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Kiriakidis S, Henze A, Kruszynska‐Ziaja I, Skobridis K, Theodorou V, Paleolog EM, Mazzone M. Factor‐inhibiting HIF‐1 (FIH‐1) is required for human vascular endothelial cell survival. FASEB J 2015; 29:2814-27. [DOI: 10.1096/fj.14-252379] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 03/06/2015] [Indexed: 01/22/2023]
Affiliation(s)
- Serafim Kiriakidis
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal SciencesKennedy Institute of Rheumatology, University of OxfordUnited Kingdom
| | - Anne‐Theres Henze
- Laboratory of Molecular Oncology and Angiogenesis, Vesalius Research Center, Vlaams Instituut voor Biotechnologie (VIB)LeuvenBelgium
- Laboratory of Molecular Oncology and Angiogenesis, Vesalius Research CenterDepartment of OncologyKatholieke Universiteit (KU)LeuvenBelgium
| | - Ilona Kruszynska‐Ziaja
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal SciencesKennedy Institute of Rheumatology, University of OxfordUnited Kingdom
| | - Konstantinos Skobridis
- Department of ChemistrySection of Organic Chemistry and BiochemistryUniversity of IoanninaGreece
| | - Vassiliki Theodorou
- Department of ChemistrySection of Organic Chemistry and BiochemistryUniversity of IoanninaGreece
| | - Ewa M. Paleolog
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal SciencesKennedy Institute of Rheumatology, University of OxfordUnited Kingdom
| | - Massimiliano Mazzone
- Laboratory of Molecular Oncology and Angiogenesis, Vesalius Research Center, Vlaams Instituut voor Biotechnologie (VIB)LeuvenBelgium
- Laboratory of Molecular Oncology and Angiogenesis, Vesalius Research CenterDepartment of OncologyKatholieke Universiteit (KU)LeuvenBelgium
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Khong TL, Thairu N, Larsen H, Dawson PM, Kiriakidis S, Paleolog EM. Identification of the angiogenic gene signature induced by EGF and hypoxia in colorectal cancer. BMC Cancer 2013; 13:518. [PMID: 24180698 PMCID: PMC4228238 DOI: 10.1186/1471-2407-13-518] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 10/23/2013] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Colorectal cancer (CRC) is characterised by hypoxia, which activates gene transcription through hypoxia-inducible factors (HIF), as well as by expression of epidermal growth factor (EGF) and EGF receptors, targeting of which has been demonstrated to provide therapeutic benefit in CRC. Although EGF has been demonstrated to induce expression of angiogenic mediators, potential interactions in CRC between EGF-mediated signalling and the hypoxia/HIF pathway remain uncharacterised. METHODS PCR-based profiling was applied to identify angiogenic genes in Caco-2 CRC cells regulated by hypoxia, the hypoxia mimetic dimethyloxallylglycine (DMOG) and/or EGF. Western blotting was used to determine the role of HIF-1alpha, HIF-2alpha and MAPK cell signalling in mediating the angiogenic responses. RESULTS We identified a total of 9 angiogenic genes, including angiopoietin-like (ANGPTL) 4, ephrin (EFNA) 3, transforming growth factor (TGF) β1 and vascular endothelial growth factor (VEGF), to be upregulated in a HIF dependent manner in Caco-2 CRC cells in response to both hypoxia and the hypoxia mimetic dimethyloxallylglycine (DMOG). Stimulation with EGF resulted in EGFR tyrosine autophosphorylation, activation of p42/p44 MAP kinases and stabilisation of HIF-1α and HIF-2α proteins. However, expression of 84 angiogenic genes remained unchanged in response to EGF alone. Crucially, addition of DMOG in combination with EGF significantly increased expression of a further 11 genes (in addition to the 9 genes upregulated in response to either DMOG alone or hypoxia alone). These additional genes included chemokines (CCL-11/eotaxin-1 and interleukin-8), collagen type IV α3 chain, integrin β3 chain, TGFα and VEGF receptor KDR. CONCLUSION These findings suggest that although EGFR phosphorylation activates the MAP kinase signalling and promotes HIF stabilisation in CRC, this alone is not sufficient to induce angiogenic gene expression. In contrast, HIF activation downstream of hypoxia/DMOG drives expression of genes such as ANGPTL4, EFNA3, TGFβ1 and VEGF. Finally, HIF activation synergises with EGF-mediated signalling to additionally induce a unique sub-group of candidate angiogenic genes. Our data highlight the complex interrelationship between tumour hypoxia, EGF and angiogenesis in the pathogenesis of CRC.
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Affiliation(s)
| | | | | | | | | | - Ewa M Paleolog
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College, London, UK.
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Lim CS, Kiriakidis S, Sandison A, Paleolog EM, Davies AH. Hypoxia-inducible factor pathway and diseases of the vascular wall. J Vasc Surg 2013; 58:219-30. [PMID: 23643279 DOI: 10.1016/j.jvs.2013.02.240] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Revised: 02/11/2013] [Accepted: 02/16/2013] [Indexed: 01/01/2023]
Abstract
BACKGROUND Hypoxia may contribute to the pathogenesis of various diseases of the vascular wall. Hypoxia-inducible factors (HIFs) are nuclear transcriptional factors that regulate the transcription of genes that mediate cellular and tissue homeostatic responses to altered oxygenation. This article reviews the published literature on and discusses the role of the HIF pathway in diseases involving the vascular wall, including atherosclerosis, arterial aneurysms, pulmonary hypertension, vascular graft failure, chronic venous diseases, and vascular malformation. METHODS PubMed was searched with the terms "hypoxia-inducible factor" or "HIF" and "atherosclerosis," "carotid stenosis," "aneurysm," "pulmonary artery hypertension," "varicose veins," "venous thrombosis," "graft thrombosis," and "vascular malformation." RESULTS In atherosclerotic plaque, HIF-1α was localized in macrophages and smooth muscle cells bordering the necrotic core. Increased HIF-1α may contribute to atherosclerosis through alteration of smooth muscle cell proliferation and migration, angiogenesis, and lipid metabolism. The expression of HIF-1α is significantly elevated in aortic aneurysms compared with nonaneurysmal arteries. In pulmonary hypertension, HIF-1α contributes to the increase of intracellular K(+) and Ca(2+) leading to vasoconstriction of pulmonary smooth muscle cells. Alteration of the HIF pathway may contribute to vascular graft failure through the formation of intimal hyperplasia. In chronic venous disease, HIF pathway dysregulation contributes to formation of varicose veins and venous thromboembolism. However, whether the activation of the HIF pathway is protective or destructive to the venous wall is unclear. Increased activation of the HIF pathway causes aberrant expression of angiogenic factors contributing to the formation and maintenance of vascular malformations. CONCLUSIONS Pathologic vascular wall remodelling of many common diseases of the blood vessels has been found to be associated with altered activity of the HIF pathway. Therefore, understanding the role of the HIF pathway in diseases of the vascular wall is important to identify novel therapeutic strategies in the management of these pathologies.
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Affiliation(s)
- Chung S Lim
- Academic Section of Vascular Surgery, Department of Surgery and Cancer, Faculty of Medicine, Charing Cross Hospital Campus, Imperial College London, London, United Kingdom
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Abstract
The study aimed to investigate the viability of a varicose vein (VV) organ culture model by assessing cell death pattern. To assess pattern of cell death with time, VV organ cultures were incubated for up to 14 days with regular medium changed. To assess viability, cell death of VV organ cultures treated with sodium azide and their untreated counterparts was assayed. Increased cell death was measured in VV organ cultures from day 0 to 2. Cell death decreased gradually after day 2 and plateaued from day 8 to 14.VV organ cultures treated with sodium azide demonstrated significantly more cell death in tissue (P = 0.001). Cell death measured in cultures treated with sodium azide continued to increase until day 7. In conclusion, this study demonstrated the viability of a VV organ culture model with most cell death occurred within the first two days and then declined to a relatively low level.
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Affiliation(s)
- Chung S Lim
- Academic Section of Vascular Surgery, Department of Surgery and Cancer, London, W6 8RF, UK
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Kiriakidis S, Paleolog EM. Vascular endothelium--role in chronic inflammatory disease. Postepy Biochem 2013; 59:415-423. [PMID: 24745172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The vascular endothelial lining of blood vessels plays a key 'target-effector' role in vivo, integrating the body's response to inflammatory cytokines, chemokines and growth factors (derived from both endothelial cells themselves and from other cells such as leukocytes and fibroblasts), to allow leukocyte activation, adhesion and extravasation from the flowing blood into underlying tissue. Endothelial proliferation, through the process of angiogenesis, results in an increased cell surface area for these events to occur, and further functions to deliver oxygen and nutrients, and to remove waste products. In addition to playing an important role in physiology, the endothelium is thus an active participant in inflammatory pathologies. One of the best understood diseases in which inflammation and angiogenesis play a part is rheumatoid arthritis (RA). Blockade of the inflammatory cascade in RA has significant consequences for the vasculature, highlighting the links between reducing endothelial activation and therapeutic benefit in chronic inflammatory disorders.
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Muz B, Larsen H, Madden L, Kiriakidis S, Paleolog EM. Prolyl hydroxylase domain enzyme 2 is the major player in regulating hypoxic responses in rheumatoid arthritis. ACTA ACUST UNITED AC 2012; 64:2856-67. [DOI: 10.1002/art.34479] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Larsen H, Muz B, Khong TL, Feldmann M, Paleolog EM. Differential effects of Th1 versus Th2 cytokines in combination with hypoxia on HIFs and angiogenesis in RA. Arthritis Res Ther 2012; 14:R180. [PMID: 22866899 PMCID: PMC3580575 DOI: 10.1186/ar3934] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 08/06/2012] [Indexed: 11/18/2022] Open
Abstract
Introduction Hypoxia and T-helper cell 1 (Th1) cytokine-driven inflammation are key features of rheumatoid arthritis (RA) and contribute to disease pathogenesis by promoting angiogenesis. The objective of our study was to characterise the angiogenic gene signature of RA fibroblast-like synoviocytes (FLS) in response to hypoxia, as well as Th1 and T-helper cell 2 (Th2) cytokines, and in particular to dissect out effects of combined hypoxia and cytokines on hypoxia inducible transcription factors (HIFs) and angiogenesis. Methods Human angiogenesis PCR arrays were used to screen cDNA from RA FLS exposed to hypoxia (1% oxygen) or dimethyloxalylglycine, which stabilises HIFs. The involvement of HIF isoforms in generating the angiogenic signature of RA FLS stimulated with hypoxia and/or cytokines was investigated using a DNA-binding assay and RNA interference. The angiogenic potential of conditioned media from hypoxia-treated and/or cytokine-treated RA FLS was measured using an in vitro endothelial-based assay. Results Expression of 12 angiogenic genes was significantly altered in RA FLS exposed to hypoxia, and seven of these were changed by dimethyloxalylglycine, including ephrin A3 (EFNA3), vascular endothelial growth factor (VEGF), adipokines angiopoietin-like (ANGPTL)-4 and leptin. These four proangiogenic genes were dependent on HIF-1 in hypoxia to various degrees: EFNA3 >ANGPTL-4 >VEGF >leptin. The Th1 cytokines TNFα and IL-1β induced HIF-1 but not HIF-2 transcription as well as activity, and this effect was additive with hypoxia. In contrast, Th2 cytokines had no effect on HIFs. IL-1β synergised with hypoxia to upregulate EFNA3 and VEGF in a HIF-1-dependent fashion but, despite strongly inducing HIF-1, TNFα suppressed adipokine expression and had minimal effect on EFNA3. Supernatants from RA FLS subjected to hypoxia and TNFα induced fewer endothelial tubules than those from FLS subjected to TNFα or hypoxia alone, despite high VEGF protein levels. The Th2 cytokine IL-4 strongly induced ANGPTL-4 and angiogenesis by normoxic FLS and synergised with hypoxia to induce further proangiogenic activity. Conclusion The present work demonstrates that Th1 cytokines in combination with hypoxia are not sufficient to induce angiogenic activity by RA FLS despite HIF-1 activation and VEGF production. In contrast, Th2 cytokines induce angiogenic activity in normoxia and hypoxia, despite their inability to activate HIFs, highlighting the complex relationships between hypoxia, angiogenesis and inflammation in RA.
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Raatz Y, Ibrahim S, Feldmann M, Paleolog EM. Gene expression profiling and functional analysis of angiogenic markers in murine collagen-induced arthritis. Arthritis Res Ther 2012; 14:R169. [PMID: 22817681 PMCID: PMC3580563 DOI: 10.1186/ar3922] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 07/20/2012] [Indexed: 01/13/2023] Open
Abstract
Introduction Dysregulated angiogenesis is implicated in the pathogenesis of rheumatoid arthritis (RA). To provide a more profound understanding of arthritis-associated angiogenesis, we evaluated the expression of angiogenesis-modulating genes at onset, peak and declining phases of collagen-induced arthritis (CIA), a well-established mouse model for RA. Methods CIA was induced in DBA/1 mice with type II collagen. Functional capillary density in synovial tissue of knee joints was determined by intravital fluorescence microscopy. To assess the ability of arthritic joint homogenates to induce angiogenesis, an endothelial chemotaxis assay and an in vivo matrigel plug assay were employed. The temporal expression profile of angiogenesis-related genes in arthritic paws was analysed by quantitative real-time RT-PCR using an angiogenesis focused array as well as gene specific PCR. Finally, we investigated the therapeutic effect of a monoclonal antibody specifically blocking the binding of VEGF to neuropilin (NRP)-1. Results Although arthritic paw homogenates displayed angiogenic activity in vitro and in vivo, and synovia of arthritic paws appeared highly vascularised on histological examination, the functional capillary density in arthritic knee synovia was significantly decreased, whereas capillary diameter was increased. Of the 84 genes analysed, 41 displayed a differential expression in arthritic paws as compared to control paws. Most significant alterations were seen at the peak of clinical arthritis. Increased mRNA expression could be observed for VEGF receptors (Flt-1, Flk-1, Nrp-1, Nrp-2), as well as for midkine, hepatocyte growth factor, insulin-like growth factor-1 and angiopoietin-1. Signalling through NRP-1 accounted in part for the chemotactic activity for endothelial cells observed in arthritic paw homogenates. Importantly, therapeutic administration of anti-NRP1B antibody significantly reduced disease severity and progression in CIA mice. Conclusions Our findings confirm that the arthritic synovium in murine CIA is a site of active angiogenesis, but an altered balance in the expression of angiogenic factors seems to favour the formation of non-functional and dilated capillaries. Furthermore, our results validate NRP-1 as a key player in the pathogenesis of CIA, and support the VEGF/VEGF receptor pathway as a potential therapeutic target in RA.
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Gompels LL, Malik NM, Madden L, Jin P, Feldmann M, Shepard HM, Paleolog EM. Human epidermal growth factor receptor bispecific ligand trap RB200: abrogation of collagen-induced arthritis in combination with tumour necrosis factor blockade. Arthritis Res Ther 2011; 13:R161. [PMID: 21982514 PMCID: PMC3308094 DOI: 10.1186/ar3480] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 07/29/2011] [Accepted: 10/07/2011] [Indexed: 11/22/2022] Open
Abstract
Introduction Rheumatoid arthritis (RA) is a chronic disease associated with inflammation and destruction of bone and cartilage. Although inhibition of TNFα is widely used to treat RA, a significant number of patients do not respond to TNFα blockade, and therefore there is a compelling need to continue to identify alternative therapeutic strategies for treating chronic inflammatory diseases such as RA. The anti-epidermal growth factor (anti-EGF) receptor antibody trastuzumab has revolutionised the treatment of patients with EGF receptor-positive breast cancer. Expression of EGF ligands and receptors (known as HER) has also been documented in RA. The highly unique compound RB200 is a bispecific ligand trap that is composed of full-length extracellular domains of HER1 and HER3 EGF receptors. Because of its pan-HER specificity, RB200 inhibits responses mediated by HER1, HER2 and HER3 in vitro and in vivo. The objective of this study was to assess the effect of RB200 combined with TNF blockade in a murine collagen-induced arthritis (CIA) model of RA. Methods Arthritic mice were treated with RB200 alone or in combination with the TNF receptor fusion protein etanercept. We performed immunohistochemistry to assess CD31 and in vivo fluorescent imaging using anti-E-selectin antibody labelled with fluorescent dye to elucidate the effect of RB200 on the vasculature in CIA. Results RB200 significantly abrogated CIA by reducing paw swelling and clinical scores. Importantly, low-dose RB200 combined with a suboptimal dose of etanercept led to complete abrogation of arthritis. Moreover, the combination of RB200 with etanercept abrogated the intensity of the E-selectin-targeted signal to the level seen in control animals not immunised to CIA. Conclusions The human pan-EGF receptor bispecific ligand trap RB200, when combined with low-dose etanercept, abrogates CIA, suggesting that inhibition of events downstream of EGF receptor activation, in combination with TNFα inhibitors, may hold promise as a future therapy for patients with RA.
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Affiliation(s)
- Luke L Gompels
- Faculty of Medicine, Kennedy Institute of Rheumatology, 65 Aspenlea Road, London, W6 8LH, Imperial College London, London, UK
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Akhavani MA, Paleolog EM, Kang N. Muscle hypoxia in rheumatoid hands: does it play a role in ulnar drift? J Hand Surg Am 2011; 36:677-85. [PMID: 21463729 DOI: 10.1016/j.jhsa.2011.01.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 01/23/2011] [Accepted: 01/24/2011] [Indexed: 02/02/2023]
Abstract
PURPOSE The cause of ulnar drift in patients with rheumatoid arthritis (RA) is unknown. It may occur because of external forces applied to the fingers during normal use. Alternatively, it may arise after changes in the internal forces on the anatomy of the digits owing to alterations in the supporting structures of the joints or their control mechanisms, or both. Intrinsic muscle tightness, which is commonly seen in RA hands, may be the result of adaptive shortening or a direct consequence of RA. Previous studies carried out by our group have shown that joints, tendons, and associated synovium in RA hands are consistently hypoxic. Therefore, we formed the hypothesis that there is a difference in hand/forearm muscle oxygen tension in RA versus non-RA. METHODS We measured tissue oxygen levels in the intrinsic muscles of the hands and forearm muscles of 29 patients with a diagnosis of RA, who were undergoing elective surgery. We measured oxygen levels using a microelectrode technique. A total of 31 patients without RA undergoing elective surgery served as matched controls. RESULTS Our results show that the intrinsic muscles of RA patients are significantly more hypoxic than in non-RA controls. Moreover, there is a trend in the RA group for increasing hypoxia in a radial-to-ulnar direction when comparing the different intrinsic muscle groups. We also demonstrate that forearm and thenar and hypothenar muscles are significantly more hypoxic in RA versus non-RA patients. CONCLUSIONS The intrinsic muscle weakness, intrinsic tightness, and muscle wasting observed in RA may not be due to disuse atrophy resulting from joint disease. From our data, we speculate that these changes may be the result of direct muscular involvement in RA leading to muscle hypoxia.
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Abstract
Novel molecular imaging techniques are at the forefront of both preclinical and clinical imaging strategies. They have significant potential to offer visualisation and quantification of molecular and cellular changes in health and disease. This will help to shed light on pathobiology and underlying disease processes and provide further information about the mechanisms of action of novel therapeutic strategies. This review explores currently available molecular imaging techniques that are available for preclinical studies with a focus on optical imaging techniques and discusses how current and future advances will enable translation into the clinic for patients with arthritis.
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Affiliation(s)
- Luke L Gompels
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College, Charing Cross Hospital Campus, 65 Aspenlea Road, London W68LH, UK.
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Gompels LL, Madden L, Lim NH, Inglis JJ, McConnell E, Vincent TL, Haskard DO, Paleolog EM. In vivo fluorescence imaging of E-selectin: quantitative detection of endothelial activation in a mouse model of arthritis. ACTA ACUST UNITED AC 2011; 63:107-17. [PMID: 20954188 DOI: 10.1002/art.30082] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVE In vivo optical imaging can delineate at the macroscopic level processes that are occurring at the cellular and molecular levels. E-selectin, a leukocyte adhesion molecule expressed on endothelium, is induced by tumor necrosis factor α (TNFα) and other cytokines involved in the pathogenesis of rheumatoid arthritis (RA). Collagen-induced arthritis (CIA) in mice is widely used to study the disease mechanisms and identify new treatments for RA. The purpose of this study was to demonstrate E-selectin-targeted fluorescence imaging in vivo in a mouse model of paw edema generated by local injection of TNFα as well as in mice with CIA. METHODS Animals with either CIA or TNFα-induced paw edema were injected with anti-E-selectin or control antibodies labeled with a DyLight 750-nm near-infrared (NIR) probe. In vivo imaging studies were undertaken using an NIR optical imaging system, and images were coregistered with plain radiographic images. RESULTS The mean fluorescence intensity measured over the time-course of TNFα-induced edema demonstrated a 1.97-fold increase (P<0.001) in signal in inflamed paws at 8 hours following injection of anti-E-selectin antibody, as compared to that in the isotype control. In the CIA model, a 2.34-fold increase in E-selectin-targeted signal was demonstrated (P<0.01). Furthermore, significant E-selectin-targeted signal was observed in the paws of animals immunized with collagen that did not display overt signs of arthritis. CONCLUSION E-selectin-targeted fluorescence in vivo imaging is a quantifiable method of detecting endothelial activation in arthritis and can potentially be applied to the quantification of disease and the investigation of the effects of new therapies. Importantly, this approach may also be useful for the detection of subclinical disease in RA.
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Affiliation(s)
- Luke L Gompels
- Kennedy Institute of Rheumatology, Imperial College London, London, UK.
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Sperone A, Dryden NH, Birdsey GM, Madden L, Johns M, Evans PC, Mason JC, Haskard DO, Boyle JJ, Paleolog EM, Randi AM. The transcription factor Erg inhibits vascular inflammation by repressing NF-kappaB activation and proinflammatory gene expression in endothelial cells. Arterioscler Thromb Vasc Biol 2010; 31:142-50. [PMID: 20966395 DOI: 10.1161/atvbaha.110.216473] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE To test whether ETS-related gene (Erg) inhibits tumor necrosis factor (TNF)-α-dependent endothelial activation and inflammation. METHODS AND RESULTS Endothelial activation underlies many vascular diseases, including atherosclerosis. Endothelial activation by proinflammatory cytokines decreases expression of the ETS transcription factor Erg. By using human umbilical vein endothelial cells (HUVECs), we showed that Erg overexpression by adenovirus (AdErg) repressed basal and TNF-α-induced expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule (VCAM), and interleukin 8 (IL-8). Erg inhibited TNF-α-dependent activation of the ICAM-1 promoter, nuclear factor (NF)-κB activity, and NF-κB p65 phosphorylation. Basal NF-κB activity was also inhibited by Erg overexpression. Chromatin immunoprecipitation showed that Erg binds to the ICAM-1 proximal promoter region, which contains 7 putative ETS binding sites. To test the anti-inflammatory role of Erg in vivo, we used a murine model of TNF-α-dependent acute inflammation. The injection of AdErg into the paw decreased TNF-α-induced inflammation compared with control. Finally, staining of human coronary plaques showed loss of Erg expression from the endothelium overlaying active plaque shoulders. CONCLUSIONS We have identified a novel physiological anti-inflammatory pathway under the control of the transcription factor Erg; this pathway inhibits NF-κB-dependent transcription and TNF-α-induced inflammation in vivo. These results suggest a novel approach to anti-inflammatory therapies.
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Affiliation(s)
- Andrea Sperone
- Imperial College London, Hammersmith Hospital, London W12 0NN, England
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Malik NM, Jin P, Raatz Y, Sumariwalla PF, Kiriakidis S, Shepard M, Feldmann M, Paleolog EM. Regulation of the angiopoietin-Tie ligand-receptor system with a novel splice variant of Tie1 reduces the severity of murine arthritis. Rheumatology (Oxford) 2010; 49:1828-39. [PMID: 20547659 DOI: 10.1093/rheumatology/keq163] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
OBJECTIVES To determine the function of the angiopoietin (Ang)-Tie ligand-receptor system, and to assess the effect of Tie1-751, a naturally occurring extracellular domain of the Tie1 receptor derived by alternative splicing, in an in vivo model of RA. METHODS In the murine CIA model, expression of endogenous Ang1, Ang2, Tie1 and Tie2 in whole paws was analysed by quantitative RT-PCR. To assess the effect of inhibition of the Ang-Tie axis, Tie1-751 was expressed and fused to the Fc fragment of human IgG1. The effect of Tie1-751-Fc on human umbilical vein endothelial cell (HUVEC) cytoprotection and migration in response to Ang1, either alone or in combination with VEGF, was investigated. Furthermore, an in vitro angiogenesis assay was used to determine the effect of Tie1-751-Fc on Ang1-mediated angiogenesis. Finally, Tie1-751-Fc was administered in CIA, and the effects on clinical disease and joint architecture of hind foot specimens were determined. RESULTS Gene expression levels of Ang1, Ang2, and receptors Tie1 and Tie2 in whole paws were significantly increased during the progression of arthritis. Tie1-751-Fc significantly inhibited HUVEC cytoprotection and migration in response to Ang1 alone, or Ang1 in combination with VEGF. Tie1-751-Fc also significantly inhibited angiogenesis induced by a combination of Ang1 plus VEGF. Finally, Tie1-751-Fc, when administered intra-peritoneally to arthritic mice, reduced clinical signs of arthritis, damage to joint architecture and infiltration of blood vessels into the synovium. CONCLUSIONS Our data demonstrate that the Ang-Tie ligand-receptor system is dysregulated in CIA. Tie1-751, a novel splice variant of the Tie1 receptor, inhibits Ang1/VEGF signalling, suggesting that Ang inhibition may be of therapeutic benefit in inflammatory arthritis.
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Affiliation(s)
- Nasser M Malik
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College London, Arthritis Research Campaign Building, London, UK
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Abstract
In vivo molecular optical imaging has significant potential to delineate and measure, at the macroscopic level, in vivo biological processes that are occurring at the cellular and molecular level. Optical imaging has already been developed for in vitro and ex vivo applications in molecular and cellular biology (e.g. fluorescence confocal microscopy), but is still at an early stage of development as a whole-animal in vivo imaging technique. Both sensitivity and spatial resolution remain incompletely defined. Rapid advances in hardware technology and highly innovative reporter probes and dyes will be expected to deliver significant insight into perturbations of molecular pathways that occur in disease, ultimately with the potential of translating into future molecular imaging techniques for patients with arthritis. This review will focus on currently available technologies for live in vivo animal optical imaging, including fluorescence reflectance imaging, potential novel tomographic techniques, bioluminescence reporter technology and potential novel labelling techniques, highlighting in particular the potential application of in vivo fluorescence imaging in arthritis.
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Affiliation(s)
- Luke L Gompels
- Kennedy Institute of Rheumatology, Imperial College London, Faculty of Medicine, 65 Aspenlea Road, London W6 8LH, UK.
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Triantaphyllopoulos K, Madden L, Rioja I, Essex D, Buckton J, Malhotra R, Ray K, Binks M, Paleolog EM. In vitro target validation and in vivo efficacy of p38 MAP kinase inhibition in established chronic collagen-induced arthritis model: a pre-clinical study. Clin Exp Rheumatol 2010; 28:176-185. [PMID: 20406612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Accepted: 11/12/2009] [Indexed: 05/29/2023]
Abstract
OBJECTIVES The aim of the present study was to determine the in vivo efficacy of p38 mitogen-activated protein kinase (MAPK) inhibitors, namely GW856553X and GSK678361, in murine models of arthritis. METHODS The effect of p38 MAPK inhibitors was tested in 2 variants of the collagen-induced arthritis model (CIA) in DBA/1 mice, acute arthritis induced by heterologous collagen and chronic relapsing arthritis induced by homologous collagen. Animals were treated after onset of arthritis. Furthermore, post-onset disease efficacy of GSK678361 was tested in the chronic model, so as to determine the effects on established arthritis. In vitro studies were carried out with GW856553X, using human umbilical vein endothelial cells, to determine potential effects of GW856553X on the vasculature. RESULTS In both acute and chronic arthritis, GW856553X reduced signs and symptoms of disease, and protected joints from damage. The effect of GW856553X in chronic CIA was confirmed using an alternative compound, GSK678361. Importantly, treatment with GSK678361 from 14 days post-onset of chronic arthritis completely reversed signs of established disease and joint destruction. Mechanism of action studies demonstrated that GW856553X inhibited endothelial cell migration and angiogenesis in vitro, with reduced pro-inflammatory cytokine production. CONCLUSIONS Suppression of murine CIA by the p38 MAPK inhibitors GW856553X and GSK678361 suggests that they may have therapeutic potential for future use in RA if safe clinical dosing achieves adequate compound exposure.
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Affiliation(s)
- K Triantaphyllopoulos
- Kennedy Institute of Rheumatology and Faculty of Medicine, National Heart and Lung Institute, Imperial College London, UK.
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17
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Abstract
The expansion of the synovial lining of joints in rheumatoid arthritis (RA) necessitates an increase in the vascular supply to the synovium, to cope with the increased requirement for oxygen and nutrients. New blood vessel formation -'angiogenesis'- is recognized as a key event in the formation and maintenance of the pannus in RA, suggesting that targeting blood vessels in RA may be an effective future therapeutic strategy. Although many pro-angiogenic factors have been demonstrated to be expressed in RA synovium, vascular endothelial growth factor (VEGF) has been demonstrated to a have a central involvement in the angiogenic process in RA. Nevertheless, it is unclear whether angiogenesis - whether driven by VEGF and/or other factors - should be considered as a 'cause' or 'consequence' of disease. This ongoing 'chicken vs. egg' debate is difficult, as even the success of angiogenesis inhibition in models of RA does not provide a direct answer to the question. This review will focus on the role of the vasculature in RA, and the contribution of different angiogenic factors in promoting disease. Although no data regarding the effectiveness of anti-angiogenic therapy in RA have been reported to date, the blockade of angiogenesis nevertheless looks to be a promising therapeutic avenue.
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Affiliation(s)
- Ewa M Paleolog
- Kennedy Institute of Rheumatology and Division of Surgery, Oncology, Reproductive Biology and Anaesthetics, Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College, London, UK.
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18
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Abstract
An adequate supply of oxygen and nutrients is essential for survival and metabolism of cells, and consequentially for normal homeostasis. Alterations in tissue oxygen tension have been postulated to contribute to a number of pathologies, including rheumatoid arthritis (RA), in which the characteristic synovial expansion is thought to outstrip the oxygen supply, leading to areas of synovial hypoxia and hypoperfusion. Indeed, the idea of a therapeutic modality aimed at 'starving' tissue of blood vessels was born from the concept that blood vessel formation (angiogenesis) is central to efficient delivery of oxygen to cells and tissues, and has underpinned the development of anti-angiogenic therapies for a range of cancers. An important and well characterized 'master regulator' of the adaptive response to alterations in oxygen tension is hypoxia-inducible factor (HIF), which is exquisitely sensitive to changes in oxygen tension. Activation of the HIF transcription factor signalling cascade leads to extensive changes in gene expression, which allow cells, tissues and organisms to adapt to reduced oxygenation. One of the best characterized hypoxia-responsive genes is the angiogenic stimulus vascular endothelial growth factor, expression of which is dramatically upregulated by hypoxia in many cells types, including RA synovial membrane cells. This leads to an apparent paradox, with the abundant synovial vasculature (which might be expected to restore oxygen levels to normal) occurring nonetheless together with regions of synovial hypoxia. It has been shown in a number of studies that vascular endothelial growth factor blockade is effective in animal models of arthritis; these findings suggest that hypoxia may activate the angiogenic cascade, thereby contributing to RA development. Recent data also suggest that, as well as activating angiogenesis, hypoxia may regulate many other features that are important in RA, such as cell trafficking and matrix degradation. An understanding of the biology of the HIF transcription family may eventually lead to the development of therapies that are aimed at interfering with this key signalling pathway, and hence to modulation of hypoxia-dependent pathologies such as RA.
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Affiliation(s)
- Barbara Muz
- Kennedy Institute of Rheumatology, Charing Cross Campus, Faculty of Medicine, Imperial College, Aspenlea Road, London W6 8LH, UK
| | - Moddasar N Khan
- Kennedy Institute of Rheumatology, Charing Cross Campus, Faculty of Medicine, Imperial College, Aspenlea Road, London W6 8LH, UK
- Renal Section, Division of Medicine, Hammersmith Campus, Faculty of Medicine, Imperial College, Du Cane Road, London W12 0NN, UK
| | - Serafim Kiriakidis
- Kennedy Institute of Rheumatology, Charing Cross Campus, Faculty of Medicine, Imperial College, Aspenlea Road, London W6 8LH, UK
| | - Ewa M Paleolog
- Kennedy Institute of Rheumatology, Charing Cross Campus, Faculty of Medicine, Imperial College, Aspenlea Road, London W6 8LH, UK
- Division of Surgery, Oncology, Reproductive Biology & Anaesthetics, Faculty of Medicine, Imperial College, Aspenlea Road, London W6 8LH, UK
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Sumariwalla PF, Jin P, Zhang J, Ni I, Crawford D, Shepard HM, Paleolog EM, Feldmann M. Antagonism of the human epidermal growth factor receptor family controls disease severity in murine collagen-induced arthritis. ACTA ACUST UNITED AC 2008; 58:3071-80. [PMID: 18821697 DOI: 10.1002/art.23885] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVE To evaluate the therapeutic potential of the human epidermal growth factor receptor (HER) family inhibitor, herstatin, in an animal model of arthritis. METHODS Constructs of herstatin and modified tissue plasminogen activator (tPA)-herstatin were expressed in HEK 293T cells, and secreted protein was analyzed by Western blotting. Tissue PA-herstatin adenovirus (Ad-tPA-Her) was prepared, and titers established. Gene expression of Ad-tPA-Her was determined by polymerase chain reaction using HeLa cells. Pharmacokinetics of gene and protein expression in vivo in liver tissue and serum samples were confirmed via intravenous administration of Ad-tPA-Her. Clinical signs of disease were monitored in arthritic DBA/1 mice after therapeutic administration of Ad-tPA-Her, and histologic analysis of hind foot specimens was performed. RESULTS Native herstatin was not secreted in supernatants, while modified tPA-herstatin was detected in abundance. HeLa cells stably expressed the tPA-herstatin gene when infected with virus. Additionally, tPA-herstatin gene and protein expression was observed over time in mice treated with virus. Importantly, Ad-tPA-Her, when administered therapeutically to arthritic mice, controlled clinical and histologic signs of disease and reduced the number of joints with severe damage. CONCLUSION Our results support the notion that the human epidermal growth factor receptor family has a role in the progression of collagen-induced arthritis. The novel tPA-herstatin fusion protein could be used as an effective therapeutic tool for control of inflammatory disorders involving an angiogenic component.
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Affiliation(s)
- Percy F Sumariwalla
- Kennedy Institute of Rheumatology Division, Faculty of Medicine, Imperial College London, London, UK.
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20
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Akhavani MA, Sivakumar B, Paleolog EM, Kang N. Angiogenesis and plastic surgery. J Plast Reconstr Aesthet Surg 2008; 61:1425-37. [PMID: 18835232 DOI: 10.1016/j.bjps.2008.05.041] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 03/27/2008] [Accepted: 05/29/2008] [Indexed: 01/23/2023]
Abstract
SUMMARY Angiogenesis, the formation of new blood vessels from an existing vascular bed, is a normal physiological process which also underpins many--apparently unrelated--pathological states. It is an integral factor in determining the success or failure of many procedures in plastic and reconstructive surgery. As a result, the ability to control the process would be of great therapeutic benefit. To appreciate the potential benefits and limitations of recent advances in our understanding of angiogenesis, it is important to comprehend the basic physiology of blood vessel formation. This review aims to summarise current knowledge of the way in which angiogenesis is controlled and to look at how disordered vessel development results in pathology relevant to plastic surgery. Through this we hope to provide a comprehensive overview of the recent advances in angiogenesis as they relate to plastic surgery, particularly the promotion of flap survival, tendon healing, nerve regeneration, fracture healing and ulcer treatments.
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21
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Harry LE, Sandison A, Paleolog EM, Hansen U, Pearse MF, Nanchahal J. Comparison of the healing of open tibial fractures covered with either muscle or fasciocutaneous tissue in a murine model. J Orthop Res 2008; 26:1238-44. [PMID: 18404722 DOI: 10.1002/jor.20649] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The objective of this study was to compare the effects of soft tissue coverage by either muscle or fasciocutaneous tissue on the healing of open tibial fractures in a murine model. An open tibial fracture, stripped of periosteum with intramedullary fixation, was created in mice. Experimental groups were devised to allow exclusive comparison of either muscle alone or skin plus fascia in direct contact with healing bone. To exclusively assess the relative efficacy of muscle and fasciocutaneous tissue to promote healing of a fracture stripped of periosteum, a piece of sterile inert material (polytetrafluoroethylene) was positioned anteriorly, excluding skin and fascia (muscle group) or posteriorly, excluding muscle (fasciocutaneous group). Skeletal repair was assessed histologically and quantified by histomorphometry; quantitative peripheral computed tomography (pQCT) and mechanical testing using a four-point bending technique. This standardized, reproducible model allowed characterization of the morphology of open fracture healing. At 28 days postfracture, there was faster healing in the experimental muscle coverage group compared to skin and fascia alone. Furthermore, there was almost 50% more cortical bone content and a threefold stronger union beneath muscle compared to fasciocutaneous tissue (p < 0.05 by one-way ANOVA). Exclusive comparison of muscle and fasciocutaneous tissue in our novel murine model demonstrates that muscle is superior for the coverage of open tibial fractures for both the rate and quality of fracture healing.
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Affiliation(s)
- Lorraine E Harry
- Kennedy Institute of Rheumatology Division, Faculty of Medicine, Imperial College, London, United Kingdom.
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22
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Jin P, Zhang J, Sumariwalla PF, Ni I, Jorgensen B, Crawford D, Phillips S, Feldmann M, Shepard HM, Paleolog EM. Novel splice variants derived from the receptor tyrosine kinase superfamily are potential therapeutics for rheumatoid arthritis. Arthritis Res Ther 2008; 10:R73. [PMID: 18593464 PMCID: PMC2575619 DOI: 10.1186/ar2447] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 06/25/2008] [Accepted: 07/01/2008] [Indexed: 12/21/2022] Open
Abstract
INTRODUCTION Despite the advent of biological therapies for the treatment of rheumatoid arthritis, there is a compelling need to develop alternative therapeutic targets for nonresponders to existing treatments. Soluble receptors occur naturally in vivo, such as the splice variant of the cell surface receptor for vascular endothelial growth factor (VEGF)--a key regulator of angiogenesis in rheumatoid arthritis. Bioinformatics analyses predict that the majority of human genes undergo alternative splicing, generating proteins--many of which may have regulatory functions. The objective of the present study was to identify alternative splice variants (ASV) from cell surface receptor genes, and to determine whether the novel proteins encoded exert therapeutic activity in an in vivo model of arthritis. METHODS To identify novel splice variants, we performed RT-PCR using an mRNA pool representing major human tissue types and tumors. Novel ASV were identified by alignment of each cloned sequence to its respective genomic sequence in comparison with full-length transcripts. To test whether these ASV have biologic activity, we characterized a subset of them for ligand binding, and for efficacy in an animal model of arthritis. The in vivo study was accomplished using adenoviruses expressing secreted ASV. RESULTS We cloned 60 novel human ASV from 21 genes, encoding cell surface receptors--many of which are known to be important in the regulation of angiogenesis. The ASV were characterized by exon extension, intron retention and alternative exon utilization. Efficient expression and secretion of selected ASV--corresponding to VEGF receptor type 1, VEGF receptor type 2, VEGF receptor type 3, angiopoietin receptor Tie1, Met (receptor for hepatocyte growth factor), colony-stimulating factor 1 receptor, platelet-derived growth factor receptor beta, fibroblast growth factor receptor 1, Kit, and RAGE--was demonstrated, together with binding to their cognate ligands. Importantly, ASV derived from VEGF receptor type 1 and Tie1, and to a lesser extent from VEGF receptor type 2 and fibroblast growth factor receptor 1, reduced clinical signs of arthritis in vivo. The reduction was paralleled by decreased joint inflammation and destruction. CONCLUSION The present study shows that unique ASV derived from receptors that play key roles in angiogenesis--namely, VEGF receptor type 1 and, for the first time, Tie1--can markedly reduce arthritis severity. More broadly, our results demonstrate that ASV are a source of novel proteins with therapeutic potential in diseases in which angiogenesis and cellular hyperplasia play a central role, such as rheumatoid arthritis.
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MESH Headings
- Angiopoietin-1/metabolism
- Animals
- Arthritis, Rheumatoid/drug therapy
- Arthritis, Rheumatoid/metabolism
- Cells, Cultured
- Disease Models, Animal
- Endothelium, Vascular/cytology
- Endothelium, Vascular/metabolism
- Humans
- Mice
- Mice, Inbred DBA
- Neovascularization, Physiologic/physiology
- Protein Binding/physiology
- Protein Isoforms/metabolism
- Protein Isoforms/therapeutic use
- RNA, Messenger/metabolism
- Receptor Protein-Tyrosine Kinases/metabolism
- Receptor Protein-Tyrosine Kinases/therapeutic use
- Receptor, TIE-1/metabolism
- Receptor, TIE-1/therapeutic use
- Severity of Illness Index
- Umbilical Veins/cytology
- Umbilical Veins/metabolism
- Vascular Endothelial Growth Factor Receptor-1/metabolism
- Vascular Endothelial Growth Factor Receptor-1/therapeutic use
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Affiliation(s)
- Pei Jin
- Receptor BioLogix, Inc., Palo Alto, CA 94303, USA
| | - Juan Zhang
- Receptor BioLogix, Inc., Palo Alto, CA 94303, USA
| | - Percy F Sumariwalla
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College London, London W6 8LH, UK
| | - Irene Ni
- Receptor BioLogix, Inc., Palo Alto, CA 94303, USA
| | | | - Damian Crawford
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College London, London W6 8LH, UK
| | | | - Marc Feldmann
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College London, London W6 8LH, UK
| | | | - Ewa M Paleolog
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College London, London W6 8LH, UK
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23
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Bainbridge J, Madden L, Essex D, Binks M, Malhotra R, Paleolog EM. Methionine aminopeptidase-2 blockade reduces chronic collagen-induced arthritis: potential role for angiogenesis inhibition. Arthritis Res Ther 2008; 9:R127. [PMID: 18072970 PMCID: PMC2246249 DOI: 10.1186/ar2340] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Revised: 10/24/2007] [Accepted: 12/11/2007] [Indexed: 12/19/2022] Open
Abstract
The enzyme methionine aminopeptidase-2 (MetAP-2) is thought to play an important function in human endothelial cell proliferation, and as such provides a valuable target in both inflammation and cancer. Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with increased synovial vascularity, and hence is a potential therapeutic target for angiogenesis inhibitors. We examined the use of PPI-2458, a selective non-reversible inhibitor of MetAP-2, in disease models of RA, namely acute and chronic collagen-induced arthritis (CIA) in mice. Whilst acute CIA is a monophasic disease, CIA induced with murine collagen type II manifests as a chronic relapsing arthritis and mimics more closely the disease course of RA. Our study showed PPI-2458 was able to reduce clinical signs of arthritis in both acute and chronic CIA models. This reduction in arthritis was paralleled by decreased joint inflammation and destruction. Detailed mechanism of action studies demonstrated that PPI-2458 inhibited human endothelial cell proliferation and angiogenesis in vitro, without affecting production of inflammatory cytokines. Furthermore, we also investigated release of inflammatory cytokines and chemokines from human RA synovial cell cultures, and observed no effect of PPI-2458 on spontaneous expression of cytokines and chemokines, or indeed on the angiogenic molecule vascular endothelial growth factor (VEGF). These results highlight MetAP-2 as a good candidate for therapeutic intervention in RA.
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Affiliation(s)
- John Bainbridge
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College London, 1, Aspenlea Road, London W6 8LH, UK.
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24
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Sivakumar B, Akhavani MA, Winlove CP, Taylor PC, Paleolog EM, Kang N. Synovial hypoxia as a cause of tendon rupture in rheumatoid arthritis. J Hand Surg Am 2008; 33:49-58. [PMID: 18261665 DOI: 10.1016/j.jhsa.2007.09.002] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 09/05/2007] [Accepted: 09/05/2007] [Indexed: 02/02/2023]
Abstract
PURPOSE Hypoxia and angiogenesis are now recognized as being important events in the perpetuation of joint destruction in rheumatoid arthritis (RA). In 50% of patients with RA, however, the disease also involves inflammation of the synovial tissue surrounding the tendons, which is associated with multiple ruptures and poor prognosis for long-term hand function. The aim of this study was to determine whether hypoxia and angiogenesis may also play a role in RA tendon disease. METHODS Matched in vivo synovial oxygen measurements (invasive and encapsulating tenosynovium and joint synovium) were taken intraoperatively using a microelectrode technique in patients having elective hand surgery for RA. Patients having elective hand surgery for indications other than inflammatory synovitis were recruited as controls. In parallel, RA synovial tissue was harvested and stained for vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-2alpha. Tissue was also cultured under either hypoxic (1% O(2)) or normoxic (21% O(2)) conditions to investigate the effect of hypoxia on the expression of VEGF and its soluble receptor, as well as on the key cytokines interleukin (IL)-6, IL-8, IL-10 and the chemokine monocyte chemoattractant protein-1. RESULTS Invasive tenosynovium was observed to be significantly more hypoxic than either noninvasive tenosynovium or joint synovium in the same patients. Furthermore, RA tenosynovium was shown to be more hypoxic than tenosynovium in patients without RA. This hypoxia was accompanied by expression of VEGF and hypoxia-inducible factor-2alpha. Using in vitro joint synovial cell cultures, upregulation of VEGF expression was shown to be a consequence of this in vivo hypoxia. Furthermore, hypoxia downregulated release of monocyte chemoattractant protein-1 and the immunoregulatory cytokine IL-10. CONCLUSIONS These data demonstrate that hypoxia is a feature of rheumatoid tendon disease and differentially regulates angiogenesis and the inflammatory cascade in RA.
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Affiliation(s)
- Branavan Sivakumar
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College London, London, United Kingdom
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25
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Pertyńska-Marczewska M, Kiriakidis S, Wait R, Beech J, Feldmann M, Paleolog EM. Advanced glycation end products upregulate angiogenic and pro-inflammatory cytokine production in human monocyte/macrophages. Cytokine 2005; 28:35-47. [PMID: 15341924 DOI: 10.1016/j.cyto.2004.06.006] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2003] [Revised: 04/19/2004] [Accepted: 06/19/2004] [Indexed: 10/26/2022]
Abstract
Glucose can react non-enzymatically with amino groups of, for example, proteins, to yield derivatives termed advanced glycation end products (AGE), which contribute to many chronic progressive diseases associated with microvascular complications. The study aimed to determine the effect of AGE-modified albumin on THP-1 cells and human monocyte-derived macrophages. Bovine serum albumin (BSA) or human serum albumin (HSA), modified by glucose-derived AGE, was prepared by incubation with glucose for differing periods of time. Alternatively, BSA was incubated with sodium cyanoborohydride and glyoxylic acid to produce N(epsilon)-(carboxymethyl)lysine-modified BSA (CML-BSA). Stimulation for 24h of THP-1 cells with BSA, incubated for 6-8 weeks with glucose, induced significant VEGF release. Human monocyte-derived macrophages stimulated with extensively glycated HSA also showed significant VEGF release, as well as upregulation of IL-8 production, incubation for 6h with extensively glycated HSA increased release of TNFalpha and expression of tissue factor. Finally, addition of CML-BSA resulted in significant induction of TNFalpha and VEGF release. We demonstrate that a range of different methods of glycation of BSA and HSA, including CML-BSA, resulted in the induction of VEGF, TNFalpha, IL-8 and expression of tissue factor, according to length of stimulation and different glycation products used, suggesting that AGE-induced activation of macrophages may contribute to vascular complications by regulation of angiogenic, inflammatory and pro-coagulant processes.
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Affiliation(s)
- Magdalena Pertyńska-Marczewska
- Kennedy Institute of Rheumatology, Arthritis Research Campaign Building, Faculty of Medicine, Imperial College, 1, Aspenlea Road, Hammersmith, London W6 8LH, UK
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26
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Abstract
The concept of manipulation of the vascular bed to either increase or decrease the number of blood vessels has attracted considerable interest. This review focuses on angiogenesis as a therapeutic target, particularly in the context of cancer and arthritis, as well as on promoting angiogenesis in cardiovascular disease and the healing of bone fractures. Although once touted almost as a panacea for treatment of tumors, as well as other diseases associated with angiogenesis, such as diabetic retinopathy or rheumatoid arthritis, it is now clear that such enthusiasm was somewhat premature. Similarly, some clinical trials of therapeutic angiogenesis for the management of cardiovascular disease have been disappointing. Nevertheless, this exciting field of research holds promise for more targeted therapies.
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Affiliation(s)
- Branavan Sivakumar
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College, London
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27
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Ibrahim S, Paleolog EM. 4th meeting of the EU research network EUROME: from the identification of genes and cellular networks in murine models of arthritis to novel therapeutic intervention strategies in rheumatoid arthritis, London, UK, 9 March 2004. Arthritis Res Ther 2004; 6:155-8. [PMID: 15225359 PMCID: PMC464915 DOI: 10.1186/ar1200] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2004] [Accepted: 05/19/2004] [Indexed: 11/20/2022] Open
Abstract
Rheumatoid arthritis (RA) is a common human disease with a prevalence of about 1% in most parts of the world. At the time of symptom onset it is difficult to predict the severity of subsequent disease course. After 2 years joint erosions are seen in most patients, and most patients become clinically disabled within 20 years. A recent meeting at the Kennedy Institute of Rheumatology (Imperial College, London) brought together representatives from several European centres of excellence, to discuss research funded by the EU Framework 5 Quality of Life Programme. This research network combines gene and protein expression profiling with different animal models of RA to identify cells, genes and pathways contributing to arthritis initiation, progression and chronicity. The studies discussed highlight the reality that collaboration between different research groups is the basis of groundbreaking research and, it is hoped, eventual new therapies for RA.
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Affiliation(s)
- Saleh Ibrahim
- Institute of Immunology, Medical Faculty, University of Rostock, Germany
| | - Ewa M Paleolog
- Kennedy Institute of Rheumatology, Faculty of Medicine, Imperial College, London, UK
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28
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Abstract
Formation of new blood vessels, which is fundamental in embryonic development, occurs through a combination of angiogenesis and vasculogenesis. Angiogenesis also plays a vital role postnatally, especially in reparative processes such as wound and fracture healing. Some of these events, especially in fracture healing, recapitulate processes observed in developmental angiogenesis. However, dysregulated angiogenesis is well documented to underlie a number of pathological disorders, including rheumatoid arthritis (RA). The vascular endothelial growth factor (VEGF)/VEGF receptor system is the best characterized regulator of angiogenesis. VEGF is expressed in a range of cells in response to soluble mediators (such as cytokines and growth factors), cell-bound stimuli (such as CD40 ligand), and environmental factors (such as hypoxia). As a consequence, this molecule is vital in the modulation of physiological and pathological angiogenesis. This review will focus in particular on the role played by VEGF in embryogenesis and skeletal growth, in fracture healing (in which increased angiogenesis is likely to be beneficial in promoting union), and in RA (in which excessive angiogenesis is thought to play a significant role in disease pathogenesis). In the not-too-distant future, targeting VEGF may prove to be of benefit in the treatment of diseases associated with excessive or aberrant angiogenesis, such as malignancies and RA.
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Affiliation(s)
- Lorraine E Harry
- Kennedy Institute of Rheumatology & Division of Surgery, Anaesthetics and Intensive Care, Faculty of Medicine, Imperial College, London, United Kingdom
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29
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Abstract
Rheumatoid arthritis (RA) is a chronic destructive musculo-skeletal disorder, associated with thickening of the synovial membrane lining the joints, inflammation and hyperproliferation of synovial cells, as well as a pro-inflammatory cytokine cascade, leukocyte infiltration, and tissue damage and bone resorption. An early event in RA is an alteration in blood vessel density and prominent neovascularisation. The hyperplasia of the synovium necessitates a compensatory increase in the number of blood vessels to nourish and oxygenate the tissue. However, angiogenesis may not keep pace with synovial proliferation, leading to regions of hypoperfusion and hypoxia. VEGF, a potent endothelial cell mitogen, is expressed in RA synovium and elevated in the serum of RA patients. We have reported that dissociated RA synovial membrane cells spontaneously secrete VEGF, and that release of VEGF by these cells is upregulated by cytokines and hypoxia. In a murine model of RA, VEGF is released from synovial cells isolated from the knees of arthritic but not healthy mice, and the extent of VEGF production correlates with the severity of arthritis. VEGF thus appears to play a key role in mediating alterations in synovial vessel density in arthritis. As a consequence, RA may be a potential target for anti-angiogenic therapy, and targeting VEGF may prove to be especially beneficial.
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30
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Afuwape AO, Feldmann M, Paleolog EM. Adenoviral delivery of soluble VEGF receptor 1 (sFlt-1) abrogates disease activity in murine collagen-induced arthritis. Gene Ther 2003; 10:1950-60. [PMID: 14528319 DOI: 10.1038/sj.gt.3302104] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The angiogenic factor VEGF promotes synovitis and bone erosion in rheumatoid arthritis (RA). Previously, we have demonstrated that VEGF expression correlates with disease severity in RA patients and in murine collagen-induced arthritis (CIA). In this study, we adopted an adenoviral gene delivery system expressing soluble VEGF receptor 1 (sFlt-1) to further study the role of VEGF in CIA. Arthritis was induced in DBA/1 mice by injection of bovine collagen. Adenoviruses expressing human soluble VEGF receptor 1 (AdvsFlt-1), or without transgene (Adv0), were injected intravenously on the first day of arthritis. We found that disease severity and paw swelling were significantly suppressed in mice receiving AdvsFlt-1, when compared to untreated or Adv0-treated mice. Expression of sFlt-1 peaked 24 h after injection, with protein detectable in the liver, synovial issue and serum, but rapidly decreased by 72 h. The effect of sFlt-1 expression on signs of disease was paralleled by reduced joint destruction and decreased expression of the vascular marker von Willebrand factor. In summary, adenoviral delivery of human soluble VEGF receptor type 1 significantly suppressed disease activity in CIA. The actions of AdvsFlt-1 are likely to be mediated by reduced synovial neovascularization, and these results support the concept that VEGF blockade may be an effective therapeutic adjunct for the treatment of RA.
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Affiliation(s)
- A O Afuwape
- Kennedy Institute of Rheumatology Division, Faculty of Medicine, Imperial College of Science, Technology and Medicine, London, UK
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Voskuyl AE, Hazes JMW, Zwinderman AH, Paleolog EM, van der Meer FJM, Daha MR, Breedveld FC. Diagnostic strategy for the assessment of rheumatoid vasculitis. Ann Rheum Dis 2003; 62:407-13. [PMID: 12695150 PMCID: PMC1754537 DOI: 10.1136/ard.62.5.407] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To determine the clinical features associated with histologically proven rheumatoid vasculitis (HRV) and the additional diagnostic value of serological markers in an inception cohort of 81 patients with rheumatoid arthritis (RA) suspected of RV. METHODS The presence and number of recently developed extra-articular manifestations (EAMs) and a weighted EAM score, as well as the levels of serological markers, were compared between 31 patients with RA with histologically proven vasculitis and 50 patients with RA in whom vasculitis could not be documented histologically. The following markers were evaluated: circulating immune complexes, complement components C3 and C4, class-specific rheumatoid factors (IgM RF, IgG RF, IgA RF), antineutrophil cytoplasmic antibodies, antinuclear antibodies, antiendothelial antibodies, circulating intercellular adhesion molecule-1 and -3, circulating vascular cell adhesion molecule and E-selectin, cellular fibronectin, von Willebrand factor antigen, and C reactive protein. The diagnostic value of these markers, in addition to the clinical features, was evaluated with logistic regression analysis. RESULTS Peripheral neuropathy or purpura/petechiae, or both, were the most important clinical features to discriminate patients with RA with and without histologically proven RV. The presence of a high number of EAMs and a higher weighted EAM score in patients with RA suspected of vasculitis were also associated with an increased probability of histologically proven RV. After adjustment for EAMs, only the combination of an increased serum IgA RF level and a decreased serum C3 level appeared to make an additional contribution to the diagnosis histologically proven RV. Evidence of systemic vasculitis was found in a muscle biopsy of the rectus femoris in 9/14 (64%) patients with vasculitis with neuropathy and in 3/11 (27%) patients with purpura/petechiae and vasculitis of the skin. CONCLUSIONS In the diagnostic process of RV the presence of peripheral neuropathy and/or purpura/petechiae or a high weighted EAM score will increase the probability of histologically proven RV. Of the circulating factors previously suggested to be markers for RV only IgA RF and C3 further increase the probability of histologically proven RV and may be useful to guide diagnostic decisions.
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Affiliation(s)
- A E Voskuyl
- Department of Rheumatology, Leiden University Medical Centre, Leiden, The Netherlands.
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Afuwape AO, Kiriakidis S, Paleolog EM. The role of the angiogenic molecule VEGF in the pathogenesis of rheumatoid arthritis. Histol Histopathol 2003; 17:961-72. [PMID: 12168808 DOI: 10.14670/hh-17.961] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The expansion of the synovial lining of joints in rheumatoid arthritis (RA), and the subsequent invasion by the pannus of underlying cartilage and bone, necessitates an increase in the vascular supply to the synovium, to cope with the increased requirement for oxygen and nutrients. New blood vessel formation - 'angiogenesis' - is now recognised as a key event in the formation and maintenance of the pannus in RA. Although many pro-angiogenic factors have been demonstrated to be expressed in RA synovium, the potent pro-angiogenic cytokine vascular endothelial growth factor (VEGF) has been demonstrated to have a central involvement in the angiogenic process in RA. The additional activity of VEGF as a vascular permeability factor may also increase oedema and hence joint swelling in RA. Several studies, including those from the Kennedy Institute of Rheumatology Division, have shown that targeting angiogenesis in animal models of arthritis ameliorates disease. Inhibition of angiogenesis, as an adjunct to existing therapy of RA, or even as a stand-alone treatment, would not only prevent delivery of nutrients to the synovium, but could also lead to vessel regression and possibly reversal of disease.
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Affiliation(s)
- A O Afuwape
- Kennedy Institute of Rheumatology Division, Faculty of Medicine, Imperial College of Science Technology and Medicine, London, UK
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Sumariwalla PF, Cao Y, Wu HL, Feldmann M, Paleolog EM. The angiogenesis inhibitor protease-activated kringles 1-5 reduces the severity of murine collagen-induced arthritis. Arthritis Res Ther 2003; 5:R32-9. [PMID: 12716451 PMCID: PMC154428 DOI: 10.1186/ar608] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2002] [Revised: 09/27/2002] [Accepted: 10/02/2002] [Indexed: 11/10/2022] Open
Abstract
During rheumatoid arthritis there is enlargement and increased cellularity of the synovial lining of joints, before invasion by the synovium of the underlying cartilage and bone. This increased tissue mass requires a network of blood vessels to supply nutrients and oxygen. Disruption of synovial angiogenesis is thus a desirable aim of antiarthritic therapies. Protease-activated kringles 1-5 (K1-5) is an angiogenesis inhibitor related to angiostatin. In common with angiostatin, K1-5 contains the first four kringle domains of plasminogen, but also encompasses the kringle 5 domain, which confers enhanced antiangiogenic activity when compared with angiostatin. The purpose of the present study was to assess the effect on murine arthritis of K1-5. Arthritis was induced in DBA/1 mice by a single injection of bovine collagen. Treatment with K1-5 was commenced on the day of arthritis onset and continued for 10 days, until the end of the experiment. Daily intraperitoneal administration of K1-5 (2 mg/kg body weight) significantly reduced both paw swelling and clinical score (a composite index of the number of arthritic limbs and the severity of disease). The clinical efficacy of this treatment was reflected by a reduction in joint inflammation and destruction, as assessed histologically. These data suggest that antiangiogenic therapies, which block formation of new blood vessels and hence reduce synovial expansion, might be effective in treating rheumatoid arthritis.
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Affiliation(s)
- Percy F Sumariwalla
- Kennedy Institute of Rheumatology Division, Faculty of Medicine, Imperial College of Science, Technology and Medicine, London, UK.
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Abstract
The expansion of the synovial lining of joints in rheumatoid arthritis (RA) and the subsequent invasion by the pannus of underlying cartilage and bone necessitate an increase in the vascular supply to the synovium, to cope with the increased requirement for oxygen and nutrients. The formation of new blood vessels - termed 'angiogenesis' - is now recognised as a key event in the formation and maintenance of the pannus in RA. This pannus is highly vascularised, suggesting that targeting blood vessels in RA may be an effective future therapeutic strategy. Disruption of the formation of new blood vessels would not only prevent delivery of nutrients to the inflammatory site, but could also lead to vessel regression and possibly reversal of disease. Although many proangiogenic factors are expressed in the synovium in RA, the potent proangiogenic cytokine vascular endothelial growth factor (VEGF) has been shown to a have a central involvement in the angiogenic process in RA. The additional activity of VEGF as a vascular permeability factor may also increase oedema and hence joint swelling in RA. Several studies have shown that targeting angiogenesis in animal models of arthritis ameliorates disease. Our own study showed that inhibition of VEGF activity in murine collagen-induced arthritis, using a soluble VEGF receptor, reduced disease severity, paw swelling, and joint destruction. Although no clinical trials of anti-angiogenic therapy in RA have been reported to date, the blockade of angiogenesis - and especially of VEGF - appears to be a promising avenue for the future treatment of RA.
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Affiliation(s)
- Ewa M Paleolog
- Kennedy Institute of Rheumatology Division, Faculty of Medicine, Imperial College of Science, Technology and Medicine, London, UK.
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Ballara S, Taylor PC, Reusch P, Marmé D, Feldmann M, Maini RN, Paleolog EM. Raised serum vascular endothelial growth factor levels are associated with destructive change in inflammatory arthritis. Arthritis Rheum 2001; 44:2055-64. [PMID: 11592367 DOI: 10.1002/1529-0131(200109)44:9<2055::aid-art355>3.0.co;2-2] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To determine whether elevated levels of the angiogenic cytokine vascular endothelial growth factor (VEGF), detected on presentation to an early arthritis clinic, are associated with the development of chronic and erosive arthritis. METHODS Concentrations of VEGF and its soluble receptor, soluble fms-like tyrosine kinase 1 (sFlt-1), were measured by enzyme-linked immunosorbent assay in serum samples from patients with early (<2 years from onset) arthritic symptoms in the peripheral joints, namely early rheumatoid arthritis (RA), self-limiting arthritis (viral, reactive, and idiopathic inflammatory arthritis), or psoriatic arthritis. In addition, measurements were made in random samples from patients with longstanding (>3 years from symptom onset) RA treated with disease-modifying antirheumatic drugs, from patients with osteoarthritis (OA), and from patients with polyarthralgia without arthritis, as well as from nonarthritic controls. RESULTS Serum VEGF levels at presentation were elevated in patients with inflammatory arthritis (RA, psoriatic, and self-limiting arthritis) as well as in patients with OA, in comparison with nonarthritic controls. Moreover, serum VEGF concentrations were significantly higher in patients with early RA than in patients with self-limiting arthritis. Serum VEGF levels at presentation in patients with early RA correlated significantly with the development of radiographic damage after 1 year. Improvement in the clinical symptoms of RA was associated with a reduction in serum VEGF levels. Serum sFlt-1 levels were raised in patients with early and longstanding RA and in those with self-limiting arthritis, and correlated positively with the serum VEGF concentrations in patients with inflammatory arthritis. CONCLUSION These findings implicate the proangiogenic cytokine VEGF in the persistence of inflammatory arthritis, and support the hypothesis that expansion of the synovial vasculature is important for the development of joint destruction in RA.
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Affiliation(s)
- S Ballara
- Imperial College School of Medicine, London, UK
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Chaly YV, Paleolog EM, Kolesnikova TS, Tikhonov II, Petratchenko EV, Voitenok NN. Neutrophil alpha-defensin human neutrophil peptide modulates cytokine production in human monocytes and adhesion molecule expression in endothelial cells. Eur Cytokine Netw 2000; 11:257-66. [PMID: 10903805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Defensins, a family of small, cationic, antimicrobial peptides, are found in mammals, insects and plants. alpha-defensins are stored in granules of neutrophils and released upon activation by exocytosis. It was shown here that human neutrophil peptide (HNP), at concentrations of 10(-8) -10(-9) M, up-regulated the expression of TNF-alpha and IL-1 beta in monocytes activated with Staphylococcus aureus or PMA, while expression of IL-10 mRNA was down-regulated and production of IL-8 was not affected. HNP alone was unable to induce TNF-alpha or IL-1 beta expression in resting monocytes. At concentrations of 10(-4) -10(-5)M, HNP was cytotoxic for monocytes in serum-free medium. The cytotoxicity was abrogated in the presence of serum, while a cytokine-modulating effect of HNP was observed in the presence of serum and in whole blood, suggesting that this mechanism may function in vivo. Similarly, serum did not abrogate bactericidal activity of HNP. It was also demonstrated herein that HNP at 10 (-8) -10(-9) M, attenuated the inhibitory action of dexamethasone on TNF-alpha production. In parallel to monocyte studies, we have showed that HNP at concentrations ranging from 10(-9)M to 10(-6)M caused about 5-fold suppression of VCAM-1 expression in TNF-alpha-activated human umbilical vein endothelial cells, while the ICAM-1 expression was not affected. Our findings suggest that neutrophil defensins have the potential to modulate the inflammatory responses through regulation of cytokine production and adhesion molecule expression.
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Affiliation(s)
- Y V Chaly
- Laboratory of Cellular and Molecular Immunology, Institute of Hematology and Blood Transfusion, Dolginovski Trakt 160, Minsk, 223059, Belarus.
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Abstract
Musculoskeletal disorders such as rheumatoid arthritis (RA) and osteoarthritis are a common cause of pain and disability. The vasculature is an important component of the musculoskeletal system, and vascularization is a key event in the development of normal cartilage and bone. By promoting the delivery of nutrients, oxygen and cells, blood vessels help maintain the structural and functional integrity of joints and soft tissue and may facilitate tissue repair and healing. The identification of pro-angiogenic mediators such as vascular endothelial growth factor (VEGF) has led to the development of antiangiogenic therapies for the treatment of neoplastic diseases. The important role of angiogenesis, and especially VEGF, in the pathogenesis of joint disorders such as RA suggests that antiangiogenic therapy may be a useful adjunct to existing approaches in RA.
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Affiliation(s)
- S C Ballara
- Kennedy Institute of Rheumatology, London, United Kingdom
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Paleolog EM, Fava RA. Angiogenesis in rheumatoid arthritis: implications for future therapeutic strategies. Springer Semin Immunopathol 1998; 20:73-94. [PMID: 9836370 DOI: 10.1007/bf00832000] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
MESH Headings
- Animals
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/therapeutic use
- Antibody Specificity
- Arthritis, Rheumatoid/etiology
- Arthritis, Rheumatoid/pathology
- Arthritis, Rheumatoid/therapy
- Biological Factors/physiology
- Biopsy
- Bursa, Synovial/cytology
- Bursa, Synovial/immunology
- Chemokines/analysis
- Chemokines/pharmacology
- Fibroblasts/chemistry
- Fibroblasts/drug effects
- Fluorescent Antibody Technique, Indirect
- Growth Substances/physiology
- Humans
- Neovascularization, Pathologic/physiopathology
- Neovascularization, Pathologic/therapy
- Platelet Endothelial Cell Adhesion Molecule-1/immunology
- Receptors, Vitronectin/immunology
- Time Factors
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Paleolog EM, Young S, Stark AC, McCloskey RV, Feldmann M, Maini RN. Modulation of angiogenic vascular endothelial growth factor by tumor necrosis factor alpha and interleukin-1 in rheumatoid arthritis. Arthritis Rheum 1998; 41:1258-65. [PMID: 9663484 DOI: 10.1002/1529-0131(199807)41:7<1258::aid-art17>3.0.co;2-1] [Citation(s) in RCA: 261] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To investigate the regulation of expression of the angiogenic cytokine vascular endothelial growth factor (VEGF) in rheumatoid arthritis (RA), in order to determine whether new blood vessel formation could be a potential therapeutic target in RA. METHODS Dissociated RA synovial membrane cells were cultured in the presence of cytokine inhibitors, or under hypoxic conditions. Serum VEGF levels were serially measured in RA patients enrolled in clinical trials of anti-tumor necrosis factor alpha (anti-TNFalpha) monoclonal antibody treatment. RESULTS Combined neutralization of TNFalpha and interleukin-1 (IL-1) in RA synovial membrane cultures reduced VEGF release by 45% (P < 0.05 versus control), although blockade of either TNFalpha or IL-1 activities alone resulted in only small inhibitory effects. In addition, release of VEGF from RA synovial membrane cells was selectively up-regulated by hypoxia. Serum VEGF levels were significantly elevated in RA patients relative to control subjects, and correlated with disease activity. Treatment of RA patients with anti-TNFalpha significantly decreased serum VEGF, and this effect was enhanced by cotreatment with methotrexate. CONCLUSION Inhibition of TNFalpha and IL-1 activity in vivo could reduce the drive to new blood vessel formation, and hence pannus mass, adding to other therapeutic effects of anti-TNFalpha therapy in RA.
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Taichman NS, Cruchley AT, Fletcher LM, Hagi-Pavli EP, Paleolog EM, Abrams WR, Booth V, Edwards RM, Malamud D. Vascular endothelial growth factor in normal human salivary glands and saliva: a possible role in the maintenance of mucosal homeostasis. J Transl Med 1998; 78:869-75. [PMID: 9690564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Saliva is an enriched milieu containing biologically active proteins, including several different growth factors and cytokines. This study documents that vascular endothelial growth factor (VEGF), a potent, multifunctional, angiogenic cytokine, is a component of normal human saliva. VEGF was measured by ELISA in whole saliva (median concentration, 460 pg/ml) and in ductal secretions obtained from the parotid (277 pg/ml) and the submandibular-sublingual (80 pg/ml) salivary glands. VEGF seems to be synthesized endogenously by the salivary glands because both VEGF mRNA and protein (as revealed by in situ reverse transcriptase-PCR and by immunohistochemistry, respectively) colocalized to serous acinar cells and ductal epithelial cells within the parotid, submandibular, and minor salivary glands. These findings point to the existence of a "salivary VEGF system." It is possible that salivary VEGF plays a role in regulating physiologic and pathologic angiogenic and other vascular responses in salivary and mucosal tissues. And in particular, the presence of VEGF in saliva may contribute to the remarkable healing capacity of the oral mucosa as well as other regions of the digestive tract.
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Affiliation(s)
- N S Taichman
- Department of Pathology, University of Pennsylvania, School of Dental Medicine, Philadelphia 19104-6002, USA
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Abstract
Although initially described as an immunomodulatory cytokine, interleukin-10 (IL-10) has also been proposed to exert proinflammatory effects both in vivo and in vitro. In particular, studies in IL-10 transgenic mice have suggested that IL-10 may activate vascular endothelium to promote leucocyte adhesion and extravasation. In the present study we investigated whether IL-10 activates endothelial cells either directly or indirectly, via signals produced by leucocytes in the endothelial cell environment, using a co-culture of human umbilical vein endothelial cells and peripheral blood mononuclear cells (PBMC). No direct effects of IL-10 on endothelial cell responses were observed. However, in the presence of phytohaemagglutinin-activated PBMC, IL-10 increased the expression on endothelial cells of vascular cell adhesion molecule-1 (VCAM-1) but not of intercellular adhesion molecule-1, E-selectin or major histocompatibility complex (MHC) antigens, an effect mediated by PBMC-derived soluble factors. We also observed that interferon-gamma (IFN-gamma) antagonized VCAM-1 expression on endothelial cells mediated by IL-4 and IL-13. Since IL-10 has previously been documented to down-regulate release of IFN-gamma by PBMC, we propose that the IL-10-mediated reduction of IFN-gamma production by PBMC results in enhanced responsiveness of endothelial cells to PBMC-derived IL-4 and IL-13, and thus increased expression of VCAM-1. Our results suggest that the relative balance of cytokines produced by infiltrating cells in developing inflammatory lesions may differentially modulate endothelial responsiveness in vivo, and that IL-10 might indirectly stabilize VCAM-1 expression on endothelial cells by affecting the balance of leucocyte-derived cytokines in the endothelial environment.
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Affiliation(s)
- C Fiehn
- Kennedy Institute of Rheumatology, London, UK
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Zeman K, Kantorski J, Paleolog EM, Feldmann M, Tchórzewski H. The role of receptors for tumour necrosis factor-alpha in the induction of human polymorphonuclear neutrophil chemiluminescence. Immunol Lett 1996; 53:45-50. [PMID: 8946217 DOI: 10.1016/0165-2478(96)02613-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Tumour necrosis factor-alpha (TNF-alpha) is a potent mediator of inflammation, which exerts profound effects on polymorphonuclear neutrophils (PMN). TNF-alpha binds to distinct cell surface receptors termed p55 and p75, expressed in approximately equal amounts on the PMN surface. We have studied the effects of TNF-alpha on the priming of F-Met-Leu-Phe (FMLP)-stimulated oxidative metabolism of PMN, using a luminol-enhanced chemiluminescence assay, and have examined the relative roles of PMN receptors for TNF-alpha in priming this oxidative metabolism, using antibodies with p55 and p75 receptor-specific agonistic and antagonistic activities. We have obtained the following results: (1) Antibody Htr-9 with agonistic activity at the p55 receptor mimicked the effect of TNF-alpha; however, a combination of Htr-9 and TNF-alpha did not results in any further increase in chemiluminescence relative to the response observed with TNF-alpha alone. The p75 agonistic antibody MR2-1 actually decreased basal and FMLP-enhanced chemiluminescence. Additionally, MR2-1 substantially inhibited the effects of both TNF-alpha itself and of the p55 agonist Htr-9. (2) Addition of antibodies with antagonistic activities at the p55 (antibody TBP-2) and p75 (antibody Utr-1) receptors resulted in a marked inhibition of the PMN response to TNF-alpha. A combination of both Utr-1 and TBP-2 was most effective at inhibiting the action of TNF. We have confirmed previously published observations that TNF-alpha alone effectively stimulates the oxidative metabolism of PMN in vitro, and that pre-incubation of PMN with TNF-alpha enhances subsequent generation of oxidative metabolites in response to FMLP. We conclude that both p55 and p75 receptors play a critical role in mediating the activation of PMN by TNF-alpha.
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Affiliation(s)
- K Zeman
- Department of Clinical Immunology, Military Medical Academy, Lódź, Poland
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Paleolog EM, Hunt M, Elliott MJ, Feldmann M, Maini RN, Woody JN. Deactivation of vascular endothelium by monoclonal anti-tumor necrosis factor alpha antibody in rheumatoid arthritis. Arthritis Rheum 1996; 39:1082-91. [PMID: 8670315 DOI: 10.1002/art.1780390703] [Citation(s) in RCA: 185] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVE To assess whether monoclonal antibody to tumor necrosis factor alpha (TNF alpha) reduces endothelial activation in rheumatoid arthritis (RA). METHODS Levels of serum E-selectin, intercellular adhesion molecule 1 (ICAM-1), and vascular cell adhesion molecule 1 (VCAM-1), and circulating leukocytes (differential counts) were measured in RA patients before and up to 4 weeks after infusion of either placebo or chimeric anti-TNF alpha antibody cA2 (1 or 10 mg/kg). RESULTS Treatment with anti-TNF alpha decreased serum E-selectin and ICAM-1 levels, with the earliest detectable changes observed on days 1-3 after anti-TNF alpha infusion. No effect on VCAM-1 levels was detected. In parallel, there was a rapid and sustained increase in circulating lymphocytes. The extent of the decrease in serum E-selectin and ICAM-1 levels and the increase in lymphocyte counts was significantly higher (P < or = 0.05) in patients in whom a clinical benefit of anti-TNF alpha was observed ( > or = 20% response, by Paulus criteria, at week 4) compared with that in patients who failed to respond to anti-TNF alpha at this time point. CONCLUSION We propose that decreased serum levels of adhesion molecules may reflect diminished activation of endothelial cells in the synovial microvasculature, leading to reduced migration of leukocytes into synovial joints, and thus prolonging the therapeutic effect of anti-TNF alpha in RA.
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Paleolog EM, Delasalle SA, Buurman WA, Feldmann M. Functional activities of receptors for tumor necrosis factor-alpha on human vascular endothelial cells. Blood 1994; 84:2578-90. [PMID: 7919375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Tumor necrosis factor-alpha (TNF-alpha) plays a critical role in the control of endothelial cell function and hence in regulating traffic of circulating cells into tissues in vivo. Stimulation of endothelial cells in vitro by TNF-alpha increases the surface expression of leukocyte adhesion molecules, enhances cytokine production, and induces tissue factor procoagulant activity. In the present study, we have examined the relative roles of the two cell surface receptors for TNF-alpha (p55 and p75) on endothelial cells, using antibodies with both agonistic and antagonistic activities. We report that anti-p55 receptor agonistic antibody Htr-9 induces the expression of tissue factor antigen and the release of interleukin-8 (IL-8) and granulocyte-macrophage colony-stimulating factor (GM-CSF). In contrast, there is very little or no activation of endothelial cell responses by an anti-p75 agonist. TNF-alpha-induced expression of tissue factor and adhesion molecules, and release of IL-8 and GM-CSF, are decreased by antibodies with antagonistic activities for either receptor, although the effect of anti-p55 antibodies is markedly greater than that of anti-p75 antibodies. The responses of endothelial cells to lymphotoxin/TNF-beta are significantly decreased by anti-p55 antagonists alone. Our data suggest that endothelial cell responses to TNF-alpha, such as expression of tissue factor and adhesion molecules for mononuclear cells, which may be important in the pathogenesis of atherosclerosis, are mediated predominantly, but not exclusively, by the p55 TNF receptor.
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Affiliation(s)
- E M Paleolog
- Kennedy Institute of Rheumatology, Sunley Division, London, UK
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Paleolog EM, Katsikis P, Harris G, Daddona P, Dalesandro MR, Kinney CS, Woody JN, Feldmann M. Antilipid A monoclonal antibody HA-1A decreases the capacity of bacterial lipopolysaccharide to activate human vascular endothelial cells by an immune adherence mechanism. Cytokine 1993; 5:570-7. [PMID: 7514452 DOI: 10.1016/s1043-4666(05)80006-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Human monoclonal IgM antibody HA-1A, which recognizes the lipid A component of bacterial lipopolysaccharide (LPS), has been shown to reduce mortality in Gram negative septicemia. The vascular endothelial lining of blood vessels, which controls leucocyte traffic and activation, as well as haemostatic balance, may be one of the primary targets of LPS action during sepsis. In earlier studies we have described HA-1A-induced immune adherence of LPS to complement receptors on erythrocytes, and showed that pre-incubation with HA-1A, in the presence of complement and red blood cells, markedly reduced LPS-induced cytokine production from peripheral blood mononuclear cells. In the present study, we measured the effect of immune adherence of LPS in the presence of HA-1A on the responses of cultured endothelial cells, and found that subsequent expression of adhesion molecules such as E-selectin, ICAM-1 and VCAM-1, and secretion of the cytokines interleukin-6 and granulocyte-macrophage colony stimulating factor were markedly reduced. Moreover, the ability of LPS to increase levels of tissue factor procoagulant activity on endothelial cells was markedly diminished by LPS immune adherence to HA-1A. This decrease in endothelial activation in response to LPS following immune adherence to HA-1A may play a significant role in the protective effect of HA-1A in vivo during the course of Gram negative sepsis.
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Affiliation(s)
- E M Paleolog
- Kennedy Institute of Rheumatology, Sunley Division, London, UK
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Paleolog EM, Aluri GR, Feldmann M. Contrasting effects of interferon gamma and interleukin 4 on responses of human vascular endothelial cells to tumour necrosis factor alpha. Cytokine 1992; 4:470-8. [PMID: 1284034 DOI: 10.1016/1043-4666(92)90007-e] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Tumour necrosis factor alpha (TNF-alpha) and interleukin 4 (IL-4) selectively synergise in inducing expression of the mononuclear cell adhesion receptor VCAM-1 (vascular cell adhesion molecule-1) on human umbilical vein endothelial cells (HUVEC), which results in increased adhesiveness of HUVEC for T lymphocytes. This process may be crucial for adherence of circulating lymphocytes prior to their passage from the blood into inflammatory tissues. IL-4 also amplifies production of interleukin 6 (IL-6) and monocyte chemotactic protein-(MCP-1) from TNF-alpha-activated HUVEC. In the present study we demonstrate that IL-4 enhances production of granulocyte-macrophage colony-stimulating factor (GM-CSF) from TNF-alpha-stimulated HUVEC. Moreover, using cultured adult saphenous vein and umbilical artery endothelial cells, we show identical effects of IL-4 on TNF-alpha-induced responses to those observed with endothelial cells of foetal origin. Additionally, we report here that TNF-alpha and interferon gamma (IFN-gamma) synergise in the induction of both the lymphocyte adhesion receptor VCAM-1, and the TNF-alpha-inducible neutrophil adhesion receptor intercellular adhesion molecule-1, on all three endothelial cell types studied. In contrast, we found that GM-CSF secretion by endothelial cells treated with IFN-gamma plus TNF-alpha was markedly decreased when compared to the response induced by TNF-alpha alone. These results suggest that the combined actions of several cytokines, acting sequentially or in concert, may exert differential effects on activation and accumulation of circulating lymphocytes at sites of inflammation.
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Affiliation(s)
- E M Paleolog
- Kennedy Institute of Rheumatology, Sunley Division, London, UK
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Carew MA, Paleolog EM, Pearson JD. The roles of protein kinase C and intracellular Ca2+ in the secretion of von Willebrand factor from human vascular endothelial cells. Biochem J 1992; 286 ( Pt 2):631-5. [PMID: 1530595 PMCID: PMC1132946 DOI: 10.1042/bj2860631] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Secretion of von Willebrand factor (vWf) glycoprotein from storage granules in human umbilical-vein endothelial cells was studied in vitro. Either elevation of intracellular Ca2+ concentration ([Ca2+]i) with a Ca2+ ionophore or activation of protein kinase (PK) C by phorbol 12-myristate 13-acetate caused vWf secretion, and together the agents acted synergistically. However, when vWf release was stimulated by receptor-mediated agonists, selective inhibition of PKC had no effect on histamine-induced secretion and significantly elevated thrombin-induced secretion. Furthermore, ATP, which efficiently elevates [Ca2+]i in these cells, was a very poor effector of vWf release. We conclude that elevation of [Ca2+]i by physiological agonists is necessary for vWf release, but other signalling mechanisms, as yet uncharacterized, but not due to PKC activation, are required for full induction of the secretory pathway.
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Affiliation(s)
- M A Carew
- Section of Vascular Biology, MRC Clinical Research Centre, Harrow, Middx., U.K
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Paleolog EM, Carew MA, Pearson JD. Effects of tumour necrosis factor and interleukin-1 on von Willebrand factor secretion from human vascular endothelial cells. Int J Radiat Biol 1991; 60:279-85. [PMID: 1677983 DOI: 10.1080/09553009114552011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- E M Paleolog
- Section of Vascular Biology, MRC Clinical Research Centre, Harrow, Middlesex UK
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Paleolog EM, Crossman DC, McVey JH, Pearson JD. Differential regulation by cytokines of constitutive and stimulated secretion of von Willebrand factor from endothelial cells. Blood 1990; 75:688-95. [PMID: 2105107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We examined the effect of cytokines on basal and agonist-stimulated release of von Willebrand factor (vWf) by human endothelial cells. Treatment of endothelial cells for up to 48 hours with human recombinant or purified interleukin 1 (IL-1) or human recombinant tumor necrosis factor-alpha (TNF-alpha) did not significantly affect constitutive secretion of vWf or intracellular levels of vWf, although basal prostacyclin (PGI2) production was markedly enhanced. In contrast, both IL-1 and TNF-alpha modulated vWf release in response to thrombin or phorbol ester. Pretreatment of endothelial cells for 2 hours with either cytokine enhanced by up to threefold the stimulatory effect of a subsequent 60-minute exposure to thrombin. Addition of cycloheximide (5 micrograms/mL) during the preincubation abolished this enhancement. Moreover, if the cytokine pretreatment time was extended to 24 hours, agonist-stimulated vWf release was significantly suppressed. Cytokine treatment for 2 or 24 hours had no detectable effect on levels of vWf messenger RNA. The effects of cytokines were not the result of contamination with bacterial lipopolysaccharide and were not attributable to endothelial cell injury. These results show that cytokines have little or no direct effect on vWf release from endothelial cells but can significantly modulate its acute release in response to other stimuli in a complex time- and dose-dependent manner.
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Affiliation(s)
- E M Paleolog
- Section of Vascular Biology, MRC Clinical Research Centre, Harrow, Middlesex, England
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