Characterization of apolipoprotein E-rich high density lipoproteins in familial lecithin:cholesterol acyltransferase deficiency.
We have isolated and charachterized a subfraction of high density lipoproteins, rich in apolipoprotein E, from the plasma of patients afflicted with familial lecithin:cholesterol acyltransferase deficiency. Prepared by successive ultracentrifugal flotation, affinity chromatography on heparin-agarose, and affinity chromatography on conconavalin A-agarose, the subfraction contained disc-shaped lipoproteins that measured 14--40 nm in diameter and 4.4--4.5 nm in thickness. The major components were apolipoprotein E, phosphatidylcholine, and unesterified cholesterol, though other apolipoproteins and lipids were present in small amounts. A second subfraction of high density lipoproteins, isolated during the chromatography, contained apolipoproteins A-I and A-II, but no apolipoprotein E. This subfraction included disc-shaped lipoproteins, 13--24 nm in diameter, as well as small round particles, 5.7 nm in diameter. Both subfractions contained similar proportions of total protein relative to lipid, similar amounts of unesterified cholesterol relative to phosphatidylcholine, and a similar distribution of phosphatidylcholine fatty acid.
D000328:Adult; D001053:Apolipoproteins / Q000097:blood* / Q000302:isolation & purification; D001057:Apolipoproteins E; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D003208:Concanavalin A; D005260:Female; D006493:Heparin; D006801:Humans; D007009:Hypolipoproteinemias / Q000097:blood*; D007863:Lecithin Cholesterol Acyltransferase Deficiency / Q000097:blood*; D008075:Lipoproteins, HDL / Q000097:blood*; D008854:Microscopy, Electron; D008875:Middle Aged
D001053:Apolipoproteins; D001057:Apolipoproteins E; D008075:Lipoproteins, HDL; D003208:Concanavalin A; D006493:Heparin