Immunological evidence for the presence of B protein (apoprotein of Β-lipoprotein) in normal and abetalipoproteinemic plasma

Abstract

The antigenicity of Β-lipoprotein that had been chemically altered by acetylation or arsanilation was compared with that of native Β-lipoprotein, of lymph chylomicrons, of plasma proteins with d > 1.21, and of plasma from patients with abetalipoproteinemia. Chemical alteration causes structural changes in Β-lipoprotein which render it immunologically identical with a protein that is present both in normal plasma and in plasma from patients with abetalipoproteinemia. This protein has been identified by immunoelectrophoresis as a Β-globulin which does not stain for lipid. It is presumed to be the lipid-free apoprotein of Β-lipoprotein (B protein).The findings suggest that abetalipoproteinemia is not due to inability to synthesize B protein, but might instead be due to a defect in the formation of the complete Β-lipoprotein macromolecule.

Keywords

• Β-lipoprotein
• azo-Β-lipoprotein
• acetyl-Β-lipoprotein
• antisera
• B protein
• plasma 1.21 infranate