Density heterogeneities of hepatitis C virus in human sera due to the binding of ?-lipoproteins and immunoglobulins

Abstract
Heterogeneities in the density of hepatitis C virus RNA-carrying material (HCV-RNA-CM) found in human sera (1.03–1.20 g/cm3) are attributed to the binding of low-density lipoproteins and/or of IgG. In some sera HCV-RNA-CM seems to be nearly totally bound to β-lipoproteins and cannot be precipitated by anti-IgG (γ); in others more than 95% of HCV-RNA-CM is bound to IgG and cannot be precipitated by anti-β-lipoprotein. Furthermore, there are sera from which HCV-RNA-CM can be completely be precipitated by either anti-β-lipoprotein or anti-IgG (γ), pointing to a binding of the two serum proteins to the same HCV-RNA-CM. There are other sera from which HCV-RNA-CM can be partially precipitated by the one or the other antiserum, leaving behind fractions, which are bound to β-lipoprotein or to IgG. HCV-RNA-CM cannot be precipitated from some sera either by anti-β-lipoprotein or by anti-IgG (γ).