The Effect of Beta-Lipoprotein on Antistreptolysin-O Antibody Titers

Abstract

The relationship between antistreptolysin-O (ASLO) titers and β-lipoprotein were examined The following results were obtained. 1. Fifty-three children with unmeasurably low ASLO titers had variable β-lipoprotein concentrations which were within normal ranges. 2. Streptococcal infections in the children correlated well with the elevation of ASLO titers, but β-lipoprotein concentration in these sera did not show any correlation with the behavior of ASLO titers. 3. From the Sephadex G 200 gel filtration chromatographical study, no ASLO activities were found in the fraction containing β-lipoprotein except in some special cases that had the IgM ASLO antibody. 4. The inhibitory effect of β-lipoprotein upon hemolysis by streptolysin-O was incomplete and its effect decreased with a pro longed incubation time. 5. The partially purified β-lipoprotein had no effect upon the hemolytic activity of streptolysin-O, when the ASLO titers were measured by the method of 100% inhibition cf hemolysis. From these observations, it was concluded that the ASLO antibody titers were truly relate to streptococcal infection and not influenced by the presence of β-lipoprotein if the ASLO titers wer measured by the 100% inhibition of hemolysis.