Characterization of apoA-IV-containing lipoprotein particles isolated from human plasma and interstitial fluid.
Apolipoprotein (apo) A-IV has been proposed to play a role in reverse cholesterol transport. ApoA-IV-containing lipoprotein particles (A-IVLp) were isolated from human plasma and interstitial fluid and characterized by immunoaffinity chromatography. Two major A-IVLp subpopulations, lipoprotein particles containing apoA-IV with apoA-I (LpA-I:A-IV) and lipoprotein particles containing apoA-IV without apoA-I (LpA-IV), were identified. The larger subpopulation of A-IVLp is the LpA-IV that represents 70% (protein mass) of the initial particles. Only 5.8% of apoA-IV was recovered in the retained fraction after affinity chromatography with an anti-apoA-I immunosorbent. ApoA-I, apoA-II, apoA-IV, apoB, apoC-III, apoD, apoE, apoH, lecithin: cholesterol acyltransferase (LCAT), cholesteryl ester transfer (CET) protein, proline-rich protein, and a protein of Mr 59,000 were detected in the A-IVLp. These particles contain more than 20% triglycerides (lipid mass). ApoA-IV-containing particles that were isolated from plasma are heterogeneous in size, consisting of two major populations with Stokes' diameters of 10.3 nm and 9.3 nm. Both subpopulations of A-IVLp contain LCAT and CET activities and promote cholesterol efflux from cholesterol-preloaded adipose cells. These data support the hypothesis that A-IVLp particles may be involved in reverse cholesterol transport.
Duverger
N
N
Institut Pasteur, INSERM, Lille, France.
Ghalim
N
N
Ailhaud
G
G
Steinmetz
A
A
Fruchart
J C
JC
Castro
G
G
D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism; D000328:Adult; D001054:Apolipoproteins A / Q000378:metabolism / Q000502:physiology*; D001798:Blood Proteins / Q000737:chemistry; D002352:Carrier Proteins / Q000097:blood; D002460:Cell Line; D055598:Chemical Phenomena; D002621:Chemistry; D002784:Cholesterol / Q000378:metabolism; D053480:Cholesterol Ester Transfer Proteins; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D005110:Extracellular Space / Q000378:metabolism*; D006023:Glycoproteins; D006801:Humans; D007158:Immunologic Techniques; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000378:metabolism; D013234:Stem Cells / Q000378:metabolism
D001054:Apolipoproteins A; D001798:Blood Proteins; C506642:CETP protein, human; D002352:Carrier Proteins; D053480:Cholesterol Ester Transfer Proteins; D006023:Glycoproteins; C022205:apolipoprotein A-IV; D002784:Cholesterol; D007862:Phosphatidylcholine-Sterol O-Acyltransferase