of patients with disturbances in lipid metabolism. Certain types of serum showed distinctive preperties as inhibitors of these hemolysins. Streptolysin O was strongly inhibited by the sera of rabbits fed cholesterol. This inhibition was enhanced by the administration of heparin. Inhibition of streptolysin O hemolysis appeared to be related to a high ratio of the concentration of serum cholesterol to serum phospholipids. Human hypercholesterolemic sera did not inhibit streptolysin O except in rare instances where the ratio of serum cholesterol to phospholipid was unusually high. Enzymatic degradation of phospholipids by Clostridium welchii lecithinase resulted, in most instances, in marked increase in the inhibition of streptolysir O hemolysis. The inhibition of saponin hemolysis was quite different from that of streptolysin O. The inhibition of saponin appeared to be related in general to absolute cholesterol concentration rather than to cholesterol/phospholipid ratios. The property of streptolysin O inhibition by sera appears to be related closely to the chemical structure and physical state of serum lipoproteins.