Minimally modified low density lipoprotein induces monocyte chemotactic protein 1 in human endothelial cells and smooth muscle cells.
After exposure to low density lipoprotein (LDL) that had been minimally modified by oxidation (MM-LDL), human endothelial cells (EC) and smooth muscle cells (SMC) cultured separately or together produced 2- to 3-fold more monocyte chemotactic activity than did control cells or cells exposed to freshly isolated LDL. This increase in monocyte chemotactic activity was paralleled by increases in mRNA levels for a monocyte chemotactic protein 1 (MCP-1) that is constitutively produced by the human glioma U-105MG cell line. Antibody that had been prepared against cultured baboon smooth muscle cell chemotactic factor (anti-SMCF) did not inhibit monocyte migration induced by the potent bacterial chemotactic factor f-Met-Leu-Phe. However, anti-SMCF completely inhibited the monocyte chemotactic activity found in the media of U-105MG cells, EC, and SMC before and after exposure to MM-LDL. Moreover, monocyte migration into the subendothelial space of a coculture of EC and SMC that had been exposed to MM-LDL was completely inhibited by anti-SMCF. Anti-SMCF specifically immunoprecipitated 10-kDa and 12.5-kDa proteins from EC. Incorporation of [35S]methionine into the immunoprecipitated proteins paralleled the monocyte chemotactic activity found in the medium of MM-LDL stimulated EC and the levels of MCP-1 mRNA found in the EC. We conclude that (i) SMCF is in fact MCP-1 and (ii) MCP-1 is induced by MM-LDL.
Department of Medicine, UCLA School of Medicine 90024-1679.
S D
SD
Cushing
J A
JA
Berliner
A J
AJ
Valente
M C
MC
Territo
M
M
Navab
F
F
Parhami
R
R
Gerrity
C J
CJ
Schwartz
A M
AM
Fogelman
D001011:Aorta / Q000187:drug effects / Q000378:metabolism*; D001483:Base Sequence; D015152:Blotting, Northern; D002478:Cells, Cultured; D018932:Chemokine CCL2; D002630:Chemotactic Factors / Q000096:biosynthesis* / Q000235:genetics / Q000494:pharmacology; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D004247:DNA / Q000235:genetics; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D008077:Lipoproteins, LDL / Q000494:pharmacology*; D008715:Methionine / Q000378:metabolism; D008969:Molecular Sequence Data; D009000:Monocytes / Q000187:drug effects / Q000502:physiology; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism*; D015345:Oligonucleotide Probes; D010084:Oxidation-Reduction; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000235:genetics; D013462:Sulfur Radioisotopes; D014158:Transcription, Genetic / Q000187:drug effects
D018932:Chemokine CCL2; D002630:Chemotactic Factors; D008077:Lipoproteins, LDL; D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D013462:Sulfur Radioisotopes; D012313:RNA; D004247:DNA; D008715:Methionine