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Xie Y, Jia Y, Li Z, Hu F. Scavenger receptor A in immunity and autoimmune diseases: Compelling evidence for targeted therapy. Expert Opin Ther Targets 2022; 26:461-477. [PMID: 35510370 DOI: 10.1080/14728222.2022.2072729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Scavenger receptor A (SR-A) is reported to be involved in innate and adaptive immunity and in recent years, the soluble form of SR-A has also been identified. Intriguingly, SR-A displays double-edged sword features in different diseases. Moreover, targeted therapy on SR-A, including genetic modulation, small molecule inhibitor, inhibitory peptides, fucoidan, and blocking antibodies, provides potential strategies for treatment. Currently, therapeutics targeting SR-A are in preclinical studies and clinical trials, revealing great perspectives in future immunotherapy. AREAS COVERED Through searching PubMed (January 1979-March 2022) and clinicaltrials.gov, we review most of the research and clinical trials involving SR-A. This review briefly summarizes recent study advances on SR-A, with particular concern on its role in immunity and autoimmune diseases. EXPERT OPINION Given the emerging evidence of SR-A in immunity, its targeted therapy has been studied in various diseases, especially autoimmune diseases. However, many challenges still remain to be overcome, such as the double-sworded effects and the specific isoform targeting. For further clinical success of SR-A targeted therapy, the crystal structure illustration and the dual function discrimination of SR-A should be further investigated. Nevertheless, although challenging, targeting SR-A would be a potential effective strategy in the treatment of autoimmune diseases and other immune-related diseases.
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Affiliation(s)
- Yang Xie
- Department of Rheumatology and Immunology, Peking University People's Hospital & Beijing Key Laboratory for Rheumatism Mechanism and Immune Diagnosis (BZ0135), Beijing, Peking, China
| | - Yuan Jia
- Department of Rheumatology and Immunology, Peking University People's Hospital & Beijing Key Laboratory for Rheumatism Mechanism and Immune Diagnosis (BZ0135), Beijing, Peking, China
| | - Zhanguo Li
- Department of Rheumatology and Immunology, Peking University People's Hospital & Beijing Key Laboratory for Rheumatism Mechanism and Immune Diagnosis (BZ0135), Beijing, Peking, China.,State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, Peking, China.,Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, Peking, China
| | - Fanlei Hu
- Department of Rheumatology and Immunology, Peking University People's Hospital & Beijing Key Laboratory for Rheumatism Mechanism and Immune Diagnosis (BZ0135), Beijing, Peking, China.,State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing, Peking, China.,Department of Integration of Chinese and Western Medicine, School of Basic Medical Sciences, Peking University, Beijing, Peking, China
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Liu Z, Zhu H, Dai X, Wang C, Ding Y, Song P, Zou MH. Macrophage Liver Kinase B1 Inhibits Foam Cell Formation and Atherosclerosis. Circ Res 2017; 121:1047-1057. [PMID: 28827412 PMCID: PMC5640502 DOI: 10.1161/circresaha.117.311546] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/13/2017] [Accepted: 08/21/2017] [Indexed: 01/01/2023]
Abstract
RATIONALE LKB1 (liver kinase B1) is a serine/threonine kinase and tumor suppressor, which regulates the homeostasis of hematopoietic cells and immune responses. Macrophages transform into foam cells upon taking-in lipids. No role for LKB1 in foam cell formation has previously been reported. OBJECTIVE We sought to establish the role of LKB1 in atherosclerotic foam cell formation. METHODS AND RESULTS LKB1 expression was examined in human carotid atherosclerotic plaques and in western diet-fed atherosclerosis-prone Ldlr-/- and ApoE-/- mice. LKB1 expression was markedly reduced in human plaques when compared with nonatherosclerotic vessels. Consistently, time-dependent reduction of LKB1 levels occurred in atherosclerotic lesions in western diet-fed Ldlr-/- and ApoE-/- mice. Exposure of macrophages to oxidized low-density lipoprotein downregulated LKB1 in vitro. Furthermore, LKB1 deficiency in macrophages significantly increased the expression of SRA (scavenger receptor A), modified low-density lipoprotein uptake and foam cell formation, all of which were abolished by blocking SRA. Further, we found LKB1 phosphorylates SRA resulting in its lysosome degradation. To further investigate the role of macrophage LKB1 in vivo, ApoE-/-LKB1fl/flLysMcre and ApoE-/-LKB1fl/fl mice were fed with western diet for 16 weeks. Compared with ApoE-/-LKB1fl/fl wild-type control, ApoE-/-LKB1fl/flLysMcre mice developed more atherosclerotic lesions in whole aorta and aortic root area, with markedly increased SRA expression in aortic root lesions. CONCLUSIONS We conclude that macrophage LKB1 reduction caused by oxidized low-density lipoprotein promotes foam cell formation and the progression of atherosclerosis.
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Affiliation(s)
- Zhaoyu Liu
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Huaiping Zhu
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Xiaoyan Dai
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Cheng Wang
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Ye Ding
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Ping Song
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta
| | - Ming-Hui Zou
- From the Center for Molecular and Translational Medicine, Georgia State University, Atlanta.
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Boshuizen MCS, Hoeksema MA, Neele AE, van der Velden S, Hamers AAJ, Van den Bossche J, Lutgens E, de Winther MPJ. Interferon-β promotes macrophage foam cell formation by altering both cholesterol influx and efflux mechanisms. Cytokine 2015; 77:220-6. [PMID: 26427927 DOI: 10.1016/j.cyto.2015.09.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 09/21/2015] [Accepted: 09/23/2015] [Indexed: 01/25/2023]
Abstract
Foam cell formation is a crucial event in atherogenesis. While interferon-β (IFNβ) is known to promote atherosclerosis in mice, studies on the role of IFNβ on foam cell formation are minimal and conflicting. We therefore extended these studies using both in vitro and in vivo approaches and examined IFNβ's function in macrophage foam cell formation. To do so, murine bone marrow-derived macrophages (BMDMs) and human monocyte-derived macrophages were loaded with acLDL overnight, followed by 6h IFNβ co-treatment. This increased lipid content as measured by Oil red O staining. We next analyzed the lipid uptake pathways of IFNβ-stimulated BMDMs and observed increased endocytosis of DiI-acLDL as compared to controls. These effects were mediated via SR-A, as its gene expression was increased and inhibition of SR-A with Poly(I) blocked the IFNβ-induced increase in Oil red O staining and DiI-acLDL endocytosis. The IFNβ-induced increase in lipid content was also associated with decreased ApoA1-mediated cholesterol efflux, in response to decreased ABCA1 protein and gene expression. To validate our findings in vivo, LDLR(-/-) mice were put on chow or a high cholesterol diet for 10weeks. 24 and 8h before sacrifice mice were injected with IFNβ or PBS, after which thioglycollate-elicited peritoneal macrophages were collected and analyzed. In accordance with the in vitro data, IFNβ increased lipid accumulation. In conclusion, our experimental data support the pro-atherogenic role of IFNβ, as we show that IFNβ promotes macrophage foam cell formation by increasing SR-A-mediated cholesterol influx and decreasing ABCA1-mediated efflux mechanisms.
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Affiliation(s)
- Marieke C S Boshuizen
- Experimental Vascular Biology, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Marten A Hoeksema
- Experimental Vascular Biology, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Annette E Neele
- Experimental Vascular Biology, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Saskia van der Velden
- Experimental Vascular Biology, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Anouk A J Hamers
- Experimental Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jan Van den Bossche
- Experimental Vascular Biology, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Esther Lutgens
- Experimental Vascular Biology, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Institute for Cardiovascular Prevention (IPEK), Ludwig Maximilians University, Munich, Germany
| | - Menno P J de Winther
- Experimental Vascular Biology, Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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Doyle HA, Yang ML, Raycroft MT, Gee RJ, Mamula MJ. Autoantigens: novel forms and presentation to the immune system. Autoimmunity 2013; 47:220-33. [PMID: 24191689 DOI: 10.3109/08916934.2013.850495] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
It is clear that lupus autoimmunity is marked by a variety of abnormalities, including those found at a macroscopic scale, cells and tissues, as well as more microenvironmental influences, originating at the individual cell surface through to the nucleus. The convergence of genetic, epigenetic, and perhaps environmental influences all lead to the overt clinical expression of disease, reflected by the presences of autoantibodies and tissue pathology. This review will address several specific areas that fall among the non-genetic factors that contribute to lupus autoimmunity and related syndromes. In particular, we will discuss the importance of understanding various protein post-translational modifications (PTMs), mechanisms that mediate the ability of "modified self" to trigger autoimmunity, and how these PTMs influence lupus diagnosis. Finally, we will discuss altered pathways of autoantigen presentation that may contribute to the perpetuation of chronic autoimmune disease.
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Affiliation(s)
- Hester A Doyle
- Section of Rheumatology, Department of Internal Medicine, Yale University School of Medicine , New Haven, CT , USA
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Segers FM, den Adel B, Bot I, van der Graaf LM, van der Veer EP, Gonzalez W, Raynal I, de Winther M, Wodzig WK, Poelmann RE, van Berkel TJ, van der Weerd L, Biessen EA. Scavenger Receptor-AI–Targeted Iron Oxide Nanoparticles for In Vivo MRI Detection of Atherosclerotic Lesions. Arterioscler Thromb Vasc Biol 2013; 33:1812-9. [DOI: 10.1161/atvbaha.112.300707] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Filip M.E. Segers
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Brigit den Adel
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Ilze Bot
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Linda M. van der Graaf
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Eric P. van der Veer
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Walter Gonzalez
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Isabelle Raynal
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Menno de Winther
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Will K. Wodzig
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Robert E. Poelmann
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Theo J.C. van Berkel
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Louise van der Weerd
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
| | - Erik A.L. Biessen
- From the Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, Leiden, The Netherlands (F.M.E.S., I.B., E.P.v.d.V., T.J.C.v.B., E.A.L.B.); Department of Anatomy and Embryology (B.d.A., L.M.v.d.G., R.E.P., L.v.d.W.), Department of Radiology (L.v.d.W.), and Department of Human Genetics (L.v.d.W.), Leiden University Medical Center, Leiden, The Netherlands; Department of Research, Guerbet Group, Aulnay-sous-Bois, France (W.G., I.R.); Department of Medical
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Goyal T, Mitra S, Khaidakov M, Wang X, Singla S, Ding Z, Liu S, Mehta JL. Current Concepts of the Role of Oxidized LDL Receptors in Atherosclerosis. Curr Atheroscler Rep 2012; 14:150-159. [PMID: 22286193 DOI: 10.1007/s11883-012-0228-1] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Atherosclerosis is characterized by accumulation of lipids and inflammatory cells in the arterial wall. Oxidized low-density lipoprotein (ox-LDL) plays important role in the genesis and progression of atheromatous plaque. Various scavenger receptors have been recognized in the past two decades that mediate uptake of ox-LDL leading to formation of foam cells. Inhibition of scavenger receptor A and CD36 has been shown to affect progression of atherosclerosis by decreasing foam cell formation. Lectin-type oxidized LDL receptor 1 (LOX-1) participates at various steps involved in the pathogenesis of atherosclerosis, and in experimental studies its blockade has been shown to affect the progression of atherosclerosis at multiple levels. In this review, we summarize the role of ox-LDL and scavenger receptors in the formation of atheroma with emphasis on effects of LOX-1 blockade.
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Affiliation(s)
- Tanu Goyal
- University of Arkansas for Medical Sciences and Central Arkansas Veterans Health System, Little Rock, AR, USA,
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Durst R, Neumark Y, Meiner V, Friedlander Y, Sharon N, Polak A, Beeri R, Danenberg H, Erez G, Spitzen S, Ben-Avi L, Leitersdorf E, Lotan C. Increased Risk for Atherosclerosis of Various Macrophage Scavenger Receptor 1 Alleles. Genet Test Mol Biomarkers 2009; 13:583-7. [DOI: 10.1089/gtmb.2009.0048] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Ronen Durst
- Department of Cardiology, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Yehuda Neumark
- Braun School of Public Health and Community Medicine, Hebrew University–Hadassah, Jerusalem, Israel
| | - Vardiella Meiner
- Department of Human Genetics, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Yechiel Friedlander
- Department of Human Genetics, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Nir Sharon
- Department of Human Genetics, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Arthur Polak
- Department of Cardiology, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Ronen Beeri
- Department of Cardiology, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Haim Danenberg
- Department of Cardiology, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Gilli Erez
- Department of Medicine B, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Shoshi Spitzen
- Department of Medicine B, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Liat Ben-Avi
- Department of Medicine B, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Eran Leitersdorf
- Department of Medicine B, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - Chaim Lotan
- Department of Cardiology, Hadassah Hebrew University Medical Center, Jerusalem, Israel
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Leyva FJ, Pershouse MA, Holian A. Modified low density lipoproteins binding requires a lysine cluster region in the murine macrophage scavenger receptor class A type II. Mol Biol Rep 2009; 37:2847-52. [PMID: 19774489 DOI: 10.1007/s11033-009-9837-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 02/03/2009] [Indexed: 11/26/2022]
Abstract
Atherosclerosis is a consequence of lipid deposition and foam cell formation in the arterial wall. Macrophage scavenger receptor A II is involved in the uptake of modified low density lipoproteins. It contains an extracellular conserved lysine cluster which has been proposed to form a positively charged groove that interacts with acetylated low density lipoproteins (AcLDL). This study evaluated the role of the murine SRA-II and a lysine mutated SRA-II on AcLDL uptake. Fluorescence labeled AcLDL uptake was quantified using a Laser Scan Cytometer. A significant increase in fluorescence uptake was found in the cells transfected with SRA-II versus those with empty vector. Cells expressing the lysine mutated SRA-II also demonstrated a significant decrease in their uptake of AcLDL. This data supports the concept that the conserved lysine cluster in murine SRA-II is the binding region for AcLDL or contributes to the trimeric structure of SRA-II necessary for AcLDL binding.
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Affiliation(s)
- Francisco J Leyva
- Experimental Atherosclerosis Section, Translational Medicine, National Heart, Lung, and Blood Institute, National Institutes of Health, 10 Center Drive, Building 10, Room 5N-111, Bethesda, MD 20892-1422, USA.
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9
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Leyva FJ, Pershouse MA. Quantitative and qualitative methods using fluorescence microscopy for the study of modified low density lipoproteins uptake. SCANNING 2009; 31:167-173. [PMID: 19768737 PMCID: PMC4068399 DOI: 10.1002/sca.20155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Atherosclerosis and heart disease are the main cause of death in United States. The development of atherosclerosis includes lipid deposition and foam cell formation in the artery wall. Scavenger Receptors A-I and II (SRA-I/II) have an important role of in foam cell formation and atherogenesis. Most of the SRA-I/II studies had been performed using Iodine-125-radiolabeled modified low-density lipoprotein. This report attempts to validate the use of fluorescence microscopy techniques as an alternative to obtain qualitative and quantitative information of the uptake of fluorescence-labeled acetylated low-density lipoprotein (AcLDL) in adherent CHO cells expressing SRA-I/II. After verifying the protein expression of SRA-I and II, uptake was quantified using a Laser Scan Cytometer, and images of cells containing fluorescent AcLDL were obtained. A significant increase in fluorescence was found in the cells transfected with SRA-I/II vs. those with empty vector. When SRA-I/II competitive ligands were used, the uptake of AcLDL was significantly decreased. In conclusion, the use of fluorescence microscopy techniques in obtaining qualitative and quantitative information of the uptake of fluorescence-labeled AcLDL by adherent cells, such as CHO cells, is an alternative to the traditional use of radiolabeled iodine.
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Affiliation(s)
- Francisco J Leyva
- Division of Lung Diseases, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.
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10
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Ohwaki K, Bujo H, Jiang M, Yamazaki H, Schneider WJ, Saito Y. A Secreted Soluble Form of LR11, Specifically Expressed in Intimal Smooth Muscle Cells, Accelerates Formation of Lipid-Laden Macrophages. Arterioscler Thromb Vasc Biol 2007; 27:1050-6. [PMID: 17332490 DOI: 10.1161/atvbaha.106.137091] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE Macrophages play a key role in lipid-rich unstable plaque formation and interact with intimal smooth muscle cells (SMCs) in early and progressive stages of atherosclerosis. LR11 (also called sorLA), a member of low-density lipoprotein receptor family, is highly and specifically expressed in intimal SMCs, and causes urokinase-type plasminogen activator receptor-mediated degradation of extracellular matrices. Here we investigated whether the secreted soluble form of LR11 (solLR11) enhances adhesion, migration, and lipid accumulation in macrophages using animal models and cultured systems. METHODS AND RESULTS Immunohistochemistry showed solLR11 expression in thickened intima of balloon-denuded rat artery. Macrophage infiltration into the cuff-injured artery was markedly reduced in LR11-deficient mice. In vitro functional assays using THP-1-derived macrophages showed that solLR11 (1 microg/mL) significantly increased acetylated low-density lipoprotein uptake by THP-1 cells and cell surface levels of scavenger receptor SR-A 1.7- and 2.8-fold, respectively. SolLR11 dose-dependently increased the migration activity of THP-1 macrophages and adhesion to extracellular matrices 2.0- and 2.1-fold, respectively, at 1 microg/mL. These effects of solLR11 were almost completely inhibited by a neutralizing anti-urokinase-type plasminogen activator receptor antibody. CONCLUSION SolLR11, secreted from intimal SMCs, regulates adhesion, migration, and lipid accumulation in macrophages through activation of urokinase-type plasminogen activator receptor. The formation of lipid-laden macrophages in atherosclerotic plaques possibly is regulated by SolLR11 of intimal SMCs.
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MESH Headings
- Animals
- Blotting, Western
- Carotid Artery Injuries/metabolism
- Carotid Artery Injuries/pathology
- Carotid Artery, Common/metabolism
- Carotid Artery, Common/pathology
- Cell Adhesion/physiology
- Cell Movement
- Cells, Cultured
- Humans
- Immunohistochemistry
- Lipoproteins, LDL/metabolism
- Macrophages/cytology
- Macrophages/metabolism
- Male
- Membrane Transport Proteins/biosynthesis
- Mice
- Mice, Knockout
- Microscopy, Fluorescence
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Nerve Tissue Proteins
- Rats
- Rats, Wistar
- Receptors, LDL/biosynthesis
- Tunica Intima/metabolism
- Tunica Intima/pathology
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Affiliation(s)
- Kenji Ohwaki
- Department of Clinical Cell Biology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan
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11
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Ghesquiere SAI, Gijbels MJJ, Anthonsen M, van Gorp PJJ, van der Made I, Johansen B, Hofker MH, de Winther MPJ. Macrophage-specific overexpression of group IIa sPLA2 increases atherosclerosis and enhances collagen deposition. J Lipid Res 2005; 46:201-10. [PMID: 15576846 DOI: 10.1194/jlr.m400253-jlr200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Atherosclerosis is a chronic inflammatory disease of the vessel wall characterized by the accumulation of lipid-laden macrophages and fibrotic material. The initiation of the disease is accompanied by the accumulation of modified lipoproteins in the vessel wall. Group IIa secretory phospholipase A2 (sPLA2 IIa) is a key candidate player in the enzymatic modification of low density lipoproteins. To study the role of sPLA2 IIa in macrophages during atherogenesis, transgenic mice were generated using the human sPLA2 IIa gene and the CD11b promoter. Bone marrow transplantation to LDL receptor-deficient mice was performed to study sPLA2 IIa in atherosclerosis. After 10 weeks of high-fat diet, mice overexpressing sPLA2 IIa in macrophages showed 2.3-fold larger lesions compared with control mice. Pathological examination revealed that sPLA2 IIa-expressing mice had increased collagen in their lesions, independent of lesion size. However, smooth muscle cells or fibroblasts in the lesions were not affected. Other parameters studied, including T-cells and cell turnover, were not significantly affected by overexpression of sPLA2 IIa in macrophages. These data clearly show that macrophage sPLA2 IIa is a proatherogenic factor and suggest that the enzyme regulates collagen production in the plaque and thus fibrotic cap development.
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Affiliation(s)
- Stijn A I Ghesquiere
- Department of Molecular Genetics, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands
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12
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Furman C, Copin C, Kandoussi M, Davidson R, Moreau M, McTaggiart F, Chapman MJ, Fruchart JC, Rouis M. Rosuvastatin reduces MMP-7 secretion by human monocyte-derived macrophages: potential relevance to atherosclerotic plaque stability. Atherosclerosis 2004; 174:93-8. [PMID: 15135256 DOI: 10.1016/j.atherosclerosis.2004.01.009] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2003] [Accepted: 01/22/2004] [Indexed: 11/25/2022]
Abstract
3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have been shown to reduce cardiovascular morbidity and mortality by their actions on atherogenic lipid profiles and by pleiotropic effects. In this study, we have investigated the effect of a new statin, rosuvastatin (Crestor), on sterol synthesis and the expression of metalloproteinases (MMPs) in human monocyte-derived macrophages (HMDM). Rosuvastatin dose-dependently inhibited sterol synthesis from acetate with an IC(50) of 70 nM. In addition, MMP-7 levels were reduced in a dose-dependent manner with maximal inhibition of 50% (P < 0.01) at 1 microM. Also, addition of isoprenoids such as farnesyl pyrophosphate (Fpp) or geranylgeranyl pyrophosphate (GGpp) fully overcame the inhibitory effect of rosuvastatin on MMP-7. Neither quantitative PCR nor transient transfection of HMDM with a luciferase reporter construct under the control of human MMP-7 promoter (2300 bp of the 5' region on MMP-7 gene) showed a decrease in MMP-7 mRNA following treatment with rosuvastatin (10(-6)M). However, the inhibitory effect of the statin occurred at the post-transcriptional level as determined by actinomycin D experiment. In conclusion, several studies have reported a high expression of active MMP-7 in human atherosclerotic plaques indicating a potential role in the weakening of the fibrous cap, predisposing it to rupture. The effect of rosuvastatin in reducing MMP-7 might protect fibrous caps from degradation and in turn stabilize atheromatous plaques.
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Affiliation(s)
- Christophe Furman
- INSERM U-545 and Institut Pasteur de Lille, 1 rue du Professeur Calmette, BP 245, 59019 Lille Cedex, France
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13
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Platt N, Haworth R, Darley L, Gordon S. The many roles of the class A macrophage scavenger receptor. INTERNATIONAL REVIEW OF CYTOLOGY 2002; 212:1-40. [PMID: 11804035 DOI: 10.1016/s0074-7696(01)12002-4] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The class A macrophage scavenger receptor (SR-A) is the prototypic example of a group of plasma membrane receptors collectively known as scavenger receptors. SR-A displays the ability to bind and endocytose large quantities of modified lipoprotein. Hence, it is thought to be one of the main receptors involved in mediating lipid influx into macrophages (Mphi), which promotes their conversion into foam cells that are abundant in the atherosclerotic lesion. However, as a result of increased interest and research effort and through the development of specific reagents and animal models, it is now appreciated to be multifunctional. These roles include Mphi growth and maintenance, adhesion to the substratum, cell-cell interactions, phagocytosis, and host defense. In this review, we attempt to summarize the evidence and argue that these kinds of activities underlie the biological versatility of Mphi.
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Affiliation(s)
- Nick Platt
- Sir William Dunn School of Pathology, University of Oxford, United Kingdom
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14
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Abstract
The scope of this review is to discuss the new advances in our understanding of the role of scavenger receptor class A in the initiation and modulation of the atherosclerotic process. Through the approaches of gene manipulation in the mouse model, a substantial body of literature has accumulated that depicts scavenger receptor class A as a central player in atherogenesis. In studies of scavenger receptor class A overexpression in macrophages through bone marrow transplantation using transgenic donor material, recipient mice with hyperlipidemia caused either by apolipoprotein E or LDL receptor deficiency did not show convincing changes in the degree of atherosclerosis development compared with controls. Conversely, the deletion of the scavenger receptor class A gene in the mouse has shown, in a consistent and significant fashion, that this receptor serves a pro-atherogenic function under hyperlipidemic conditions, as both apolipoprotein E and LDL receptor-deficient mice had reduced atherosclerosis in the absence of scavenger receptor class A. In addition, we have recently shown that C57BL/6 mice are protected from diet-induced atherosclerosis when they lack scavenger receptor class A, and that the macrophage is the cell type responsible for the effect of scavenger receptor class A deficiency in reducing lesion formation in C57BL/6 and LDL receptor null mice. Together, these results demonstrate that macrophage scavenger receptor class A contributes significantly to atherosclerotic lesion formation, and suggest that the uptake of oxidized or modified lipoproteins by vessel wall macrophages is a central process in atherogenesis.
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Affiliation(s)
- M F Linton
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
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15
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Heider H, Wintergerst ES. Mimicking phosphorylation at Ser-48 strongly reduces surface expression of human macrophage scavenger receptor class A: implications on cell motility. FEBS Lett 2001; 505:185-90. [PMID: 11557066 DOI: 10.1016/s0014-5793(01)02819-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The role of human macrophage scavenger receptor A1 (SRA1) in the development of atherosclerotic lesions is still scarcely defined. Substituting serine 48 in human SRA1 by an aspartate demonstrated that (1) surface expression of the mutated receptor was 13-fold decreased; (2) the amount of cell-associated Texas red-labeled acetylated low density lipoprotein (LDL) in mutant receptor-expressing cells was almost three-fold reduced; (3) the migration of mutant receptor-transfected cells towards surfaces coated with oxidized LDL decreased by almost 60% compared to cells that were transfected with the wild type receptor. Phosphorylation of the cytoplasmic part of SRA1 may help to modulate the residence time of macrophages in atherosclerotic lesions.
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Affiliation(s)
- H Heider
- Institute of Biochemistry, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland.
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16
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Abstract
Genetically engineered animal models have been and will continue to be invaluable for exploring the basic mechanisms involved in the aging process as well as in extending our understanding of diseases found to be more prevalent in the older human population. Continued development of such in vivo systems will allow scientists to further dissect the role genetic and environmental factors play in aging and in age-related disease states and to enhance our understanding of these processes. In this article we discuss techniques involved in the development of such models and review some examples of laboratory mouse strains that have been used to study either normal aging or select diseases associated with aging.
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Affiliation(s)
- J K Andersen
- Buck Institute for Age Research, 8001 Redwood Boulevard, Novato, CA 94945, USA.
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17
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Gough PJ, Gordon S, Greaves DR. The use of human CD68 transcriptional regulatory sequences to direct high-level expression of class A scavenger receptor in macrophages in vitro and in vivo. Immunology 2001; 103:351-61. [PMID: 11454064 PMCID: PMC1783239 DOI: 10.1046/j.1365-2567.2001.01256.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Macrophages (Mphi) play a key role in innate and acquired immunity. The study of Mphi biology has been hampered by the absence of suitable gene regulatory sequences for the overexpression of heterologous genes in Mphi. The human CD68 gene encodes a glycoprotein that is expressed in monocytes and Mphi, and therefore represents an attractive candidate gene for the generation of a Mphi-specific gene-targeting vector. A transgene expression cassette that combines 2.9 kb of CD68 5' flanking sequence with the 83-bp first intron (IVS-1) of the CD68 gene, directed high-level, long-lasting expression of class A human scavenger receptor (hSR-A) isoforms in the murine Mphi cell line, RAW-264. By using this CD68 expression cassette to generate Mphi cell lines that overexpress a soluble secreted form of the extracellular portion of type I human SR-A, we were able to purify significant quantities of this protein and show its ability to inhibit SR-A-mediated endocytosis. Analysis of two independent lines of transgenic mice that expressed type III human SR-A under the control of the CD68 gene sequences revealed transgene mRNA expression in elicited Mphi populations and in mouse tissues in a pattern that was consistent with Mphi-specific gene targeting. These data show that CD68 transcriptional regulatory sequences can be used to direct high-level transgene expression in Mphi in vitro and in vivo.
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Affiliation(s)
- P J Gough
- Sir William Dunn School of Pathology, University of Oxford, Oxford, UK
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18
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Abstract
In 1993, several groups, working independently, reported the successful generation of transgenic mice with yeast artificial chromosomes (YACs) using standard techniques. The transfer of these large fragments of cloned genomic DNA correlated with optimal expression levels of the transgenes, irrespective of their location in the host genome. Thereafter, other groups confirmed the advantages of YAC transgenesis and position-independent and copy number-dependent transgene expression were demonstrated in most cases. The transfer of YACs to the germ line of mice has become popular in many transgenic facilities to guarantee faithful expression of transgenes. This technique was rapidly exported to livestock and soon transgenic rabbits, pigs and other mammals were produced with YACs. Transgenic animals were also produced with bacterial or P1-derived artificial chromosomes (BACs/PACs) with similar success. The use of YACs, BACs and PACs in transgenesis has allowed the discovery of new genes by complementation of mutations, the identification of key regulatory sequences within genomic loci that are crucial for the proper expression of genes and the design of improved animal models of human genetic diseases. Transgenesis with artificial chromosomes has proven useful in a variety of biological, medical and biotechnological applications and is considered a major breakthrough in the generation of transgenic animals. In this report, we will review the recent history of YAC/BAC/PAC-transgenic animals indicating their benefits and the potential problems associated with them. In this new era of genomics, the generation and analysis of transgenic animals carrying artificial chromosome-type transgenes will be fundamental to functionally identify and understand the role of new genes, included within large pieces of genomes, by direct complementation of mutations or by observation of their phenotypic consequences.
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Affiliation(s)
- P Giraldo
- Department of Molecular and Cellular Biology, Centro Nacional de Biotecnología, Madrid, Spain
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19
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Van Eck M, De Winther MP, Herijgers N, Havekes LM, Hofker MH, Groot PH, Van Berkel TJ. Effect of human scavenger receptor class A overexpression in bone marrow-derived cells on cholesterol levels and atherosclerosis in ApoE-deficient mice. Arterioscler Thromb Vasc Biol 2000; 20:2600-6. [PMID: 11116059 DOI: 10.1161/01.atv.20.12.2600] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In the arterial wall, scavenger receptor class A (SRA) is implicated in pathological lipid deposition. In contrast, in the liver, SRA is suggested to remove modified lipoproteins from the circulation, thereby protecting the body from their pathological action. The role of SRA on bone marrow-derived cells in lipid metabolism and atherogenesis was assessed in vivo by transplantation of bone marrow cells overexpressing human SRA (MSR1) to apoE-deficient mice. In vitro studies with peritoneal macrophages from the transplanted mice showed that macrophage scavenger receptor function, as measured by cell association and degradation studies with acetylated LDL, was approximately 3-fold increased on overexpression of MSR1 in bone marrow-derived cells as compared with control mice. Despite the increased macrophage scavenger receptor function in vitro, no significant effect of MSR1 overexpression in bone marrow-derived cells on the in vivo atherosclerotic lesion development was found. In addition to arterial wall macrophages, liver sinusoidal Kupffer cells also overexpress MSR1 after bone marrow transplantation, which may scavenge atherogenic particles more efficiently from the blood compartment. Introduction of bone marrow cells overexpressing human MSR1 in apoE-deficient mice induced a significant reduction in serum cholesterol levels of approximately 20% (P:<0.001, 2-way ANOVA) as the result of a decrease in VLDL cholesterol. It is suggested that the reduction in VLDL cholesterol levels is due to increased clearance of modified lipoproteins by the overexpressed MSR1 in Kupffer cells of the liver, thereby protecting the arterial wall against the proatherogenic action of modified lipoproteins.
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MESH Headings
- Animals
- Aorta/pathology
- Apolipoproteins E/deficiency
- Apolipoproteins E/genetics
- Arteriosclerosis/blood
- Arteriosclerosis/etiology
- Arteriosclerosis/genetics
- Bone Marrow Cells/metabolism
- Bone Marrow Transplantation
- Cells, Cultured
- Cholesterol, VLDL/blood
- Female
- Humans
- Kupffer Cells/metabolism
- Lipid Metabolism
- Lipoproteins, LDL/metabolism
- Macrophages, Peritoneal/metabolism
- Membrane Proteins
- Mice
- Mice, Knockout
- Mice, Transgenic
- Myocardium/pathology
- Receptors, Immunologic/biosynthesis
- Receptors, Immunologic/genetics
- Receptors, Lipoprotein
- Receptors, Scavenger
- Scavenger Receptors, Class A
- Scavenger Receptors, Class B
- Triglycerides/blood
- Whole-Body Irradiation
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Affiliation(s)
- M Van Eck
- Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University Medical Center, Sylvius Laboratories, Leiden University (The Netherlands).
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20
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Herijgers N, de Winther MP, Van Eck M, Havekes LM, Hofker MH, Hoogerbrugge PM, Van Berkel TJ. Effect of human scavenger receptor class A overexpression in bone marrow-derived cells on lipoprotein metabolism and atherosclerosis in low density lipoprotein receptor knockout mice. J Lipid Res 2000. [DOI: 10.1016/s0022-2275(20)33452-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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21
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de Winther MP, van Dijk KW, Havekes LM, Hofker MH. Macrophage scavenger receptor class A: A multifunctional receptor in atherosclerosis. Arterioscler Thromb Vasc Biol 2000; 20:290-7. [PMID: 10669623 DOI: 10.1161/01.atv.20.2.290] [Citation(s) in RCA: 184] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In atherogenesis, elevated plasma levels of low density lipoprotein (LDL) lead to the chronic presence of LDL in the arterial wall. There, LDL is modified (eg, oxidized), and these modified lipoproteins activate endothelial cells, which attract circulating monocytes. These monocytes enter the vessel wall, differentiate into macrophages, and subject the modified lipoproteins to endocytosis through scavenger receptor pathways. This unrestricted uptake, which is not limited by intracellular cholesterol levels, eventually leads to the formation of lipid-filled foam cells, the initial step in atherosclerosis. Macrophage scavenger receptor class A (SRA) is thought to be one of the main receptors involved in foam cell formation, mediating the influx of lipids into the macrophages. In addition to this role in modified lipoprotein uptake by macrophages, the SRA has been shown to be important in the inflammatory response in host defense, cellular activation, adhesion, and cell-cell interaction. Given the importance of these processes in atherogenesis, these latter functions may prove to make the SRA a multifunctional player in the atherosclerotic process.
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Affiliation(s)
- M P de Winther
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands.
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