Localization of oxidized HDL in atheromatous plaques and oxidized HDL binding sites on human aortic endothelial cells.
We examined the localization of oxidized high-density lipoprotein (HDL) in atheromatous plaques and the oxidized HDL binding sites on endothelial cells. Histochemical analysis using CuSO4-oxidized HDL-specific 9F5-3a antibody indicated the presence of oxidized HDL in the intima of atheromatous plaques in human abdominal aortae. The cell surface binding of 125I-oxidized HDL to cultured human aortic endothelial cells (HAEC) was saturable, with an apparent dissociation constant (Kd) of 1.43 micromol/L. Competition for 125I-oxidized HDL binding was strong for oxidized HDL, moderate for native HDL and low for acetylated low-density lipoprotein (LDL) or oxidized LDL. Using oxidized HDL as a ligand for blotting, a major 130-kDa band was detected in HAEC. These results suggest that oxidized HDL and its putative binding protein are present in atheromatous plaques and endothelial cells, respectively.
Nakajima
T
T
First Department of Biochemistry, Saitama Medical School, Iruma-gun, Japan. takanori@saitama-med.ac.jp
Origuchi
N
N
Matsunaga
T
T
Kawai
S
S
Hokari
S
S
Nakamura
H
H
Inoue
I
I
Katayama
S
S
Nagata
A
A
Komoda
T
T
D000911:Antibodies, Monoclonal / Q000378:metabolism; D001011:Aorta / Q000378:metabolism*; D001161:Arteriosclerosis / Q000378:metabolism*; D001665:Binding Sites; D001667:Binding, Competitive; D015153:Blotting, Western; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007457:Iodine Radioisotopes; D007700:Kinetics; D008075:Lipoproteins, HDL / Q000032:analysis / Q000276:immunology / Q000378:metabolism*; D008565:Membrane Proteins / Q000032:analysis; D010084:Oxidation-Reduction; D011485:Protein Binding
D000911:Antibodies, Monoclonal; D007457:Iodine Radioisotopes; D008075:Lipoproteins, HDL; D008565:Membrane Proteins