title: A 70-kDa apolipoprotein designated ApoJ is a marker for subclasses of human plasma high density lipoproteins.
abstract: A new apolipoprotein, termed apolipoprotein J (apoJ), was purified from human plasma by immunoaffinity chromatography. ApoJ is a glycoprotein consisting of disulfide-linked subunits of 34-36 and 36-39 kDa. Each subunit is glycosylated and has a pI range of 4.9-5.4. ApoJ exists in the plasma associated with high density lipoproteins (HDL) and specifically with subclasses of HDL which also contain apoAI and cholesteryl ester transfer protein activity. Immunoaffinity purified apoJ-HDL subclasses have apparent molecular masses of 80, 160, 240, 340, and 520 kDa, as determined by gradient gel electrophoresis. By negative staining electron microscopy, apoJ-HDL range in diameter from 5 to 16 nm. Fractionation of plasma by vertical gradient density centrifugation revealed apoJ-HDL in HDL2 (d 1.063-1.125 g/ml) with the majority overlapping HDL3 (d 1.125-1.21 g/ml) and very high density lipoprotein (d 1.21-1.25 g/ml). The bimodal density distribution of apoJ-HDL suggests that these subclasses have a unique metabolic relationship and may play a role in the transport of cholesterol from peripheral tissues to the liver.
authors.affiliation: Department of Pharmacology, University of Cincinnati, Ohio 45267.
authors.forename: H V
authors.initials: HV
authors.lastname: de Silva
authors.forename: W D
authors.initials: WD
authors.lastname: Stuart
authors.forename: C R
authors.initials: CR
authors.lastname: Duvic
authors.forename: J R
authors.initials: JR
authors.lastname: Wetterau
authors.forename: M J
authors.initials: MJ
authors.lastname: Ray
authors.forename: D G
authors.initials: DG
authors.lastname: Ferguson
authors.forename: H W
authors.initials: HW
authors.lastname: Albers
authors.forename: W R
authors.initials: WR
authors.lastname: Smith
authors.forename: J A
authors.initials: JA
authors.lastname: Harmony
mesh_terms: D000911:Antibodies, Monoclonal; D001053:Apolipoproteins / Q000097:blood* / Q000302:isolation & purification; D015415:Biomarkers / Q000097:blood*; D002352:Carrier Proteins / Q000097:blood; D053480:Cholesterol Ester Transfer Proteins; D002846:Chromatography, Affinity; D051152:Clusterin; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins; D006801:Humans; D015151:Immunoblotting; D008075:Lipoproteins, HDL / Q000097:blood* / Q000145:classification / Q000302:isolation & purification / Q000648:ultrastructure; D008077:Lipoproteins, LDL / Q000097:blood; D008854:Microscopy, Electron; D018832:Molecular Chaperones; D008970:Molecular Weight
chemical_list: D000911:Antibodies, Monoclonal; D001053:Apolipoproteins; D015415:Biomarkers; C506642:CETP protein, human; C495242:CLU protein, human; D002352:Carrier Proteins; D053480:Cholesterol Ester Transfer Proteins; D051152:Clusterin; D006023:Glycoproteins; D008075:Lipoproteins, HDL; D008077:Lipoproteins, LDL; D018832:Molecular Chaperones