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Wang D, Chen Y, Li J, Wu E, Tang T, Singla RK, Shen B, Zhang M. Natural products for the treatment of age-related macular degeneration. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 130:155522. [PMID: 38820665 DOI: 10.1016/j.phymed.2024.155522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 02/08/2024] [Accepted: 03/07/2024] [Indexed: 06/02/2024]
Abstract
BACKGROUND Age-related macular degeneration (AMD) is a chronic retinal disease that significantly influences the vision of the elderly. PURPOSE There is no effective treatment and prevention method. The pathogenic process behind AMD is complex, including oxidative stress, inflammation, and neovascularization. It has been demonstrated that several natural products can be used to manage AMD, but systematic summaries are lacking. STUDY DESIGN AND METHODS PubMed, Web of Science, and ClinicalTrials.gov were searched using the keywords "Biological Products" AND "Macular Degeneration" for studies published within the last decade until May 2023 to summarize the latest findings on the prevention and treatment of age-related macular degeneration through the herbal medicines and functional foods. RESULTS The eligible studies were screened, and the relevant information about the therapeutic action and mechanism of natural products used to treat AMD was extracted. Our findings demonstrate that natural substances, including retinol, phenols, and other natural products, prevent the development of new blood vessels and protect the retina from oxidative stress in cells and animal models. However, they have barely been examined in clinical studies. CONCLUSION Natural products could be highly prospective candidate drugs used to treat AMD, and further preclinical and clinical research is required to validate it to control the disease.
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Affiliation(s)
- Dongyue Wang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, Sichuan, PR China
| | - Yi Chen
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, Sichuan, PR China
| | - Jiakun Li
- Department of Urology, Institute of Urology, West China Hospital, Sichuan University, Chengdu, Sichuan, PR China; Joint Laboratory of Artificial Intelligence for Critical Care Medicine, Department of Critical Care Medicine and Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, PR China
| | - Erman Wu
- Joint Laboratory of Artificial Intelligence for Critical Care Medicine, Department of Critical Care Medicine and Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, PR China
| | - Tong Tang
- Joint Laboratory of Artificial Intelligence for Critical Care Medicine, Department of Critical Care Medicine and Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, PR China
| | - Rajeev K Singla
- Joint Laboratory of Artificial Intelligence for Critical Care Medicine, Department of Critical Care Medicine and Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, PR China; School of Pharmaceutical Sciences, Lovely Professional University, Phagwara, Punjab-144411, India.
| | - Bairong Shen
- Joint Laboratory of Artificial Intelligence for Critical Care Medicine, Department of Critical Care Medicine and Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, PR China.
| | - Ming Zhang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, Sichuan, PR China.
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Zhao Q, Lai K. Role of immune inflammation regulated by macrophage in the pathogenesis of age-related macular degeneration. Exp Eye Res 2024; 239:109770. [PMID: 38145794 DOI: 10.1016/j.exer.2023.109770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/05/2023] [Accepted: 12/20/2023] [Indexed: 12/27/2023]
Abstract
Age-related macular degeneration (AMD) can lead to irreversible impairment of visual function, and the number of patients with AMD has been increasing globally. The immunoinflammatory theory is an important pathogenic mechanism of AMD, with macrophages serving as the primary inflammatory infiltrating cells in AMD lesions. Its powerful immunoinflammatory regulatory function has attracted considerable attention. Herein, we provide an overview of the involvement of macrophage-regulated immunoinflammation in different stages of AMD. Additionally, we summarize novel therapeutic approaches for AMD, focusing on targeting macrophages, such as macrophage/microglia modulators, reduction of macrophage aggregation in the subretinal space, modulation of macrophage effector function, macrophage phenotypic alterations, and novel biomimetic nanocomposites development based on macrophage-associated functional properties. We aimed to provide a basis and reference for the further exploration of AMD pathogenesis, developmental influences, and new therapeutic approaches.
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Affiliation(s)
- Qin Zhao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, No.7 Jinsui Road, Guangzhou, 510060, China
| | - Kunbei Lai
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, No.7 Jinsui Road, Guangzhou, 510060, China.
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3
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Parsons NB, Annamalai B, Rohrer B. Regulatable Complement Inhibition of the Alternative Pathway Mitigates Wet Age-Related Macular Degeneration Pathology in a Mouse Model. Transl Vis Sci Technol 2023; 12:17. [PMID: 37462980 PMCID: PMC10362922 DOI: 10.1167/tvst.12.7.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 06/19/2023] [Indexed: 07/21/2023] Open
Abstract
Purpose Risk for developing age-related macular degeneration (AMD) is linked to an overactive complement system. In the mouse model of laser-induced choroidal neovascularization (CNV), elevated levels of complement effector molecules, including complement C3, have been identified, and the alternative pathway (AP) is required for pathology. The main soluble AP regular is complement factor H (fH). We have previously shown that AP inhibition via subretinal AAV-mediated delivery of CR2-fH using a constitutive promoter is efficacious in reducing CNV. Here we ask whether the C3 promoter (pC3) effectively drives CR2-fH bioavailability for gene therapy. Methods Truncated pC3 was used to generate plasmids pC3-mCherry/CR2-fH followed by production of corresponding AAV5 vectors. pC3 activation was determined in transiently transfected ARPE-19 cells stimulated with H2O2 or normal human serum (+/- antioxidant or humanized CR2-fH, respectively). CNV was analyzed in C57BL/6J mice treated subretinally with AAV5-pC3-mCherry/CR2-fH using imaging (optical coherence tomography [OCT] and fundus imaging), functional (electroretinography [ERG]), and molecular (protein expression) readouts. Results Modulation of pC3 in vitro is complement and oxidative stress dependent, as shown by mCherry fluorescence. AAV5-pC3-CR2-fH were identified as safe and effective using OCT and ERG. CR2-fH expression significantly reduced CNV compared to mCherry and was correlated with reduced levels of C3dg/C3d in the retinal pigment epithelium/choroid fraction. Conclusions We conclude that complement-dependent regulation of AP inhibition ameliorates AMD pathology as effectively as using a constitutive promoter. Translational Relevance The goal of anticomplement therapy is to restore homeostatic levels of complement activation, which might be more easily achievable using a self-regulating system.
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Affiliation(s)
- Nathaniel B. Parsons
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
| | | | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
- Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC, USA
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Mugisho OO, Green CR. The NLRP3 inflammasome in age-related eye disease: Evidence-based connexin hemichannel therapeutics. Exp Eye Res 2021; 215:108911. [PMID: 34958779 DOI: 10.1016/j.exer.2021.108911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/25/2021] [Accepted: 12/21/2021] [Indexed: 12/21/2022]
Abstract
The inflammasome pathway is a fundamental component of the innate immune system, playing a key role especially in chronic age-related eye diseases (AREDs). The inflammasome is of particular interest because it is a common disease pathway that once instigated, can amplify and perpetuate itself leading to chronic inflammation. With aging, it becomes more difficult to shut down inflammation after an insult but the common pathway means that a shared solution may be feasible that could be effective across multiple disease indications. This review focusses on the NLRP3 inflammasome, the most studied and characterized inflammasome in the eye. It describes the two-step signalling required for NLRP3 inflammasome complex activation, and provides evidence for its role in AREDs. In the final section, the article gives an overview of potential NLRP3 inflammasome targeting therapies, before presenting evidence for connexin hemichannel regulators as upstream blockers of inflammasome activation. These have shown therapeutic efficacy in multiple ocular disease models.
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Affiliation(s)
- Odunayo O Mugisho
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand.
| | - Colin R Green
- Department of Ophthalmology, New Zealand National Eye Centre, University of Auckland, New Zealand
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Hidalgo BA, Minniefield B, Patki A, Tanner R, Bagheri M, Tiwari HK, Arnett DK, Irvin MR. A 6-CpG validated methylation risk score model for metabolic syndrome: The HyperGEN and GOLDN studies. PLoS One 2021; 16:e0259836. [PMID: 34780523 PMCID: PMC8592434 DOI: 10.1371/journal.pone.0259836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 10/27/2021] [Indexed: 12/23/2022] Open
Abstract
There has been great interest in genetic risk prediction using risk scores in recent years, however, the utility of scores developed in European populations and later applied to non-European populations has not been successful. The goal of this study was to create a methylation risk score (MRS) for metabolic syndrome (MetS), demonstrating the utility of MRS across race groups using cross-sectional data from the Hypertension Genetic Epidemiology Network (HyperGEN, N = 614 African Americans (AA)) and the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN, N = 995 European Americans (EA)). To demonstrate this, we first selected cytosine-guanine dinucleotides (CpG) sites measured on Illumina Methyl450 arrays previously reported to be significantly associated with MetS and/or component conditions in more than one race/ethnic group (CPT1A cg00574958, PHOSPHO1 cg02650017, ABCG1 cg06500161, SREBF1 cg11024682, SOCS3 cg18181703, TXNIP cg19693031). Second, we calculated the parameter estimates for the 6 CpGs in the HyperGEN data (AA) and used the beta estimates as weights to construct a MRS in HyperGEN (AA), which was validated in GOLDN (EA). We performed association analyses using logistic mixed models to test the association between the MRS and MetS, adjusting for covariates. Results showed the MRS was significantly associated with MetS in both populations. In summary, a MRS for MetS was a strong predictor for the condition across two race groups, suggesting MRS may be useful to examine metabolic disease risk or related complications across race/ethnic groups.
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Affiliation(s)
- Bertha A. Hidalgo
- Department of Epidemiology, Ryals School of Public Health, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Bre Minniefield
- Department of Epidemiology, Ryals School of Public Health, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Amit Patki
- Department of Biostatistics, Ryals School of Public Health, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Rikki Tanner
- Department of Epidemiology, Ryals School of Public Health, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Minoo Bagheri
- Center for Precision Medicine, Vanderbilt University Medical Center, Nashville, TN, United States of America
| | - Hemant K. Tiwari
- Department of Biostatistics, Ryals School of Public Health, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Donna K. Arnett
- College of Public Health, University of Kentucky, Lexington, KY, United States of America
| | - Marguerite Ryan Irvin
- Department of Epidemiology, Ryals School of Public Health, University of Alabama at Birmingham, Birmingham, AL, United States of America
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Associations between the Complement System and Choroidal Neovascularization in Wet Age-Related Macular Degeneration. Int J Mol Sci 2020; 21:ijms21249752. [PMID: 33371261 PMCID: PMC7765894 DOI: 10.3390/ijms21249752] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/14/2020] [Accepted: 12/17/2020] [Indexed: 12/16/2022] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness affecting the elderly in the Western world. The most severe form of AMD, wet AMD (wAMD), is characterized by choroidal neovascularization (CNV) and acute vision loss. The current treatment for these patients comprises monthly intravitreal injections of anti-vascular endothelial growth factor (VEGF) antibodies, but this treatment is expensive, uncomfortable for the patient, and only effective in some individuals. AMD is a complex disease that has strong associations with the complement system. All three initiating complement pathways may be relevant in CNV formation, but most evidence indicates a major role for the alternative pathway (AP) and for the terminal complement complex, as well as certain complement peptides generated upon complement activation. Since the complement system is associated with AMD and CNV, a complement inhibitor may be a therapeutic option for patients with wAMD. The aim of this review is to (i) reflect on the possible complement targets in the context of wAMD pathology, (ii) investigate the results of prior clinical trials with complement inhibitors for wAMD patients, and (iii) outline important considerations when developing a future strategy for the treatment of wAMD.
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C5 Inhibitor Avacincaptad Pegol for Geographic Atrophy Due to Age-Related Macular Degeneration: A Randomized Pivotal Phase 2/3 Trial. Ophthalmology 2020; 128:576-586. [PMID: 32882310 DOI: 10.1016/j.ophtha.2020.08.027] [Citation(s) in RCA: 235] [Impact Index Per Article: 58.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/05/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022] Open
Abstract
PURPOSE The complement pathway may play a key role in the pathogenesis of age-related macular degeneration (AMD). The safety and efficacy of avacincaptad pegol (Zimura, IVERIC bio Inc, New York, NY), a C5 inhibitor, were assessed in participants with geographic atrophy (GA) secondary to AMD (GATHER1 Study). DESIGN International, prospective, randomized, double-masked, sham-controlled, pivotal phase 2/3 clinical trial. PARTICIPANTS A total of 286 participants with GA secondary to AMD. MAIN OUTCOME MEASURES The primary efficacy endpoint was the mean rate of change in GA over 12 months measured by fundus autofluorescence (FAF) at 3 timepoints: baseline, month 6, and month 12. RESULTS The reduction in the mean rate of GA growth (square root transformation) over 12 months was 27.4% (P = 0.0072) for the avacincaptad pegol 2 mg cohort and 27.8% (P = 0.0051) for the avacincaptad pegol 4 mg cohort compared with their corresponding sham cohorts. The results for both dose groups were statistically significant. Avacincaptad pegol was generally well tolerated after monthly administration over 12 months. There were no avacincaptad pegol-related adverse events (AEs) or inflammation. Further, there were no ocular serious AEs (SAEs) and no cases of endophthalmitis. The most frequent ocular AEs were related to the injection procedure. CONCLUSIONS Intravitreal administration of avacincaptad pegol 2 mg and 4 mg led to a significant reduction of GA growth in eyes with AMD over a 12-month period. Because C5 inhibition theoretically preserves C3 activity, it may offer additional safety advantages. A second confirmatory pivotal clinical trial is underway to confirm the efficacy and safety of avacincaptad pegol in slowing the GA growth (GATHER2 Study).
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Paraoan L, Sharif U, Carlsson E, Supharattanasitthi W, Mahmud NM, Kamalden TA, Hiscott P, Jackson M, Grierson I. Secretory proteostasis of the retinal pigmented epithelium: Impairment links to age-related macular degeneration. Prog Retin Eye Res 2020; 79:100859. [PMID: 32278708 DOI: 10.1016/j.preteyeres.2020.100859] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 03/24/2020] [Accepted: 03/26/2020] [Indexed: 12/19/2022]
Abstract
Secretory proteostasis integrates protein synthesis, processing, folding and trafficking pathways that are essential for efficient cellular secretion. For the retinal pigment epithelium (RPE), secretory proteostasis is of vital importance for the maintenance of the structural and functional integrity of apical (photoreceptors) and basal (Bruch's membrane/choroidal blood supply) sides of the environment it resides in. This integrity is achieved through functions governed by RPE secreted proteins, which include extracellular matrix modelling/remodelling, angiogenesis and immune response modulation. Impaired RPE secretory proteostasis affects not only the extracellular environment, but leads to intracellular protein aggregation and ER-stress with subsequent cell death. Ample recent evidence implicates dysregulated proteostasis as a key factor in the development of age-related macular degeneration (AMD), the leading cause of blindness in the developed world, and research aiming to characterise the roles of various proteins implicated in AMD-associated dysregulated proteostasis unveiled unexpected facets of the mechanisms involved in degenerative pathogenesis. This review analyses cellular processes unveiled by the study of the top 200 transcripts most abundantly expressed by the RPE/choroid in the light of the specialised secretory nature of the RPE. Functional roles of these proteins and the mechanisms of their impaired secretion, due to age and genetic-related causes, are analysed in relation to AMD development. Understanding the importance of RPE secretory proteostasis in relation to maintaining retinal health and how it becomes impaired in disease is of paramount importance for the development and assessment of future therapeutic advancements involving gene and cell therapies.
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Affiliation(s)
- Luminita Paraoan
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom.
| | - Umar Sharif
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Emil Carlsson
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Wasu Supharattanasitthi
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom; Department of Physiology, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Nur Musfirah Mahmud
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Tengku Ain Kamalden
- Eye Research Centre, Department of Ophthalmology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Paul Hiscott
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Malcolm Jackson
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Ian Grierson
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
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Kauppinen A, Kaarniranta K, Salminen A. Potential Role of Myeloid-Derived Suppressor Cells (MDSCs) in Age-Related Macular Degeneration (AMD). Front Immunol 2020; 11:384. [PMID: 32265903 PMCID: PMC7099658 DOI: 10.3389/fimmu.2020.00384] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 02/18/2020] [Indexed: 12/23/2022] Open
Abstract
Myeloid cells, such as granulocytes/neutrophils and macrophages, have responsibilities that include pathogen destruction, waste material degradation, or antigen presentation upon inflammation. During persistent stress, myeloid cells can remain partially differentiated and adopt immunosuppressive functions. Myeloid-derived suppressor cells (MDSCs) are primarily beneficial upon restoring homeostasis after inflammation. Because of their ability to suppress adaptive immunity, MDSCs can also ameliorate autoimmune diseases and semi-allogenic responses, e.g., in pregnancy or transplantation. However, immunosuppression is not always desirable. In certain conditions, such as cancer or chronically inflamed tissue, MDSCs prevent restorative immune responses and thereby aggravate disease progression. Age-related macular degeneration (AMD) is the most common disease in Western countries that severely threatens the central vision of aged people. The pathogenesis of this multifactorial disease is not fully elucidated, but inflammation is known to participate in both dry and wet AMD. In this paper, we provide an overview about the potential role of MDSCs in the pathogenesis of AMD.
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Affiliation(s)
- Anu Kauppinen
- Faculty of Health Sciences, School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - Kai Kaarniranta
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland.,Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland
| | - Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
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Simmons KT, Mazzilli JL, Mueller-Ortiz SL, Domozhirov AY, Garcia CA, Zsigmond EM, Wetsel RA. Complement Receptor 1 (CR1/CD35)-expressing retinal pigment epithelial cells as a potential therapy for age-related macular degeneration. Mol Immunol 2019; 118:91-98. [PMID: 31862673 DOI: 10.1016/j.molimm.2019.11.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 10/25/2019] [Accepted: 11/25/2019] [Indexed: 12/30/2022]
Abstract
The purpose of this study was to identify a membrane-bound complement inhibitor that could be overexpressed on retinal pigment epithelial cells (RPE) providing a potential therapy for age-related macular degeneration (AMD). This type of therapy may allow replacement of damaged RPE with cells that are able to limit complement activation in the retina. Complement Receptor 1 (CR1) is a membrane-bound complement inhibitor commonly found on erythrocytes and immune cells. In this study, QPCR and flow cytometry data demonstrated that CR1 is not well-expressed by RPE, indicating that its overexpression may provide extra protection from complement activation. To screen CR1 for this ability, a stable CR1-expressing ARPE19 line was created using a combination of antibiotic selection and FACS. Cell-based assays were used to demonstrate that addition of CR1 inhibited deposition of complement proteins C3b and C6 on the transfected line. In the end, this study identifies CR1 as a complement inhibitor that may be overexpressed on stem cell-derived RPE to create a potential "enhanced" cell therapy for AMD. A combination cell/complement therapy may create transplantable RPE better suited to avoid complement-mediated lysis and limit chronic inflammation in the retina.
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Affiliation(s)
- Ken T Simmons
- Brown Foundation Institute of Molecular Medicine, Research Center for Immunology and Autoimmune Diseases, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States
| | - John L Mazzilli
- Brown Foundation Institute of Molecular Medicine, Research Center for Immunology and Autoimmune Diseases, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States
| | - Stacey L Mueller-Ortiz
- Brown Foundation Institute of Molecular Medicine, Research Center for Immunology and Autoimmune Diseases, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States
| | - Aleksey Y Domozhirov
- Brown Foundation Institute of Molecular Medicine, Research Center for Immunology and Autoimmune Diseases, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States
| | - Charles A Garcia
- Department of Ophthalmology and Visual Sciences, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States
| | - Eva M Zsigmond
- Brown Foundation Institute of Molecular Medicine, Research Center for Immunology and Autoimmune Diseases, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States
| | - Rick A Wetsel
- Brown Foundation Institute of Molecular Medicine, Research Center for Immunology and Autoimmune Diseases, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX, 77030, United States.
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11
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Liu K, Ma L, Lai TYY, Brelen ME, Tam POS, Tham CC, Pang CP, Chen LJ. Evaluation of the association of C5 with neovascular age-related macular degeneration and polypoidal choroidal vasculopathy. EYE AND VISION (LONDON, ENGLAND) 2019; 6:34. [PMID: 31720301 PMCID: PMC6836349 DOI: 10.1186/s40662-019-0161-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 10/17/2019] [Indexed: 12/12/2022]
Abstract
Background Neovascular age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) are sight-threatening maculopathies with both environmental and genetic risk factors. We have previously shown relative risks posed by genes of the complement pathways to neovascular AMD and PCV. Methods In this study, we investigated the haplotype-tagging single nucleotide polymorphisms (SNPs) in the complement component 5 (C5) gene in 708 unrelated Chinese individuals: 200 neovascular AMD patients, 233 PCV patients and 275 controls. Six tagging SNPs in C5 were genotyped. Univariate single SNP association analysis, haplotype-based association analysis and gene-gene interaction analysis between C5 and other AMD-associated genes were performed. Results The results revealed none of the six tagging SNPs of the C5 gene had a significant association with neovascular AMD or PCV (P > 0.05). We also found insignificant haplotype-based association, and no significant SNP-SNP interaction between C5 and other genes (including C2-CFB-RDBP-SKIV2L, SERPING1, CETP, ABCG1, PGF, ANGPT2, CFH and HTRA1) for neovascular AMD and PCV. Conclusions This study showed no statistical significance in the genetic association of C5 with neovascular AMD or PCV in a Hong Kong Chinese population. Further studies in large samples from different populations are warranted to elucidate the role of C5 in the genetic susceptibility of AMD and PCV.
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Affiliation(s)
- Ke Liu
- 1Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Li Ma
- 1Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Timothy Y Y Lai
- 1Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Marten E Brelen
- 1Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China.,2Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong, China
| | - Pancy O S Tam
- 1Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Clement C Tham
- 1Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Chi Pui Pang
- 1Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Li Jia Chen
- 1Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China.,2Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong, China
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12
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Trakkides TO, Schäfer N, Reichenthaler M, Kühn K, Brandwijk RJMGE, Toonen EJM, Urban F, Wegener J, Enzmann V, Pauly D. Oxidative Stress Increases Endogenous Complement-Dependent Inflammatory and Angiogenic Responses in Retinal Pigment Epithelial Cells Independently of Exogenous Complement Sources. Antioxidants (Basel) 2019; 8:antiox8110548. [PMID: 31766295 PMCID: PMC6928869 DOI: 10.3390/antiox8110548] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/30/2019] [Accepted: 11/11/2019] [Indexed: 12/18/2022] Open
Abstract
Oxidative stress-induced damage of the retinal pigment epithelium (RPE) and chronic inflammation have been suggested as major contributors to a range of retinal diseases. Here, we examined the effects of oxidative stress on endogenous complement components and proinflammatory and angiogenic responses in RPE cells. ARPE-19 cells exposed for 1–48 h to H2O2 had reduced cell–cell contact and increased markers for epithelial–mesenchymal transition but showed insignificant cell death. Stressed ARPE-19 cells increased the expression of complement receptors CR3 (subunit CD11b) and C5aR1. CD11b was colocalized with cell-derived complement protein C3, which was present in its activated form in ARPE-19 cells. C3, as well as its regulators complement factor H (CFH) and properdin, accumulated in the ARPE-19 cells after oxidative stress independently of external complement sources. This cell-associated complement accumulation was accompanied by increased nlrp3 and foxp3 expression and the subsequently enhanced secretion of proinflammatory and proangiogenic factors. The complement-associated ARPE-19 reaction to oxidative stress, which was independent of exogenous complement sources, was further augmented by the poly(ADP-ribose) polymerase (PARP) inhibitor olaparib. Our results indicate that ARPE-19 cell-derived complement proteins and receptors are involved in ARPE-19 cell homeostasis following oxidative stress and should be considered as targets for treatment development for retinal degeneration.
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Affiliation(s)
- Timon-Orest Trakkides
- Experimental Ophthalmology, Eye clinic, University Hospital Regensburg, 93053 Regensburg, Germany; (T.-O.T.); (N.S.); (M.R.); (K.K.)
| | - Nicole Schäfer
- Experimental Ophthalmology, Eye clinic, University Hospital Regensburg, 93053 Regensburg, Germany; (T.-O.T.); (N.S.); (M.R.); (K.K.)
| | - Maria Reichenthaler
- Experimental Ophthalmology, Eye clinic, University Hospital Regensburg, 93053 Regensburg, Germany; (T.-O.T.); (N.S.); (M.R.); (K.K.)
| | - Konstanze Kühn
- Experimental Ophthalmology, Eye clinic, University Hospital Regensburg, 93053 Regensburg, Germany; (T.-O.T.); (N.S.); (M.R.); (K.K.)
| | | | - Erik J. M. Toonen
- R&D Department, Hycult Biotech, 5405 PD Uden, The Netherlands; (R.J.M.G.E.B.); (E.J.M.T.)
| | - Florian Urban
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053 Regensburg, Germany; (F.U.); (J.W.)
| | - Joachim Wegener
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, 93053 Regensburg, Germany; (F.U.); (J.W.)
| | - Volker Enzmann
- Department of Ophthalmology, University Hospital of Bern and Department of Biomedical Research, University of Bern, 3010 Bern, Switzerland;
| | - Diana Pauly
- Experimental Ophthalmology, Eye clinic, University Hospital Regensburg, 93053 Regensburg, Germany; (T.-O.T.); (N.S.); (M.R.); (K.K.)
- Correspondence: ; Tel.: +49-941-944-9228
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13
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Bouwens van der Vlis TAM, Kros JM, Mustafa DAM, van Wijck RTA, Ackermans L, van Hagen PM, van der Spek PJ. The complement system in glioblastoma multiforme. Acta Neuropathol Commun 2018; 6:91. [PMID: 30208949 PMCID: PMC6134703 DOI: 10.1186/s40478-018-0591-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 08/29/2018] [Indexed: 12/21/2022] Open
Abstract
The human complement system is represents the main effector arm of innate immunity and its ambivalent function in cancer has been subject of ongoing dispute. Glioma stem-like cells (GSC) residing in specific niches within glioblastomas (GBM) are capable of self-renewal and tumor proliferation. Recent data are indicative of the influence of the complement system on the maintenance of these cells. It appears that the role of the complement system in glial tumorigenesis, particularly its influence on GSC niches and GSC maintenance, is significant and warrants further exploration for therapeutic interventions.
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14
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Toomey CB, Landowski M, Klingeborn M, Kelly U, Deans J, Dong H, Harrabi O, Van Blarcom T, Yeung YA, Grishanin R, Lin JC, Saban DR, Bowes Rickman C. Effect of Anti-C5a Therapy in a Murine Model of Early/Intermediate Dry Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci 2018; 59:662-673. [PMID: 29392311 PMCID: PMC5795897 DOI: 10.1167/iovs.17-23134] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Purpose A large body of evidence supports a central role for complement activation in the pathobiology of age-related macular degeneration (AMD), including plasma complement component 5a (C5a). Interestingly, C5a is a chemotactic agent for monocytes, a cell type also shown to contribute to AMD. However, the role monocytes play in the pathogenesis of “dry” AMD and the pharmacologic potential of targeting C5a to regulate these cells are unclear. We addressed these questions via C5a blockade in a unique model of early/intermediate dry AMD and large panel flow cytometry to immunophenotype monocytic involvement. Methods Heterozygous complement factor H (Cfh+/−) mice aged to 90 weeks were fed a high-fat, cholesterol-enriched diet (Cfh+/−∼HFC) for 8 weeks and were given weekly intraperitoneal injections of 30 mg/kg anti-C5a (4C9, Pfizer). Flow cytometry, retinal pigmented epithelium (RPE) flat mounts, and electroretinograms were used to characterize anti-C5a treatment. Results Aged Cfh+/− mice developed RPE damage, sub-RPE basal laminar deposits, and attenuation of visual function and immune cell recruitment to the choroid that was accompanied by expression of inflammatory and extracellular matrix remodeling genes following 8 weeks of HFC diet. Concomitant systemic administration of an anti-C5a antibody successfully inhibited local recruitment of mononuclear phagocytes to the choroid–RPE interface but did not ameliorate these AMD-like pathologies in this mouse model. Conclusions These results show that immunotherapy targeting C5a is not sufficient to block the development of the AMD-like pathologies observed in Cfh+/−∼HFC mice and suggest that other complement components or molecules/mechanisms may be driving “early” and “intermediate” AMD pathologies.
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Affiliation(s)
- Christopher B Toomey
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States.,Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, United States.,Shiley Eye Institute, Department of Ophthalmology, University of California-San Diego, San Diego, California, United States
| | - Michael Landowski
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States
| | - Mikael Klingeborn
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States
| | - Una Kelly
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States
| | - John Deans
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States
| | - Holly Dong
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | - Ons Harrabi
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | | | - Yik Andy Yeung
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | - Ruslan Grishanin
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | - John C Lin
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | - Daniel R Saban
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States.,Department of Immunology, Duke University Medical Center, Durham, North Carolina, United States
| | - Catherine Bowes Rickman
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States.,Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, United States
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15
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Jo DH, Kim JH, Yang W, Kim H, Chang S, Kim D, Chang M, Lee K, Chung J, Kim JH. Anti-complement component 5 antibody targeting MG4 domain inhibits choroidal neovascularization. Oncotarget 2018; 8:45506-45516. [PMID: 28477014 PMCID: PMC5542204 DOI: 10.18632/oncotarget.17221] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/15/2017] [Indexed: 12/27/2022] Open
Abstract
Age-related macular degeneration (AMD) is one of the main causes of visual impairment in adults. Visual deterioration is more prominent in neovascular AMD with choroidal neovascularization (CNV). Clinical and postmortem studies suggested that complement system activation might induce CNV. In this study, we demonstrated that an anti-mouse complement component 5 (C5) antibody targeting MG4 domain of β chain effectively inhibited CNV which was induced by laser photocoagulation in mice. The targeted epitope of this anti-C5 antibody was different from that of currently utilized anti-C5 antibody (eculizumab) in the MG7 domain in which a single nucleotide polymorphism (R885H/C) results in poor response to eculizumab. Even with targeting MG4 domain, this anti-C5 antibody reduced production of C5a, monocyte chemoattractant protein-1 and vascular endothelial growth factor to prevent infiltration of F4/80-positive cells into CNV lesions and formation of CNV. Furthermore, anti-C5 antibody targeting MG4 domain induced no definite toxicity in normal retina. These results demonstrated that anti-C5 antibody targeting MG4 domain inhibited CNV in neovascular AMD.
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Affiliation(s)
- Dong Hyun Jo
- Fight Against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea.,Department of Biomedical Sciences and Protein Metabolism, Medical Research Center, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jin Hyoung Kim
- Fight Against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - Wonjun Yang
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul, Republic of Korea.,Department of Cancer Biology, Seoul National University College of Medicine, Seoul, Republic of Korea.,Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hyori Kim
- Asan Institute for Life Sciences, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea
| | - Shinjae Chang
- Biotechnology Research Institute, Celltrion, Inc., Incheon, Republic of Korea
| | - Dongjo Kim
- Biotechnology Research Institute, Celltrion, Inc., Incheon, Republic of Korea
| | - Minseok Chang
- Biotechnology Research Institute, Celltrion, Inc., Incheon, Republic of Korea
| | - Kihwang Lee
- Department of Ophthalmology, Ajou University School of Medicine, Suwon, Republic of Korea
| | - Junho Chung
- Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul, Republic of Korea.,Department of Cancer Biology, Seoul National University College of Medicine, Seoul, Republic of Korea.,Cancer Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jeong Hun Kim
- Fight Against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea.,Department of Biomedical Sciences and Protein Metabolism, Medical Research Center, Seoul National University College of Medicine, Seoul, Republic of Korea.,Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea
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16
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Anaphylatoxin Signaling in Retinal Pigment and Choroidal Endothelial Cells: Characteristics and Relevance to Age-Related Macular Degeneration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1074:45-51. [PMID: 29721926 DOI: 10.1007/978-3-319-75402-4_6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness in the USA. Polymorphisms in various complement components are associated with an increased risk for AMD, and it has been hypothesized that an overactive complement system is partially responsible for the pathology of AMD. AMD is classified as early, intermediate, or late AMD, depending on the degree of the associated pathologies. Late AMD can be characterized as either lesions associated with neovascular AMD or geographic atrophy. Both sets of lesions are associated with pathology at the RPE/choroid interface, which include a thickening of Bruch's membrane, presence of drusen, and pigmentary alterations, and deterioration of the blood-retina barrier has been reported. These changes can lead to the slow degeneration and atrophy of the photoreceptors in the macula in dry AMD, or progress to choroidal neovascularization (CNV) and leakage of these new vessels in wet AMD. It has been shown previously that complement anaphylatoxins C3a and C5a, signaling via their respective G-protein-coupled receptors, can alter RPE cell function and promote choroidal neovascularization. However, it is important to note these components also play a role in tissue repair. Here we discuss anaphylatoxin signaling in AMD-related target cells and the potential implications for the design of anti-complement therapeutics.
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17
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Busch C, Annamalai B, Abdusalamova K, Reichhart N, Huber C, Lin Y, Jo EAH, Zipfel PF, Skerka C, Wildner G, Diedrichs-Möhring M, Rohrer B, Strauß O. Anaphylatoxins Activate Ca 2+, Akt/PI3-Kinase, and FOXO1/FoxP3 in the Retinal Pigment Epithelium. Front Immunol 2017; 8:703. [PMID: 28663750 PMCID: PMC5472091 DOI: 10.3389/fimmu.2017.00703] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 05/31/2017] [Indexed: 12/20/2022] Open
Abstract
PURPOSE The retinal pigment epithelium (RPE) is a main target for complement activation in age-related macular degeneration (AMD). The anaphylatoxins C3a and C5a have been thought to mostly play a role as chemoattractants for macrophages and immune cells; here, we explore whether they trigger RPE alterations. Specifically, we investigated the RPE as a potential immunoregulatory gate, allowing for active changes in the RPE microenvironment in response to complement. DESIGN In vitro and in vivo analysis of signaling pathways. METHODS Individual activities of and interaction between the two anaphylatoxin receptors were tested in cultured RPE cells by fluorescence microscopy, western blot, and immunohistochemistry. MAIN OUTCOME MEASURES Intracellular free calcium, protein phosphorylation, immunostaining of tissues/cells, and multiplex secretion assay. RESULTS Similar to immune cells, anaphylatoxin exposure resulted in increases in free cytosolic Ca2+, PI3-kinase/Akt activation, FoxP3 and FOXO1 phosphorylation, and cytokine/chemokine secretion. Differential responses were elicited depending on whether C3a and C5a were co-administered or applied consecutively, and response amplitudes in co-administration experiments ranged from additive to driven by C5a (C3a + C5a = C5a) or being smaller than those elicited by C3a alone (C3a + C5a < C3a). CONCLUSION We suggest that this combination of integrative signaling between C3aR and C5aR helps the RPE to precisely adopt its immune regulatory function. These data further contribute to our understanding of AMD pathophysiology.
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Affiliation(s)
- Catharina Busch
- Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany
- Berlin Institute of Health, Berlin, Germany
| | | | - Khava Abdusalamova
- Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany
| | - Nadine Reichhart
- Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany
| | - Christian Huber
- Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany
- Department of Ophthalmology, University of Heidelberg, Heidelberg, Germany
| | - Yuchen Lin
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Emeraldo A. H. Jo
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Peter F. Zipfel
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Christine Skerka
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Jena, Germany
| | - Gerhild Wildner
- Department of Ophthalmology, Section of Immunobiology, Clinic of the LMU Munich, Munich, Germany
| | - Maria Diedrichs-Möhring
- Department of Ophthalmology, Section of Immunobiology, Clinic of the LMU Munich, Munich, Germany
| | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, United States
- Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC, United States
| | - Olaf Strauß
- Department of Ophthalmology, Charité University Medicine Berlin, Berlin, Germany
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18
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C3a Increases VEGF and Decreases PEDF mRNA Levels in Human Retinal Pigment Epithelial Cells. BIOMED RESEARCH INTERNATIONAL 2016; 2016:6958752. [PMID: 27747237 PMCID: PMC5055919 DOI: 10.1155/2016/6958752] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 08/03/2016] [Accepted: 09/01/2016] [Indexed: 12/21/2022]
Abstract
Complement activation, specifically complement 3 (C3) activation and C3a generation, contributes to an imbalance between angiogenic stimulation by vascular endothelial growth factor (VEGF) and angiogenic inhibition by pigment epithelial derived factor (PEDF), leading to pathological angiogenesis. This study aimed to investigate the effects of C3a and small interfering RNA (siRNA) targeting C3 on the levels of VEGF and PEDF mRNAs in human retinal pigment epithelial (RPE) cells. ARPE-19 cells were cultured in the presence of exogenous C3a at 0.1 μM and 0.3 μM C3a for 24, 48, and 72 hours. 0.1 pmol/μL duplexes of siRNA targeting C3 were applied for C3a inhibition by transfecting ARPE-19 cells for 48 hours. RT-PCR was performed to examine the level of VEGF and PEDF mRNA. A random siRNA duplex was set for control siRNA. Results demonstrated that exogenous C3a significantly upregulated VEGF and downregulated PEDF mRNA levels in cultured ARPE-19 cells, and siRNA targeting C3 transfection reversed the above changes, significantly reducing VEGF and enhancing PEDF mRNAs level in ARPE-19 cells compared to the control. The present data provided evidence that reducing C3 activation can decreases VEGF and increase PEDF mRNA level in RPE and may serve as a potential therapy in pathological angiogenesis.
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19
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Hwang DE, Choi JM, Yang CS, Lee JJ, Heu W, Jo EK, Kim HS. Effective suppression of C5a-induced proinflammatory response using anti-human C5a repebody. Biochem Biophys Res Commun 2016; 477:1072-1077. [PMID: 27416759 DOI: 10.1016/j.bbrc.2016.07.041] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 07/08/2016] [Indexed: 01/21/2023]
Abstract
The strongest anaphylatoxin, C5a, plays a critical role in the proinflammatory responses, causing the pathogenesis of a number of inflammatory diseases including sepsis, asthma, and rheumatoid arthritis. Inhibitors of C5a thus have great potential as therapeutics for various inflammatory disorders. Herein, we present the development of a high-affinity repebody against human C5a (hC5a), which effectively suppresses the proinflammatory response. A repebody scaffold composed of leucine-rich repeat (LRR) modules was previously developed as an alternative protein scaffold. A repebody specifically binding to hC5a was selected through a phage display, and its affinity was increased up to 5 nM using modular engineering. The repebody was shown to effectively inhibit the production of C5a-induced proinflammatory cytokines by human monocytes. To obtain insight into a mode of action by the repebody, we determined its crystal structure in complex with hC5a. A structural analysis revealed that the repebody binds to the D1 and D3 regions of hC5a, overlapping several epitope residues with the hC5a receptor (hC5aR). It is thus likely that the repebody suppresses the hC5a-mediated immune response in monocytes by blocking the binding of hC5a to its receptor. The anti-hC5a repebody can be developed as a potential therapeutic for C5a-involved inflammatory diseases.
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Affiliation(s)
- Da-Eun Hwang
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Republic of Korea
| | - Jung-Min Choi
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Republic of Korea
| | - Chul-Su Yang
- Department of Molecular and Life Sciences, Hanyang University, Ansan, 15588, Republic of Korea
| | - Joong-Jae Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Republic of Korea
| | - Woosung Heu
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Republic of Korea
| | - Eun-Kyeong Jo
- Department of Microbiology, Chungnam National University College of Medicine, Daejeon, Republic of Korea
| | - Hak-Sung Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701, Republic of Korea.
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20
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Sakuma Y, Nagai T, Yoshio T, Hirohata S. Differential activation mechanisms of serum C5a in lupus nephritis and neuropsychiatric systemic lupus erythematosus. Mod Rheumatol 2016; 27:292-297. [PMID: 27319578 DOI: 10.1080/14397595.2016.1193965] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE To explore the role of C5a in the pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE) and lupus nephritis (LN). METHODS Sera were obtained from 29 patients with NPSLE, 25 with LN, 26 without NPSLE or LN [SLE alone], and 21 healthy donors. Cerebrospinal fluid (CSF) was obtained from 29 NPSLE patients. C5a and C5 were measured by ELISA. Blood-brain barrier (BBB) function was evaluated by Q albumin ([CSF albumin/serum albumin] × 103). RESULTS Serum C5a, but not C5, was significantly increased in SLE compared with healthy control. Serum C5a, but not C5, was significantly higher in NPSLE and in LN than in SLE alone. Serum C4, but not C3, was lower in LN than in NPSLE. Q albumin was significantly higher in diffuse NPSLE than in focal NPSLE, whereas there were no significant differences in CSF or serum C5a between both groups. Notably, CSF C5 and C5a were significantly correlated with Q albumin, whereas serum C5a, but not C5, appeared to be inversely correlated with Q albumin. CONCLUSION These results disclosed that serum C5a was elevated not only in NPSLE but also in LN through different mechanisms. Moreover, it is suggested that C5a might be consumed during BBB damages.
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Affiliation(s)
- Yuko Sakuma
- a Department of Rheumatology and Infectious Diseases , Kitasato University School of Medicine , Kanagawa , Japan and
| | - Tatsuo Nagai
- a Department of Rheumatology and Infectious Diseases , Kitasato University School of Medicine , Kanagawa , Japan and
| | - Taku Yoshio
- b Division of Rheumatology and Clinical Immunology , Jichi Medical University , Tochigi , Japan
| | - Shunsei Hirohata
- a Department of Rheumatology and Infectious Diseases , Kitasato University School of Medicine , Kanagawa , Japan and
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21
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Connecting the innate and adaptive immune responses in mouse choroidal neovascularization via the anaphylatoxin C5a and γδT-cells. Sci Rep 2016; 6:23794. [PMID: 27029558 PMCID: PMC4814842 DOI: 10.1038/srep23794] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 03/10/2016] [Indexed: 01/12/2023] Open
Abstract
Neovascular age-related macular degeneration (AMD) is characterized by choroidal neovascularization (CNV). An overactive complement system is associated with AMD pathogenesis, and serum pro-inflammatory cytokines, including IL-17, are elevated in AMD patients. IL-17 is produced by complement C5a-receptor-expressing T-cells. In murine CNV, infiltrating γδT- rather than Th17-cells produce the IL-17 measurable in lesioned eyes. Here we asked whether C5a generated locally in response to CNV recruits IL-17-producing T-cells to the eye. CNV lesions were generated using laser photocoagulation and quantified by imaging; T-lymphocytes were characterized by QRT-PCR. CNV resulted in an increase in splenic IL-17-producing γδT- and Th17-cells; yet in the CNV eye, only elevated levels of γδT-cells were observed. Systemic administration of anti-C5- or anti-C5a-blocking antibodies blunted the CNV-induced production of splenic Th17- and γδT-cells, reduced CNV size and eliminated ocular γδT-cell infiltration. In ARPE-19 cell monolayers, IL-17 triggered a pro-inflammatory state; and splenocyte proliferation was elevated in response to ocular proteins. Thus, we demonstrated that CNV lesions trigger a systemic immune response, augmenting local ocular inflammation via the infiltration of IL-17-producing γδT-cells, which are presumably recruited to the eye in a C5a-dependent manner. Understanding the complexity of complement-mediated pathological mechanisms will aid in the development of an AMD treatment.
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Genetic Investigation of Complement Pathway Genes in Type 2 Diabetic Retinopathy: An Inflammatory Perspective. Mediators Inflamm 2016; 2016:1313027. [PMID: 26989329 PMCID: PMC4771919 DOI: 10.1155/2016/1313027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 01/10/2016] [Accepted: 01/12/2016] [Indexed: 02/06/2023] Open
Abstract
Diabetic retinopathy (DR) has complex multifactorial pathogenesis. This study aimed to investigate the association of complement pathway genes with susceptibility to DR. Eight haplotype-tagging SNPs of SERPING1 and C5 were genotyped in 570 subjects with type 2 diabetes: 295 DR patients (138 nonproliferative DR [NPDR] and 157 proliferative DR [PDR]) and 275 diabetic controls. Among the six C5 SNPs, a marginal association was first detected between rs17611 and total DR patients (P = 0.009, OR = 0.53 for recessive model). In stratification analysis, a significant decrease in the frequencies of G allele and GG homozygosity for rs17611 was observed in PDR patients compared with diabetic controls (Pcorr = 0.032, OR = 0.65 and Pcorr = 0.016, OR = 0.37, resp.); it was linked with a disease progression. A haplotype AA defined by the major alleles of rs17611 and rs1548782 was significantly predisposed to PDR with increased risk of 1.54 (Pcorr = 0.023). Regarding other variants in C5 and SERPING1, none of the tagging SNPs had a significant association with DR and its subgroups (all P > 0.05). Our study revealed an association between DR and C5 polymorphisms with clinical significance, whereas SERPING1 is not a major genetic component of DR. Our data suggest a link of complement pathway with DR pathogenesis.
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Cao S, Wang JCC, Gao J, Wong M, To E, White VA, Cui JZ, Matsubara JA. CFH Y402H polymorphism and the complement activation product C5a: effects on NF-κB activation and inflammasome gene regulation. Br J Ophthalmol 2016; 100:713-8. [PMID: 26746578 DOI: 10.1136/bjophthalmol-2015-307213] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 12/14/2015] [Indexed: 11/04/2022]
Abstract
BACKGROUND/AIMS The Y402H polymorphism in the complement factor H (CFH) gene is an important risk factor for age-related macular degeneration (AMD). Complement activation products and proinflammatory cytokines are associated with this polymorphism at the systemic level, but less is known of the associations in the outer retina of the genotyped eye. Here we investigate complement activation products and their role in nuclear factor (NF)-κB activation and gene expression of the NLRP3 inflammasome pathway. METHODS Postmortem donor eyes were genotyped for the CFH Y402H polymorphism and assessed for complement C3a, C5a, interleukin (IL)-18 and tumour necrosis factor (TNF)-α. ARPE19 cells were stimulated basolaterally with C5a or TNF-α in polarised cultures. NF-κB activation was assessed with a reporter cell line. Gene expression of inflammasome-related (NLRP3, caspase-1, IL-1β and IL-18) and classic inflammatory (IL-6 and IL-8) genes was studied. The distribution of inflammasome products, IL-1β and IL-18, was studied in postmortem donor eyes with AMD pathologies. RESULTS Eyes with the homozygous at-risk variant demonstrated higher levels of C5a, IL-18 and TNF-α in Bruch's membrane and choroid. C5a promoted NF-κB activation and upregulation of IL-18 in polarised ARPE19. TNF-α promoted NF-κB activation and gene expression of caspase-1, IL-1β, IL-18, IL-6 and IL-8, but downregulated NLRP3. In eyes with geographic atrophy, strong immunoreactivity was observed for inflammasome products IL-1β and IL-18 compared with age-matched controls. CONCLUSION The at-risk polymorphism of the CFH Y402H may contribute to AMD disease process through increased complement and NF-κB activation, and the upregulation of IL-18, a product of inflammasome activation.
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Affiliation(s)
- Sijia Cao
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jay Ching Chieh Wang
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jiangyuan Gao
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Matthew Wong
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Elliott To
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Valerie A White
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jing Z Cui
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Joanne A Matsubara
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
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Brandstetter C, Holz FG, Krohne TU. Complement Component C5a Primes Retinal Pigment Epithelial Cells for Inflammasome Activation by Lipofuscin-mediated Photooxidative Damage. J Biol Chem 2015; 290:31189-98. [PMID: 26565031 DOI: 10.1074/jbc.m115.671180] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Indexed: 12/22/2022] Open
Abstract
Complement activation, oxidative damage, and activation of the NLRP3 inflammasome have been implicated in retinal pigment epithelium (RPE) pathology in age-related macular degeneration (AMD). Following priming of RPE cells, the NLRP3 inflammasome can be activated by various stimuli such as lipofuscin-mediated photooxidative damage to lysosomal membranes. We investigated whether products of complement activation are capable of providing the priming signal for inflammasome activation in RPE cells. We found that incubation of primary human RPE cells and ARPE-19 cells with complement-competent human serum resulted in up-regulation of C5a receptor, but not C3a receptor. Furthermore, human serum induced expression of pro-IL-1β and enabled IL-1β secretion in response to lipofuscin phototoxicity, thus indicating inflammasome priming. Complement heat-inactivation, C5 depletion, and C5a receptor inhibition suppressed the priming effect of human serum whereas recombinant C5a likewise induced priming. Conditioned medium of inflammasome-activated RPE cells provided an additional priming effect that was mediated by the IL-1 receptor. These results identify complement activation product C5a as a priming signal for RPE cells that allows for subsequent inflammasome activation by stimuli such as lipofuscin-mediated photooxidative damage. This molecular pathway provides a functional link between key factors of AMD pathogenesis including lipofuscin accumulation, photooxidative damage, complement activation, and RPE degeneration and may provide novel therapeutic targets in this disease.
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Affiliation(s)
| | - Frank G Holz
- From the Department of Ophthalmology, University of Bonn, 53127 Bonn, Germany
| | - Tim U Krohne
- From the Department of Ophthalmology, University of Bonn, 53127 Bonn, Germany
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Schraufstatter IU, Khaldoyanidi SK, DiScipio RG. Complement activation in the context of stem cells and tissue repair. World J Stem Cells 2015; 7:1090-1108. [PMID: 26435769 PMCID: PMC4591784 DOI: 10.4252/wjsc.v7.i8.1090] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 07/27/2015] [Indexed: 02/06/2023] Open
Abstract
The complement pathway is best known for its role in immune surveillance and inflammation. However, its ability of opsonizing and removing not only pathogens, but also necrotic and apoptotic cells, is a phylogenetically ancient means of initiating tissue repair. The means and mechanisms of complement-mediated tissue repair are discussed in this review. There is increasing evidence that complement activation contributes to tissue repair at several levels. These range from the chemo-attraction of stem and progenitor cells to areas of complement activation, to increased survival of various cell types in the presence of split products of complement, and to the production of trophic factors by cells activated by the anaphylatoxins C3a and C5a. This repair aspect of complement biology has not found sufficient appreciation until recently. The following will examine this aspect of complement biology with an emphasis on the anaphylatoxins C3a and C5a.
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26
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Merle NS, Noe R, Halbwachs-Mecarelli L, Fremeaux-Bacchi V, Roumenina LT. Complement System Part II: Role in Immunity. Front Immunol 2015; 6:257. [PMID: 26074922 PMCID: PMC4443744 DOI: 10.3389/fimmu.2015.00257] [Citation(s) in RCA: 647] [Impact Index Per Article: 71.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 05/09/2015] [Indexed: 12/14/2022] Open
Abstract
The complement system has been considered for a long time as a simple lytic cascade, aimed to kill bacteria infecting the host organism. Nowadays, this vision has changed and it is well accepted that complement is a complex innate immune surveillance system, playing a key role in host homeostasis, inflammation, and in the defense against pathogens. This review discusses recent advances in the understanding of the role of complement in physiology and pathology. It starts with a description of complement contribution to the normal physiology (homeostasis) of a healthy organism, including the silent clearance of apoptotic cells and maintenance of cell survival. In pathology, complement can be a friend or a foe. It acts as a friend in the defense against pathogens, by inducing opsonization and a direct killing by C5b–9 membrane attack complex and by triggering inflammatory responses with the anaphylatoxins C3a and C5a. Opsonization plays also a major role in the mounting of an adaptive immune response, involving antigen presenting cells, T-, and B-lymphocytes. Nevertheless, it can be also an enemy, when pathogens hijack complement regulators to protect themselves from the immune system. Inadequate complement activation becomes a disease cause, as in atypical hemolytic uremic syndrome, C3 glomerulopathies, and systemic lupus erythematosus. Age-related macular degeneration and cancer will be described as examples showing that complement contributes to a large variety of conditions, far exceeding the classical examples of diseases associated with complement deficiencies. Finally, we discuss complement as a therapeutic target.
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Affiliation(s)
- Nicolas S Merle
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France
| | - Remi Noe
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France ; Ecole Pratique des Hautes Études (EPHE) , Paris , France
| | - Lise Halbwachs-Mecarelli
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France
| | - Veronique Fremeaux-Bacchi
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France ; Service d'Immunologie Biologique, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou , Paris , France
| | - Lubka T Roumenina
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France
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Brockmann C, Brockmann T, Dege S, Busch C, Kociok N, Vater A, Klussmann S, Strauß O, Joussen AM. Intravitreal inhibition of complement C5a reduces choroidal neovascularization in mice. Graefes Arch Clin Exp Ophthalmol 2015; 253:1695-704. [PMID: 25981118 DOI: 10.1007/s00417-015-3041-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 02/20/2015] [Accepted: 04/29/2015] [Indexed: 12/12/2022] Open
Abstract
PURPOSE To investigate the influence of complement component C5a inhibition on laser-induced choroidal neovascularization (CNV) in mice using a C5a specific L-aptamer. METHODS In C57BL/6 J mice CNV was induced by argon-laser, C5a-inhibitor (NOX-D20) was intravitreally injected in three concentrations: 0.3, 3.0, and 30 mg/ml. The unPEGylated derivate (NOX-D20001) was applied at 3.0 mg/ml; the vehicle (5 % glucose) was injected in controls. Vascular leakage was evaluated using fluorescence angiography, CNV area was examined immunohistochemically. Activated immune cells surrounding the CNV lesion and potential cytotoxicity were analyzed. RESULTS Compared to controls, CNV areas were significantly reduced after NOX-D20 injection at a concentration of 0.3 and 3.0 mg/ml (p = 0.042; p = 0.016). NOX-D20001 significantly decreased CNV leakage but not the area (p = 0.007; p = 0.276). At a concentration of 30 mg/ml, NOX-D20 did not reveal significant effects on vascular leakage or CNV area (p = 0.624; p = 0.121). The amount of CD11b positive cells was significantly reduced after treatment with 0.3 and 3.0 mg/ml NOX-D20 (p = 0.027; p = 0.002). No adverse glial cell proliferation or increased apoptosis were observed at effective dosages. CONCLUSIONS Our findings demonstrate that the targeted inhibition of complement component C5a reduces vascular leakage and neovascular area in laser-induced CNV in mice. NOX-D20 was proven to be an effective and safe agent that might be considered as a therapeutic candidate for CNV treatment. The deficiency of activated immune cells highlights promising new aspects in the pathology of choroidal neovascularization, and warrants further investigations.
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Affiliation(s)
- Claudia Brockmann
- Department of Ophthalmology, Charité - University Medicine Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.
| | - Tobias Brockmann
- Department of Ophthalmology, Charité - University Medicine Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Sabrina Dege
- Department of Ophthalmology, Charité - University Medicine Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Catharina Busch
- Department of Ophthalmology, Charité - University Medicine Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Norbert Kociok
- Department of Ophthalmology, Charité - University Medicine Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Axel Vater
- NOXXON Pharma AG, Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
| | - Sven Klussmann
- NOXXON Pharma AG, Max-Dohrn-Strasse 8-10, 10589, Berlin, Germany
| | - Olaf Strauß
- Department of Ophthalmology, Charité - University Medicine Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Antonia M Joussen
- Department of Ophthalmology, Charité - University Medicine Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
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Darling VR, Hauke RJ, Tarantolo S, Agrawal DK. Immunological effects and therapeutic role of C5a in cancer. Expert Rev Clin Immunol 2014; 11:255-63. [PMID: 25387724 DOI: 10.1586/1744666x.2015.983081] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The specific role of C5a in cancer, especially in melanoma, has yet to be determined. Differential effects of C5a could be cancer specific. In the host defense system, C5a functions to protect the body from harmful entities via a plethora of mechanisms. Yet, C5a may also serve to potentiate cancerous process. C5a facilitates cellular proliferation and regeneration by attracting myeloid-derived suppressor cells and supporting tumor promotion. In this article, we critically reviewed the properties, mechanisms of action and functions of C5a, with particular emphasis on cancer inhibition and promotion, and clinical application of such knowledge in better management of patients with cancer. Outstanding questions and future directions in regard to the function of C5a in melanoma and other cancers are discussed.
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Affiliation(s)
- Victoria R Darling
- Center for Clinical and Translational Science, Creighton University School of Medicine, Omaha, NE, USA
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29
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Yang P, Baciu P, Kerrigan BCP, Etheridge M, Sung E, Toimil BA, Berchuck JE, Jaffe GJ. Retinal pigment epithelial cell death by the alternative complement cascade: role of membrane regulatory proteins, calcium, PKC, and oxidative stress. Invest Ophthalmol Vis Sci 2014; 55:3012-21. [PMID: 24677108 DOI: 10.1167/iovs.13-13554] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
PURPOSE Retinal pigment epithelial (RPE) cell death is an important feature of the advanced forms of AMD. Complement alternative pathway (AP) activation is associated with RPE cell death in AMD. In this study, we developed a new model to initiate AP activation on RPE cells and investigated the cellular mechanisms modulating AP activation-mediated RPE cell death. METHODS An anti-RPE antibody was developed. A spontaneously arising human RPE cell line (ARPE-19) and donor RPE cells were primed with this antibody followed by stimulation with 6% C1q-depleted human serum (C1q-Dep) to activate AP. Complement activation was evaluated by flow cytometry and immunofluorescent staining. Cellular response to complement activation was examined by measurement of intracellular calcium and adenosine triphosphate (ATP) release. Cell viability was assessed by Sytox orange, tetrazolium salt, and lactate dehydrogenase release assays. RESULTS Alternative pathway complement-mediated RPE cell death was associated with membrane attack complex formation and a rapid rise in intracellular calcium followed by release of ATP. Downregulation of membrane complement regulatory proteins and protein kinase C (PKC) inhibition increased cell susceptibility to complement attack. Pretreatment of RPE cells with either hydrogen peroxide or hydroquinone enhanced cell death. Chronic repetitive treatment of RPE cells with low levels of oxidants also enhanced complement-mediated cell death. CONCLUSIONS Activation of complement through the alternative pathway induces sublytic and lytic phases of complement attack on RPE cells, leading to cell death modulated by extracellular calcium, membrane complement regulatory proteins, and intracellular signaling mechanisms. Single-dose oxidant exposure and low-dose repetitive oxidant exposure rendered RPE cells more susceptible to complement-mediated death.
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Affiliation(s)
- Ping Yang
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States
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30
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Genetic and pharmacologic inhibition of complement impairs endothelial cell function and ablates ovarian cancer neovascularization. Neoplasia 2013; 14:994-1004. [PMID: 23226093 DOI: 10.1593/neo.121262] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 09/21/2012] [Accepted: 09/27/2012] [Indexed: 12/16/2022] Open
Abstract
Complement activation plays a critical role in controlling inflammatory responses. To assess the role of complement during ovarian cancer progression, we crossed two strains of mice with genetic complement deficiencies with transgenic mice that develop epithelial ovarian cancer (TgMISIIR-TAg). TgMISIIR-TAg mice fully or partially deficient for complement factor 3 (C3) (Tg(+)C3(KO) and Tg(+)C3(HET), respectively) or fully deficient for complement factor C5a receptor (C5aR) (Tg(+)C5aR(KO)) develop either no ovarian tumors or tumors that were small and poorly vascularized compared to wild-type littermates (Tg(+)C3(WT), Tg(+)C5aR(WT)). The percentage of tumor infiltrating immune cells in Tg(+)C3(HET) tumors compared to Tg(+)C3(WT) controls was either similar (macrophages, B cells, myeloid-derived suppressor cells), elevated (effector T cells), or decreased (regulatory T cells). Regardless of these ratios, cytokine production by immune cells taken from Tg(+)C3(HET) tumors was reduced on stimulation compared to Tg(+)C3(WT) controls. Interestingly, CD31(+) endothelial cell (EC) function in angiogenesis was significantly impaired in both C3(KO) and C5aR(KO) mice. Further, using the C5aR antagonist PMX53, tube formation of ECs was shown to be C5a-dependent, possibly through interactions with the VEGF(165) but not VEGF(121) isoform. Finally, the mouse VEGF(164) transcript was underexpressed in C3(KO) livers compare to C3(WT) livers. Thus, we conclude that complement inhibition blocks tumor outgrowth by altering EC function and VEGF(165) expression.
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31
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Miller JW. Age-related macular degeneration revisited--piecing the puzzle: the LXIX Edward Jackson memorial lecture. Am J Ophthalmol 2013; 155:1-35.e13. [PMID: 23245386 DOI: 10.1016/j.ajo.2012.10.018] [Citation(s) in RCA: 180] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 10/19/2012] [Accepted: 10/23/2012] [Indexed: 12/11/2022]
Abstract
PURPOSE To present the current understanding of age-related macular degeneration (AMD) pathogenesis, based on clinical evidence, epidemiologic data, histopathologic examination, and genetic data; to provide an update on current and emerging therapies; and to propose an integrated model of the pathogenesis of AMD. DESIGN Review of published clinical and experimental studies. METHODS Analysis and synthesis of clinical and experimental data. RESULTS We are closer to a complete understanding of the pathogenesis of AMD, having progressed from clinical observations to epidemiologic observations and clinical pathologic correlation. More recently, modern genetic and genomic studies have facilitated the exploration of molecular pathways. It seems that AMD is a complex disease that results from the interaction of genetic susceptibility with aging and environmental factors. Disease progression also seems to be driven by a combination of genetic and environmental factors. CONCLUSIONS Therapies based on pathophysiologic features have changed the paradigm for treating neovascular AMD. With improved understanding of the underlying genetic susceptibility, we can identify targets to halt early disease and to prevent progression and vision loss.
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Muramatsu D, Wakabayashi Y, Usui Y, Okunuki Y, Kezuka T, Goto H. Correlation of complement fragment C5a with inflammatory cytokines in the vitreous of patients with proliferative diabetic retinopathy. Graefes Arch Clin Exp Ophthalmol 2012; 251:15-7. [PMID: 22527328 DOI: 10.1007/s00417-012-2024-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 03/05/2012] [Accepted: 03/26/2012] [Indexed: 02/07/2023] Open
Abstract
PURPOSE To determine the vitreous concentration of complement fragment C5a in patients with proliferative diabetic retinopathy (PDR) and the relation between C5a and inflammatory cytokines including vascular endothelial growth factor (VEGF) and monocyte chemotactic protein-1 (MCP-1). METHODS Vitreous samples were obtained at the time of vitrectomy from 12 eyes of 11 PDR patients and from 11 eyes of 11 patients without diabetes with macular disease (controls). Vitreous and serum concentrations of human C5a, VEGF, and MCP-1 were quantified using FACS Caliber flow cytometer. RESULTS Vitreous concentration of C5a increased significantly in patients with PDR [median (range): 928.7 (46.6 to 3,319.4) pg/ml] compared with controls [58.7 (22.2 to 1,432.4) pg/ml; p < 0.01]. In PDR patients, vitreous concentration of C5a correlated significantly with those of VEGF (p < 0.05) and MCP-1 (p < 0.05). CONCLUSIONS Our results suggest that C5a may play an important role in the pathogenesis of PDR and work in concert with inflammatory cytokines such as VEGF and MCP-1 in pathological angiogenesis.
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Affiliation(s)
- Daisuke Muramatsu
- Department of Ophthalmology, Tokyo Medical University, 6-7-1, Nishishinjuku, Shinjuku-ku, Tokyo 160-0023, Japan
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Khandhadia S, Cipriani V, Yates JRW, Lotery AJ. Age-related macular degeneration and the complement system. Immunobiology 2011; 217:127-46. [PMID: 21868123 DOI: 10.1016/j.imbio.2011.07.019] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2011] [Revised: 06/22/2011] [Accepted: 07/18/2011] [Indexed: 11/30/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world. It is a complex multifactorial disease, and despite new advances in treatment, many patients still succumb to visual impairment. The complement pathway has been implicated in the pathogenesis of many diseases, and recently variants in several genes encoding complement pathway proteins have been associated with AMD. Complement proteins have been found in histological specimens of eyes with AMD. Altered levels of both intrinsic complement proteins and activated products have been found in the circulation of patients with AMD. Complement activation may be triggered by oxidative stress, resulting from retinal exposure to incoming light; indeed an inter-play between these two pathological processes seems to exist. Finally, complement inhibitors are currently being evaluated in clinical trials. This article reviews the role of the complement system in AMD, and the potential of complement inhibition in preventing the devastating blindness resulting from this disease.
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Affiliation(s)
- S Khandhadia
- Clinical Neurosciences Division, University of Southampton, UK
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Lueck K, Wasmuth S, Williams J, Hughes TR, Morgan BP, Lommatzsch A, Greenwood J, Moss SE, Pauleikhoff D. Sub-lytic C5b-9 induces functional changes in retinal pigment epithelial cells consistent with age-related macular degeneration. Eye (Lond) 2011; 25:1074-82. [PMID: 21597483 DOI: 10.1038/eye.2011.109] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
PURPOSE There is evidence for complement dysfunction in age-related macular degeneration (AMD). Complement activation leads to formation of the membrane attack complex (MAC), known to assemble on retinal pigment epithelial (RPE) cells. Therefore, the effect of sub-lytic MAC on RPE cells was examined with regard to pro-inflammatory or pro-angiogenic mediators relevant in AMD. METHODS For sub-lytic MAC induction, RPE cells were incubated with an antiserum to complement regulatory protein CD59, followed by normal human serum (NHS) to induce 5% cell death, measured by a viability assay. MAC formation was evaluated by immunofluorescence and FACS analysis. Interleukin (IL)-6, -8, monocytic chemoattractant protein-1 (MCP-1), and vascular endothelial growth factor (VEGF) were quantified by enzyme-linked immunosorbent assay (ELISA). Intracellular MCP-1 was analysed by immunofluorescence, vitronectin by western blotting, and gelatinolytic matrix metalloproteinases (MMPs) by zymography. RESULTS Incubation of RPE cells with the CD59 antiserum followed by 5% NHS induced sub-lytic amounts of MAC, verified by FACS and immunofluorescence. This treatment stimulated the cells to release IL-6, -8, MCP-1, and VEGF. MCP-1 staining, production of vitronectin, and gelatinolytic MMPs were also elevated in response to sub-lytic MAC. CONCLUSIONS MAC assembly on RPE cells increases the IL-6, -8, and MCP-1 production. Therefore, sub-lytic MAC might have a significant role in generating a pro-inflammatory microenvironment, contributing to the development of AMD. Enhanced vitronectin might be a protective mechanism against MAC deposition. In addition, the increased expression of gelatinolytic MMPs and pro-angiogenic VEGF may be associated with neovascular processes and late AMD.
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Affiliation(s)
- K Lueck
- Ophtha-Lab at Department of Ophthalmology, St Franziskus Hospital, Muenster, Germany
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35
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Lockington D, Imrie F, Gillen J, Fitzpatrick A, Willison H. Visual improvement in established central retinal vein occlusion with long-standing macular edema following systemic eculizumab treatment. Can J Ophthalmol 2010; 45:649. [DOI: 10.3129/i10-060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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Yin H, Gao L, Shen B, Chao L, Chao J. Kallistatin inhibits vascular inflammation by antagonizing tumor necrosis factor-alpha-induced nuclear factor kappaB activation. Hypertension 2010; 56:260-7. [PMID: 20566960 DOI: 10.1161/hypertensionaha.110.152330] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Kallistatin is a plasma protein with anti-inflammatory properties. In this study, we investigated the role and mechanisms of kallistatin in inhibiting endothelial inflammation through its heparin-binding domain. We showed that recombinant wild-type kallistatin dose-dependently competed with tumor necrosis factor (TNF)-alpha binding to TNF-alpha receptor in endothelial cells, whereas kallistatin mutant at the heparin-binding domain had no effect. Kallistatin, but not kallistatin mutant at the heparin-binding domain, abrogated TNF-alpha-induced endothelial cell activation, as evidenced by inhibition of TNF receptor 1-associated death domain protein activation, inhibitor of nuclear factor kappaB-alpha degradation, nuclear factor kappaB translocation, and p38 mitogen-activated protein kinase phosphorylation, as well as cell adhesion molecule and cytokine expression. Moreover, kallistatin, but not kallistatin mutant at the heparin-binding domain, inhibited TNF-alpha-induced human monocytic THP-1 cell adhesion to endothelial cells and prevented vascular endothelial growth factor-induced endothelial permeability. In mice, kallistatin gene delivery prevented vascular leakage provoked by complement factor C5a, whereas delivery of kallistatin heparin mutant gene had no effect. Similarly, gene transfer of kallistatin, but not the kallistatin heparin mutant, inhibited collagen/adjuvant-induced arthritis in rats. These results indicate that kallistatin's heparin-binding site plays an essential role in preventing TNF-alpha-mediated endothelial activation and reducing vascular endothelial growth factor-induced vascular permeability, resulting in attenuation of vascular inflammation in cultured endothelial cells and animal models. This study identifies a protective role of kallistatin in vascular injury, thereby implicating the therapeutic potential of kallistatin for vascular and inflammatory diseases.
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Affiliation(s)
- Hang Yin
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
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The spectrum of phenotypes caused by variants in the CFH gene. Mol Immunol 2009; 46:1573-94. [PMID: 19297022 DOI: 10.1016/j.molimm.2009.02.013] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2008] [Revised: 02/09/2009] [Accepted: 02/11/2009] [Indexed: 12/24/2022]
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