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(Circulation. 1997;96:396-399.)
© 1997 American Heart Association, Inc.

Articles

Activation of Monocyte/Macrophage Functions Related to Acute Atheroma Complication by Ligation of CD40

Induction of Collagenase, Stromelysin, and Tissue Factor

François Mach, MD; Uwe Schönbeck, PhD; Jean-Yves Bonnefoy, PhD; Jordan S. Pober, MD, PhD; ; Peter Libby, MD

From the Vascular Medicine and Atherosclerosis Unit (F.M., U.S., P.L.), Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Mass; the Geneva Biomedical Research Institute (J.-Y.B.), Geneva, Switzerland; and the Molecular Cardiobiology Program, Boyer Center for Molecular Medicine (J.S.P), Yale University School of Medicine, New Haven, Conn.

Correspondence to Peter Libby, MD, Vascular Medicine and Atherosclerosis Unit, Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Ave, LMRC 307, Boston, MA 02115. E-mail plibby{at}bustoff.bwh.harvard.edu

	Abstract

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Background Plaque disruption with thrombosis commonly causes the acute coronary syndromes. Macrophages, abundant at sites of plaque rupture, release proteinases that weaken plaques and express tissue factor (TF), which initiates thrombosis. The signals that induce expression of these macrophage functions, particularly TF, remain obscure. Recent studies have localized the receptor CD40 and its ligand in human atheroma. This study tested the hypothesis that ligation of CD40 can activate key mononuclear phagocyte functions related to clinical manifestations of atheroma.

Methods and Results Stimulation of human monocytes/macrophages through CD40 by either membranes from activated T cells or recombinant CD40L (rCD40L) induced expression of interstitial collagenase, stromelysin, and TF protein and activity. In contrast, the soluble cytokines interleukin-1 or tumor necrosis factor- did not induce or weakly induced TF expression. Neutralization with anti-CD40L antibody markedly inhibited these actions of both T-cell membranes and rCD40L.

Conclusions By inducing the expression of matrix-degrading proteinases and of TF procoagulant, CD40 signaling may contribute to the triggering of acute coronary events.

Key Words: CD40 ligands • atheroma • thrombosis • plaque • macrophages

	Introduction

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Acute coronary events commonly result from thrombosis triggered by disruption of an atherosclerotic plaque.^{1 2 3} Activated macrophages abound at sites of plaque rupture^{4 5} and express TF, a potent procoagulant.^{6 7 8} Physical disruption of the plaque promoted by macrophage-derived proteinases permits access of blood coagulation proteins to TF in the lipid-rich core. Macrophages can produce proteinases capable of digesting the collagen and elastin of the plaque.⁹ The signals that elicit expression of these maladaptive macrophage functions, TF and matrix-degrading proteinases, remain incompletely elucidated. In addition to macrophages, T cells localize in regions of plaque rupture.¹⁰ Soluble mediators such as cytokines elaborated by macrophages, T cells, and vascular wall cells can induce gelatinases in macrophages.¹¹ However, the signals that elicit expression of interstitial collagenase (MMP-1) and stromelysin (MMP-3), enzymes crucial for initiating the breakdown of the major structural component of the plaque fibrous cap, remain uncertain. Contact with activated T cells can induce TF expression by macrophages in vitro¹² by a hitherto unknown mechanism.

Activated T cells can express on their surface CD40L, a TNF-like molecule.¹³ Vascular cells and macrophages can express functional CD40L as well as its receptor CD40 in vitro and in atherosclerotic plaques in humans.¹⁴ This study tested the hypothesis that CD40 ligation on monocytes/macrophages elicits MMP and TF expression and may therefore contribute to weakening and thrombogenicity of the atherosclerotic plaque, mechanisms underlying the onset of acute coronary syndromes.

	Methods

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Reagents
rTF, mouse monoclonal anti-human TF antibodies, human recombinant factor VIIa, human factor X, and Spectrozyme fXa were purchased from American Diagnostica. Human rCD40L was obtained from Geneva Biomedical Research Institute.¹⁵ IFN- was purchased from Endogen. Rabbit polyclonal anti-human MMP-1 and MMP-3 antibodies were provided by Pfizer. Anti-human CD40L mAb were from Calbiochem or Genzyme.

Cell Isolation and T-Cell Membrane Preparation
Mononuclear phagocytes were isolated by adherence to uncoated plastic culture flasks (2 hours, 37°C) from human PBMC (provided by S.K. Clinton, Dana Farber Institute) freshly prepared by density gradient centrifugation.¹⁴ Adherent PBMC were harvested by scraping and were resuspended in RPMI 1640 medium containing 10% human serum (Sigma) and used for experiments. The purity of mononuclear phagocytes was 98% as determined by FACS (anti-CD64 mAb, PharMingen). This study refers to cultures of these cells as monocytes/macrophages. Human CD4+ T cells were isolated from freshly prepared PBMC by CD4+ positive selection (a gift from Dr Andrew Lichtman, Brigham and Women's Hospital, Boston, Mass) as described.¹⁶ The purity was 98% (FACS analysis with anti-CD4 mAb, Calbiochem). CD4+ T cells were activated with PMA (50 ng/mL, 18 hours), and CD40L cell surface expression was confirmed by FACS analysis with anti-CD40L mAb. Cell membranes were prepared¹⁷ and resuspended in RPMI medium (BioWhittaker) containing 500 ng/mL polymyxin B and stored at -70°C. Culture media and FCS contained <40 pg LPS/mL as determined by the chromogenic Limulus amoebocyte assay.

Western Blotting
Concentrated supernatants (10x) were separated by SDS-PAGE and blotted onto polyvinylidene difluoride membranes (Bio-Rad) with the use of a semidry blotting apparatus. Blocking of nonspecific binding and dilutions of the primary (1:10 000 anti-MMP-1, 1:2000 anti-MMP-3) and secondary (1:20 000, Jackson Immunoresearch) antibodies used 5% defatted dry milk/PBS/0.1% Tween 20. Proteins were visualized by addition of diaminobenzidine (1 mg/mL, Sigma) in substrate buffer (17 mmol/L acetic acid/65 mmol/L Na₂HPO₄/0.01% thimerosal/0.1% H₂O₂).

Tissue Factor Activity Assay
TF activity was determined chromogenically.¹⁸ Monocyte/macrophage lysates (50 µL, 3x10⁶ cells/mL) in 50 mmol/L Tris, 100 mmol/L NaCl, 1% bovine serum albumin, pH 7.4, were incubated in triplicate at 37°C in a 96-well plate (Nunc) with or without anti-TF antibody (1:100, 30 minutes). Human factor VIIa, factor X, and the chromogenic substrate (Spectrozyme fXa) were added as recommended, and optical density was monitored at 410 nm. rTF was used in calibration.

Flow Cytometry
Human monocytes/macrophages (>30 000 viable cells/conditions) were incubated with the FITC-conjugated anti-human TF antibody (30 minutes, 4°C) and analyzed by FACS (Becton Dickinson).

	Results

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Activation of Human Monocytes/Macrophages Through CD40 Induces Collagenase and Stromelysin Expression
Unstimulated monocytes/macrophages did not express MMP-1 or MMP-3. Activation of monocytes/macrophages with membranes of PMA-stimulated (50 ng/mL, 18 hours) CD4+ T cells induced MMP-1 and MMP-3 expression (Fig 1, left). Anti-CD40L mAb limited this effect. rCD40L mimicked the effect of cell membranes from activated CD4+ T cells. IFN- inhibited induction of MMPs by rCD40L. Release of MMP-1 and MMP-3 by monocytes/macrophages increased with time (Fig 1, right) and rCD40L concentration (data not shown).

View larger version (28K): [in this window] [in a new window]   Figure 1. Concentrated cultured media were analyzed by Western blotting for MMP-1 and MMP-3. Left, Human monocytes/macrophages cultured in serum-free medium were incubated (24 hours) with rCD40L (5 µg/mL) or cell membranes isolated from activated CD4+ T cells in the presence or absence of an anti-CD40L mAb (-CD40L, 1 µg/mL) or with rCD40L and IFN- (1000 U/mL). As control, monocytes/macrophages without stimulation (None) are shown. Right, Monocytes/macrophages cultured in serum-free medium were incubated with rCD40L (5 µg/mL) for the indicated time.

Ligation of CD40 on Human Monocytes/Macrophages Induces Expression and Activity of Tissue Factor
Ligation of CD40 on monocytes/macrophages induced TF cell surface expression, whereas unstimulated monocytes/macrophages expressed little or no TF (Fig 2). FACS analysis monitored the surface expression of TF on monocytes/macrophages exposed to either cell membranes isolated from activated CD4+ T cells or rCD40 L (Fig 2, A and B). Addition of an anti-CD40L mAb blocked induction of TF in response to CD40 ligation. Stimulation of monocytes/macrophages with rCD40L and IFN- slightly increased the expression of TF (data not shown), whereas IL-1 or TNF- did not induce or weakly induced TF in monocytes/macrophages (data not shown), consistent with previous reports.⁸

View larger version (18K): [in this window] [in a new window]   Figure 2. FACS analysis of monocytes/macrophages cultured in RPMI medium supplemented with 10% human serum stained for TF (open histograms) or the isotype control (solid histograms). A, Monocytes/macrophages stimulated (12 hours) with cell membranes isolated from activated CD4+ T cells in the presence or absence of an anti-CD40L mAb (-CD40L, 1 µg/mL). B, Monocytes/macrophages were stimulated (12 hours) with rCD40L (5 µg/mL) in the presence or absence of an anti-CD40L mAb (-CD40L, 1 µg/mL). C, Monocytes/macrophages were stimulated with rCD40L (5 µg/mL) for the indicated time.

Stimulation of monocytes/macrophages with either cell membranes isolated from activated CD4+ T cells or with rCD40L induced TF enzymatic activity (Table). Anti-human TF antibody blocked TF activity by both of these stimuli, as did addition of an anti-CD40L mAb. Monocytes/macrophages stimulated with rCD40L and IFN- showed slightly increased procoagulant activity. TF activity increased with time (Table) and rCD40L concentration (data not shown).

View this table: [in this window] [in a new window]   Table 1. Ligation of CD40 on Monocytes/Macrophages Induces Tissue Factor Activity

	Discussion

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Functional attributes rather than size alone determine the propensity of atherosclerotic plaques to provoke acute clinical syndromes. Much evidence supports the role of TF in inciting the thrombosis that causes most acute coronary syndromes.¹⁹ Macrophage content and expression of TF correlate with rupture and instability of the atherosclerotic plaque.^{6 7 19} Macrophage-derived MMPs can digest the plaque extracellular matrix and thus impair its stability.⁹ Plaque rupture exposes circulating blood components to the TF-rich lipid core, inciting thrombosis.

Understanding the fundamental mechanism of atheroma destabilization requires definition of the signals that elicit overexpression of MMPs and TF. We and others have invoked cytokines, protein mediators of inflammation, as instigators of such functions. Yet, soluble cytokines such as IL-1 and TNF- cannot explain all of the features of activated mononuclear phagocytes associated with unstable coronary syndromes, particularly TF production. Although IL-1 and TNF- can elicit gelatinase production by macrophages, knowledge of the stimuli for overexpression of interstitial collagenase and stromelysin in plaques remains incomplete. T cells induce macrophage TF production by a hitherto unknown contact-dependent mechanism.^{8 12}

Since we recently found that cells within the human atheroma express CD40 and CD40L,¹⁴ this study investigated the potential roles of CD40-CD40L signaling in processes putatively involved in plaque rupture. We found that CD40 ligation on monocytes/macrophages by either cell membranes isolated from activated CD4+ T cells or rCD40L induces the proteinases collagenase (MMP-1) and stromelysin (MMP-3) as well as TF expression and activity. The present results provide a likely candidate for the elusive contact-dependent T-cell activator of TF expression by mononuclear phagocytes.¹²

This study suggests a novel mechanism for activation by T lymphocytes of macrophage functions related to clinical instability of atheroma: CD40-CD40L signaling may induce digestion of the extracellular matrix components such as collagen and elastin and promote a procoagulant state within the lesion, features that favor, respectively, the development of plaque rupture and thrombosis. IFN-, a cytokine released by activated T cells, suppressed the rCD40L-induced MMP but not TF expression. The concentration of inhibitory (eg, IFN-) as well as stimulatory (eg, IL-1 or TNF-) soluble mediators in the plaque may determine whether the direct cell contact between macrophages and activated CD4+ T lymphocytes results in expression and release of matrix-degrading enzymes. Smooth muscle cells and macrophages within the human atherosclerotic lesion, in addition to activated T cells, express CD40L. In vivo, stimulation of MMP production by CD40L from multiple cell types may outweigh inhibition by IFN-, elaborated only by T cells, as indicated by the overexpression of MMP and proteolytic activity in lesional macrophages.⁹ The present data point to the CD40 signaling system as a crucial regulator of macrophage functions directly related to the propensity of plaques to cause acute clinical manifestations. Interruption of CD40 signaling, by blocking proximally both proteolytic and procoagulant pathways, could provide a novel means of atheroma stabilization.

	Selected Abbreviations and Acronyms

 

CD40L = CD40 ligand FACS = fluorescence-activated cell sorter FITC = fluorescein isothiocyanate IFN = interferon IL = interleukin mAb = monoclonal antibody(ies) MMP = matrix metalloproteinase PBMC = peripheral blood mononuclear cells RPMI = Roswell Park Memorial Institute (medium) TF = tissue factor TNF = tumor necrosis factor

	Acknowledgments

 
This work was supported in part by grants from the National Heart, Lung, and Blood Institute to Dr Libby and Dr Pober (HL-43364), from the Swiss National Research Fund to Dr Mach, and from the Deutsche Forschungsgemeinschaft to Dr Schönbeck (Scho 614/1-1). We thank Maria Muszynski and Elissa Simon-Morrissey (Brigham and Women's Hospital) for their skillful technical assistance and Clive Long of Pfizer Central Research, Kent, UK, for the gift of anti-MMP antibodies.

	Footnotes

 
F.M. and U.S. contributed equally to this work.

Received March 31, 1997; revision received May 6, 1997; accepted May 30, 1997.

	References

Top Abstract Introduction Methods Results Discussion References

 
1. Fuster V, Lewis A. Conner Memorial Lecture. Mechanisms leading to myocardial infarction: insights from studies of vascular biology. Circulation. 1994;90:2126-2146.[Abstract/Free Full Text]

2. Moreno PR, Shah PK, Falk E. Determination of rupture of atherosclerotic coronary lesions. In: Willich SN, Muller JE, eds. Triggering of Acute Coronary Syndromes: Implications for Prevention. Dordrecht, Netherlands: Kluwer Academic Publishers; 1996:268-283.

3. Van der Wal AC, Becker AE, van der Loos CM, Das PK. Site of intimal rupture or erosion of thrombosed coronary atherosclerotic plaques is characterized by an inflammatory process irrespective to the dominant plaque morphology. Circulation. 1994;89:36-44.[Abstract/Free Full Text]

4. Libby P. Molecular bases of acute coronary syndromes. Circulation. 1995;91:2844-2850.[Free Full Text]

5. Moreno PR, Falk E, Palacios IF, Newell JB, Fuster V, Fallon JT. Monocyte infiltration in acute coronary syndromes: implications for plaque rupture. Circulation. 1994;90:775-778.[Abstract/Free Full Text]

6. Wilcox JN, Smith KM, Schwartz SM, Gordon D. Localization of tissue factor in the normal vessel wall and in the atherosclerotic plaque. Proc Natl Acad Sci U S A. 1989;86:2839-2842.[Abstract/Free Full Text]

7. Moreno PR, Bernardi VH, Lopez-Cuellar J, Murcia AM, Palacios IF, Gold HK, Mehran R, Sharma SK, Nemerson Y, Fuster V, Fallon JT. Macrophages, smooth muscle cells and tissue factor in unstable angina: implications for cell-mediated thrombogenicity in acute coronary syndromes. Circulation. 1996;94:3090-3097.[Abstract/Free Full Text]

8. Camerer E, Kolstø AB, Pryde H. Cell biology of tissue factor, the principal initiator of blood coagulation. Thromb Res. 1996;81:1-41.

9. Galis ZS, Sukhova GK, Lark MW, Libby P. Increased expression of matrix metalloproteinases and matrix degrading activity in vulnerable regions of human atherosclerotic plaques. J Clin Invest. 1994;94:2493-2503.

10. Zhou X, Stemme S, Hansson GK. Evidence for a local immune response in atherosclerosis. Am J Pathol. 1996;149:359-366.[Abstract]

11. Saren P, Welgus HG, Kovanen PT. TNF- and IL-1ß selectively induce expression of 92-kDa gelatinase by human macrophages. J Immunol. 1996;157:4159-4165.[Abstract]

12. Gregory SA, Edgington TS. Tissue factor induction in human monocytes: two distinct mechanisms displayed by different alloantigen responsive T cell clones. J Clin Invest. 1985;76:2440-2445.

13. Foy TM, Aruffo A, Bajorath J, Buhlmann JE, Noelle RJ. Immune regulation by CD40 and its ligand gp39. Annu Rev Immunol. 1996;14:591-617.[Medline] [Order article via Infotrieve]

14. Mach F, Schönbeck U, Sukhova GK, Bourcier T, Bonnefoy JY, Pober JS, Libby P. Functional CD40 ligand is expressed on human vascular endothelial cells, smooth muscle cells, and macrophages: implications for CD40-CD40 ligand signaling in atherosclerosis. Proc Natl Acad Sci U S A. 1997;94:1931-1936.[Abstract/Free Full Text]

15. Mazzei GJ, Edgerton MD, Losberger C, Lecoanet-Henchoz S, Graber P, Durandy A, Gauchat JF, Bernard A, Allet B, Bonnefoy JY. Human native soluble CD40 L is a biologically active trimer, processed inside microsomes. J Biol Chem. 1995;270:7025-7028.[Abstract/Free Full Text]

16. Luscinskas FW, Ding Han, Lichtman AH. P-selectin and vascular cell adhesion molecule 1 mediate rolling and arrest, respectively, of CD4+ T lymphocytes on tumor necrosis factor a-activated vascular endothelium under flow. J Exp Med. 1997;181:1179-1186.[Abstract/Free Full Text]

17. Malik N, Greenfield BW, Wahl AF, Kiener PA. Activation of human monocytes through CD40L induces matrix metalloproteinases. J Immunol. 1996;156:3952-3960.[Abstract]

18. Carson SD. Continuous chromogenic tissue factor assay: comparison to clot-based assays and sensitivity established using pure tissue factor. Thromb Res. 1987;47:379-387.[Medline] [Order article via Infotrieve]

19. Annex BH, Denning SM, Keith MC, Sketch MH, Stack RS, Morissey JH, Peters KG. Differential expression of tissue factor protein in directional atherectomy specimens from patients with stable and unstable coronary syndromes. Circulation. 1995;91:619-622.[Abstract/Free Full Text]

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				C. Monaco, E. Andreakos, S. Young, M. Feldmann, and E. Paleolog T cell-mediated signaling to vascular endothelium: induction of cytokines, chemokines, and tissue factor J. Leukoc. Biol., April 1, 2002; 71(4): 659 - 668. [Abstract] [Full Text] [PDF]

				J. Kim and R. A. Feldman Activated Fes Protein Tyrosine Kinase Induces Terminal Macrophage Differentiation of Myeloid Progenitors (U937 Cells) and Activation of the Transcription Factor PU.1 Mol. Cell. Biol., March 15, 2002; 22(6): 1903 - 1918. [Abstract] [Full Text] [PDF]

				Z. S. Galis and J. J. Khatri Matrix Metalloproteinases in Vascular Remodeling and Atherogenesis: The Good, the Bad, and the Ugly Circ. Res., February 22, 2002; 90(3): 251 - 262. [Abstract] [Full Text] [PDF]

				T. Nakajima, S. Schulte, K. J. Warrington, S. L. Kopecky, R. L. Frye, J. J. Goronzy, and C. M. Weyand T-Cell-Mediated Lysis of Endothelial Cells in Acute Coronary Syndromes Circulation, February 5, 2002; 105(5): 570 - 575. [Abstract] [Full Text] [PDF]

				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]

				U. Schonbeck and P. Libby CD40 Signaling and Plaque Instability Circ. Res., December 7, 2001; 89(12): 1092 - 1103. [Abstract] [Full Text] [PDF]

				C D Garlichs, S Eskafi, D Raaz, A Schmidt, J Ludwig, M Herrmann, L Klinghammer, W G Daniel, and A Schmeisser Patients with acute coronary syndromes express enhanced CD40 ligand/CD154 on platelets Heart, December 1, 2001; 86(6): 649 - 655. [Abstract] [Full Text] [PDF]

				A. Bobik and N. Kalinina Tumor Necrosis Factor Receptor and Ligand Superfamily Family Members TNFRSF14 and LIGHT: New Players in Human Atherogenesis Arterioscler. Thromb. Vasc. Biol., December 1, 2001; 21(12): 1873 - 1875. [Full Text] [PDF]

				G. K. Hansson Immune Mechanisms in Atherosclerosis Arterioscler. Thromb. Vasc. Biol., December 1, 2001; 21(12): 1876 - 1890. [Abstract] [Full Text] [PDF]

				G. J. Blake and P. M. Ridker Novel Clinical Markers of Vascular Wall Inflammation Circ. Res., October 26, 2001; 89(9): 763 - 771. [Abstract] [Full Text] [PDF]

				P. K. Shah and Z. S. Galis Matrix Metalloproteinase Hypothesis of Plaque Rupture: Players Keep Piling Up But Questions Remain Circulation, October 16, 2001; 104(16): 1878 - 1880. [Full Text] [PDF]

				P. Libby and U. Schonbeck Drilling for Oxygen: Angiogenesis Involves Proteolysis of the Extracellular Matrix Circ. Res., August 3, 2001; 89(3): 195 - 197. [Full Text] [PDF]

				M. A. Houtkamp, A. C. van der Wal, O. J. de Boer, C. M. van der Loos, P. A. J. de Boer, A. F. M. Moorman, and A. E. Becker Interleukin-15 Expression in Atherosclerotic Plaques : An Alternative Pathway for T-Cell Activation in Atherosclerosis? Arterioscler. Thromb. Vasc. Biol., July 1, 2001; 21(7): 1208 - 1213. [Abstract] [Full Text] [PDF]

				T. Kislinger, N. Tanji, T. Wendt, W. Qu, Y. Lu, L. J. Ferran Jr, A. Taguchi, K. Olson, L. Bucciarelli, M. Goova, et al. Receptor for Advanced Glycation End Products Mediates Inflammation and Enhanced Expression of Tissue Factor in Vasculature of Diabetic Apolipoprotein E-Null Mice Arterioscler. Thromb. Vasc. Biol., June 1, 2001; 21(6): 905 - 910. [Abstract] [Full Text] [PDF]

				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]

				P. Libby and D. I. Simon Inflammation and Thrombosis : The Clot Thickens Circulation, April 3, 2001; 103(13): 1718 - 1720. [Full Text] [PDF]

				S. Jander, M. Sitzer, A. Wendt, M. Schroeter, M. Buchkremer, M. Siebler, W. Muller, W. Sandmann, and G. Stoll Expression of Tissue Factor in High-Grade Carotid Artery Stenosis : Association With Plaque Destabilization Stroke, April 1, 2001; 32(4): 850 - 854. [Abstract] [Full Text] [PDF]

				G. Liuzzo, A. N. Vallejo, S. L. Kopecky, R. L. Frye, D. R. Holmes, J. J. Goronzy, and C. M. Weyand Molecular Fingerprint of Interferon-{{gamma}} Signaling in Unstable Angina Circulation, March 20, 2001; 103(11): 1509 - 1514. [Abstract] [Full Text] [PDF]

				M. Remskar, H. Li, K.-Y. Chyu, P. K. Shah, and B. Cercek Absence of CD40 Signaling Is Associated With an Increase in Intimal Thickening After Arterial Injury Circ. Res., March 2, 2001; 88(4): 390 - 394. [Abstract] [Full Text] [PDF]

				D M Braganza and M R Bennett New insights into atherosclerotic plaque rupture Postgrad. Med. J., February 1, 2001; 77(904): 94 - 98. [Full Text]

				N. Marx, N. Mackman, U. Schonbeck, N. Yilmaz, V. Hombach, P. Libby, and J. Plutzky PPAR{{alpha}} Activators Inhibit Tissue Factor Expression and Activity in Human Monocytes Circulation, January 16, 2001; 103(2): 213 - 219. [Abstract] [Full Text] [PDF]

				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]

				R. Rauramaa, S. B. Vaisanen, L.-A. Luong, A. Schmidt-Trucksass, I. M. Penttila, C. Bouchard, J. Toyry, and S. E. Humphries Stromelysin-1 and Interleukin-6 Gene Promoter Polymorphisms Are Determinants of Asymptomatic Carotid Artery Atherosclerosis Arterioscler. Thromb. Vasc. Biol., December 1, 2000; 20(12): 2657 - 2662. [Abstract] [Full Text] [PDF]

				J. M. Waugh, J. Li-Hawkins, E. Yuksel, M. D. Kuo, P. N. Cifra, P. R. Hilfiker, R. Geske, M. Chawla, J. Thomas, S. M. Shenaq, et al. Thrombomodulin Overexpression to Limit Neointima Formation Circulation, July 18, 2000; 102(3): 332 - 337. [Abstract] [Full Text] [PDF]

				U. Schonbeck, G. K. Sukhova, K. Shimizu, F. Mach, and P. Libby Inhibition of CD40 signaling limits evolution of established atherosclerosis in mice PNAS, June 20, 2000; 97(13): 7458 - 7463. [Abstract] [Full Text] [PDF]

				E. Lutgens, K. B. J. M. Cleutjens, S. Heeneman, V. E. Koteliansky, L. C. Burkly, and M. J. A. P. Daemen Both early and delayed anti-CD40L antibody treatment induces a stable plaque phenotype PNAS, June 20, 2000; 97(13): 7464 - 7469. [Abstract] [Full Text] [PDF]

				C. Chizzolini, R. Rezzonico, C. De Luca, D. Burger, and J.-M. Dayer Th2 Cell Membrane Factors in Association with IL-4 Enhance Matrix Metalloproteinase-1 (MMP-1) While Decreasing MMP-9 Production by Granulocyte-Macrophage Colony-Stimulating Factor-Differentiated Human Monocytes J. Immunol., June 1, 2000; 164(11): 5952 - 5960. [Abstract] [Full Text] [PDF]

				J. Golledge, R. M. Greenhalgh, and A. H. Davies The Symptomatic Carotid Plaque Stroke, March 1, 2000; 31(3): 774 - 781. [Abstract] [Full Text] [PDF]

				U. Schonbeck, F. Mach, G. K. Sukhova, M. Herman, P. Graber, M. R. Kehry, and P. Libby CD40 Ligation Induces Tissue Factor Expression in Human Vascular Smooth Muscle Cells Am. J. Pathol., January 1, 2000; 156(1): 7 - 14. [Abstract] [Full Text] [PDF]

				L. J. Pinderski Oslund, C. C. Hedrick, T. Olvera, A. Hagenbaugh, M. Territo, J. A. Berliner, and A. I. Fyfe Interleukin-10 Blocks Atherosclerotic Events In Vitro and In Vivo Arterioscler. Thromb. Vasc. Biol., December 1, 1999; 19(12): 2847 - 2853. [Abstract] [Full Text] [PDF]

				U. Schonbeck, G. K. Sukhova, P. Graber, S. Coulter, and P. Libby Augmented Expression of Cyclooxygenase-2 in Human Atherosclerotic Lesions Am. J. Pathol., October 1, 1999; 155(4): 1281 - 1291. [Abstract] [Full Text] [PDF]

				M. Aikawa, S. J. Voglic, S. Sugiyama, E. Rabkin, M. B. Taubman, J. T. Fallon, and P. Libby Dietary Lipid Lowering Reduces Tissue Factor Expression in Rabbit Atheroma Circulation, September 14, 1999; 100(11): 1215 - 1222. [Abstract] [Full Text] [PDF]

				P. Aukrust, F. Muller, T. Ueland, T. Berget, E. Aaser, A. Brunsvig, N. O. Solum, K. Forfang, S. S. Froland, and L. Gullestad Enhanced Levels of Soluble and Membrane-Bound CD40 Ligand in Patients With Unstable Angina : Possible Reflection of T Lymphocyte and Platelet Involvement in the Pathogenesis of Acute Coronary Syndromes Circulation, August 10, 1999; 100(6): 614 - 620. [Abstract] [Full Text] [PDF]

				S. E. Epstein, Y. F. Zhou, and J. Zhu Infection and Atherosclerosis : Emerging Mechanistic Paradigms Circulation, July 27, 1999; 100 (4): e20 - e28. [Abstract] [Full Text] [PDF]

				B. C. Biedermann and J. S. Pober Human Vascular Endothelial Cells Favor Clonal Expansion of Unusual Alloreactive CTL J. Immunol., June 15, 1999; 162(12): 7022 - 7030. [Abstract] [Full Text] [PDF]

				G. K. Sukhova, U. Schonbeck, E. Rabkin, F. J. Schoen, A. R. Poole, R. C. Billinghurst, and P. Libby Evidence for Increased Collagenolysis by Interstitial Collagenases-1 and -3 in Vulnerable Human Atheromatous Plaques Circulation, May 18, 1999; 99(19): 2503 - 2509. [Abstract] [Full Text] [PDF]

				U. Schonbeck, F. Mach, G. K. Sukhova, E. Atkinson, E. Levesque, M. Herman, P. Graber, P. Basset, and P. Libby Expression of Stromelysin-3 in Atherosclerotic Lesions: Regulation via CD40-CD40 Ligand Signaling In Vitro and In Vivo J. Exp. Med., March 1, 1999; 189(5): 843 - 853. [Abstract] [Full Text] [PDF]

				R. Rabbani and E. J. Topol Strategies to achieve coronary arterial plaque stabilization Cardiovasc Res, February 1, 1999; 41(2): 402 - 417. [Abstract] [Full Text] [PDF]

				R. Ross Atherosclerosis -- An Inflammatory Disease N. Engl. J. Med., January 14, 1999; 340(2): 115 - 126. [Full Text] [PDF]

				F. Mach, U. Schonbeck, R. P. Fabunmi, C. Murphy, E. Atkinson, J.-Y. Bonnefoy, P. Graber, and P. Libby T Lymphocytes Induce Endothelial Cell Matrix Metalloproteinase Expression by a CD40L-Dependent Mechanism : Implications for Tubule Formation Am. J. Pathol., January 1, 1999; 154(1): 229 - 238. [Abstract] [Full Text] [PDF]

				P. Libby The interface of atherosclerosis and thrombosis: basic mechanisms Vascular Medicine, August 1, 1998; 3(3): 225 - 229. [Abstract] [PDF]

				M. Aikawa, E. Rabkin, Y. Okada, S. J. Voglic, S. K. Clinton, C. E. Brinckerhoff, G. K. Sukhova, and P. Libby Lipid Lowering by Diet Reduces Matrix Metalloproteinase Activity and Increases Collagen Content of Rabbit Atheroma : A Potential Mechanism of Lesion Stabilization Circulation, June 23, 1998; 97(24): 2433 - 2444. [Abstract] [Full Text] [PDF]

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