Apolipoprotein distribution in human lipoproteins separated by XXXX gradient gel electrophoresis.

@entity15783 @entity2204 @entity5704 @entity755 @entity2975 @entity1675 @entity16990 @entity3294
The heterogeneity of serum lipoproteins (excluding very low density (VLDL) and intermediate density (IDL) lipoproteins) and that of lipoproteins secreted by HepG2 cells has been studied by immunoblot analysis of the apolipoprotein composition of the particles separated by @entity2975 gradient gel electrophoresis (GGE) under nondenaturing conditions. The reactions of antibodies to @entity1675 , @entity3294 , @entity2204 , @entity755 , @entity16990 , and @entity15783 have revealed discrete bands of particles which differ widely in size and apolipoprotein composition. GGE of native serum lipoproteins demonstrated that @entity3294 is present in lipoproteins of limited size heterogeneity (apparent molecular mass 345,000 to 305,000) and that @entity755 is present in low density lipoproteins (LDL) and absent from all smaller or denser lipoproteins. In contrast, serum @entity1675 , E, D, and A-IV are present in very heterogeneous particles. Serum @entity1675 is present mainly in particles of 305 to 130 kDa where it is associated with @entity3294 , and in decreasing order of immunoreactivity in particles of 130-90 kDa, 56 kDa, 815-345 kDa, and finally within the size range of LDL, all regions where there is little detectable @entity3294 . Serum @entity2204 is present in three defined fractions, one within the size range of LDL, one containing heterogeneous particles between 640 and 345 kDa, and one defined fraction at 96 kDa. Serum @entity16990 is also present in three defined fractions, one comigrating with LDL, one containing heterogeneous particles between 390 and 150 kDa, and one band on the migration front. Most of serum @entity15783 is contained in a band comigrating with albumin. GGE of centrifugally prepared LDL shows the presence of @entity755 , @entity2204 , and @entity16990 , but not that of @entity1675 . However, the particles containing @entity1675 , which, in serum, migrated within the LDL size range and as bands of 815 to 345 kDa, were recovered upon centrifugation in the d greater than 1.21 g/ml fraction. GGE of high density lipoproteins (HDL) indicated that most of @entity1675 , @entity5704 , and A-IV were present in lipoproteins of the same apparent molecular mass (390-152 kDa). @entity16990 tended to be associated with large HDL, and this was also significant for HDL @entity2204 , which is present in lipoproteins ranging from 640 to 275 kDa. GGE of very high density lipoproteins (VHDL) presented some striking features, one of which was the occurrence of apolipoproteins in very discrete bands of different molecular mass. @entity3294 was bimodally distributed at 250-175 kDa and 175-136 kDa, the latter fraction also containing @entity1675 .(ABSTRACT TRUNCATED AT 400 WORDS)
