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Härdtner C, Kumar A, Ehlert CA, Vico TA, Starz C, von Ehr A, Krebs K, Dufner B, Hoppe N, Stachon P, Heidt T, Wolf D, von Zur Mühlen C, Grüning B, Robbins CS, Maegdefessel L, Westermann D, Dederichs TS, Hilgendorf I. A comparative gene expression matrix in Apoe-deficient mice identifies unique and atherosclerotic disease stage-specific gene regulation patterns in monocytes and macrophages. Atherosclerosis 2023; 371:1-13. [PMID: 36940535 DOI: 10.1016/j.atherosclerosis.2023.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 03/02/2023] [Accepted: 03/08/2023] [Indexed: 03/23/2023]
Abstract
BACKGROUND AND AIMS Atherosclerosis is a systemic and chronic inflammatory disease propagated by monocytes and macrophages. Yet, our knowledge on how transcriptome of these cells evolves in time and space is limited. We aimed at characterizing gene expression changes in site-specific macrophages and in circulating monocytes during the course of atherosclerosis. METHODS We utilized apolipoprotein E-deficient mice undergoing one- and six-month high cholesterol diet to model early and advanced atherosclerosis. Aortic macrophages, peritoneal macrophages, and circulating monocytes from each mouse were subjected to bulk RNA-sequencing (RNA-seq). We constructed a comparative directory that profiles lesion- and disease stage-specific transcriptomic regulation of the three cell types in atherosclerosis. Lastly, the regulation of one gene, Gpnmb, whose expression positively correlated with atheroma growth, was validated using single-cell RNA-seq (scRNA-seq) of atheroma plaque from murine and human. RESULTS The convergence of gene regulation between the three investigated cell types was surprisingly low. Overall 3245 differentially expressed genes were involved in the biological modulation of aortic macrophages, among which less than 1% were commonly regulated by the remote monocytes/macrophages. Aortic macrophages regulated gene expression most actively during atheroma initiation. Through complementary interrogation of murine and human scRNA-seq datasets, we showcased the practicality of our directory, using the selected gene, Gpnmb, whose expression in aortic macrophages, and a subset of foamy macrophages in particular, strongly correlated with disease advancement during atherosclerosis initiation and progression. CONCLUSIONS Our study provides a unique toolset to explore gene regulation of macrophage-related biological processes in and outside the atheromatous plaque at early and advanced disease stages.
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Affiliation(s)
- Carmen Härdtner
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Anup Kumar
- Department of Computer Science, Bioinformatics Group, University of Freiburg, Georges-Koehler-Allee 106, Freiburg, Germany
| | - Carolin A Ehlert
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Tamara Antonela Vico
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Christopher Starz
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Alexander von Ehr
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Katja Krebs
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Bianca Dufner
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Natalie Hoppe
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Peter Stachon
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Timo Heidt
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Dennis Wolf
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Constantin von Zur Mühlen
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Björn Grüning
- Department of Computer Science, Bioinformatics Group, University of Freiburg, Georges-Koehler-Allee 106, Freiburg, Germany
| | - Clinton S Robbins
- Peter Munk Cardiac Centre, University Health Network, 101 College St, Toronto, Canada
| | - Lars Maegdefessel
- Department for Vascular and Endovascular Surgery, Technical University Munich, Arcisstr. 21, Munich, Germany; Deutsches Zentrum für Herz-Kreislaufforschung (DZHK), Berlin, Germany; Department of Medicine, Karolinska Institutet and University Hospital, Eugeniavägen 3, Stockholm, Sweden; Partner Site Munich Heart Alliance, Arcisstr. 21, Munich, Germany
| | - Dirk Westermann
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany
| | - Tsai-Sang Dederichs
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany.
| | - Ingo Hilgendorf
- Department of Cardiology and Angiology, University Heart Center Freiburg-Bad Krozingen, Faculty of Medicine, University of Freiburg, Hugstetter Street 55, Freiburg, Germany; Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen and Faculty of Medicine, University of Freiburg, Elsaesser Street 2Q, Freiburg, Germany.
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Figueiredo E, Miranda C. Is the variation in monocyte to high-density lipoprotein cholesterol ratio a predictor of major cardiovascular events after acute coronary syndrome? Braz J Med Biol Res 2023; 55:e12410. [PMID: 36629527 PMCID: PMC9828865 DOI: 10.1590/1414-431x2022e12410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 11/04/2022] [Indexed: 01/11/2023] Open
Abstract
In clinical practice, we need to develop new tools to identify the residual cardiovascular risk after acute coronary syndrome (ACS). This study aimed to evaluate whether the monocyte to high-density lipoprotein cholesterol ratio (MHR) variation (ΔMHR) obtained during hospital admission (MHR1) and repeated in the first outpatient evaluation (MHR2) is a predictor of major adverse cardiovascular events (MACE) after ACS. One hundred ninety-one patients admitted for ACS were prospectively included. The ΔMHR was calculated by subtracting MHR1 from MHR2. Patients were followed for 166±38 days in which the occurrence of MACE was observed. The best cutoff for ΔMHR was zero (0), and individuals were divided into two groups: ΔMHR<0 (n=113) and ΔMHR≥0 (n=78). The presence of MACE was higher in the ΔMHR≥0 (22%) than in the ΔMHR<0 (7%), with a hazard ratio (HR) of 3.96 (95% confidence interval [CI]: 1.74-8.99; P=0.0004). After adjusting for confounders, ΔMHR≥0 remained an independent MACE predictor with an adjusted HR of 3.13 (95%CI: 1.35-7.26, P=0.008). In conclusion, our study showed that ΔMHR was an independent MACE predictor after ACS. Thus, ΔMHR is a potential marker of residual cardiovascular risk after ACS.
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Affiliation(s)
- E.T. Figueiredo
- Divisão de Medicina de Emergência, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
| | - C.H. Miranda
- Divisão de Medicina de Emergência, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brasil
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Abstract
The 9p21.3 locus was the first to yield to genome-wide association studies (GWAS) seeking common genetic variants predisposing to increased risk of coronary artery atherosclerotic disease (CAD). The 59 single nucleotide polymorphisms that show highest association with CAD are clustered in a region 100,000 to 150,000 base pairs 5' to the cyclin-dependent kinase inhibitors CDKN2B (coding for p15(ink4b)) and CDKN2A (coding for p16(ink4a) and p14(ARF)). This region also covers the 3' end of a long noncoding RNA transcribed antisense to CDKN2B (CDKN2BAS, aka ANRIL for antisense noncoding RNA at the ink4 locus) whose expression has been linked to chromatin remodeling at the locus. Despite intensive investigation over the past 7 years, the functional significance of the 9p21.3 locus remains elusive. Other variants at this locus have been associated with glaucoma, glioma, and type 2 diabetes mellitus, diseases that implicate tissue-resident macrophages. Here, we review the evidence that genetic variants at 9p21.3 disrupt tissue-specific enhancers and propose new insights to guide future studies.
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Zhao ZW, Abendroth DK, Zhou ZC, Liu YZ, Pan FM, Ge JJ. Anti-inflammatory and anti-proliferative effects of CBS3830 in arterialized vein grafts in rats. Immunopharmacol Immunotoxicol 2014; 36:397-403. [PMID: 25204222 DOI: 10.3109/08923973.2014.956754] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To investigated whether CBS3830, a highly selectively inhibitor of p38MAPK, could ameliorate inflammation and intimal hyperplasia in arterialized vein grafts (AVGs). METHODS Sixty male Sprague-Dawley rats underwent a reversed right jugular vein to common carotid artery interposition graft and were randomly treatment with vehicle (control) or single-dose (3 mg/kg, preoperative) or double-dose (3 mg/kg, preoperative and 4 d postoperative) CBS3830. Twenty rats underwent sham operation. The levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) were determined by ELISA. Vein grafts were analyzed by intimal/medial morphometry, proliferating cell nuclear antigen (PCNA) expression, and p38MAPK phosphorylation. RESULTS TNF-α, IL-1β, and IL-6 gradually increased then slowly decreased in AVG rats. However, at 4 d and 7 d, TNF-α levels decreased by 37.5% and 29.5% (p = 0.003, 0.05, respectively) in the single-dose CBS3830 group, and by 37.6% and 32.5%, respectively (both p = 0.003) in the double-dose group compared with those of control. IL-1β levels significantly reduced at 4 d and 14 d in both dosage groups. IL-6 levels significantly reduced at 7 d in both groups. Intima and medial thickening were significantly reduced in both dosage treated groups at 7, 14, and 28 d (all p = 0.000) compared to the controls. Further study showed CBS3830 inhibited p38MAPK phosphorylation and decreased PCNA expression. CONCLUSIONS CBS3830 significantly decreases inflammation and intimal hyperplasia in AVGs.
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Affiliation(s)
- Zhi-Wei Zhao
- The Cardiovascular Research Institute Laboratory, Department of Cardiovascular Surgery, 1st Hospital of Anhui Medical University , Hefei, Anhui , China
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From proliferation to proliferation: monocyte lineage comes full circle. Semin Immunopathol 2014; 36:137-48. [PMID: 24435095 DOI: 10.1007/s00281-013-0409-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 11/25/2013] [Indexed: 12/15/2022]
Abstract
Monocytes are mononuclear circulating phagocytes that originate in the bone marrow and give rise to macrophages in peripheral tissue. For decades, our understanding of monocyte lineage was bound to a stepwise model that favored an inverse relationship between cellular proliferation and differentiation. Sophisticated molecular and surgical cell tracking tools have transformed our thinking about monocyte topo-ontogeny and function. Here, we discuss how recent studies focusing on progenitor proliferation and differentiation, monocyte mobilization and recruitment, and macrophage differentiation and proliferation are reshaping knowledge of monocyte lineage in steady state and disease.
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Robbins CS, Hilgendorf I, Weber GF, Theurl I, Iwamoto Y, Figueiredo JL, Gorbatov R, Sukhova GK, Gerhardt LMS, Smyth D, Zavitz CCJ, Shikatani EA, Parsons M, van Rooijen N, Lin HY, Husain M, Libby P, Nahrendorf M, Weissleder R, Swirski FK. Local proliferation dominates lesional macrophage accumulation in atherosclerosis. Nat Med 2013; 19:1166-72. [PMID: 23933982 PMCID: PMC3769444 DOI: 10.1038/nm.3258] [Citation(s) in RCA: 759] [Impact Index Per Article: 69.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 05/29/2013] [Indexed: 12/22/2022]
Abstract
During the inflammatory response that drives atherogenesis, macrophages accumulate progressively in the expanding arterial wall1,2. The observation that circulating monocytes give rise to lesional macrophages3–9 has reinforced the concept that monocyte infiltration dictates macrophage build-up. Recent work indicates, however, that macrophages do not depend on monocytes in some inflammatory contexts10. We therefore revisited the mechanism of macrophage accumulation in atherosclerosis. We show that murine atherosclerotic lesions experience a surprisingly rapid, 4-week, cell turnover. Replenishment of macrophages in these experimental atheromata depends predominantly on local macrophage proliferation rather than monocyte influx. The microenvironment orchestrates macrophage proliferation via the involvement of scavenger receptor (SR)-A. Our study reveals macrophage proliferation as a key event in atherosclerosis and identifies macrophage self-renewal as a therapeutic target for cardiovascular disease.
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Affiliation(s)
- Clinton S Robbins
- 1] Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA. [2] Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada. [3] Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada. [4] Department of Immunology, University of Toronto, Toronto, Ontario, Canada. [5]
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Majka SM, Miller HL, Sullivan T, Erickson PF, Kong R, Weiser-Evans M, Nemenoff R, Moldovan R, Morandi SA, Davis JA, Klemm DJ. Adipose lineage specification of bone marrow-derived myeloid cells. Adipocyte 2012; 1:215-229. [PMID: 23700536 PMCID: PMC3609111 DOI: 10.4161/adip.21496] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
We have reported the production of white adipocytes in adipose tissue from hematopoietic progenitors arising from bone marrow. However, technical challenges have hindered detection of this adipocyte population by certain other laboratories. These disparate results highlight the need for sensitive and definitive techniques to identify bone marrow progenitor (BMP)-derived adipocytes. In these studies we exploited new models and methods to enhance detection of this adipocyte population. Here we showed that confocal microscopy with spectrum acquisition could effectively identify green fluorescent protein (GFP) positive BMP-derived adipocytes by matching their fluorescence spectrum to that of native GFP. Likewise, imaging flow cytometry made it possible to visualize intact unilocular and multilocular GFP-positive BMP-derived adipocytes and distinguished them from non-fluorescent adipocytes and cell debris in the cytometer flow stream. We also devised a strategy to detect marker genes in flow-enriched adipocytes from which stromal cells were excluded. This technique also proved to be an efficient means for detecting genetically labeled adipocytes and should be applicable to models in which marker gene expression is low or absent. Finally, in vivo imaging of mice transplanted with BM from adipocyte-targeted luciferase donors showed a time-dependent increase in luciferase activity, with the bulk of luciferase activity confined to adipocytes rather than stromal cells. These results confirmed and extended our previous reports and provided proof-of-principle for sensitive techniques and models for detection and study of these unique cells.
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Imberti B, Casiraghi F, Cugini D, Azzollini N, Cassis P, Todeschini M, Solini S, Sebastiano V, Zuccotti M, Garagna S, Redi CA, Noris M, Morigi M, Remuzzi G. Embryonic stem cells, derived either after in vitro fertilization or nuclear transfer, prolong survival of semiallogeneic heart transplants. THE JOURNAL OF IMMUNOLOGY 2011; 186:4164-74. [PMID: 21389254 DOI: 10.4049/jimmunol.1000654] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tolerance induction toward allogeneic organ grafts represents one of the major aims of transplantation medicine. Stem cells are promising candidates for promoting donor-specific tolerance. In this study, we investigated the immunomodulatory properties of murine embryonic stem cells (ESCs), obtained either by in vitro fertilization (IVF-ESCs) or by nuclear transfer (NT-ESCs), in heart transplant mouse models. IVF-ESCs did not prolong the survival of fully allogeneic cardiac transplants but significantly prolonged the survival of semiallogeneic hearts from the same ESC donor strain for >100 d in 44% of the animals. However, 28% of transplanted animals infused with IVF-ESCs experienced development of a teratoma. NT-ESCs similarly prolonged semiallogeneic heart graft survival (>100 d in 40% of the animals) but were less teratogenic. By in vitro studies, IVF-ESC and NT-ESC immunoregulation was mediated both by cell contact-dependent mechanisms and by the release of soluble factors. By adding specific inhibitors, we identified PGE(2) as a soluble mediator of ESC immunoregulation. Expansion of regulatory T cells was found in lymphoid organs and in the grafts of IVF-ESC- and NT-ESC-tolerized mice. Our study demonstrates that both IVF-ESCs and NT-ESCs modulate recipient immune response toward tolerance to solid organ transplantation, and that NT-ESCs exhibit a lower tendency for teratoma formation. Because NT-ESCs are obtained by NT of a somatic cell from living individuals into an enucleated oocyte, they could represent a source of donor-derived stem cells to induce tolerance to solid organ allograft.
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Affiliation(s)
- Barbara Imberti
- Department of Molecular Medicine, Mario Negri Institute for Pharmacological Research, Bergamo 24125, Italy
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Nahrendorf M, Pittet MJ, Swirski FK. Monocytes: protagonists of infarct inflammation and repair after myocardial infarction. Circulation 2010; 121:2437-45. [PMID: 20530020 DOI: 10.1161/circulationaha.109.916346] [Citation(s) in RCA: 578] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Matthias Nahrendorf
- Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, USA.
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Cardiovascular disease in HIV-infected patients: does HIV infection in and of itself increase cardiovascular risk? Curr Opin HIV AIDS 2009; 3:207-13. [PMID: 19372968 DOI: 10.1097/coh.0b013e3282fb7ba6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE OF REVIEW Cardiovascular disease is increasingly recognized to be a significant cause of morbidity and mortality among patients with chronic HIV infection in the current era of effective antiretroviral therapy. HIV-infected patients treated with antiretroviral therapy have increased traditional cardiovascular risk factors, but whether HIV infection in and of itself confers a significant increase in cardiovascular risk is largely unknown. This review summarizes recent data investigating cardiovascular risk in HIV patients and the evidence for an effect of HIV per se. The potential physiological mechanisms by which HIV might contribute to coronary artery disease are reviewed. RECENT FINDINGS Several interesting studies in the last year have evaluated cardiovascular endpoints and surrogate measures such as carotid intima-media thickness and endothelial function in HIV-infected patients compared with uninfected control groups. Several studies to date using surrogate measurements such as carotid intima-media thickness and endothelial dysfunction suggest a possible independent HIV effect on cardiovascular risk, but some studies have yielded conflicting results. Numerous potential mechanisms by which HIV might contribute to coronary artery disease exist. These mechanisms include effects of HIV proteins to attract monocytes to the intimal wall, and impair cholesterol efflux, and effects of activated monocytes to induce an inflammatory response. SUMMARY More definitive prospective studies are needed to fully answer whether HIV infection per se promotes cardiovascular disease, but ample evidence suggests that HIV and related inflammatory responses could contribute to increased cardiovascular disease.
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Herbert KE, Lévesque JP, Haylock DN, Prince HM. The use of experimental murine models to assess novel agents of hematopoietic stem and progenitor cell mobilization. Biol Blood Marrow Transplant 2008; 14:603-21. [PMID: 18489986 DOI: 10.1016/j.bbmt.2008.02.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2007] [Accepted: 02/04/2008] [Indexed: 01/13/2023]
Abstract
The recent explosion in the understanding of the cellular and molecular mechanisms underlying hematopoietic stem and progenitor cell (HSPC) mobilization has facilitated development of novel therapeutic agents, targeted at improving mobilization kinetics as well as HSPC yield. With the development of new agents comes the challenge of choosing efficient and relevant preclinical studies for the testing of the HSPC mobilization efficacy of these agents. This article reviews the use of the mouse as a convenient small animal model of HSPC mobilization and transplantation, and outlines the range of murine assays that can be applied to assess novel HSPC mobilizing agents. Techniques to demonstrate murine HSPC mobilization are discussed, as well as the role of murine assays to confirm human HSPC mobilization, and techniques to investigate the biologic phenotype of HSPC mobilized by these novel agents. Technical aspects regarding mobilization regimens and control arms, and choice of experimental animals are also discussed.
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Affiliation(s)
- Macrae F Linton
- Atherosclerosis Research Unit, Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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Kircher MF, Grimm J, Swirski FK, Libby P, Gerszten RE, Allport JR, Weissleder R. Noninvasive in vivo imaging of monocyte trafficking to atherosclerotic lesions. Circulation 2008; 117:388-95. [PMID: 18172031 DOI: 10.1161/circulationaha.107.719765] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Monocytes play a key role in atherogenesis, but their participation has been discerned largely via ex vivo analyses of atherosclerotic lesions. We sought to establish a noninvasive technique to determine monocyte trafficking to atherosclerotic lesions in live animals. METHODS AND RESULTS Using a micro-single-photon emission computed tomography small-animal imaging system and a Food and Drug Administration-approved radiotracer ([indium 111] oxyquinoline, (111)In-oxine), we demonstrate here that monocyte recruitment to atherosclerotic lesions can be visualized in a noninvasive, dynamic, and 3-dimensional fashion in live animals. We show in vivo that monocytes are recruited avidly to plaques within days of adoptive transfer. Using micro-single-photon emission computed tomography imaging as a screening tool, we were able to investigate modulatory effects on monocyte recruitment in live animals. We found that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors rapidly and substantially reduce monocyte recruitment to existing atherosclerotic lesions, as imaged here in vivo. CONCLUSIONS This novel approach to track monocytes to atherosclerotic plaques in vivo should have broad applications and create new insights into the pathogenesis of atherosclerosis and other inflammatory diseases.
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Affiliation(s)
- Moritz F Kircher
- Center for Molecular Imaging Research, Massachusetts General Hospital and Harvard Medical School, Charlestown, Mass, USA
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Swirski FK, Libby P, Aikawa E, Alcaide P, Luscinskas FW, Weissleder R, Pittet MJ. Ly-6Chi monocytes dominate hypercholesterolemia-associated monocytosis and give rise to macrophages in atheromata. J Clin Invest 2007; 117:195-205. [PMID: 17200719 PMCID: PMC1716211 DOI: 10.1172/jci29950] [Citation(s) in RCA: 971] [Impact Index Per Article: 57.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Accepted: 10/24/2006] [Indexed: 12/14/2022] Open
Abstract
Macrophage accumulation participates decisively in the development and exacerbation of atherosclerosis. Circulating monocytes, the precursors of macrophages, display heterogeneity in mice and humans, but their relative contribution to atherogenesis remains unknown. We report here that the Ly-6C(hi) monocyte subset increased dramatically in hypercholesterolemic apoE-deficient mice consuming a high-fat diet, with the number of Ly-6C(hi) cells doubling in the blood every month. Ly-6C(hi) monocytes adhered to activated endothelium, infiltrated lesions, and became lesional macrophages. Hypercholesterolemia-associated monocytosis (HAM) developed from increased survival, continued cell proliferation, and impaired Ly-6C(hi) to Ly-6C(lo) conversion and subsided upon statin-induced cholesterol reduction. Conversely, the number of Ly-6C(lo) cells remained unaffected. Thus, we believe that Ly-6C(hi) monocytes represent a newly recognized component of the inflammatory response in experimental atherosclerosis.
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Affiliation(s)
- Filip K Swirski
- Center for Molecular Imaging Research, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA.
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Swirski FK, Pittet MJ, Kircher MF, Aikawa E, Jaffer FA, Libby P, Weissleder R. Monocyte accumulation in mouse atherogenesis is progressive and proportional to extent of disease. Proc Natl Acad Sci U S A 2006; 103:10340-10345. [PMID: 16801531 PMCID: PMC1502459 DOI: 10.1073/pnas.0604260103] [Citation(s) in RCA: 279] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Monocytes participate importantly in the pathogenesis of atherosclerosis, but their spatial and temporal recruitment from circulation remains uncertain. This study tests the hypothesis that monocyte accumulation in atheroma correlates with the extent of disease by using a sensitive and simple quantitative assay that allows tracking of highly enriched populations of blood monocytes. A two-step isolation method yielded viable and functionally intact highly enriched peripheral blood monocyte populations (>90%). Recipient mice received syngeneic monocytes labeled in two ways: by transgenically expressing EGFP or with a radioactive tracer [(111)In]oxine. After 5 days, more labeled cells accumulated in the aorta, principally the aortic root and ascending aorta, of 10-wk-old ApoE(-/-) compared with 10-wk-old C57BL/6 mice (223 +/- 3 vs. 87 +/- 22 cells per aorta). Considerably more monocytes accumulated in 20-wk-old ApoE(-/-) mice on either chow (314 +/- 41 cells) or high-cholesterol diet (395 +/- 53 cells). Fifty-week-old ApoE(-/-) mice accumulated even more monocytes in the aortic root, ascending aorta, and thoracic aorta after both chow (503 +/- 67 cells) or high-cholesterol diet (648 +/- 81 cells). Labeled monocyte content in the aorta consistently correlated with lesion surface area. These data indicate that monocytes accumulate continuously during atheroma formation, accumulation increases in proportion to lesion size, and recruitment is augmented with hypercholesterolemia. These results provide insights into mechanisms of atherogenesis and have implications for the duration of therapies directed at leukocyte recruitment.
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Affiliation(s)
- Filip K Swirski
- *Center for Molecular Imaging Research and Donald W. Reynolds Cardiovascular Clinical Research Center on Atherosclerosis at Harvard Medical School, Massachusetts General Hospital and Harvard Medical School, CNY 149, Charlestown, MA 02129; and
- Cardiovascular Division, Department of Medicine and Donald W. Reynolds Cardiovascular Clinical Research Center on Atherosclerosis at Harvard Medical School, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115
| | - Mikael J Pittet
- *Center for Molecular Imaging Research and Donald W. Reynolds Cardiovascular Clinical Research Center on Atherosclerosis at Harvard Medical School, Massachusetts General Hospital and Harvard Medical School, CNY 149, Charlestown, MA 02129; and
| | - Moritz F Kircher
- *Center for Molecular Imaging Research and Donald W. Reynolds Cardiovascular Clinical Research Center on Atherosclerosis at Harvard Medical School, Massachusetts General Hospital and Harvard Medical School, CNY 149, Charlestown, MA 02129; and
| | - Elena Aikawa
- *Center for Molecular Imaging Research and Donald W. Reynolds Cardiovascular Clinical Research Center on Atherosclerosis at Harvard Medical School, Massachusetts General Hospital and Harvard Medical School, CNY 149, Charlestown, MA 02129; and
| | - Farouc A Jaffer
- *Center for Molecular Imaging Research and Donald W. Reynolds Cardiovascular Clinical Research Center on Atherosclerosis at Harvard Medical School, Massachusetts General Hospital and Harvard Medical School, CNY 149, Charlestown, MA 02129; and
| | - Peter Libby
- Cardiovascular Division, Department of Medicine and Donald W. Reynolds Cardiovascular Clinical Research Center on Atherosclerosis at Harvard Medical School, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA 02115
| | - Ralph Weissleder
- *Center for Molecular Imaging Research and Donald W. Reynolds Cardiovascular Clinical Research Center on Atherosclerosis at Harvard Medical School, Massachusetts General Hospital and Harvard Medical School, CNY 149, Charlestown, MA 02129; and
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Abstract
BACKGROUND Inflammation has received increasing attention in recent years as a cause of atherosclerosis, coronary artery disease, and stroke. Basic and animal research has implicated inflammatory mechanisms in the pathogenesis and progression of atherosclerosis, as well as in clinical events related to plaque rupture and other atherothrombotic events. REVIEW SUMMARY The literature on the association of inflammatory markers with risk of stroke was reviewed and a clinical example provided. Several inflammatory biomarkers, and particularly high-sensitivity C-reactive protein (hsCRP), have been identified as likely predictors of the risk of a future stroke. Medications, particularly hydroxymethylglutaryl coenzyme A reductase inhibitors, or statins, have been demonstrated to reduce levels of inflammatory markers independently of effects on cholesterol. Most recently, the ability of these agents to reduce risk of myocardial infarction and other coronary events in patients with acute coronary artery disease has been demonstrated to correlate with their ability to lower levels of hsCRP. Whether reduction of hsCRP would have similar benefits in stroke patients remains unsettled, as does whether other drugs may be similarly used to lower hsCRP levels. CONCLUSION Inflammatory biomarkers, especially hsCRP, may allow improved prediction of the risk of stroke in primary and secondary stroke prevention. Modalities to reduce inflammation are becoming available that may help to modify this risk. Further studies, however, are needed before inflammatory markers become a routine part of the evaluation of stroke patients.
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Affiliation(s)
- Mitchell S V Elkind
- Department of Neurology, Columbia University, New York, New York 10032, USA.
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17
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Mitra AK, Del Core MG, Agrawal DK. Cells, cytokines and cellular immunity in the pathogenesis of fibroproliferative vasculopathies. Can J Physiol Pharmacol 2006; 83:701-15. [PMID: 16333372 DOI: 10.1139/y05-080] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Atherosclerosis and restenosis are the result of vascular injury followed by an inflammatory and fibroproliferative response that involves a large number of growth factors, cytokines, and cellular elements. Platelet activation and leukocyte recruitment into the arterial intima play a crucial role, initiating a whole spectrum of reactions leading to vascular smooth muscle cell hyperplasia and intimal migration. The roles of macrophages and lymphocytes and mast cells as mediators of inflammation and immune response is discussed, as are the roles of growth factors and cytokines. New light on the 'old' problems will help us to devise newer and better therapeutic strategies to combat these clinical entities.
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Affiliation(s)
- Amit K Mitra
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, NE 68178, USA
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18
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Yancy AD, Olzinski AR, Hu TCC, Lenhard SC, Aravindhan K, Gruver SM, Jacobs PM, Willette RN, Jucker BM. Differential uptake of ferumoxtran-10 and ferumoxytol, ultrasmall superparamagnetic iron oxide contrast agents in rabbit: critical determinants of atherosclerotic plaque labeling. J Magn Reson Imaging 2005; 21:432-42. [PMID: 15779033 DOI: 10.1002/jmri.20283] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PURPOSE To compare atherosclerotic plaque uptake of a first (ferumoxtran-10) and second generation (ferumoxytol) ultrasmall superparamagnetic iron oxide (USPIO) contrast agent with different pharmacokinetic/pharmacodynamic properties. MATERIALS AND METHODS New Zealand White rabbits maintained on a high cholesterol/fat diet were subjected to balloon injury to the abdominal aorta. Ferumoxtran-10 or ferumoxytol (500 micromol/kg) was administered at 2, 4, and 8 weeks following injury. In vivo magnetic resonance imaging (MRI) was performed immediately prior to, immediately after, and 6 days post-contrast administration. Ex vivo MRI, histologic, and inductively coupled plasma-mass spectrometry (ICP-MS) iron analyses were performed on the excised vessels. RESULTS The blood pool clearance of ferumoxytol (t(1/2) < or = 6 hours) was more rapid than that of ferumoxtran-10 (t(1/2) < or = 48 hours). Decreased in vivo MRI signal intensity in the abdominal aorta was observed at 2, 4, and 8 weeks following injury with ferumoxtran-10, but not with ferumoxytol. Consistent with these observations, ex vivo MRI signal intensity was decreased in the ferumoxtran-10 vessels, and to a lesser degree in the ferumoxytol vs. control vessels (- contrast agent). In contrast, in vitro macrophage phagocytosis of USPIO was four to six fold greater with ferumoxytol than with ferumoxtran-10. Additionally, the absolute iron content correlated with ex vivo MRI signal intensity in all vessels (r = -0.86, P < 0.0001). CONCLUSIONS These data suggest that the exposure period of atherosclerotic plaque to USPIO rather than the kinetics of the USPIO uptake by plaque alone is a critical criterion for experimental design of in vivo studies.
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Affiliation(s)
- April D Yancy
- Laboratory Animal Sciences, GlaxoSmithKline, King of Prussia, Pennsylvania 19406, USA
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19
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Hood MN, Ho VB. Contrast Agents: Innovations and Potential Applications for Body MR Angiography. Magn Reson Imaging Clin N Am 2005; 13:189-203, vii. [PMID: 15760765 DOI: 10.1016/j.mric.2004.12.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Maureen N Hood
- Department of Radiology and Radiological Sciences, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814-4799, USA.
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20
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AbdAlla S, Lother H, Langer A, el Faramawy Y, Quitterer U. Factor XIIIA Transglutaminase Crosslinks AT1 Receptor Dimers of Monocytes at the Onset of Atherosclerosis. Cell 2004; 119:343-54. [PMID: 15507206 DOI: 10.1016/j.cell.2004.10.006] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Many G protein-coupled receptors form dimers in cells. However, underlying mechanisms are barely understood. We report here that intracellular factor XIIIA transglutaminase crosslinks agonist-induced AT1 receptor homodimers via glutamine315 in the carboxyl-terminal tail of the AT1 receptor. The crosslinked dimers displayed enhanced signaling and desensitization in vitro and in vivo. Inhibition of angiotensin II release or of factor XIIIA activity prevented formation of crosslinked AT1 receptor dimers. In agreement with this finding, factor XIIIA-deficient individuals lacked crosslinked AT1 dimers. Elevated levels of crosslinked AT1 dimers were present on monocytes of patients with the common atherogenic risk factor hypertension and correlated with an enhanced angiotensin II-dependent monocyte adhesion to endothelial cells. Elevated levels of crosslinked AT1 receptor dimers on monocytes could sustain the process of atherogenesis, because inhibition of angiotensin II generation or of intracellular factor XIIIA activity suppressed the appearance of crosslinked AT1 receptors and symptoms of atherosclerosis in ApoE-deficient mice.
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Affiliation(s)
- Said AbdAlla
- Heinrich-Pette-Institut, Martinistrasse 52, D-20251 Hamburg, Germany
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21
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Suarez EC, Lewis JG, Krishnan RR, Young KH. Enhanced expression of cytokines and chemokines by blood monocytes to in vitro lipopolysaccharide stimulation are associated with hostility and severity of depressive symptoms in healthy women. Psychoneuroendocrinology 2004; 29:1119-28. [PMID: 15219635 DOI: 10.1016/j.psyneuen.2004.01.002] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2003] [Revised: 12/30/2003] [Accepted: 01/05/2004] [Indexed: 01/21/2023]
Abstract
The current study investigated the relation of hostility and severity of depressive symptoms, separately and jointly, to the capacity of blood monocytes to secrete an array of cytokines when stimulated by bacterial lipopolysaccharide (LPS). Subjects were 44 healthy, non-smoking, premenopausal women (aged 23-49 years) not currently taking oral contraceptives. Data were collected during the follicular phase of the menstrual cycle. The Cook-Medley Hostility (Ho) scale and the Beck Depression Inventory (BDI) were used to assess hostility and severity of depressive symptoms, respectively. Dual-color flow cytometry was used to measure the total expression of interleukin (IL)-1alpha, IL-1beta, IL-8, tumor necrosis factor (TNF)-alpha, monocyte chemotactic protein (MCP)-1 and monocyte inflammatory protein (MIP)-1alpha in blood monocytes following 4 h in vitro LPS stimulation of whole blood. In analyses adjusting for age, body mass index (BMI), fasting cholesterol, alcohol use, race and 17beta-estradiol (E(2)), higher Ho scores were associated with greater LPS-stimulated expression of IL-1alpha (beta = 0.033, p = 0.02), IL-8 (beta = 0.046, p = 0.01) and IL-1beta (beta = 0.024, p = 0.06). Higher BDI scores were associated with greater expression of TNF-alpha (beta = 0.042, p = 0.02) and IL-8 (beta = 0.045, p = 0.04). The linear combination of Ho and BDI scores was significantly associated with IL-1beta (beta = 0.18, p = 0.057), IL-8 (beta = 0.36, p = 0.01), TNF-alpha (beta = 0.25, p = 0.03), and IL-1alpha (beta = 0.18, p < 0.07). Thus, in healthy women, these psychological risk factors, alone and in combination, induce a proinflammatory phenotype in circulating monocytes characterized by the up-regulation of proinflammatory cytokines, supporting the hypothesis that inflammation may be a key pathway whereby hostility and depressive symptoms contribute to atherosclerosis and subsequent coronary heart disease (CHD).
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Affiliation(s)
- Edward C Suarez
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, P.O. Box 3328, Durham, NC 27710, USA.
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22
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Portugal LR, Fernandes LR, Cesar GC, Santiago HC, Oliveira DR, Silva NM, Silva AA, Lannes-Vieira J, Arantes RME, Gazzinelli RT, Alvarez-Leite JI. Infection with Toxoplasma gondii increases atherosclerotic lesion in ApoE-deficient mice. Infect Immun 2004; 72:3571-6. [PMID: 15155666 PMCID: PMC415665 DOI: 10.1128/iai.72.6.3571-3576.2004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii is an intracellular protozoan that elicits a potent inflammatory response during the acute phase of infection. Herein, we evaluate whether T. gondii infection alters the natural course of aortic lesions. ApoE knockout mice were infected with T. gondii, and at 5 weeks of infection, serum, feces, and liver cholesterol; aortic lesion size, cellularity, and inflammatory cytokines; and levels of serum nitrite and gamma interferon (IFN-gamma) were analyzed. Our results showed that serum cholesterol and atherogenic lipoproteins were reduced after T. gondii infection. The reduction of serum levels of total cholesterol and atherogenic lipoproteins was associated with increases in the aortic lesion area, numbers of inflammatory cells, and expression of monocyte chemoattractant protein 1 and inducible nitric oxide synthase mRNA in the site of lesions as well as elevated concentrations of IFN-gamma and nitrite in sera of T. gondii-infected animals. These results suggest that infection with T. gondii accelerates atherosclerotic development by stimulating the proinflammatory response and oxidative stress, thereby increasing the area of aortic lesion.
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Affiliation(s)
- Luciane R Portugal
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil
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23
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Moeller F, Nielsen FC, Nielsen LB. New tools for quantifying and visualizing adoptively transferred cells in recipient mice. J Immunol Methods 2004; 282:73-82. [PMID: 14604542 DOI: 10.1016/j.jim.2003.07.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Adoptive transfer of donor cells in mice is widely used in research on the function and metabolism of lymphocytes. We have evaluated new approaches for quantifying and visualizing adopted cells in recipient mouse tissue. We injected spleen cells from male beta-galactosidase (LacZ) transgenic mice into female wild type mice and assessed the robustness of real-time PCR for quantifying the accumulation of the donor cells in blood and tissues of the recipient mice. The clearance of donor cells from the blood and their recruitment in lung, spleen, liver, and kidney was almost identical when obtained with amplification of the donor cell-specific LacZ or sex-determining region on the Y-chromosome (SRY) gene. We found, however, a marked difference in the PCR amplification efficiency of genomic DNA of different tissues, which should be taken into account when comparing recruitment of donor cells in different tissues. To visualize adoptively transferred cells, we used either spleen cells from transgenic mice, which express a Green Fluorescent Protein (GFP) transgene or spleen cells that had been fluorescence labeled ex vivo with CellTracker Orange. Whereas ex vivo and in vivo labeled donor cells could easily be detected in recipient mouse tissue by laser scanning confocal microscopy, only CellTracker Orange-labeled cells could be detected by conventional fluorescence microscopy due to autofluorescence in the examined tissues. Importantly, CellTracker Orange labeling did not appear to affect the blood clearance or the tissue accumulation of the donor cells. Together, the results demonstrate the usefulness of new protocols for quantifying and visualizing adoptively transferred cells by genetic tracing or fluorescence labeling.
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Affiliation(s)
- Flemming Moeller
- Department of Clinical Biochemistry, KB3011, Copenhagen University Hospital, Blegdamsvej 9, DK-2100, Denmark
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24
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Collagen Vascular and Infectious Diseases. Stroke 2004. [DOI: 10.1016/b0-44-306600-0/50030-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Vamvakopoulos JE, Green C. HMG-CoA reductase inhibition aborts functional differentiation and triggers apoptosis in cultured primary human monocytes: a potential mechanism of statin-mediated vasculoprotection. BMC Cardiovasc Disord 2003; 3:6. [PMID: 12871602 PMCID: PMC183828 DOI: 10.1186/1471-2261-3-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2003] [Accepted: 07/19/2003] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Statins effectively lower blood cholesterol and the risk of cardiovascular death. Immunomodulatory actions, independent of their lipid-lowering effect, have also been ascribed to these compounds. Since macrophages participate in several vascular pathologies, we examined the effect of statin treatment on the survival and differentiation of primary human monocytes. METHODS Peripheral blood mononuclear cells (PBMCs) from healthy individuals were cultured in the presence or absence of mevastatin. Apoptosis was monitored by annexin V / PI staining and flow cytometry. In parallel experiments, cultures were stimulated with LPS in the presence or absence of mevastatin and the release of IL-1beta and IL-1Ra was measured by ELISA. RESULTS Among PBMCs, mevastatin-treated monocytes were particularly susceptible to apoptosis, which occurred at doses >1 microM and was already maximal at 5 microM. However, even at the highest mevastatin dose used (10 microM), apoptosis occurred only after 24 h of culture, possibly reflecting a requirement for cell commitment to differentiation. After 72 h of treatment the vast majority (>50%) of monocytes were undergoing apoptosis. Stimulation with LPS revealed that mevastatin-treated monocytes retained the high IL-1beta output characteristic of undifferentiated cells; conversely, IL-1Ra release was inhibited. Concurrent treatment with mevalonolactone prevented the induction of apoptosis and suppressed both IL-1beta and IL-1Ra release in response to LPS, suggesting a rate-limiting role for HMG-CoA reductase in monocyte differentiation. CONCLUSIONS Our findings indicate that statins arrest the functional differentiation of monocytes into macrophages and steer these cells into apoptosis, suggesting a novel mechanism for the vasculoprotective properties of HMG-CoA reductase inhibitors.
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Affiliation(s)
- Joannis E Vamvakopoulos
- Department of Surgery, University of Cambridge, Cambridge, UK
- Current address: Rational Drug Design Program, Biomedicum Helsinki, Helsinki, Finland
| | - Colin Green
- Northwick Park Institute for Medical Research, Harrow, UK
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26
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Moeller F, Nielsen LB. Aortic recruitment of blood lymphocytes is most pronounced in early stages of lesion formation in apolipoprotein-E-deficient mice. Atherosclerosis 2003; 168:49-56. [PMID: 12732386 DOI: 10.1016/s0021-9150(03)00026-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Lymphocyte accumulation in the arterial intima affects development of atherosclerotic lesions. We studied the kinetics of lymphocyte accumulation in the arterial wall by injecting lymphocytes from male LacZ transgenic mice into female apolipoprotein-E-deficient mice. Recipient mouse aortas were removed and separated into lesioned and non-lesioned parts 2, 24, 48, or 72 h later. The accumulation of donor lymphocytes was quantified with real-time PCR of donor lymphocyte-specific genes. The accumulation of lymphocytes in the lesioned parts of aorta decreased with increasing lesion severity (r=-0.74, P=0.0005, n=18). Moreover, the accumulation of lymphocytes in the lesioned part of aorta was larger (392+/-108%, P=0.016) compared with the accumulation in the non-lesioned part in mice with mild atherosclerosis, whereas it was smaller (58+/-19%, P<0.01) compared with the accumulation in the non-lesioned part in mice with severe atherosclerosis. The results suggest that aortic recruitment of blood lymphocytes is most pronounced in early stages of lesion formation.
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Affiliation(s)
- Flemming Moeller
- Department of Clinical Biochemistry, Copenhagen University Hospital, KB3011, Blegdamsvej 9, Denmark
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27
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Lessner SM, Prado HL, Waller EK, Galis ZS. Atherosclerotic lesions grow through recruitment and proliferation of circulating monocytes in a murine model. THE AMERICAN JOURNAL OF PATHOLOGY 2002; 160:2145-55. [PMID: 12057918 PMCID: PMC1850830 DOI: 10.1016/s0002-9440(10)61163-7] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Macrophage-derived foam cells in developing atherosclerotic lesions may potentially originate either from recruitment of circulating monocytes or from migration of resident tissue macrophages. In this study, we have determined the source of intimal macrophages in the apoE-knockout mouse flow-cessation/hypercholesterolemia model of atherosclerosis using a bone marrow transplantation approach. We also examined the time course and spatial distribution of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 expression to assess whether endothelial adhesion molecules were involved in recruitment of either circulating monocytes or resident macrophages. We used allelic variants of the mouse common leukocyte antigen (CD45) to distinguish host-derived and donor-derived white blood cells (WBCs) both in blood and in macrophage-rich carotid lesions. We found that the distribution of CD45 isoforms in lesions is similar to that of circulating WBCs, whereas the host-type CD45 isoform is more prevalent in resident adventitial macrophages. These data indicate that macrophage-derived foam cells in the lesion derive mainly from circulating precursors rather than from resident macrophages. The corresponding time course of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 expression suggests that recruitment of circulating WBCs by endothelial adhesion molecules is likely to be more important during lesion initiation than during the later phase of rapid lesion growth.
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Affiliation(s)
- Susan M Lessner
- Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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28
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Paik JY, Lee KH, Byun SS, Choe YS, Kim BT. Use of insulin to improve [18 F]fluorodeoxyglucose labelling and retention for in vivo positron emission tomography imaging of monocyte trafficking. Nucl Med Commun 2002; 23:551-7. [PMID: 12029210 DOI: 10.1097/00006231-200206000-00007] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
While 18F-FDG labelling of monocytes would allow in vivo trafficking with positron emission tomography (PET), present methods suffer from poor retention of radioactivity. We investigated the feasibility of utilizing insulin for improved [18F]fluorodeoxyglucose (18F-FDG) labelling. Separated human monocytes and lymphocytes were labelled with 18F-FDG with or without 3 h insulin pre-incubation. Insulin had no effect on lymphocyte labelling (21.4+/-0.8% vs 20.8+/-1.1% efficiency, P=NS). However, for monocytes, insulin pre-incubation led to a 169+/-9% increase in labelling efficiency (19.3+/-4.1 vs 32.5+/-1.8, P<0.05), without significant effects on cell activation or viability. Moreover, while only 57.7+/-4.8% and 40.4+/-5.6% of the 18F-FDG was retained at 1 and 3 h for controls, the retention rate increased to 91.6+/-2.1% (P=0.01) and 86.5+/-1.9% (P<0.01) after insulin pre-incubation. Improved 18F-FDG retention was accompanied by a 70.3+/-7.4% decrease in glucose-6-phosphatase activity (P=0.02). PET imaging of rats showing hepatic ischaemia-reperfusion injury demonstrated higher liver uptake for monocytes labelled after insulin treatment. Thus, insulin improves monocytic 18F-FDG uptake and retention, and may provide a feasible labelling method for PET imaging.
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Affiliation(s)
- J-Y Paik
- Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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29
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Abstract
During the past year studies with mouse models have significantly clarified our understanding of atherosclerosis. Noteworthy achievements include: the discovery of a number of novel genes and pathways; new evidence emphasizing the role of lymphocytes in atherogenesis; the development of mouse models exhibiting advanced lesions with evidence of thrombosis; and new results indicating an anti-atherogenic effect of testosterone.
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Affiliation(s)
- Sonal S Sheth
- Department of Human Genetics, UCLA School of Medicine, Los Angeles, California 90095, USA
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30
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Cytokines and the pathogenesis of atherosclerosis. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1566-3124(02)11027-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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31
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Haskell CA, Hancock WW, Salant DJ, Gao W, Csizmadia V, Peters W, Faia K, Fituri O, Rottman JB, Charo IF. Targeted deletion of CX(3)CR1 reveals a role for fractalkine in cardiac allograft rejection. J Clin Invest 2001; 108:679-88. [PMID: 11544273 PMCID: PMC209384 DOI: 10.1172/jci12976] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Fractalkine (Fk) is a structurally unusual member of the chemokine family. To determine its role in vivo, we generated mice with a targeted disruption of CX(3)CR1, the receptor for Fk. CX(3)CR1(-/-) mice were phenotypically indistinguishable from wild-type mice in a pathogen-free environment. In response to antibody-induced glomerulonephritis, CX(3)CR1(-/-) and CX(3)CR1(+/+) mice had similar levels of proteinuria and injury. CX(3)CR1(-/-) and CX(3)CR1(+/+) mice also developed similar levels of disease in myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis. We performed heterotopic MHC class I/II cardiac transplants from BALB/c mice into C57BL/6 mice. In the absence of cyclosporin A (CsA), there was no difference in graft survival time between CX(3)CR1(-/-) and CX(3)CR1(+/+) recipient mice. However, in the presence of subtherapeutic levels of CsA, graft survival time was significantly increased in the CX(3)CR1(-/-) mice. Characterization of cells infiltrating the grafts revealed a selective reduction in natural killer cells in the CX(3)CR1(-/-) recipients in the absence of CsA and a reduction in macrophages, natural killer cells, and other leukocytes in the presence of CsA. We conclude that Fk plays an important role in graft rejection. The development of CX(3)CR1 antagonists may allow reductions in the doses of immunosuppressive drugs used in transplantation.
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Affiliation(s)
- C A Haskell
- Gladstone Institute of Cardiovascular Disease, San Francisco, California 94141-9100, USA
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Abstract
Atherosclerosis bears many features of a chronic inflammation that affects the intima of large and medium-sized arteries. In recent years apolipoprotein E-deficient and LDL receptor-deficient mice have been used to examine the effects of various gene products on the development of atherosclerosis. In the present review the effects of genetics, apolipoprotein E, inflammatory gene modifiers, lipoprotein modifications, lipoprotein receptors, vessel wall expression of lipoprotein-metabolizing enzymes, and the atheroprotective role of HDL on atherosclerosis in these mice are discussed. The importance of examining lesions that are more advanced than fatty streaks and careful histologic and immunologic examination of lesion composition is emphasized.
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Affiliation(s)
- C A Reardon
- Department of Pathology, The University of Chicago, Chicago, Illinois 60637, USA
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33
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Peters W, Charo IF. Involvement of chemokine receptor 2 and its ligand, monocyte chemoattractant protein-1, in the development of atherosclerosis: lessons from knockout mice. Curr Opin Lipidol 2001; 12:175-80. [PMID: 11264989 DOI: 10.1097/00041433-200104000-00011] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Blood monocytes are the precursors of the lipid-laden foam cells that are the hallmark of early atherosclerotic lesions, but the signals that initiate their recruitment to the vessel wall are poorly understood. Here, we review in vivo studies in genetically altered mice that support the notion that monocyte chemoattractant protein-1 (a member of the chemokine family of chemotactic cytokines) and chemokine receptor 2 (its cognate receptor) play important roles in this recruitment. An unexpected finding in chemokine receptor 2-knockout mice was the diminished production of interferon-gamma, which is a potent macrophage activator. The basis of this cytokine defect is not yet clear, but suggests that chemokines may influence atherosclerotic lesion development at several levels. Understanding the roles of chemokines and cytokines in atherogenesis may provide a basis for the development of future therapeutic agents that are aimed at interrupting monocyte recruitment and activation.
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Affiliation(s)
- W Peters
- Gladstone Institute of Cardiovascular Disease, and Cardiovascular Research Institute, Department of Medicine, University of California, San Francisco, California 94141-9100, USA
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