(Circulation. 1999;100:1215-1222.)
© 1999 American Heart Association, Inc.
Basic Science Reports |
From the Vascular Medicine and Atherosclerosis Unit, Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Mass (M.A., S.J.V., S.S., E.R., P.L.), and the Departments of Medicine (M.B.T., J.T.F.) and Pathology (J.T.F.), Cardiovascular Institute, Mount Sinai School of Medicine, New York, NY.
Correspondence to Masanori Aikawa, MD, PhD, Vascular Medicine and Atherosclerosis Unit, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Ave, LMRC 309, Boston, MA 02115. E-mail maikawa{at}bics.bwh.harvard.edu
| Abstract |
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Methods and ResultsTo test the hypothesis that lipid lowering reduces TF expression and activity, we produced atheroma in rabbit aortas by balloon injury and cholesterol feeding for 4 months (Baseline group, n=15), followed by either a chow diet (Low group, n=10) or a continued high-cholesterol diet for 16 months (High group, n=5). Immunolocalization of TF, CD40L, and its receptor CD40 was quantified by computer-assisted color image analysis. Macrophages in atheroma of the Baseline and High groups strongly expressed TF. Intimal smooth muscle cells and endothelial cells also contained immunoreactive TF. Regions of expression of CD40L and CD40 colocalized with TF. Protein expression of TF diminished substantially in the Low group in association with reduced expression of CD40L and CD40. In situ binding of TF to factors VIIa and X, detected by digoxigenin-labeled factors VIIa and X, colocalized with TF protein in atheroma and decreased after lipid lowering. We also determined reduced TF biological activity in the Low group by use of a chromogenic assay. The level of TF mRNA detected by reverse transcriptionpolymerase chain reaction also decreased after lipid lowering.
ConclusionsThese results suggest decreased expression and activity of TF as a novel mechanism of reduced incidence of thrombotic complications of atherosclerosis by lipid lowering.
Key Words: atherosclerosis thrombosis hypercholesterolemia coagulation macrophages
| Introduction |
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Recent clinical trials have demonstrated that lipid lowering reduces the incidence of acute coronary events and mortality.15 16 17 18 19 These benefits do not appear to accrue so much from improvement in luminal caliber as from functional changes in the atheroma itself that are commonly called stabilization. However, the precise molecular and cellular mechanisms that underlie this lesion stabilization that leads to the striking clinical benefit remain speculative. We have demonstrated that lipid lowering by diet reduces macrophage accumulation, reduces proteinase expression and activity, and increases collagen content in atheroma of hypercholesterolemic rabbits, features that should reinforce the resistance of fibrous cap to rupture.20 We also have recently reported that dietary lipid lowering promotes accumulation of more mature smooth muscle cells (SMCs) in the fibrous cap of plaque.21 However, to date, no study has addressed the crucial issue of the thrombogenicity of plaque in relation to lipid lowering. Atheroma disruption by itself would have little clinical consequence were it not for inciting thrombus formation. Hence, this study tested the hypothesis that lipid lowering by diet reduces expression and activity of TF in atheroma of hypercholesterolemic rabbits.
Recent work from our laboratory identified interaction of CD40 ligand (CD40L, CD154) and its receptor CD40, an inflammatory signaling dyad found in human atheroma, as potentially the key trigger in TF expression by macrophages, the cell type most responsible for TF overexpression in atheroma.22 23 Therefore, we further tested the hypothesis that lipid lowering by diet reduces expression of CD40L and CD40 in the atheromata of these rabbits as a possible mechanism of any attenuation of TF. Our results shed considerable new light on the regulation of the thrombogenicity of the atherosclerotic plaque and provide new evidence regarding the mechanisms whereby lipid lowering can reduce the thrombotic complications of atheroma, such as unstable angina or myocardial infarction.
| Methods |
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Plasma Cholesterol and TG Levels
Peripheral blood was collected from the ear artery
under local anesthesia for measurement of plasma total
cholesterol (TC) and triglyceride (TG)
concentrations by enzymatic assays (Sigma).
Tissue Preparation
Rabbits were euthanized with sodium pentobarbital (120 mg/kg
IV). The proximal portion of the thoracic aorta (2 mm below the
ligamentum arteriosum) was excised and snap-frozen with OCT compound
(Sakura Finetek Inc) for fresh-frozen sections. The rest of the
thoracic aorta for detection of TF mRNA and activity was quickly frozen
with liquid nitrogen.
Immunohistochemistry
Monoclonal antibodies used in this study are as follows: mouse
monoclonal antibodies against rabbit TF (No. 4510, American
Diagnostica Inc), rabbit CD11b (Spring Valley
Laboratories), human
-smooth muscle actin (1A4, Dako Corp), and
human CD40 (MCA679, Serotec Ltd) and rat monoclonal anti-mouse CD40L
(M158, a gift of Immunex). Immunohistochemistry was performed on
fresh-frozen sections (6 µm) by the standard ABC method (Vector)
as described in our recent articles regarding other aspects of the same
animals.20 21 The percentages of immunopositive intimal
areas were measured with the Optimas 5.2 image analysis
system.20 21 The statistical testing used 1-way ANOVA
followed by Fisher's test. Linear regression analysis was
performed with the absolute positive areas of TF, CD40L, and CD40
staining.
In Situ Binding Assay of TF to Coagulation Factors VIIa and
X
Binding of TF to factors VIIa and X was detected in situ by use
of digoxigenin-labeled factors VIIa and X (DigVIIa and DigX) as
previously described.9 For detection of in situ DigVIIa
binding, fresh-frozen sections were fixed with acetone at -20°C for
10 minutes and incubated with 5 nmol/L DigVIIa in Tris-buffered saline
(pH 7.5) containing 5 mmol/L Ca2+ at 37°C
for 1 hour. Sections were treated with 4%
paraformaldehyde, incubated with a sheep Fab
anti-digoxigenin antibody conjugated with horseradish peroxidase at
37°C for 1 hour, and then incubated with 3,3'-diaminobenzidine for 10
minutes. Unlabeled factor VIIa was applied instead of DigVIIa as a
negative control. For DigX binding, sections were incubated with 10
nmol/L recombinant factor VIIa for 1 hour and then incubated with 10
nmol/L DigX at 37°C for 3 hours. Sections were fixed with 4%
paraformaldehyde and stained with anti-digoxigenin
antibody as mentioned above. DigX staining was also performed without
added recombinant factor VIIa as a negative control.
Immunohistochemistry for rabbit TF on serial sections was also
performed to determine colocalization of protein expression and in situ
binding of TF.
TF Activity Assay
TF activity was determined by chromogenic
measurement of generation of the factor Xa on total tissue
lysates.24 Frozen aortas were homogenized with
50 mmol/L Tris, 100 mmol/L NaCl, and 1% BSA, pH 7.6 (Tris
buffer) on ice and centrifuged at 10 000g at 4°C
for 15 minutes. Pellets were reconstituted with Tris buffer. Lysates
were incubated at room temperature with or without anti-rabbit TF
antibody (No. 4510, American Diagnostica) for 30 minutes.
Human factor VIIa, factor X, and the chromogenic substrate
(Spectrozyme fXa, American Diagnostica) were added, and
anti-rabbit TF antibodyinhibitable values were measured. Optical
density was measured at 410 nm, and total protein was measured by BCA
Kit (Pierce). Arterial TF activity was quantified by
reference to a standard curve constructed with recombinant human TF
(No. 4500L, American Diagnostica), and 30 ng/mL of this
protein yields a clotting time of 30 seconds. TF activity with a
30-second clotting time was defined as 1 U/mL, and arterial
TF is expressed as mU/100 µg protein.
RNA Extraction and Reverse TranscriptionPolymerase Chain
Reaction
Total RNA of aortas from 3 groups was extracted by the acid
guanidinium thiocyanatephenol-chloroform method.25 Total
RNA of rabbit peritoneal macrophages elicited by
lipopolysaccharide (1 µg/mL) was used as a positive control.
Two pairs of primers were designed to detect rabbit TF mRNA: sense,
5'-AAGCAGTGA-TTCCCTCTCG-3'; antisense,
5'-AACACAGCATTGGCAGCAG-3')26 and rabbit G3PDH as an
internal control: sense, 5'-GGAGCCAAA-AGGGTCATC-3'; antisense,
5'-CCAGTGAGTTTCCCGTTC-3').27 Each polymerase chain
reaction (PCR) cycle consisted of denaturing at 94°C for 30 seconds,
annealing at 56°C for 30 seconds, and elongation at 72°C for 60
seconds. PCR for TF and G3PDH was conducted for 40 cycles, and
products were electrophoresed on 2.0% agarose gel.
| Results |
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All Cell Types in Rabbit Atheroma Express TF and Its
Potent Inducers (CD40 Ligand and CD40)
Immunohistochemistry was performed to localize TF protein in
rabbit atheroma by use of the monoclonal antibody against
rabbit TF. In the Baseline group, after 4 months of atherogenic diet,
the aortic lesions contained prominent macrophages (identified
by immunostaining for CD11b) underlying an
-actinpositive SMC layer (Figure 2
).
Macrophages associated most prominently with TF. Intimal SMCs
and endothelial cells (ECs) also stained positively for
this potent procoagulant. The tunica media underlying
atheroma also stained weakly for TF. As in human arteries,
the adventitia contained TF.6 7 Double
immunostaining for TF and CD11b verified the
localization of TF in macrophages and SMCs in the baseline
lesion (Figure 2
, bottom right). Red indicates TF protein, and
blue indicates CD11b for macrophages. TF-expressing
macrophages stained purple as a result of a mixture of red and
blue, indicated by the arrow in the figure. Red spindle-shaped cells
are SMCs that stained positively for TF but not for CD11b. All vascular
cell types in the intima of the baseline lesion contained CD40L and
CD40, both of which colocalized with TF. Negative controls, in which
nonimmune mouse IgG or PBS was applied in place of the specific
monoclonal antibodies, abrogated the staining (data not shown).
|
TF Expression Decreases in Atheroma During Lipid
Lowering in Association With Reduced Expression of CD40L-CD40
After 16 months of continued high-cholesterol diet,
high levels of TF, CD40L, and CD40 expression persisted, predominantly
in macrophages but in intimal SMCs and ECs as well (Figure 3
). However, expression of TF, CD40L, and
CD40 by macrophages decreased in the intima of the Low-group
animals after 16 months of dietary lipid lowering in association with a
reduced number of macrophages (Figure 4
). SMCs and ECs also exhibited decreased
expression of TF, CD40L, and CD40.
|
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Quantitative color image analysis substantiated significant
reduction in TF, CD40L, and CD40 expression in the intima during lipid
lowering (Figure 5
). To test the
association of CD40L-CD40 and TF, we determined the correlation between
the immunopositive areas for these molecules (measured in square
millimeters). Linear regression analysis revealed a high
correlation of the amount of plaque area positive for CD40L and CD40
and that occupied by TF (R2=0.8003 and
R2=0.8047, respectively) (Figure 6
).
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Lipid Lowering Also Decreases Functional Activity of TF in
Plaques
In addition to assessing the presence of immunoreactive TF
protein, we sought evidence of TF function by evaluating the in situ
binding of the TF interacters, the coagulation factors VIIa and X,
detected by DigVIIa and DigX (Figure 7
).
DigVIIa and DigX colocalized with TF protein in atheroma of
the Baseline and High groups. However, DigVIIa and DigX binding
decreased in the intima of the Low-group animals, whereas the
adventitia stained positively, as expected. Similar results were
obtained from 5 animals from each group. A factor VIIa binding assay
using unlabeled factor VIIa and a DigX binding assay without added
recombinant factor VIIa showed no staining (data not shown).
|
We also determined enzymatic activity of TF using a
chromogenic assay that detects generation of factor Xa by
cleavage of factor X by TF
(Table
). TF activity was detected
in extracts of all aortas studied. However, lipid lowering by diet
produced statistically significant reduction in arterial TF
activity in aortic extracts from the Low group.
|
Lipid Lowering Reduces TF mRNA Expression in Aortas of
Hypercholesterolemic Rabbits
Reverse transcription (RT)-PCR was performed to determine whether
lipid lowering reduces TF expression at mRNA level in aortas of
hypercholesterolemic rabbits. TF mRNA (254 bp) was
detected in rabbit peritoneal macrophages elicited by
lipopolysaccharide and aortas from both the Baseline and High
groups (Figure 8
). However, expression
levels of TF mRNA decreased substantially in the Low group after 16
months of dietary lipid lowering, whereas G3PDH mRNA expression (346
bp) was similar in all 3 groups. PCR products were not detected on
all samples without RT reaction.
|
| Discussion |
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In the rabbits studied here, as in human atheroma, TF expression was detected predominantly on lesional macrophages in the Baseline and High groups by immunohistochemistry using anti-rabbit TF antibody. Some SMCs and ECs in atheroma also exhibited TF expression. To elucidate the state of TF identified by the antibody, we performed in situ binding assays for factors VIIa and X. These studies show that virtually all of the areas identified as containing TF antigen also bound factors VIIa and X. In addition, binding of factor X occurred only in the presence of VIIa. This suggests that the TF antigen contains an intact active site and thus is potentially active. In addition, we determined that TF activity generates factor Xa by cleaving factor X. Both protein expression and activity of TF decreased substantially during lipid lowering. Increased expression of TF and enhanced procoagulatory activity by monocytes/macrophages incubated with modified lipoproteins or free cholesterol have previously been reported.29 30 Lipid lowering may reduce lipid accumulation within atheroma and in turn decrease TF expression and activity.
A number of molecular mediators, including the
atheroma-related growth factors or inflammatory
cytokines, CD40L (CD 154), platelet-derived growth factor
(PDGF), tumor necrosis factor-
(TNF-
), and interleukin-1ß
(IL-1ß), may modulate TF expression in macrophages, SMCs, or
ECs.22 23 31 32 Increased production of such
mediators in atheroma should enhance TF expression in an
autocrine or paracrine manner. In this study, immunoreactive CD40L and
CD40 colocalized well with regions of TF protein expression in
atheroma, compatible with a role for CD40 ligation in
inducing TF expression in vitro.23 Lipid lowering markedly
reduced CD40L-CD40 expression within the rabbit atheroma,
illustrating 1 possible mechanism mediating the concomitant fall in TF
levels. Decreased expression of other cytokines also probably
contributes to reduced TF expression by cells in atheroma
during lipid lowering. In this study, expression of TF mRNA decreased
in aortas after lipid lowering. Intracellular regulation of TF gene
expression involves certain transcription factors, such as AP-1 and
nuclear factor (NF)-
B.31 Activated NF-
B
colocalizes with TF within atheroma.33 Further
experiments are required to determine whether dietary lipid lowering
interrupts the action of transcription factors that regulate genes that
contribute to plaque disruption or thrombus formation.
The reduction in TF reported here in part reflects diminished macrophage population during lipid lowering.20 This decrease in macrophage accumulation may have several molecular and cellular bases, analogous to those that regulate TF expression itself. For example, lipid lowering may reduce the local production of inflammatory cytokines, such as TNF and IL-1, which augment expression of leukocyte adhesion molecules on ECs, as well as of certain chemokines, such as MCP-1, involved in monocyte migration.34 35 Reduced proliferation of macrophages in response to factors such as macrophage colonystimulating factor or death of macrophages, including apoptotic attrition, may also contribute to reduced macrophage numbers during lipid lowering. The links between these various pathways and lipid lowering and their relative contributions to the decrease in macrophage number will require further investigation.
Schecter et al32 recently demonstrated that PDGF induces TF expression in SMCs. We have documented reduced PDGF B-chain expression during lipid lowering in these same rabbits.21 Thus, decreased expression of PDGF may limit TF expression by SMCs. We also have reported that lipid lowering promotes accumulation of mature SMCs expressing SMC-specific myosin heavy chain isoforms.21 An increase in number of SMCs with more normal phenotype by lipid lowering could also contribute to reduced expression of TF.
We recently reported that dietary lipid lowering reduces matrix-degrading enzymes expressed by macrophages and SMCs and promotes interstitial collagen accumulation in these rabbit atheroma, suggesting potential mechanisms of mechanical plaque stabilization.20 21 The present study addressed the other critical factor in the potential of a plaque to precipitate acute clinical consequences, namely its thrombogenicity. The present results suggest that dietary lipid lowering may limit coronary events not only by mechanically stabilizing vulnerable plaques but also by reducing their procoagulant capacity. Some evidence suggests that the clinical benefits of HMG-CoA reductase inhibitors may result from direct effects on lesional cells independent of reductions in LDL.17 19 36 Indeed, a recent report has shown reduced TF expression in isolated monocytic cells exposed to relatively high concentrations of HMG-CoA reductase inhibitors in vitro.37 Further in vivo experiments should address whether HMG-CoA reductase inhibitors have similar effects in vivo at doses relevant to clinical practice.
In conclusion, the present observations shed new light on the mechanisms by which lipid lowering may reduce clinical complications of atherosclerosis. This study supports the view that lipoproteins or their derivatives can promote local inflammation and thrombogenicity in the arterial wall and that lipid lowering in this context actually constitutes a form of anti-inflammatory and antithrombotic therapy. Our results provide an intellectual framework for understanding biological mechanisms underlying the clinical benefits of lipid lowering. By furnishing direct experimental evidence for reversibility of inflammatory and thrombogenic stimuli within atheroma, our findings should provide further impetus to treat hyperlipoproteinemia aggressively.
| Acknowledgments |
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Received December 29, 1998; revision received May 19, 1999; accepted May 19, 1999.
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W. Ni, S. Kitamoto, M. Ishibashi, M. Usui, S. Inoue, K.-i. Hiasa, Q. Zhao, K.-i. Nishida, A. Takeshita, and K. Egashira Monocyte Chemoattractant Protein-1 Is an Essential Inflammatory Mediator in Angiotensin II-Induced Progression of Established Atherosclerosis in Hypercholesterolemic Mice Arterioscler Thromb Vasc Biol, March 1, 2004; 24(3): 534 - 539. [Abstract] [Full Text] |
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T. Hayashi, D. Sumi, P. A.R Juliet, H. Matsui-Hirai, Y. Asai-Tanaka, H. Kano, A. Fukatsu, T. Tsunekawa, A. Miyazaki, A. Iguchi, et al. Gene transfer of endothelial NO synthase, but not eNOS, plus inducible NOS regressed atherosclerosis in rabbits Cardiovasc Res, February 1, 2004; 61(2): 339 - 351. [Abstract] [Full Text] [PDF] |
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M. Pynn, K. Schafer, S. Konstantinides, and M. Halle Exercise Training Reduces Neointimal Growth and Stabilizes Vascular Lesions Developing After Injury in Apolipoprotein E-Deficient Mice Circulation, January 27, 2004; 109(3): 386 - 392. [Abstract] [Full Text] [PDF] |
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E. Jeanpierre, T. Le Tourneau, I. Six, C. Zawadzki;, E. Van Belle, M. D. Ezekowitz, R. Bordet, S. Susen, B. Jude, and D. Corseaux Dietary Lipid Lowering Modifies Plaque Phenotype in Rabbit Atheroma After Angioplasty: A Potential Role of Tissue Factor Circulation, October 7, 2003; 108(14): 1740 - 1745. [Abstract] [Full Text] [PDF] |
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D Tousoulis, G Davies, C Stefanadis, P Toutouzas, and J A Ambrose Inflammatory and thrombotic mechanisms in coronary atherosclerosis Heart, September 1, 2003; 89(9): 993 - 997. [Abstract] [Full Text] [PDF] |
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F. Mulhaupt, C. M Matter, B. R Kwak, G. Pelli, N. R Veillard, F. Burger, P. Graber, T. F Luscher, and F. Mach Statins (HMG-CoA reductase inhibitors) reduce CD40 expression in human vascular cells Cardiovasc Res, September 1, 2003; 59(3): 755 - 766. [Abstract] [Full Text] [PDF] |
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A. J. Grau and C. Lichy Editorial Comment: Stroke and the CD40-CD40 Ligand System: At the Hinge Between Inflammation and Thrombosis Stroke, June 1, 2003; 34(6): 1417 - 1418. [Full Text] [PDF] |
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K. Takayama, G. Garcia-Cardena, G. K. Sukhova, J. Comander, M. A. Gimbrone Jr., and P. Libby Prostaglandin E2 Suppresses Chemokine Production in Human Macrophages through the EP4 Receptor J. Biol. Chem., November 8, 2002; 277(46): 44147 - 44154. [Abstract] [Full Text] [PDF] |
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A. C. Sposito and M. J. Chapman Statin Therapy in Acute Coronary Syndromes: Mechanistic Insight Into Clinical Benefit Arterioscler Thromb Vasc Biol, October 1, 2002; 22(10): 1524 - 1534. [Abstract] [Full Text] [PDF] |
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M. Aikawa, S. Sugiyama, C. C. Hill, S. J. Voglic, E. Rabkin, Y. Fukumoto, F. J. Schoen, J. L. Witztum, and P. Libby Lipid Lowering Reduces Oxidative Stress and Endothelial Cell Activation in Rabbit Atheroma Circulation, September 10, 2002; 106(11): 1390 - 1396. [Abstract] [Full Text] [PDF] |
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U. Bavendiek, P. Libby, M. Kilbride, R. Reynolds, N. Mackman, and U. Schonbeck Induction of Tissue Factor Expression in Human Endothelial Cells by CD40 Ligand Is Mediated via Activator Protein 1, Nuclear Factor kappa B, and Egr-1 J. Biol. Chem., July 5, 2002; 277(28): 25032 - 25039. [Abstract] [Full Text] [PDF] |
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R. Baetta, M. Camera, C. Comparato, C. Altana, M. D. Ezekowitz, and E. Tremoli Fluvastatin Reduces Tissue Factor Expression and Macrophage Accumulation in Carotid Lesions of Cholesterol-Fed Rabbits in the Absence of Lipid Lowering Arterioscler Thromb Vasc Biol, April 1, 2002; 22(4): 692 - 698. [Abstract] [Full Text] [PDF] |
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M. D. Rekhter How to evaluate plaque vulnerability in animal models of atherosclerosis? Cardiovasc Res, April 1, 2002; 54(1): 36 - 41. [Abstract] [Full Text] [PDF] |
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A. H.M Moons, M. Levi, and R. J.G Peters Tissue factor and coronary artery disease Cardiovasc Res, February 1, 2002; 53(2): 313 - 325. [Abstract] [Full Text] [PDF] |
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U. Schonbeck and P. Libby CD40 Signaling and Plaque Instability Circ. Res., December 7, 2001; 89(12): 1092 - 1103. [Abstract] [Full Text] [PDF] |
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M. T. Johnstone, R. M. Botnar, A. S. Perez, R. Stewart, W. C. Quist, J. A. Hamilton, and W. J. Manning In Vivo Magnetic Resonance Imaging of Experimental Thrombosis in a Rabbit Model Arterioscler Thromb Vasc Biol, September 1, 2001; 21(9): 1556 - 1560. [Abstract] [Full Text] [PDF] |
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P. Libby Current Concepts of the Pathogenesis of the Acute Coronary Syndromes Circulation, July 17, 2001; 104(3): 365 - 372. [Full Text] [PDF] |
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M. Aikawa and P. Libby Vascular inflammation and activation: new targets for lipid lowering Eur. Heart J. Suppl., May 1, 2001; 3(suppl_B): B3 - B11. [Abstract] [PDF] |
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Y. Fukumoto, P. Libby, E. Rabkin, C. C. Hill, M. Enomoto, Y. Hirouchi, M. Shiomi, and M. Aikawa Statins Alter Smooth Muscle Cell Accumulation and Collagen Content in Established Atheroma of Watanabe Heritable Hyperlipidemic Rabbits Circulation, February 20, 2001; 103(7): 993 - 999. [Abstract] [Full Text] [PDF] |
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M. Aikawa, E. Rabkin, S. Sugiyama, S. J. Voglic, Y. Fukumoto, Y. Furukawa, M. Shiomi, F. J. Schoen, and P. Libby An HMG-CoA Reductase Inhibitor, Cerivastatin, Suppresses Growth of Macrophages Expressing Matrix Metalloproteinases and Tissue Factor In Vivo and In Vitro Circulation, January 16, 2001; 103(2): 276 - 283. [Abstract] [Full Text] [PDF] |
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M. S. Penn, M.-Z. Cui, A. L. Winokur, J. Bethea, T. A. Hamilton, P. E. DiCorleto, and G. M. Chisolm Smooth muscle cell surface tissue factor pathway activation by oxidized low-density lipoprotein requires cellular lipid peroxidation Blood, November 1, 2000; 96(9): 3056 - 3063. [Abstract] [Full Text] [PDF] |
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M. M. Kockx, C. Seye, G. R. Y. De Meyer, M. W. M. Knaapen, M. Aikawa, S. J. Voglic, S. Sugiyama, E. Rabkin, P. Libby, M. B. Taubman, et al. Decreased Apoptosis and Tissue Factor Expression After Lipid Lowering Response Circulation, September 26, 2000; 102 (13): e99 - e99. [Full Text] [PDF] |
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S. Matetzky, S. Tani, S. Kangavari, P. Dimayuga, J. Yano, H. Xu, K.-Y. Chyu, M. C. Fishbein, P. K. Shah, and B. Cercek Smoking Increases Tissue Factor Expression in Atherosclerotic Plaques : Implications for Plaque Thrombogenicity Circulation, August 8, 2000; 102(6): 602 - 604. [Abstract] [Full Text] [PDF] |
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M. J Davies CORONARY DISEASE: The pathophysiology of acute coronary syndromes Heart, March 1, 2000; 83(3): 361 - 366. [Full Text] |
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R. Baetta, M. Camera, C. Comparato, C. Altana, M. D. Ezekowitz, and E. Tremoli Fluvastatin Reduces Tissue Factor Expression and Macrophage Accumulation in Carotid Lesions of Cholesterol-Fed Rabbits in the Absence of Lipid Lowering Arterioscler Thromb Vasc Biol, April 1, 2002; 22(4): 692 - 698. [Abstract] [Full Text] [PDF] |
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