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Abstract
The complement cascade comprises soluble and cell surface proteins and is an important arm of the innate immune system. Once activated, the complement system rapidly generates large quantities of protein fragments that are potent mediators of inflammatory, vasoactive and metabolic responses. Although complement is crucial to host defence and homeostasis, its inappropriate or uncontrolled activation can also drive tissue injury. For example, the complement system has been known for more than 50 years to be activated by glomerular immune complexes and to contribute to autoimmune kidney disease. Notably, the latest research shows that complement is also activated in kidney diseases that are not traditionally thought of as immune-mediated, including haemolytic-uraemic syndrome, diabetic kidney disease and focal segmental glomerulosclerosis. Several complement-targeted drugs have been approved for the treatment of kidney disease, and additional anti-complement agents are being investigated in clinical trials. These drugs are categorically different from other immunosuppressive agents and target pathological processes that are not effectively inhibited by other classes of immunosuppressants. The development of these new drugs might therefore have considerable benefits in the treatment of kidney disease.
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Affiliation(s)
- Vojtech Petr
- Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Joshua M Thurman
- University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
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2
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Golshayan D, Schwotzer N, Fakhouri F, Zuber J. Targeting the Complement Pathway in Kidney Transplantation. J Am Soc Nephrol 2023; 34:1776-1792. [PMID: 37439664 PMCID: PMC10631604 DOI: 10.1681/asn.0000000000000192] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 07/02/2023] [Indexed: 07/14/2023] Open
Abstract
The complement system is paramount in the clearance of pathogens and cell debris, yet is increasingly recognized as a key component in several pathways leading to allograft injury. There is thus a growing interest in new biomarkers to assess complement activation and guide tailored therapies after kidney transplantation (KTx). C5 blockade has revolutionized post-transplant management of atypical hemolytic uremic syndrome, a paradigm of complement-driven disease. Similarly, new drugs targeting the complement amplification loop hold much promise in the treatment and prevention of recurrence of C3 glomerulopathy. Although unduly activation of the complement pathway has been described after brain death and ischemia reperfusion, any clinical attempts to mitigate the ensuing renal insults have so far provided mixed results. However, the intervention timing, strategy, and type of complement blocker need to be optimized in these settings. Furthermore, the fast-moving field of ex vivo organ perfusion technology opens new avenues to deliver complement-targeted drugs to kidney allografts with limited iatrogenic risks. Complement plays also a key role in the pathogenesis of donor-specific ABO- and HLA-targeted alloantibodies. However, C5 blockade failed overall to improve outcomes in highly sensitized patients and prevent the progression to chronic antibody-mediated rejection (ABMR). Similarly, well-conducted studies with C1 inhibitors in sensitized recipients yielded disappointing results so far, in part, because of subtherapeutic dosage used in clinical studies. The emergence of new complement blockers raises hope to significantly reduce the negative effect of ischemia reperfusion, ABMR, and nephropathy recurrence on outcomes after KTx.
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Affiliation(s)
- Dela Golshayan
- Transplantation Center, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Nora Schwotzer
- Service of Nephrology and Hypertension, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Fadi Fakhouri
- Service of Nephrology and Hypertension, Department of Medicine, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Julien Zuber
- Service de Transplantation rénale adulte, Assistance Publique-Hôpitaux de Paris, Hôpital Necker, Paris, France
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3
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Gibson B, Connelly C, Moldakhmetova S, Sheerin NS. Complement activation and kidney transplantation; a complex relationship. Immunobiology 2023; 228:152396. [PMID: 37276614 DOI: 10.1016/j.imbio.2023.152396] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/14/2023] [Accepted: 05/15/2023] [Indexed: 06/07/2023]
Abstract
Although kidney transplantation is the best treatment for end stage kidney disease, the benefits are limited by factors such as the short fall in donor numbers, the burden of immunosuppression and graft failure. Although there have been improvements in one-year outcomes, the annual rate of graft loss beyond the first year has not significantly improved, despite better therapies to control the alloimmune response. There is therefore a need to develop alternative strategies to limit kidney injury at all stages along the transplant pathway and so improve graft survival. Complement is primarily part of the innate immune system, but is also known to enhance the adaptive immune response. There is increasing evidence that complement activation occurs at many stages during transplantation and can have deleterious effects on graft outcome. Complement activation begins in the donor and occurs again on reperfusion following a period of ischemia. Complement can contribute to the development of the alloimmune response and may directly contribute to graft injury during acute and chronic allograft rejection. The complexity of the relationship between complement activation and allograft outcome is further increased by the capacity of the allograft to synthesise complement proteins, the contribution complement makes to interstitial fibrosis and complement's role in the development of recurrent disease. The better we understand the role played by complement in kidney transplant pathology the better placed we will be to intervene. This is particularly relevant with the rapid development of complement therapeutics which can now target different the different pathways of the complement system. Combining our basic understanding of complement biology with preclinical and observational data will allow the development and delivery of clinical trials which have best chance to identify any benefit of complement inhibition.
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Affiliation(s)
- B Gibson
- Clinical and Translational Research Institute Faculty of Medical Sciences, Newcastle University Newcastle upon Tyne, NE2 4HH, UK
| | - C Connelly
- Clinical and Translational Research Institute Faculty of Medical Sciences, Newcastle University Newcastle upon Tyne, NE2 4HH, UK
| | - S Moldakhmetova
- Clinical and Translational Research Institute Faculty of Medical Sciences, Newcastle University Newcastle upon Tyne, NE2 4HH, UK
| | - N S Sheerin
- Clinical and Translational Research Institute Faculty of Medical Sciences, Newcastle University Newcastle upon Tyne, NE2 4HH, UK.
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4
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West EE, Kemper C. Complosome - the intracellular complement system. Nat Rev Nephrol 2023:10.1038/s41581-023-00704-1. [PMID: 37055581 PMCID: PMC10100629 DOI: 10.1038/s41581-023-00704-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/10/2023] [Indexed: 04/15/2023]
Abstract
The complement system is a recognized pillar of host defence against infection and noxious self-derived antigens. Complement is traditionally known as a serum-effective system, whereby the liver expresses and secretes most complement components, which participate in the detection of bloodborne pathogens and drive an inflammatory reaction to safely remove the microbial or antigenic threat. However, perturbations in normal complement function can cause severe disease and, for reasons that are currently not fully understood, the kidney is particularly vulnerable to dysregulated complement activity. Novel insights into complement biology have identified cell-autonomous and intracellularly active complement - the complosome - as an unexpected central orchestrator of normal cell physiology. For example, the complosome controls mitochondrial activity, glycolysis, oxidative phosphorylation, cell survival and gene regulation in innate and adaptive immune cells, and in non-immune cells, such as fibroblasts and endothelial and epithelial cells. These unanticipated complosome contributions to basic cell physiological pathways make it a novel and central player in the control of cell homeostasis and effector responses. This discovery, together with the realization that an increasing number of human diseases involve complement perturbations, has renewed interest in the complement system and its therapeutic targeting. Here, we summarize the current knowledge about the complosome across healthy cells and tissues, highlight contributions from dysregulated complosome activities to human disease and discuss potential therapeutic implications.
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Affiliation(s)
- Erin E West
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Complement and Inflammation Research Section (CIRS), Bethesda, MD, USA
| | - Claudia Kemper
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Complement and Inflammation Research Section (CIRS), Bethesda, MD, USA.
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5
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Kale A, Rogers NM. No Time to Die-How Islets Meet Their Demise in Transplantation. Cells 2023; 12:cells12050796. [PMID: 36899932 PMCID: PMC10000424 DOI: 10.3390/cells12050796] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/27/2023] [Accepted: 03/01/2023] [Indexed: 03/08/2023] Open
Abstract
Islet transplantation represents an effective treatment for patients with type 1 diabetes mellitus (T1DM) and severe hypoglycaemia unawareness, capable of circumventing impaired counterregulatory pathways that no longer provide protection against low blood glucose levels. The additional beneficial effect of normalizing metabolic glycaemic control is the minimisation of further complications related to T1DM and insulin administration. However, patients require allogeneic islets from up to three donors, and the long-term insulin independence is inferior to that achieved with solid organ (whole pancreas) transplantation. This is likely due to the fragility of islets caused by the isolation process, innate immune responses following portal infusion, auto- and allo-immune-mediated destruction and β-cell exhaustion following transplantation. This review covers the specific challenges related to islet vulnerability and dysfunction that affect long-term cell survival following transplantation.
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Affiliation(s)
- Atharva Kale
- Centre for Transplant and Renal Research, Westmead Institute for Medical Research, Westmead, NSW 2145, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
| | - Natasha M. Rogers
- Centre for Transplant and Renal Research, Westmead Institute for Medical Research, Westmead, NSW 2145, Australia
- Faculty of Medicine and Health, University of Sydney, Sydney, NSW 2006, Australia
- Renal and Transplant Unit, Westmead Hospital, Westmead, NSW 2145, Australia
- Correspondence:
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Thurman JM, Harrison RA. The susceptibility of the kidney to alternative pathway activation-A hypothesis. Immunol Rev 2023; 313:327-338. [PMID: 36369971 DOI: 10.1111/imr.13168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The glomerulus is often the prime target of dysregulated alternative pathway (AP) activation. In particular, AP activation is the key driver of two severe kidney diseases: atypical hemolytic uremic syndrome and C3 glomerulopathy. Both conditions are associated with a variety of predisposing molecular defects in AP regulation, such as genetic variants in complement regulators, autoantibodies targeting AP proteins, or autoantibodies that stabilize the AP convertases (C3- and C5-activating enzymes). It is noteworthy that these are systemic AP defects, yet in both diseases pathologic complement activation primarily affects the kidneys. In particular, AP activation is often limited to the glomerular capillaries. This tropism of AP-mediated inflammation for the glomerulus points to a unique interaction between AP proteins in plasma and this particular anatomic structure. In this review, we discuss the pre-clinical and clinical data linking the molecular causes of aberrant control of the AP with activation in the glomerulus, and the possible causes of this tropism. Based on these data, we propose a model for why the kidney is so uniquely and frequently targeted in patients with AP defects. Finally, we discuss possible strategies for preventing pathologic AP activation in the kidney.
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Affiliation(s)
- Joshua M Thurman
- Department of Medicine, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
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7
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Delaura IF, Gao Q, Anwar IJ, Abraham N, Kahan R, Hartwig MG, Barbas AS. Complement-targeting therapeutics for ischemia-reperfusion injury in transplantation and the potential for ex vivo delivery. Front Immunol 2022; 13:1000172. [PMID: 36341433 PMCID: PMC9626853 DOI: 10.3389/fimmu.2022.1000172] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 10/05/2022] [Indexed: 01/21/2023] Open
Abstract
Organ shortages and an expanding waitlist have led to increased utilization of marginal organs. All donor organs are subject to varying degrees of IRI during the transplant process. Extended criteria organs, including those from older donors and organs donated after circulatory death are especially vulnerable to ischemia-reperfusion injury (IRI). Involvement of the complement cascade in mediating IRI has been studied extensively. Complement plays a vital role in the propagation of IRI and subsequent recruitment of the adaptive immune elements. Complement inhibition at various points of the pathway has been shown to mitigate IRI and minimize future immune-mediated injury in preclinical models. The recent introduction of ex vivo machine perfusion platforms provides an ideal window for therapeutic interventions. Here we review the role of complement in IRI by organ system and highlight potential therapeutic targets for intervention during ex vivo machine preservation of donor organs.
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Affiliation(s)
- Isabel F. Delaura
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Qimeng Gao
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Imran J. Anwar
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Nader Abraham
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Riley Kahan
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
| | - Matthew G. Hartwig
- Division of Cardiovascular and Thoracic Surgery, Duke University Medical Center, Durham, NC, United States
| | - Andrew S. Barbas
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
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Song G, Wang S, Barkestani MN, Mullan C, Fan M, Jiang B, Jiang Q, Li X, Jane-wit D. Membrane attack complexes, endothelial cell activation, and direct allorecognition. Front Immunol 2022; 13:1020889. [PMID: 36211400 PMCID: PMC9539657 DOI: 10.3389/fimmu.2022.1020889] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 09/07/2022] [Indexed: 11/18/2022] Open
Abstract
Endothelial cells (ECs) form a critical immune interface regulating both the activation and trafficking of alloreactive T cells. In the setting of solid organ transplantation, donor-derived ECs represent sites where alloreactive T cells encounter major and minor tissue-derived alloantigens. During this initial encounter, ECs may formatively modulate effector responses of these T cells through expression of inflammatory mediators. Direct allorecognition is a process whereby recipient T cells recognize alloantigen in the context of donor EC-derived HLA molecules. Direct alloresponses are strongly modulated by human ECs and are galvanized by EC-derived inflammatory mediators. Complement are immune proteins that mark damaged or foreign surfaces for immune cell activation. Following labeling by natural IgM during ischemia reperfusion injury (IRI) or IgG during antibody-mediated rejection (ABMR), the complement cascade is terminally activated in the vicinity of donor-derived ECs to locally generate the solid-phase inflammatory mediator, the membrane attack complex (MAC). Via upregulation of leukocyte adhesion molecules, costimulatory molecules, and cytokine trans-presentation, MAC strengthen EC:T cell direct alloresponses and qualitatively shape the alloimmune T cell response. These processes together promote T cell-mediated inflammation during solid organ transplant rejection. In this review we describe molecular pathways downstream of IgM- and IgG-mediated MAC assembly on ECs in the setting of IRI and ABMR of tissue allografts, respectively. We describe work demonstrating that MAC deposition on ECs generates ‘signaling endosomes’ that sequester and post-translationally enhance the stability of inflammatory signaling molecules to promote EC activation, a process potentiating EC-mediated direct allorecognition. Additionally, with consideration to first-in-human xenotransplantation procedures, we describe clinical therapeutics based on inhibition of the complement pathway. The complement cascade critically mediates EC activation and improved understanding of relevant effector pathways will uncover druggable targets to obviate dysregulated alloimmune T cell infiltration into tissue allografts.
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Affiliation(s)
- Guiyu Song
- Section of Cardiovascular Medicine, Dept of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Shaoxun Wang
- Section of Cardiovascular Medicine, Dept of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
- Department of Surgery, Yale University School of Medicine, New Haven, CT, United States
| | - Mahsa Nouri Barkestani
- Section of Cardiovascular Medicine, Dept of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Clancy Mullan
- Department of Surgery, Yale University School of Medicine, New Haven, CT, United States
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, United States
| | - Matthew Fan
- Section of Cardiovascular Medicine, Dept of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Bo Jiang
- Department of Surgery, Yale University School of Medicine, New Haven, CT, United States
- Department of Vascular Surgery, The First Hospital of China Medical University, Shenyang, China
| | - Quan Jiang
- Section of Cardiovascular Medicine, Dept of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
| | - Xue Li
- Section of Cardiovascular Medicine, Dept of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
- Department of Nephrology, The First Hospital of China Medical University, Shenyang, China
| | - Dan Jane-wit
- Section of Cardiovascular Medicine, Dept of Internal Medicine, Yale University School of Medicine, New Haven, CT, United States
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, United States
- Department of Cardiology, West Haven VA Medical Center, West Haven, CT, United States
- *Correspondence: Dan Jane-wit,
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9
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Yan LL, Ye LP, Chen YH, He SQ, Zhang CY, Mao XL, Li SW. The Influence of Microenvironment on Survival of Intraportal Transplanted Islets. Front Immunol 2022; 13:849580. [PMID: 35418988 PMCID: PMC8995531 DOI: 10.3389/fimmu.2022.849580] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 03/03/2022] [Indexed: 12/21/2022] Open
Abstract
Clinical islet transplantation has the potential to cure type 1 diabetes. Despite recent therapeutic success, it is still uncommon because transplanted islets are damaged by multiple challenges, including instant blood mediated inflammatory reaction (IBMIR), inflammatory cytokines, hypoxia/reperfusion injury, and immune rejection. The transplantation microenvironment plays a vital role especially in intraportal islet transplantation. The identification and targeting of pathways that function as "master regulators" during deleterious inflammatory events after transplantation, and the induction of immune tolerance, are necessary to improve the survival of transplanted islets. In this article, we attempt to provide an overview of the influence of microenvironment on the survival of transplanted islets, as well as possible therapeutic targets.
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Affiliation(s)
- Ling-ling Yan
- Key Laboratory of Minimally Invasive Techniques & Rapid Rehabilitation of Digestive System Tumor of Zhejiang Province, Taizhou Hospital Affiliated to Wenzhou Medical University, Linhai, China
- Department of Gastroenterology, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
| | - Li-ping Ye
- Key Laboratory of Minimally Invasive Techniques & Rapid Rehabilitation of Digestive System Tumor of Zhejiang Province, Taizhou Hospital Affiliated to Wenzhou Medical University, Linhai, China
- Department of Gastroenterology, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
- Institute of Digestive Disease, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
| | - Ya-hong Chen
- Health Management Center, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
| | - Sai-qin He
- Department of Gastroenterology, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
| | - Chen-yang Zhang
- Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
| | - Xin-li Mao
- Key Laboratory of Minimally Invasive Techniques & Rapid Rehabilitation of Digestive System Tumor of Zhejiang Province, Taizhou Hospital Affiliated to Wenzhou Medical University, Linhai, China
- Department of Gastroenterology, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
- Institute of Digestive Disease, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
| | - Shao-wei Li
- Key Laboratory of Minimally Invasive Techniques & Rapid Rehabilitation of Digestive System Tumor of Zhejiang Province, Taizhou Hospital Affiliated to Wenzhou Medical University, Linhai, China
- Department of Gastroenterology, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
- Institute of Digestive Disease, Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University, Linhai, China
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Kamel MH, Jaberi A, Gordon CE, Beck LH, Francis J. The Complement System in the Modern Era of Kidney Transplantation: Mechanisms of Injury and Targeted Therapies. Semin Nephrol 2022; 42:14-28. [DOI: 10.1016/j.semnephrol.2022.01.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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11
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Freiwald T, Afzali B. Renal diseases and the role of complement: Linking complement to immune effector pathways and therapeutics. Adv Immunol 2021; 152:1-81. [PMID: 34844708 PMCID: PMC8905641 DOI: 10.1016/bs.ai.2021.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The complement system is an ancient and phylogenetically conserved key danger sensing system that is critical for host defense against pathogens. Activation of the complement system is a vital component of innate immunity required for the detection and removal of pathogens. It is also a central orchestrator of adaptive immune responses and a constituent of normal tissue homeostasis. Once complement activation occurs, this system deposits indiscriminately on any cell surface in the vicinity and has the potential to cause unwanted and excessive tissue injury. Deposition of complement components is recognized as a hallmark of a variety of kidney diseases, where it is indeed associated with damage to the self. The provenance and the pathophysiological role(s) played by complement in each kidney disease is not fully understood. However, in recent years there has been a renaissance in the study of complement, with greater appreciation of its intracellular roles as a cell-intrinsic system and its interplay with immune effector pathways. This has been paired with a profusion of novel therapeutic agents antagonizing complement components, including approved inhibitors against complement components (C)1, C3, C5 and C5aR1. A number of clinical trials have investigated the use of these more targeted approaches for the management of kidney diseases. In this review we present and summarize the evidence for the roles of complement in kidney diseases and discuss the available clinical evidence for complement inhibition.
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Affiliation(s)
- Tilo Freiwald
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Bethesda, MD, United States; Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany
| | - Behdad Afzali
- Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany.
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12
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Witczak BJ, Pischke SE, Reisæter AV, Midtvedt K, Ludviksen JK, Heldal K, Jenssen T, Hartmann A, Åsberg A, Mollnes TE. Elevated Terminal C5b-9 Complement Complex 10 Weeks Post Kidney Transplantation Was Associated With Reduced Long-Term Patient and Kidney Graft Survival. Front Immunol 2021; 12:738927. [PMID: 34759922 PMCID: PMC8573334 DOI: 10.3389/fimmu.2021.738927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 10/04/2021] [Indexed: 11/25/2022] Open
Abstract
Background The major reason for graft loss is chronic tissue damage, as interstitial fibrosis and tubular atrophy (IF/TA), where complement activation may serve as a mediator. The association of complement activation in a stable phase early after kidney transplantation with long-term outcomes is unexplored. Methods We examined plasma terminal C5b-9 complement complex (TCC) 10 weeks posttransplant in 900 patients receiving a kidney between 2007 and 2012. Clinical outcomes were assessed after a median observation time of 9.3 years [interquartile range (IQR) 7.5–10.6]. Results Elevated TCC plasma values (≥0.7 CAU/ml) were present in 138 patients (15.3%) and associated with a lower 10-year patient survival rate (65.7% vs. 75.5%, P < 0.003). Similarly, 10-year graft survival was lower with elevated TCC; 56.9% vs. 67.3% (P < 0.002). Graft survival was also lower when censored for death; 81.5% vs. 87.3% (P = 0.04). In multivariable Cox analyses, impaired patient survival was significantly associated with elevated TCC [hazard ratio (HR) 1.40 (1.02–1.91), P = 0.04] along with male sex, recipient and donor age, smoking, diabetes, and overall survival more than 1 year in renal replacement therapy prior to engraftment. Likewise, elevated TCC was independently associated with graft loss [HR 1.40 (1.06–1.85), P = 0.02] along with the same covariates. Finally, elevated TCC was in addition independently associated with death-censored graft loss [HR 1.69 (1.06–2.71), P = 0.03] as were also HLA-DR mismatches and higher immunological risk. Conclusions Early complement activation, assessed by plasma TCC, was associated with impaired long-term patient and graft survival.
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Affiliation(s)
| | - Søren E Pischke
- Department of Immunology, Oslo University Hospital, University of Oslo, Oslo, Norway.,Department of Anaesthesiology, Oslo University Hospital-Rikshospitalet, Oslo, Norway
| | - Anna V Reisæter
- Department of Transplantation Medicine, Oslo University Hospital-Rikshospitalet, Oslo, Norway.,Norwegian Renal Registry, Oslo University Hospital-Rikshospitalet, Oslo, Norway
| | - Karsten Midtvedt
- Department of Transplantation Medicine, Oslo University Hospital-Rikshospitalet, Oslo, Norway
| | | | - Kristian Heldal
- Department of Transplantation Medicine, Oslo University Hospital-Rikshospitalet, Oslo, Norway
| | - Trond Jenssen
- Department of Transplantation Medicine, Oslo University Hospital-Rikshospitalet, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Anders Hartmann
- Department of Transplantation Medicine, Oslo University Hospital-Rikshospitalet, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Anders Åsberg
- Department of Transplantation Medicine, Oslo University Hospital-Rikshospitalet, Oslo, Norway.,Norwegian Renal Registry, Oslo University Hospital-Rikshospitalet, Oslo, Norway.,Department of Pharmacy, University of Oslo, Oslo, Norway
| | - Tom E Mollnes
- Department of Immunology, Oslo University Hospital, University of Oslo, Oslo, Norway.,Research Laboratory, Nordland Hospital, Bodø, Norway.,Faculty of Health Sciences, KG Jebsen Thrombosis Research and Expertise Center (TREC), University of Tromsø, Tromsø, Norway.,Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway
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13
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van Leeuwen LL, Spraakman NA, Brat A, Huang H, Thorne AM, Bonham S, van Balkom BWM, Ploeg RJ, Kessler BM, Leuvenink HGD. Proteomic analysis of machine perfusion solution from brain dead donor kidneys reveals that elevated complement, cytoskeleton and lipid metabolism proteins are associated with 1-year outcome. Transpl Int 2021; 34:1618-1629. [PMID: 34448265 PMCID: PMC9292651 DOI: 10.1111/tri.13984] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/14/2021] [Accepted: 07/15/2021] [Indexed: 11/29/2022]
Abstract
Assessment of donor kidney quality is based on clinical scores or requires biopsies for histological assessment. Noninvasive strategies to identify and predict graft outcome at an early stage are, therefore, needed. We evaluated the perfusate of donation after brain death (DBD) kidneys during nonoxygenated hypothermic machine perfusion (HMP). In particular, we compared perfusate protein profiles of good outcome (GO) and suboptimal outcome (SO) 1‐year post‐transplantation. Samples taken 15 min after the start HMP (T1) and before the termination of HMP (T2) were analysed using quantitative liquid chromatography–tandem mass spectrometry (LC‐MS/MS). Hierarchical clustering of the 100 most abundant proteins showed discrimination between grafts with a GO and SO at T1. Elevated levels of proteins involved in classical complement cascades at both T1 and T2 and a reduced abundance of lipid metabolism at T1 and of cytoskeletal proteins at T2 in GO versus SO was observed. ATP‐citrate synthase and fatty acid‐binding protein 5 (T1) and immunoglobulin heavy variable 2‐26 and desmoplakin (T2) showed 91% and 86% predictive values, respectively, for transplant outcome. Taken together, DBD kidney HMP perfusate profiles can distinguish between outcome 1‐year post‐transplantation. Furthermore, it provides insights into mechanisms that could play a role in post‐transplant outcomes.
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Affiliation(s)
- L Leonie van Leeuwen
- Department of Surgery, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.,Nuffield Department of Medicine, Target Discovery Institute, Centre for Medicines Discovery, University of Oxford, Oxford, UK
| | - Nora A Spraakman
- Department of Anaesthesiology, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
| | - Aukje Brat
- Department of Surgery, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.,Nuffield Department of Medicine, Target Discovery Institute, Centre for Medicines Discovery, University of Oxford, Oxford, UK
| | - Honglei Huang
- Nuffield Department of Medicine, Target Discovery Institute, Centre for Medicines Discovery, University of Oxford, Oxford, UK.,Nuffield Department of Surgical Sciences, University of Oxford, BRC Oxford and NHS Blood and Transplant, Oxford, UK
| | - Adam M Thorne
- Department of Surgery, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.,Nuffield Department of Medicine, Target Discovery Institute, Centre for Medicines Discovery, University of Oxford, Oxford, UK
| | - Sarah Bonham
- Nuffield Department of Medicine, Target Discovery Institute, Centre for Medicines Discovery, University of Oxford, Oxford, UK
| | - Bas W M van Balkom
- Department of Nephrology and Hypertension, University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Rutger J Ploeg
- Department of Surgery, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands.,Nuffield Department of Surgical Sciences, University of Oxford, BRC Oxford and NHS Blood and Transplant, Oxford, UK
| | - Benedikt M Kessler
- Nuffield Department of Medicine, Target Discovery Institute, Centre for Medicines Discovery, University of Oxford, Oxford, UK
| | - Henri G D Leuvenink
- Department of Surgery, University of Groningen, University Medical Centre Groningen, Groningen, The Netherlands
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14
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Franzin R, Stasi A, Fiorentino M, Simone S, Oberbauer R, Castellano G, Gesualdo L. Renal Delivery of Pharmacologic Agents During Machine Perfusion to Prevent Ischaemia-Reperfusion Injury: From Murine Model to Clinical Trials. Front Immunol 2021; 12:673562. [PMID: 34295329 PMCID: PMC8290413 DOI: 10.3389/fimmu.2021.673562] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 06/21/2021] [Indexed: 12/12/2022] Open
Abstract
Donor organ shortage still remains a serious obstacle for the access of wait-list patients to kidney transplantation, the best treatment for End-Stage Kidney Disease (ESKD). To expand the number of transplants, the use of lower quality organs from older ECD or DCD donors has become an established routine but at the price of increased incidence of Primary Non-Function, Delay Graft Function and lower-long term graft survival. In the last years, several improvements have been made in the field of renal transplantation from surgical procedure to preservation strategies. To improve renal outcomes, research has focused on development of innovative and dynamic preservation techniques, in order to assess graft function and promote regeneration by pharmacological intervention before transplantation. This review provides an overview of the current knowledge of these new preservation strategies by machine perfusions and pharmacological interventions at different timing possibilities: in the organ donor, ex-vivo during perfusion machine reconditioning or after implementation in the recipient. We will report therapies as anti-oxidant and anti-inflammatory agents, senolytics agents, complement inhibitors, HDL, siRNA and H2S supplementation. Renal delivery of pharmacologic agents during preservation state provides a window of opportunity to treat the organ in an isolated manner and a crucial route of administration. Even if few studies have been reported of transplantation after ex-vivo drugs administration, targeting the biological pathway associated to kidney failure (i.e. oxidative stress, complement system, fibrosis) might be a promising therapeutic strategy to improve the quality of various donor organs and expand organ availability.
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Affiliation(s)
- Rossana Franzin
- Department of Emergency and Organ Transplantation, Nephrology, Dialysis and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy
| | - Alessandra Stasi
- Department of Emergency and Organ Transplantation, Nephrology, Dialysis and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy
| | - Marco Fiorentino
- Department of Emergency and Organ Transplantation, Nephrology, Dialysis and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy
| | - Simona Simone
- Department of Emergency and Organ Transplantation, Nephrology, Dialysis and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy
| | - Rainer Oberbauer
- Department of Nephrology and Dialysis, University Clinic for Internal Medicine III, Medical University Vienna, Vienna, Austria
| | - Giuseppe Castellano
- Nephrology, Dialysis and Transplantation Unit, Advanced Research Center on Kidney Aging (A.R.K.A.), Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Loreto Gesualdo
- Department of Emergency and Organ Transplantation, Nephrology, Dialysis and Transplantation Unit, University of Bari Aldo Moro, Bari, Italy
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15
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The Influence of Donor and Recipient Complement C3 Polymorphisms on Liver Transplant Outcome. Int J Hepatol 2021; 2021:6636456. [PMID: 34123432 PMCID: PMC8168477 DOI: 10.1155/2021/6636456] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 04/27/2021] [Indexed: 12/19/2022] Open
Abstract
Despite early reports of an impact of complement C3 polymorphism on liver transplant patient and graft survival, subsequent evidence has been conflicting. Our aim was to clarify the contributions of donor and recipient C3 genotype, separately and together, on patient and graft outcomes and acute rejection incidence in liver transplant recipients. Eight donor/recipient groups were analyzed according to their genotype and presence or absence of C3 F allele (FFFS, FFSS, FSFF, FSFS, FSSS, SSFF, SSFS, and SSSS) and correlated with clinical outcomes of patient survival, graft survival, and rejection. The further impact of brain death vs. circulatory death during liver donation was also considered. Over a median 5.3 y follow-up of 506 patients with clinical information and matching donor and recipient tissue, five-year patient and graft survival (95% confidence interval) were 90(81-91)% and 77(73-85)%, respectively, and 72(69-94)% were rejection-free. Early disadvantages to patient survival were associated with donor C3 F variant, especially in brain-death donors. Recipient C3 genotype was an independent determinant of graft survival by Cox proportional hazards analysis (hazard ratio 0.26, P = 0.04), and the C3 F donor variant was again associated with worse liver graft survival, particularly in brain-death donors. C3 genotype did not independently determine rejection incidence, but a greater proportion of recipient C3 F carriers were rejection-free in the circulatory death, but not the brain-death cohort. Cox proportional hazards analysis revealed significant effects of acute rejection on patient survival (hazard ratio 0.24, P = 0.018), of retransplantation on rejection risk (hazard ratio 6.3, P = 0.009), and of donor type (circulatory-death vs. brain-death) on rejection incidence (hazard ratio 4.9, P = 0.005). We conclude that both donor and recipient complement C3 genotype may influence patient and graft outcomes after liver transplantation but that the type of liver donor is additionally influential, possibly via the inflammatory environment of the transplant.
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16
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Kielar M, Gala-Błądzińska A, Dumnicka P, Ceranowicz P, Kapusta M, Naumnik B, Kubiak G, Kuźniewski M, Kuśnierz-Cabala B. Complement Components in the Diagnosis and Treatment after Kidney Transplantation-Is There a Missing Link? Biomolecules 2021; 11:biom11060773. [PMID: 34064132 PMCID: PMC8224281 DOI: 10.3390/biom11060773] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/14/2021] [Accepted: 05/18/2021] [Indexed: 12/25/2022] Open
Abstract
Currently, kidney transplantation is widely accepted as the renal replacement therapy allowing for the best quality of life and longest survival of patients developing end-stage renal disease. However, chronic transplant rejection, recurrence of previous kidney disease or newly acquired conditions, or immunosuppressive drug toxicity often lead to a deterioration of kidney allograft function over time. Complement components play an important role in the pathogenesis of kidney allograft impairment. Most studies on the role of complement in kidney graft function focus on humoral rejection; however, complement has also been associated with cell mediated rejection, post-transplant thrombotic microangiopathy, the recurrence of several glomerulopathies in the transplanted kidney, and transplant tolerance. Better understanding of the complement involvement in the transplanted kidney damage has led to the development of novel therapies that inhibit complement components and improve graft survival. The analysis of functional complotypes, based on the genotype of both graft recipient and donor, may become a valuable tool for assessing the risk of acute transplant rejection. The review summarizes current knowledge on the pathomechanisms of complement activation following kidney transplantation and the resulting diagnostic and therapeutic possibilities.
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Affiliation(s)
- Małgorzata Kielar
- St. Louis Regional Children’s Hospital, Medical Diagnostic Laboratory with a Bacteriology Laboratory, Strzelecka 2 St., 31-503 Kraków, Poland;
| | - Agnieszka Gala-Błądzińska
- Medical College of Rzeszów University, Institute of Medical Sciences, Kopisto 2A Avn., 35-310 Rzeszów, Poland;
| | - Paulina Dumnicka
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Medical Diagnostics, Medyczna 9 St., 30-688 Kraków, Poland;
| | - Piotr Ceranowicz
- Jagiellonian University Medical College, Faculty of Medicine, Department of Physiology, Grzegórzecka 16 St., 31-531 Kraków, Poland;
| | - Maria Kapusta
- Jagiellonian University Medical College, Faculty of Medicine, Chair of Clinical Biochemistry, Department of Diagnostics, Kopernika 15A St., 31-501 Kraków, Poland;
| | - Beata Naumnik
- Medical University of Białystok, Faculty of Medicine, 1st Department of Nephrology and Transplantation with Dialysis Unit, Żurawia 14 St., 15-540 Białystok, Poland;
| | - Grzegorz Kubiak
- Catholic University of Leuven, Department of Cardiovascular Diseases, 3000 Leuven, Belgium;
| | - Marek Kuźniewski
- Jagiellonian University Medical College, Faculty of Medicine, Chair and Department of Nephrology, Jakubowskiego 2 St., 30-688 Kraków, Poland;
| | - Beata Kuśnierz-Cabala
- Jagiellonian University Medical College, Faculty of Medicine, Chair of Clinical Biochemistry, Department of Diagnostics, Kopernika 15A St., 31-501 Kraków, Poland;
- Correspondence: ; Tel.: +48-12-424-83-65
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17
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Lo S, Jiang L, Stacks S, Lin H, Parajuli N. Aberrant activation of the complement system in renal grafts is mediated by cold storage. Am J Physiol Renal Physiol 2021; 320:F1174-F1190. [PMID: 33998295 DOI: 10.1152/ajprenal.00670.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aberrant complement activation leads to tissue damage during kidney transplantation, and it is recognized as an important target for therapeutic intervention. However, it is not clear whether cold storage (CS) triggers the complement pathway in transplanted kidneys. The goal of the present study was to determine the impact of CS on complement activation in renal transplants. Male Lewis and Fischer rats were used, and donor rat kidneys were exposed to 4 h or 18 h of CS followed by transplantation (CS + transplant). To study CS-induced effects, a group with no CS was included in which the kidney was removed and transplanted back to the same rat [autotransplantation (ATx)]. Complement proteins (C3 and C5b-9) were evaluated with Western blot analysis (reducing and nonreducing conditions) and immunostaining. Western blot analysis of renal extracts or serum indicated that the levels of C3 and C5b-9 increased after CS + transplant compared with ATx. Quite strikingly, intracellular C3 was profoundly elevated within renal tubules after CS + transplant but was absent in sham or ATx groups, which showed only extratubular C3. Similarly, C5b-9 immunofluorescence staining of renal sections showed an increase in C5b-9 deposits in kidneys after CS + transplant. Real-time PCR (SYBR green) showed increased expression of CD11b and CD11c, components of complement receptors 3 and 4, respectively, as well as inflammatory markers such as TNF-α. In addition, recombinant TNF-α significantly increased C3 levels in renal cells. Collectively, these results demonstrate that CS mediates aberrant activation of the complement system in renal grafts following transplantation.NEW & NOTEWORTHY This study highlights cold storage-mediated aberrant activation of complement components in renal allografts following transplantation. Specifically, the results demonstrate, for the first time, that cold storage functions in exacerbation of C5b-9, a terminal cytolytic membrane attack complex, in renal grafts following transplantation. In addition, the results indicated that cold storage induces local C3 biogenesis in renal proximal cells/tubules and that TNF-α promotes C3 biogenesis and activation in renal proximal tubular cells.
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Affiliation(s)
- Sorena Lo
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Li Jiang
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Savannah Stacks
- Arkansas Children's Research Institute, Little Rock, Arkansas
| | - Haixia Lin
- Arkansas Children's Nutrition Center, Little Rock, Arkansas
| | - Nirmala Parajuli
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, Arkansas
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18
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Awad SM, Taha M, Omar M, Khalil A. The implication of genetic variation in the complement C3 allotypes on the first-year allograft outcome after live donor liver transplantation. Transpl Immunol 2020; 60:101294. [PMID: 32305505 DOI: 10.1016/j.trim.2020.101294] [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: 11/27/2019] [Revised: 04/11/2020] [Accepted: 04/13/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND The component (C3) of the complement system constitutes a central element in liver transplantation. C3 is produced mainly by the liver and comprises both slow (C3-S), and fast (C3-F) components. METHODS The effect of a single nucleotide variation in the C3 gene on the first-year outcome examined by ARMS PCR in 30 recipients of living donor allograft. RESULTS Frequencies of C3-S and C3-F in the Egyptian recipients' population were 67% and 33%. C3-F allele frequency was prevalent than the C3-S allele in recipients who developed acute rejection. The C3-SF and C3-FF genotypes significantly associated with acute rejection with 6.25 times increase in the risk of rejection than C3-SS (OR: 6.25; CI:1.05-37.07, p < .05). C3-SS increases the survival 2.5 times more than C3-SF or C3-FF but without significant association (OR: 0.40, CI: 0.07-2.44, p = .3). C3 genotypes or allotypes had no significant association with the recipient's survival, death, graft loss, infection, or serum levels of tacrolimus (all p > .05). C3-FF and C3-SF genotypes had the highest HCV recurrence rate but without significant association (p > .05). CONCLUSION In liver allograft recipients, C3-SF and C3-FF genotypes significantly associated with acute rejection with the C3-F allele more prevalent than the C3-S. C3-SS genotype increases survival without significant association.
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Affiliation(s)
- Samah Mohamed Awad
- Department of Clinical Microbiology and Immunology, National Liver Institute, Menoufia University, Egypt
| | - Mohammed Taha
- Department of Hepatobiliary and Pancreatic Surgery and Gastroenterology, National Liver Institute, Menoufia University, Egypt
| | - Mahmoud Omar
- Department of Hepatology and Gastroenterology, National Liver Institute, Menoufia University, Egypt
| | - Ashraf Khalil
- Department of Clinical Biochemistry and Molecular Diagnostics, National Liver Institute, Menoufia University, Egypt.
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19
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High-activity Classical and Alternative Complement Pathway Genotypes-Association With Donor-specific Antibody-triggered Injury and Renal Allograft Survival. Transplant Direct 2020; 6:e534. [PMID: 32195325 PMCID: PMC7056277 DOI: 10.1097/txd.0000000000000978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 12/24/2019] [Indexed: 11/26/2022] Open
Abstract
Background Complement may contribute to donor-specific antibody (DSA)-triggered transplant injury. Here, we investigated whether the intrinsic strength of classical pathway and alternative pathway (AP) relates to the pathogenicity of DSA. Methods Classical pathway and AP high-activity genotypes were defined according to C4 gene copy number and the presence of functional polymorphisms in C3 (C3102G), factor B (fB32R), and factor H (fH62V) genes. Associations of these genotypes with blood complement profiles and morphologic/molecular rejection features were evaluated in a cohort of 83 DSA-positive patients (antibody-mediated rejection [AMR], n = 47) identified upon cross-sectional screening of 741 kidney allograft recipients ≥180 days posttransplantation. Associations with long-term graft survival were evaluated in a larger kidney transplant cohort (n = 660) not enriched for a specific type of rejection. Results In the cohort of DSA-positive subjects, the number of C4 gene copies was related to C4 protein levels in serum and capillary C4d staining, but not AMR activity. Patients with a high-activity AP complotype, which was associated with complement consumption in serum, showed enhanced microcirculation inflammation (median glomerulitis plus peritubular capillaritis score, 2 [interquartile range, 0-4 versus 1 0-2]; P = 0.037). In the larger transplant cohort, this complotype was associated with a slightly increased risk of graft loss (hazard ratio, 1.52; 95% confidence interval, 1.02-2.25; P = 0.038 and multivariable Cox model, 1.55; 1.04-2.32; P = 0.031). Conclusions Our study suggests a contribution of complement genetics to the phenotypic presentation of AMR. Future studies will have to clarify whether a possible association of AP strength with graft survival relates to enhanced antibody-triggered injury.
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20
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Shen Z, Lu J, Wei J, Zhao J, Wang M, Wang M, Shen X, Lü X, Zhou B, Zhao Y, Fu G. Investigation of the underlying hub genes and mechanisms of reperfusion injury in patients undergoing coronary artery bypass graft surgery by integrated bioinformatic analyses. ANNALS OF TRANSLATIONAL MEDICINE 2019; 7:664. [PMID: 31930065 DOI: 10.21037/atm.2019.10.43] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Background Although coronary artery bypass graft (CABG) surgery is the main method to revascularize the occluded coronary vessels in coronary artery diseases, the full benefits of the operation are mitigated by ischemia-reperfusion (IR) injury. Although many studies have been devoted to reducing IR injury in animal models, the translation of this research into the clinical field has been disappointing. Our study aimed to explore the underlying hub genes and mechanisms of IR injury. Methods A weighted gene co-expression network analysis (WGCNA) was executed based on the expression profiles in patients undergoing CABG surgery (GSE29396). Functional annotation and protein-protein interaction (PPI) network construction were executed within the modules of interest. Potential hub genes were predicted, combining both intramodular connectivity (IC) and degrees. Meanwhile, potential transcription factors (TFs) and microRNAs (miRNAs) were predicted by corresponding bioinformatics tools. Results A total of 336 differentially expressed genes (DEGs) were identified. DEGs were mainly enriched in neutrophil activity and immune response. Within the modules of interest, 5 upregulated hub genes (IL-6, CXCL8, IL-1β, MYC, PTGS-2) and 6 downregulated hub genes (C3, TIMP1, VSIG4, SERPING1, CD163, and HP) were predicted. Predicted miRNAs (hsa-miR-333-5p, hsa-miR-26b-5p, hsa-miR-124-3p, hsa-miR-16-5p, hsa-miR-98-5p, hsa-miR-17-5p, hsa-miR-93-5p) and TF (STAT1) might have regulated gene expression in the most positively related module, while hsa-miR-333-5p and HSF-1 were predicted to regulate the genes within the most negatively related module. Conclusions Our study illustrates an overview of gene expression changes in human atrial samples from patients undergoing CABG surgery and might help translate future research into clinical work.
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Affiliation(s)
- Zhida Shen
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Jiangting Lu
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Jiejin Wei
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China.,Department of Electrocardiogram, Shaoxing People's Hospital, Shaoxing 312000, China
| | - Juanjuan Zhao
- Biomedical Research Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Meihui Wang
- Biomedical Research Center, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Ming Wang
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Xiaohua Shen
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Xue Lü
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Binquan Zhou
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Yanbo Zhao
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
| | - Guosheng Fu
- Department of Cardiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China
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21
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Grafals M, Thurman JM. The Role of Complement in Organ Transplantation. Front Immunol 2019; 10:2380. [PMID: 31636644 PMCID: PMC6788431 DOI: 10.3389/fimmu.2019.02380] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 09/23/2019] [Indexed: 12/17/2022] Open
Abstract
The current immunosuppressive protocols used in transplant recipients have improved short-term outcomes, but long-term allograft failure remains an important clinical problem. Greater understanding of the immunologic mechanisms that cause allograft failure are needed, as well as new treatment strategies for protecting transplanted organs. The complement cascade is an important part of the innate immune system. Studies have shown that complement activation contributes to allograft injury in several clinical settings, including ischemia/reperfusion injury and antibody mediated rejection. Furthermore, the complement system plays critical roles in modulating the responses of T cells and B cells to antigens. Therapeutic complement inhibitors, therefore, may be effective for protecting transplanted organs from several causes of inflammatory injury. Although several anti-complement drugs have shown promise in selected patients, the role of these drugs in transplantation medicine requires further study.
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Affiliation(s)
- Monica Grafals
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, United States
| | - Joshua M Thurman
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, United States
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22
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Kardol-Hoefnagel T, Budding K, van de Graaf EA, van Setten J, van Rossum OA, Oudijk EJD, Otten HG. A Single Nucleotide C3 Polymorphism Associates With Clinical Outcome After Lung Transplantation. Front Immunol 2019; 10:2245. [PMID: 31616421 PMCID: PMC6775212 DOI: 10.3389/fimmu.2019.02245] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 09/04/2019] [Indexed: 12/18/2022] Open
Abstract
Background: Development of chronic rejection is still a severe problem and causes high mortality rates after lung transplantation (LTx). Complement activation is important in the development of acute rejection (AR) and bronchiolitis obliterans syndrome, with C3 as a key complement factor. Methods: We investigated a single nucleotide polymorphism (SNP) in the C3 gene (rs2230199) in relation to long-term outcome after LTx in 144 patient-donor pairs. In addition, we looked at local production of donor C3 by analyzing bronchoalveolar lavage fluid (BALF) of 6 LTx patients using isoelectric focusing (IEF). Results: We demonstrated the presence of C3 in BALF and showed that this is produced by the donor lung based on the genotype of SNP rs2230199. We also analyzed donor and patient SNP configurations and observed a significant association between the SNP configuration in patients and episodes of AR during 4-years follow-up. Survival analysis showed a lower AR-free survival in homozygous C3 slow patients (p = 0.005). Furthermore, we found a significant association between the SNP configuration in donors and BOS development. Patients receiving a graft from a donor with at least one C3 fast variant for rs2230199 had an inferior BOS-free survival (p = 0.044). Conclusions: In conclusion, our data indicate local C3 production by donor lung cells. In addition, a single C3 SNP present in recipients affects short-term outcome after LTx, while this SNP in donors has an opposite effect on long-term outcome after LTx. These results could contribute to an improved risk stratification after transplantation.
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Affiliation(s)
- Tineke Kardol-Hoefnagel
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Kevin Budding
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Eduard A van de Graaf
- Department of Respiratory Medicine, University Medical Center Utrecht, Utrecht, Netherlands
| | - Jessica van Setten
- Department of Cardiology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Oliver A van Rossum
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Erik-Jan D Oudijk
- Center of Interstitial Lung Diseases, St. Antonius Hospital, Nieuwegein, Netherlands
| | - Henderikus G Otten
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
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23
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Abstract
Increasing evidence indicates an integral role for the complement system in the deleterious inflammatory reactions that occur during critical phases of the transplantation process, such as brain or cardiac death of the donor, surgical trauma, organ preservation and ischaemia-reperfusion injury, as well as in humoral and cellular immune responses to the allograft. Ischaemia is the most common cause of complement activation in kidney transplantation and in combination with reperfusion is a major cause of inflammation and graft damage. Complement also has a prominent role in antibody-mediated rejection (ABMR) owing to ABO and HLA incompatibility, which leads to devastating damage to the transplanted kidney. Emerging drugs and treatment modalities that inhibit complement activation at various stages in the complement cascade are being developed to ameliorate the damage caused by complement activation in transplantation. These promising new therapies have various potential applications at different stages in the process of transplantation, including inhibiting the destructive effects of ischaemia and/or reperfusion injury, treating ABMR, inducing accommodation and modulating the adaptive immune response.
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24
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Kamburova EG, Hoitsma A, Claas FH, Otten HG. Results and reflections from the PROfiling Consortium on Antibody Repertoire and Effector functions in kidney transplantation: A mini-review. HLA 2019; 94:129-140. [PMID: 31099989 PMCID: PMC6772180 DOI: 10.1111/tan.13581] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 04/05/2019] [Accepted: 05/14/2019] [Indexed: 12/15/2022]
Abstract
Kidney transplantation is the best treatment option for patients with end-stage renal disease (ESRD). The waiting time for a deceased donor kidney in the Netherlands is approximately 3 years. Mortality among patients on the waiting list is high. The aim of the PROCARE consortium (PROfiling Consortium on Antibody Repertoire and Effector functions) was to decrease the waiting time by providing a matching algorithm yielding a prolonged graft survival and less HLA-immunization compared with the currently used Eurotransplant Kidney allocation system. In this study, 6097 kidney transplants carried out between January 1995 and December 2005 were re-examined with modern laboratory techniques and insights that were not available during that time period. In this way, we could identify potential new parameters that can be used to improve the matching algorithm and prolong graft survival. All eight University Medical Centers in the Netherlands participated in this multicenter study. To improve the matching algorithm, we used as central hypothesis that the combined presence of class-I and -II single-antigen bead (SAB)-defined donor-specific HLA antibodies (DSA) prior to transplantation, non-HLA antibodies, the number of B- and/or T-cell epitopes recognized on donor HLA, and specific polymorphisms in effector mechanisms of IgG were associated with an increased risk for graft failure. The purpose of this article is to relate the results obtained from the PROCARE consortium study to other studies published in recent years. The clinical relevance of SAB-defined DSA, complement-fixing DSA, non-HLA antibodies, and the effector functions of (non)-HLA-antibodies will be discussed.
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Affiliation(s)
- Elena G. Kamburova
- Laboratory of Translational Immunology, University Medical Center UtrechtUtrecht UniversityUtrechtThe Netherlands
| | - Andries Hoitsma
- Dutch Organ Transplant Registry (NOTR)Dutch Transplant Foundation (NTS)LeidenThe Netherlands
| | - Frans H. Claas
- Department of Immunohematology and Blood TransfusionLeiden University Medical CenterLeidenThe Netherlands
| | - Henny G. Otten
- Laboratory of Translational Immunology, University Medical Center UtrechtUtrecht UniversityUtrechtThe Netherlands
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van Zanden JE, Jager NM, Daha MR, Erasmus ME, Leuvenink HGD, Seelen MA. Complement Therapeutics in the Multi-Organ Donor: Do or Don't? Front Immunol 2019; 10:329. [PMID: 30873176 PMCID: PMC6400964 DOI: 10.3389/fimmu.2019.00329] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 02/08/2019] [Indexed: 12/18/2022] Open
Abstract
Over the last decade, striking progress has been made in the field of organ transplantation, such as better surgical expertise and preservation techniques. Therefore, organ transplantation is nowadays considered a successful treatment in end-stage diseases of various organs, e.g. the kidney, liver, intestine, heart, and lungs. However, there are still barriers which prevent a lifelong survival of the donor graft in the recipient. Activation of the immune system is an important limiting factor in the transplantation process. As part of this pro-inflammatory environment, the complement system is triggered. Complement activation plays a key role in the transplantation process, as highlighted by the amount of studies in ischemia-reperfusion injury (IRI) and rejection. However, new insight have shown that complement is not only activated in the later stages of transplantation, but already commences in the donor. In deceased donors, complement activation is associated with deteriorated quality of deceased donor organs. Of importance, since most donor organs are derived from either brain-dead donors or deceased after circulatory death donors. The exact mechanisms and the role of the complement system in the pathophysiology of the deceased donor have been underexposed. This review provides an overview of the current knowledge on complement activation in the (multi-)organ donor. Targeting the complement system might be a promising therapeutic strategy to improve the quality of various donor organs. Therefore, we will discuss the complement therapeutics that already have been tested in the donor. Finally, we question whether complement therapeutics should be translated to the clinics and if all organs share the same potential complement targets, considering the physiological differences of each organ.
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Affiliation(s)
- Judith E. van Zanden
- Department of Surgery, University Medical Center Groningen, Groningen, Netherlands
| | - Neeltina M. Jager
- Department of Surgery, University Medical Center Groningen, Groningen, Netherlands
| | - Mohamed R. Daha
- Department of Nephrology, Leiden University Medical Center, Leiden, Netherlands
- Division of Nephrology, Department of Internal Medicine, University Medical Center Groningen, Groningen, Netherlands
| | - Michiel E. Erasmus
- Department of Thoracic Surgery, University Medical Center Groningen, Groningen, Netherlands
| | | | - Marc A. Seelen
- Division of Nephrology, Department of Internal Medicine, University Medical Center Groningen, Groningen, Netherlands
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Omoyinmi E, Mohamoud I, Gilmour K, Brogan PA, Eleftheriou D. Cutaneous Vasculitis and Digital Ischaemia Caused by Heterozygous Gain-of-Function Mutation in C3. Front Immunol 2018; 9:2524. [PMID: 30443255 PMCID: PMC6221951 DOI: 10.3389/fimmu.2018.02524] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 10/12/2018] [Indexed: 12/22/2022] Open
Abstract
It is now increasingly recognized that some monogenic autoinflammatory diseases and immunodeficiencies cause vasculitis, although genetic causes of vasculitis are extremely rare. We describe a child of non-consanguineous parents who presented with cutaneous vasculitis, digital ischaemia and hypocomplementaemia. A heterozygous p.R1042G gain-of-function mutation (GOF) in the complement component C3 gene was identified as the cause, resulting in secondary C3 consumption and complete absence of alternative complement pathway activity, decreased classical complement activity, and low levels of serum C3 with normal C4 levels. The same heterozygous mutation and immunological defects were also identified in another symptomatic sibling and his father. C3 deficiency due GOF C3 mutations is thus now added to the growing list of monogenic causes of vasculitis and should always be considered in vasculitis patients found to have persistently low levels of C3 with normal C4.
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Affiliation(s)
- Ebun Omoyinmi
- Infection, Inflammation and Rheumatology Section, UCL Great Ormond Street Institute of Child Health, London, United Kingdom.,Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom
| | - Iman Mohamoud
- Infection, Inflammation and Rheumatology Section, UCL Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Kimberly Gilmour
- Clinical Immunology Laboratory, Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom
| | - Paul A Brogan
- Infection, Inflammation and Rheumatology Section, UCL Great Ormond Street Institute of Child Health, London, United Kingdom.,Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom
| | - Despina Eleftheriou
- Infection, Inflammation and Rheumatology Section, UCL Great Ormond Street Institute of Child Health, London, United Kingdom.,Great Ormond Street Hospital NHS Foundation Trust, London, United Kingdom.,Centre for Adolescent Rheumatology, Arthritis Research UK, University College London (UCL), University College London Hospital (UCLH) and Great Ormond Street Hospital (GOSH), London, United Kingdom
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27
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Abstract
BACKGROUND Kidneys derived from brain-dead (BD) donors have lower graft survival rates compared with kidneys from living donors. Complement activation plays an important role in brain death. The aim of our study was therefore to investigate the effect of C1-inhibitor (C1-INH) on BD-induced renal injury. METHODS Brain death was induced in rats by inflating a subdurally placed balloon catheter. Thirty minutes after BD, rats were treated with saline, low-dose or high-dose C1-INH. Sham-operated rats served as controls. After 4 hours of brain death, renal function, injury, inflammation, and complement activation were assessed. RESULTS High-dose C1-INH treatment of BD donors resulted in significantly lower renal gene expression and serum levels of IL-6. Treatment with C1-INH also improved renal function and reduced renal injury, reflected by the significantly lower kidney injury marker 1 gene expression and lower serum levels of lactate dehydrogenase and creatinine. Furthermore, C1-INH effectively reduced complement activation by brain death and significantly increased functional levels. However, C1-INH treatment did not prevent renal cellular influx. CONCLUSIONS Targeting complement activation after the induction of brain death reduced renal inflammation and improved renal function before transplantation. Therefore, strategies targeting complement activation in human BD donors might clinically improve donor organ viability and renal allograft survival.
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Hernandez‐Fuentes MP, Franklin C, Rebollo‐Mesa I, Mollon J, Delaney F, Perucha E, Stapleton C, Borrows R, Byrne C, Cavalleri G, Clarke B, Clatworthy M, Feehally J, Fuggle S, Gagliano SA, Griffin S, Hammad A, Higgins R, Jardine A, Keogan M, Leach T, MacPhee I, Mark PB, Marsh J, Maxwell P, McKane W, McLean A, Newstead C, Augustine T, Phelan P, Powis S, Rowe P, Sheerin N, Solomon E, Stephens H, Thuraisingham R, Trembath R, Topham P, Vaughan R, Sacks SH, Conlon P, Opelz G, Soranzo N, Weale ME, Lord GM. Long- and short-term outcomes in renal allografts with deceased donors: A large recipient and donor genome-wide association study. Am J Transplant 2018; 18:1370-1379. [PMID: 29392897 PMCID: PMC6001640 DOI: 10.1111/ajt.14594] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/28/2017] [Accepted: 11/13/2017] [Indexed: 01/25/2023]
Abstract
Improvements in immunosuppression have modified short-term survival of deceased-donor allografts, but not their rate of long-term failure. Mismatches between donor and recipient HLA play an important role in the acute and chronic allogeneic immune response against the graft. Perfect matching at clinically relevant HLA loci does not obviate the need for immunosuppression, suggesting that additional genetic variation plays a critical role in both short- and long-term graft outcomes. By combining patient data and samples from supranational cohorts across the United Kingdom and European Union, we performed the first large-scale genome-wide association study analyzing both donor and recipient DNA in 2094 complete renal transplant-pairs with replication in 5866 complete pairs. We studied deceased-donor grafts allocated on the basis of preferential HLA matching, which provided some control for HLA genetic effects. No strong donor or recipient genetic effects contributing to long- or short-term allograft survival were found outside the HLA region. We discuss the implications for future research and clinical application.
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Affiliation(s)
| | | | | | - Jennifer Mollon
- King's College LondonMRC Centre for TransplantationLondonUK,Department of HaematologyUniversity of Cambridge, Cambridge, UK
| | - Florence Delaney
- King's College LondonMRC Centre for TransplantationLondonUK,NIHR Biomedical Research Centre at Guy's and St Thomas’NHS Foundation Trust and King's College LondonLondonUK
| | | | | | - Richard Borrows
- Renal Institute of BirminghamDepartment of Nephrology and TransplantationBirminghamUK
| | - Catherine Byrne
- Nottingham Renal and Transplant UnitNottingham University Hospitals NHS TrustNottinghamUK
| | | | - Brendan Clarke
- Transplant and Cellular ImmunologyLeeds Teaching Hospitals NHS TrustLeedsUK
| | | | | | - Susan Fuggle
- Transplant Immunology & ImmunogeneticsChurchill HospitalOxfordUK
| | - Sarah A. Gagliano
- Center for Statistical GeneticsDepartment of BiostatisticsUniversity of MichiganAnn ArborMIUSA
| | - Sian Griffin
- Cardiff & Vale University Health BoardCardiff UniversityCardiffUK
| | - Abdul Hammad
- The Royal Liverpool and Broadgreen University HospitalsLiverpoolUK
| | - Robert Higgins
- University Hospitals Coventry and Warwickshire NHS TrustCoventryUK
| | - Alan Jardine
- School of MedicineDentistry and NursingUniversity of GlasgowGlasgowUK
| | | | | | | | - Patrick B. Mark
- School of MedicineDentistry and NursingUniversity of GlasgowGlasgowUK
| | - James Marsh
- Epsom and St Helier University Hospitals TrustCarshaltonUK
| | - Peter Maxwell
- School of MedicineDentistry and Biomedical SciencesQueens University BelfastBelfastUK
| | - William McKane
- Sheffield Kidney InstituteSheffield Teaching Hospitals NHS Foundation TrustSheffieldUK
| | - Adam McLean
- Kidney and TransplantImperial College Healthcare NHS TrustLondonUK
| | | | - Titus Augustine
- Central Manchester University Hospitals NHS TrustManchesterUK
| | | | - Steve Powis
- Division of MedicineUniversity College LondonLondonUK
| | | | - Neil Sheerin
- The Medical SchoolNewcastle University NewcastleNewcastle upon TyneUK
| | - Ellen Solomon
- Division of Genetics& Molecular MedicineKing's College LondonLondonUK
| | | | | | - Richard Trembath
- Division of Genetics& Molecular MedicineKing's College LondonLondonUK
| | | | - Robert Vaughan
- Clinical Transplantation Laboratory at Guy's HospitalGuy's and St Thomas’ NHS TrustLondonUK
| | - Steven H. Sacks
- King's College LondonMRC Centre for TransplantationLondonUK,NIHR Biomedical Research Centre at Guy's and St Thomas’NHS Foundation Trust and King's College LondonLondonUK
| | - Peter Conlon
- Royal College of Surgeons in IrelandDublinIreland,Beaumont HospitalDublinIreland
| | - Gerhard Opelz
- University of HeidelbergTransplantation ImmunologyHeidelbergGermany
| | - Nicole Soranzo
- Welcome Trust Sanger InstituteHuman GeneticsCambridgeUK,Department of HaematologyUniversity of Cambridge, Cambridge, UK
| | - Michael E. Weale
- Division of Genetics& Molecular MedicineKing's College LondonLondonUK,Present address:
Genomics plcOxfordUK
| | - Graham M. Lord
- King's College LondonMRC Centre for TransplantationLondonUK,NIHR Biomedical Research Centre at Guy's and St Thomas’NHS Foundation Trust and King's College LondonLondonUK
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Yang J, Claas FHJ, Eikmans M. Genome-wide association studies in kidney transplantation: Advantages and constraints. Transpl Immunol 2018; 49:1-4. [PMID: 29704558 DOI: 10.1016/j.trim.2018.04.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Accepted: 04/23/2018] [Indexed: 01/03/2023]
Abstract
Since the discovery of the human leukocyte antigen (HLA) system, the role of HLA molecules in the field of transplantation has been appreciated: better matching leads to better graft function. Since then, the association of other genetic polymorphisms with clinical outcome has been investigated in many studies. Genome-wide association studies (GWAS) represent a powerful tool to identify causal genetic variants, by simultaneously analyzing millions of single nucleotide polymorphisms scattered across the genome. GWAS in transplantation may indeed be useful to reveal novel markers that may potentially be involved in the mechanism of allograft rejection and graft failure. However, the relevance of GWAS for risk stratification or donor selection for an individual patient is limited as is already reflected by the fact that many parameters, significant in one study, cannot be confirmed in another one.
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Affiliation(s)
- Jianxin Yang
- Dept. of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Frans H J Claas
- Dept. of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Michael Eikmans
- Dept. of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands.
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30
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Marin AV, Cárdenas PP, Jiménez-Reinoso A, Muñoz-Ruiz M, Regueiro JR. Lymphocyte integration of complement cues. Semin Cell Dev Biol 2018; 85:132-142. [PMID: 29438807 DOI: 10.1016/j.semcdb.2018.02.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 02/08/2018] [Indexed: 12/17/2022]
Abstract
We address current data, views and puzzles on the emerging topic of regulation of lymphocytes by complement proteins or fragments. Such regulation is believed to take place through complement receptors (CR) and membrane complement regulators (CReg) involved in cell function or protection, respectively, including intracellular signalling. Original observations in B cells clearly support that complement cues through CR improve their performance. Other lymphocytes likely integrate complement-derived signals, as most lymphoid cells constitutively express or regulate CR and CReg upon activation. CR-induced signals, particularly by anaphylatoxins, clearly regulate lymphoid cell function. In contrast, data obtained by CReg crosslinking using antibodies are not always confirmed in human congenital deficiencies or knock-out mice, casting doubts on their physiological relevance. Unsurprisingly, human and mouse complement systems are not completely homologous, adding further complexity to our still fragmentary understanding of complement-lymphocyte interactions.
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Affiliation(s)
- Ana V Marin
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Paula P Cárdenas
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Anaïs Jiménez-Reinoso
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Miguel Muñoz-Ruiz
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain
| | - Jose R Regueiro
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine and 12 de Octubre Health Research Institute (imas12), Madrid, Spain.
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31
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Hilhorst M, van Paassen P, van Rie H, Bijnens N, Heerings-Rewinkel P, van Breda Vriesman P, Cohen Tervaert JW. Complement in ANCA-associated glomerulonephritis. Nephrol Dial Transplant 2018; 32:1302-1313. [PMID: 26275893 DOI: 10.1093/ndt/gfv288] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 06/23/2015] [Indexed: 12/21/2022] Open
Abstract
Background Anti-neutrophil cytoplasmic antibodies (ANCA) are found in pauci-immune necrotizing crescentic glomerulonephritis. In the past, the role of complement in ANCA-associated vasculitis (AAV) was assumed to be minimal. More recently, however, it was found that blocking the complement cascade in a mouse model of AAV reduces glomerular damage. Immune complex deposits have been found in biopsies from AAV patients. In this study, we questioned whether immune complex formation or deposition may result in complement activation in ANCA-associated glomerulonephritis. Methods ANCA-positive patients from the Limburg Renal Registry were included between 1979 and 2011. Renal histology was documented together with immunoglobulin and complement immunofluorescence. In addition, C3d, properdin, C4d and mannose-binding lectin (MBL) were stained. Electron microscopy was performed. Circulating immune complexes were determined in a subset of patients, as well as C3 allotypes. Results C3c was found in 78 of 187 renal biopsies (41.7%) divided over 32.3% of proteinase-3 (PR3)-AAV patients and 52.3% of myeloperoxidase (MPO)-AAV patients (P = 0.006), whereas C3d was found positive in 51.1% of PR3-AAV patients and 70.4% of MPO-AAV patients (P = 0.105). C4d was found positive in 70.8%, properdin in 38.7% and MBL in 30.4% of patients. Whereas C4d and MBL positivity was similar between the AGN groups, properdin was more common in biopsies classified as crescentic compared with biopsies classified as focal or mixed. Renal biopsies positive for C3d and/or properdin showed more cellular crescents and less normal glomeruli compared with biopsies negative for C3d and/or properdin (P < 0.05). In 3 out of 43 renal biopsies analysed by electron microscopy, small electron dense deposits were found. In 14 of 46 patients analysed, circulating immune complexes were detectable. No association between histological findings and C3 allotypes was found. Conclusions In the majority of AAV patients, no immune complex deposits were found in their renal biopsies. C3d, C4d and C5b-9 staining, however, was found to be positive in a majority of analysed renal biopsies. Importantly, C3d and properdin staining was associated with cellular crescents. We hypothesize that local immune complexes are quickly degraded in AAV and therefore not visible by electron microscopy. Our findings are compatible with the hypothesis that complement activation in AAV occurs predominantly via alternative pathway activation.
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Affiliation(s)
- Marc Hilhorst
- Clinical & Experimental Immunology, Cardiovascular Research Centre Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Pieter van Paassen
- Clinical & Experimental Immunology, Cardiovascular Research Centre Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands.,Department of Nephrology, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands
| | - Henk van Rie
- Clinical & Experimental Immunology, Cardiovascular Research Centre Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands.,Department of Pathology, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands
| | - Nele Bijnens
- Clinical & Experimental Immunology, Cardiovascular Research Centre Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands.,Department of Pathology, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands
| | - Petra Heerings-Rewinkel
- Clinical & Experimental Immunology, Cardiovascular Research Centre Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Peter van Breda Vriesman
- Clinical & Experimental Immunology, Cardiovascular Research Centre Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Jan Willem Cohen Tervaert
- Clinical & Experimental Immunology, Cardiovascular Research Centre Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands
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32
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Łukawska E, Polcyn-Adamczak M, Niemir ZI. The role of the alternative pathway of complement activation in glomerular diseases. Clin Exp Med 2018; 18:297-318. [DOI: 10.1007/s10238-018-0491-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 02/12/2018] [Indexed: 01/20/2023]
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33
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Loeschenberger B, Niess L, Würzner R, Schwelberger H, Eder IE, Puhr M, Guenther J, Troppmair J, Rudnicki M, Neuwirt H. Calcineurin inhibitor-induced complement system activation via ERK1/2 signalling is inhibited by SOCS-3 in human renal tubule cells. Eur J Immunol 2017; 48:330-343. [PMID: 29143318 DOI: 10.1002/eji.201747135] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 09/12/2017] [Accepted: 11/03/2017] [Indexed: 12/22/2022]
Abstract
One factor that significantly contributes to renal allograft loss is chronic calcineurin inhibitor (CNI) nephrotoxicity (CIN). Among other factors, the complement (C-) system has been proposed to be involved CIN development. Hence, we investigated the impact of CNIs on intracellular signalling and the effects on the C-system in human renal tubule cells. In a qPCR array, CNI treatment upregulated C-factors and downregulated SOCS-3 and the complement inhibitors CD46 and CD55. Additionally, ERK1/-2 was required for these regulations. Following knock-down and overexpression of SOCS-3, we found that SOCS-3 inhibits ERK1/-2 signalling. Finally, we assessed terminal complement complex formation, cell viability and apoptosis. Terminal complement complex formation was induced by CNIs. Cell viability was significantly decreased, whereas apoptosis was increased. Both effects were reversed under complement component-depleted conditions. In vivo, increased ERK1/-2 phosphorylation and SOCS-3 downregulation were observed at the time of transplantation in renal allograft patients who developed a progressive decline of renal function in the follow-up compared to stable patients. The progressive cohort also had lower total C3 levels, suggesting higher complement activity at baseline. In conclusion, our data suggest that SOCS-3 inhibits CNI-induced ERK1/-2 signalling, thereby blunting the negative control of C-system activation.
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Affiliation(s)
| | - Lea Niess
- Department of Internal Medicine IV, Innsbruck Medical University, Innsbruck, Austria
| | - Reinhard Würzner
- Division of Hygiene and Medical Microbiology, Innsbruck Medical University, Innsbruck, Austria
| | - Hubert Schwelberger
- Molecular Biology Laboratory, Department of Visceral, Transplant and Thoracic Surgery, Innsbruck Medical University, Innsbruck, Austria
| | - Iris E Eder
- Department of Urology, Division of Experimental Urology, Innsbruck Medical University, Innsbruck, Austria
| | - Martin Puhr
- Department of Urology, Division of Experimental Urology, Innsbruck Medical University, Innsbruck, Austria
| | - Julia Guenther
- Daniel Swarovski Research Laboratory, Department of Visceral, Transplant- and Thoracic Surgery, Innsbruck Medical University, Innsbruck, Austria
| | - Jakob Troppmair
- Daniel Swarovski Research Laboratory, Department of Visceral, Transplant- and Thoracic Surgery, Innsbruck Medical University, Innsbruck, Austria
| | - Michael Rudnicki
- Department of Internal Medicine IV, Innsbruck Medical University, Innsbruck, Austria
| | - Hannes Neuwirt
- Department of Internal Medicine IV, Innsbruck Medical University, Innsbruck, Austria
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34
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Non-Invasive whole-body detection of complement activation using radionuclide imaging in a mouse model of myocardial ischaemia-reperfusion injury. Sci Rep 2017; 7:16090. [PMID: 29170426 PMCID: PMC5700950 DOI: 10.1038/s41598-017-16387-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 11/13/2017] [Indexed: 11/30/2022] Open
Abstract
Complement activation is a recognised mediator of myocardial ischaemia-reperfusion-injury (IRI) and cardiomyocytes are a known source of complement proteins including the central component C3, whose activation products can mediate tissue inflammation, cell death and profibrotic signalling. We investigated the potential to detect and quantify the stable covalently bound product C3d by external body imaging, as a marker of complement activation in heart muscle in a murine model of myocardial IRI. We used single-photon-emission-computed-tomography (SPECT) in conjunction with 99mTechnecium-labelled recombinant complement receptor 2 (99mTc-rCR2), which specifically detects C3d at the site of complement activation. Compared to control imaging with an inactive CR2 mutant (99mTc-K41E CR2) or an irrelevant protein (99mTc-PSMA) or using 99mTc-rCR2 in C3-deficient mice, the use of 99mTc-rCR2 in complement-intact mice gave specific uptake in the reperfused myocardium. The heart to skeletal muscle ratio of 99mTc-rCR2 was significantly higher than in the three control groups. Histological analysis confirmed specific uptake of 99mTc-rCR2. Following therapeutic inhibition of complement C3 activation, we found reduced myocardial uptake of 99mTc-rCR2. We conclude, therefore that 99mTc-rCR2 imaging can be used for non-invasive detection of activated complement and in future could be exploited to quantify the severity of myocardial damage due to complement activation.
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35
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Stapleton CP, Conlon PJ, Phelan PJ. Using omics to explore complications of kidney transplantation. Transpl Int 2017; 31:251-262. [PMID: 28892567 DOI: 10.1111/tri.13067] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 06/26/2017] [Accepted: 09/05/2017] [Indexed: 12/12/2022]
Abstract
The importance of genetic and biochemical variation in renal transplant outcomes has been clear since the discovery of the HLA in the 1950s. Since that time, there have been huge advancements in both transplantation and omics. In recent years, there has seen an increased number of genome-, proteome- and transcriptome-wide studies in the field of transplantation moving away from the earlier candidate gene/protein approaches. These areas have the potential to lead to the development of personalized treatment depending on individual molecular risk profiles. Here, we discuss recent progress and the current literature surrounding omics and renal transplant complications.
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Affiliation(s)
- Caragh P Stapleton
- Department of Molecular and Cellular Therapeutics, The Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Peter J Conlon
- Department of Nephrology, Beaumont Hospital, Dublin, Ireland.,Department of Medicine, The Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Paul J Phelan
- Department of Nephrology, Royal Infirmary of Edinburgh, NHS Lothian, Edinburgh, United Kingdom
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36
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Michielsen LA, van Zuilen AD, Muskens IS, Verhaar MC, Otten HG. Complement Polymorphisms in Kidney Transplantation: Critical in Graft Rejection? Am J Transplant 2017; 17:2000-2007. [PMID: 28097805 DOI: 10.1111/ajt.14199] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 12/21/2016] [Accepted: 01/04/2017] [Indexed: 01/25/2023]
Abstract
The complement system, as part of the innate immune system, plays an important role in renal transplantation. Complement is involved in the protection against foreign organisms and clearance of apoptotic cells but can also cause injury to the renal allograft, for instance, via antibody binding or in ischemia-reperfusion injury. Numerous polymorphisms in complement factors have been identified thus far; some of them result in different functionalities or alter complement levels. In this review, we provide an overview of the literature on the role of complement polymorphisms in renal transplantation. Furthermore, we discuss functional complement polymorphisms that have not yet been investigated in kidney transplantation. By investigating multiple polymorphisms both in donor and recipient at the same time, a complotype can be constructed. Because the combination of multiple polymorphisms is likely to have a greater impact than a single one, this could provide valuable prognostic information.
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Affiliation(s)
- L A Michielsen
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, the Netherlands
| | - A D van Zuilen
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, the Netherlands
| | - I S Muskens
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, the Netherlands
| | - M C Verhaar
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, the Netherlands
| | - H G Otten
- Laboratory of Translational Immunology, University Medical Center Utrecht, Utrecht, the Netherlands
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37
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Jager NM, Poppelaars F, Daha MR, Seelen MA. Complement in renal transplantation: The road to translation. Mol Immunol 2017; 89:22-35. [PMID: 28558950 DOI: 10.1016/j.molimm.2017.05.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 05/17/2017] [Accepted: 05/19/2017] [Indexed: 02/08/2023]
Abstract
Renal transplantation is the treatment of choice for patients with end-stage renal disease. The vital role of the complement system in renal transplantation is widely recognized. This review discusses the role of complement in the different phases of renal transplantation: in the donor, during preservation, in reperfusion and at the time of rejection. Here we examine the current literature to determine the importance of both local and systemic complement production and how complement activation contributes to the pathogenesis of renal transplant injury. In addition, we dissect the complement pathways involved in the different phases of renal transplantation. We also review the therapeutic strategies that have been tested to inhibit complement during the kidney transplantation. Several clinical trials are currently underway to evaluate the therapeutic potential of complement inhibition for the treatment of brain death-induced renal injury, renal ischemia-reperfusion injury and acute rejection. We conclude that it is expected that in the near future, complement-targeted therapeutics will be used clinically in renal transplantation. This will hopefully result in improved renal graft function and increased graft survival.
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Affiliation(s)
- Neeltina M Jager
- Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
| | - Felix Poppelaars
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Mohamed R Daha
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; Department of Nephrology, Leiden University Medical Center, University of Leiden, Leiden, The Netherlands
| | - Marc A Seelen
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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Vanhove T, Goldschmeding R, Kuypers D. Kidney Fibrosis: Origins and Interventions. Transplantation 2017; 101:713-726. [PMID: 27941433 PMCID: PMC7228593 DOI: 10.1097/tp.0000000000001608] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 10/24/2016] [Accepted: 11/10/2016] [Indexed: 02/06/2023]
Abstract
All causes of renal allograft injury, when severe and/or sustained, can result in chronic histological damage of which interstitial fibrosis and tubular atrophy are dominant features. Unless a specific disease process can be identified, what drives interstitial fibrosis and tubular atrophy progression in individual patients is often unclear. In general, clinicopathological factors known to predict and drive allograft fibrosis include graft quality, inflammation (whether "nonspecific" or related to a specific diagnosis), infections, such as polyomavirus-associated nephropathy, calcineurin inhibitors (CNI), and genetic factors. The incidence and severity of chronic histological damage have decreased substantially over the last 3 decades, but it is difficult to disentangle what effects individual innovations (eg, better matching and preservation techniques, lower CNI dosing, BK viremia screening) may have had. There is little evidence that CNI-sparing/minimization strategies, steroid minimization or renin-angiotensin-aldosterone system blockade result in better preservation of intermediate-term histology. Treatment of subclinical rejections has only proven beneficial to histological and functional outcome in studies in which the rate of subclinical rejection in the first 3 months was greater than 10% to 15%. Potential novel antifibrotic strategies include antagonists of transforming growth factor-β, connective tissue growth factor, several tyrosine kinase ligands (epidermal growth factor, platelet-derived growth factor, vascular endothelial growth factor), endothelin and inhibitors of chemotaxis. Although many of these drugs are mainly being developed and marketed for oncological indications and diseases, such as idiopathic pulmonary fibrosis, a number may hold promise in the treatment of diabetic nephropathy, which could eventually lead to applications in renal transplantation.
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Affiliation(s)
- Thomas Vanhove
- 1 Department of Microbiology and Immunology, KU Leuven-University of Leuven, Leuven, Belgium. 2 Department of Nephrology and Renal Transplantation, University Hospitals Leuven, Leuven, Belgium. 3 Department of Pathology, University Medical Center Utrecht, Utrecht, the Netherlands
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Poppelaars F, Seelen MA. Complement-mediated inflammation and injury in brain dead organ donors. Mol Immunol 2016; 84:77-83. [PMID: 27989433 DOI: 10.1016/j.molimm.2016.11.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 11/08/2016] [Accepted: 11/08/2016] [Indexed: 01/16/2023]
Abstract
The importance of the complement system in renal ischemia-reperfusion injury and acute rejection is widely recognized, however its contribution to the pathogenesis of tissue damage in the donor remains underexposed. Brain-dead (BD) organ donors are still the primary source of organs for transplantation. Brain death is characterized by hemodynamic changes, hormonal dysregulation, and immunological activation. Recently, the complement system has been shown to be involved. In BD organ donors, complement is activated systemically and locally and is an important mediator of inflammation and graft injury. Furthermore, complement activation can be used as a clinical marker for the prediction of graft function after transplantation. Experimental models of BD have shown that inhibition of the complement cascade is a successful method to reduce inflammation and injury of donor grafts, thereby improving graft function and survival after transplantation. Consequently, complement-targeted therapeutics in BD organ donors form a new opportunity to improve organ quality for transplantation. Future studies should further elucidate the mechanism responsible for complement activation in BD organ donors.
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Affiliation(s)
- Felix Poppelaars
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands
| | - Marc A Seelen
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groningen, 9700 RB Groningen, The Netherlands.
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40
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Abstract
The complement system is reemerging in the last few years not only as key element of innate immunity against pathogens, but also as a main regulator of local adaptive responses, affecting dendritic cells as well as T and B lymphocytes. We review data showing that leucocytes are capable of significant autocrine synthesis of complement proteins, and express a large range of complement receptors, which in turn regulate their differentiation and effector functions while cross talking with other innate receptors such as Toll-like receptors. Other unconventional roles of complement proteins are reviewed, including their impact in non-leukocytes and their intracellular cleavage by vesicular proteases, which generate critical cues required for T cell function. Thus, leucocytes are very much aware of complement-derived information, both extracellular and intracellular, to elaborate their responses, offering rich avenues for therapeutic intervention and new hypothesis for conserved major histocompatibility complex complotypes.
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41
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Valero-Hervás DM, Sánchez-Zapardiel E, Castro MJ, Gallego-Bustos F, Cambra F, Justo I, Laguna-Goya R, Jiménez-Romero C, Moreno E, López-Medrano F, San Juan R, Fernández-Ruiz M, Aguado JM, Paz-Artal E. Complement C3F allotype synthesized by liver recipient modifies transplantation outcome independently from donor hepatic C3. Clin Transplant 2016; 31. [PMID: 27801525 DOI: 10.1111/ctr.12866] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/26/2016] [Indexed: 12/12/2022]
Abstract
Complement component 3 (C3) presents both slow (C3S) and fast (C3F) variants, which can be locally produced and activated by immune system cells. We studied C3 recipient variants in 483 liver transplant patients by RT-PCR-HRM to determine their effect on graft outcome during the first year post-transplantation. Allograft survival was significantly decreased in C3FF recipients (C3SS 95% vs C3FS 91% vs C3FF 83%; P=.01) or C3F allele carriers (C3F absence 95% vs C3F presence 90%, P=.02). C3FF genotype or presence of C3F allele independently increased risk for allograft loss (OR: 2.38, P=.005 and OR: 2.66, P=.02, respectively). C3FF genotype was more frequent among patients whose first infection was of viral etiology (C3SS 13% vs C3FS 18% vs C3FF 32%; P=.04) and independently increased risk for post-transplant viral infections (OR: 3.60, P=.008). On the other hand, C3FF and C3F protected from rejection events (OR: 0.54, P=.03 and OR: 0.63, P=.047, respectively). Differences were not observed in hepatitis C virus recurrence or patient survival. In conclusion, we show that, independently from C3 variants produced by donor liver, C3F variant from recipient diminishes allograft survival, increases susceptibility to viral infections, and protects from rejection after transplantation. C3 genotyping of liver recipients may be useful to stratify risk.
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Affiliation(s)
| | | | - María José Castro
- Department of Immunology, Hospital 12 de Octubre, Madrid, Spain.,I+12 Research Institute, Hospital 12 de Octubre, Madrid, Spain
| | | | - Félix Cambra
- Department of General and Digestive Surgery and Abdominal Organ Transplantation, Hospital 12 de Octubre, Madrid, Spain
| | - Iago Justo
- Department of General and Digestive Surgery and Abdominal Organ Transplantation, Hospital 12 de Octubre, Madrid, Spain
| | - Rocío Laguna-Goya
- Department of Immunology, Hospital 12 de Octubre, Madrid, Spain.,I+12 Research Institute, Hospital 12 de Octubre, Madrid, Spain
| | - Carlos Jiménez-Romero
- I+12 Research Institute, Hospital 12 de Octubre, Madrid, Spain.,Department of General and Digestive Surgery and Abdominal Organ Transplantation, Hospital 12 de Octubre, Madrid, Spain.,School of Medicine, Universidad Complutense de Madrid, Madrid, Spain
| | - Enrique Moreno
- I+12 Research Institute, Hospital 12 de Octubre, Madrid, Spain.,Department of General and Digestive Surgery and Abdominal Organ Transplantation, Hospital 12 de Octubre, Madrid, Spain.,School of Medicine, Universidad Complutense de Madrid, Madrid, Spain
| | - Francisco López-Medrano
- I+12 Research Institute, Hospital 12 de Octubre, Madrid, Spain.,Unit of Infectious Diseases, Hospital 12 de Octubre, Madrid, Spain
| | - Rafael San Juan
- I+12 Research Institute, Hospital 12 de Octubre, Madrid, Spain.,Unit of Infectious Diseases, Hospital 12 de Octubre, Madrid, Spain
| | - Mario Fernández-Ruiz
- I+12 Research Institute, Hospital 12 de Octubre, Madrid, Spain.,Unit of Infectious Diseases, Hospital 12 de Octubre, Madrid, Spain
| | - José María Aguado
- I+12 Research Institute, Hospital 12 de Octubre, Madrid, Spain.,School of Medicine, Universidad Complutense de Madrid, Madrid, Spain.,Unit of Infectious Diseases, Hospital 12 de Octubre, Madrid, Spain
| | - Estela Paz-Artal
- Department of Immunology, Hospital 12 de Octubre, Madrid, Spain.,I+12 Research Institute, Hospital 12 de Octubre, Madrid, Spain.,School of Medicine, Universidad Complutense de Madrid, Madrid, Spain.,Section of Immunology, Universidad San Pablo CEU, Madrid, Spain
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Poppelaars F, Damman J, de Vrij EL, Burgerhof JGM, Saye J, Daha MR, Leuvenink HG, Uknis ME, Seelen MAJ. New insight into the effects of heparinoids on complement inhibition by C1-inhibitor. Clin Exp Immunol 2016; 184:378-88. [PMID: 26874675 DOI: 10.1111/cei.12777] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2016] [Indexed: 01/22/2023] Open
Abstract
Complement activation is of major importance in numerous pathological conditions. Therefore, targeted complement inhibition is a promising therapeutic strategy. C1-esterase inhibitor (C1-INH) controls activation of the classical pathway (CP) and the lectin pathway (LP). However, conflicting data exist on inhibition of the alternative pathway (AP) by C1-INH. The inhibitory capacity of C1-INH for the CP is potentiated by heparin and other glycosaminoglycans, but no data exist for the LP and AP. The current study investigates the effects of C1-INH in the presence or absence of different clinically used heparinoids on the CP, LP and AP. Furthermore, the combined effects of heparinoids and C1-INH on coagulation were investigated. C1-INH, heparinoids or combinations were analysed in a dose-dependent fashion in the presence of pooled serum. Functional complement activities were measured simultaneously using the Wielisa(®) -kit. The activated partial thrombin time was determined using an automated coagulation analyser. The results showed that all three complement pathways were inhibited significantly by C1-INH or heparinoids. Next to their individual effects on complement activation, heparinoids also enhanced the inhibitory capacity of C1-INH significantly on the CP and LP. For the AP, significant potentiation of C1-INH by heparinoids was found; however, this was restricted to certain concentration ranges. At low concentrations the effect on blood coagulation by combining heparinoids with C1-INH was minimal. In conclusion, our study shows significant potentiating effects of heparinoids on the inhibition of all complement pathways by C1-INH. Therefore, their combined use is a promising and a potentially cost-effective treatment option for complement-mediated diseases.
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Affiliation(s)
- F Poppelaars
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groninge, Groningen
| | - J Damman
- Department of Pathology, University of Amsterdam, Academic Medical Centre, Amsterdam
| | - E L de Vrij
- Department of Clinical Pharmacy and Pharmacology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - J G M Burgerhof
- Department of Epidemiology, University of Groningen, University Medical Centre Groningen, Groningen, the Netherlands
| | - J Saye
- ViroPharma, Inc., Exton, PA, USA
| | - M R Daha
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groninge, Groningen.,Department of Nephrology, University of Leiden, Leiden University Medical Center, Leiden
| | - H G Leuvenink
- Department of Surgery, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | | | - M A J Seelen
- Department of Internal Medicine, Division of Nephrology, University of Groningen, University Medical Center Groninge, Groningen
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43
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Stojanova J, Pouché L, Picard N. Genetic polymorphisms in the immune response: A focus on kidney transplantation. Clin Biochem 2016; 49:363-76. [DOI: 10.1016/j.clinbiochem.2015.07.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 07/04/2015] [Accepted: 07/08/2015] [Indexed: 02/06/2023]
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Xiao F, Ma L, Zhao M, Smith RA, Huang G, Jones PM, Persaud S, Pingitore A, Dorling A, Lechler R, Lombardi G. APT070 (mirococept), a membrane-localizing C3 convertase inhibitor, attenuates early human islet allograft damage in vitro and in vivo in a humanized mouse model. Br J Pharmacol 2016; 173:575-87. [PMID: 26565566 PMCID: PMC4728428 DOI: 10.1111/bph.13388] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 10/03/2015] [Accepted: 11/03/2015] [Indexed: 12/11/2022] Open
Abstract
Background and Purpose A major obstacle to islet cell transplantation is the early loss of transplanted islets resulting from the instant blood‐mediated inflammation reaction (IBMIR). The activation of complement pathways plays a central role in IBMIR. The aim of this study was to test the inhibitory effect of “painting” human islets with APT070, a membrane‐localizing C3 convertase inhibitor, on inflammation evoked by exposure to human serum in vitro and by transplantation in vivo in a humanized diabetic mouse model. Experimental Approach In vitro, human islets pre‐incubated with APT070 were exposed to allogeneic whole blood. In vivo, similarly treated islets were transplanted underneath the kidney capsule of streptozotocin‐induced diabetic NOD‐SCID IL2rγ−/− mice that had been reconstituted with human CD34+ stem cells. Complement activation and islet hormone content were assayed using enzyme‐linked immunosorbent assays. Supernatants and sera were assayed for cytokines using cytometric beads array. Morphology of the islets incubated with human serum in vitro and in graft‐bearing kidney were evaluated using immunofluorescence staining. Key Results Pre‐incubation with APT070 decreased C‐peptide release and iC3b production in vitro, with diminished deposition of C4d and C5b‐9 in islets embedded in blood clots. In vivo, the APT070‐treated islets maintained intact structure and showed less infiltration of inflammatory cells than untreated islets. The pretreatments also significantly reduced pro‐inflammatory cytokines in supernatants and sera. Conclusions and Implications Pre‐treatment of islets with APT070 could reduce intra‐islet inflammation with accompanying preservation of insulin secretion by beta cells. APT070 could be as a potential therapeutic tool in islet transplantation.
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Affiliation(s)
- Fang Xiao
- Division of Transplantation Immunology and Mucosal Biology, MRC Centre for Transplantation, King's College London, 5th Floor Tower Wing, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
| | - Liang Ma
- Division of Transplantation Immunology and Mucosal Biology, MRC Centre for Transplantation, King's College London, 5th Floor Tower Wing, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
| | - Min Zhao
- Department of Diabetes & Endocrinology, King's College London, 2nd Floor, The Rayne Institute, 123 Coldharbour Lane, London, SE5 9NU, UK
| | - Richard A Smith
- Division of Transplantation Immunology and Mucosal Biology, MRC Centre for Transplantation, King's College London, 5th Floor Tower Wing, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
| | - Guocai Huang
- Department of Diabetes & Endocrinology, King's College London, 2nd Floor, The Rayne Institute, 123 Coldharbour Lane, London, SE5 9NU, UK
| | - Peter M Jones
- Division of Diabetes & Nutritional Sciences, School of Medicine, King's College London, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
| | - Shanta Persaud
- Division of Diabetes & Nutritional Sciences, School of Medicine, King's College London, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
| | - Attilio Pingitore
- Division of Diabetes & Nutritional Sciences, School of Medicine, King's College London, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
| | - Anthony Dorling
- Division of Transplantation Immunology and Mucosal Biology, MRC Centre for Transplantation, King's College London, 5th Floor Tower Wing, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
| | - Robert Lechler
- Division of Transplantation Immunology and Mucosal Biology, MRC Centre for Transplantation, King's College London, 5th Floor Tower Wing, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
| | - Giovanna Lombardi
- Division of Transplantation Immunology and Mucosal Biology, MRC Centre for Transplantation, King's College London, 5th Floor Tower Wing, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
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45
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Simmonds MJ. Using Genetic Variation to Predict and Extend Long-term Kidney Transplant Function. Transplantation 2016; 99:2038-48. [PMID: 26262502 DOI: 10.1097/tp.0000000000000836] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Renal transplantation has transformed the life of patients with end-stage renal disease and other chronic kidney disorders by returning endogenous kidney function and enabling patients to cease dialysis. Several clinical indicators of graft outcome and long-term function have been established. Although rising creatinine levels and graft biopsy can be used to determine graft loss, identifying early predictors of graft function will not only improve our ability to predict long-term graft outcome but importantly provide a window of opportunity to therapeutically intervene to preserve graft function before graft failure has occurred. Since understanding the importance of matching genetic variation at the HLA region between donors and recipients and translating this into clinical practise to improve transplant outcome, much focus has been placed on trying to identify additional genetic predictors of transplant outcome/function. This review will focus on how candidate gene studies have identified variants within immunosuppression, immune response, fibrotic pathways, and specific ethnic groups, which correlate with graft outcome. We will also discuss the challenges faced by candidate gene studies, such as differences in donor and recipient selection criteria and use of small data sets, which have led to many genes failing to be consistently associated with transplant outcome. This review will also look at how recent advances in our understanding of and ability to screen the genome are starting to provide new insights into the mechanisms behind long-term graft loss and with it the opportunity to target these pathways therapeutically to ultimately increase graft lifespan and the associated benefits to patients.
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Affiliation(s)
- Matthew J Simmonds
- 1 Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, Churchill Hospital, Headington, Oxford, United Kingdom
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46
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Ermini L, Weale ME, Brown KM, Mesa IR, Howell WM, Vaughan R, Chowdhury P, Sacks SH, Sheerin NS. Systematic assessment of the influence of complement gene polymorphisms on kidney transplant outcome. Immunobiology 2015; 221:528-34. [PMID: 26797657 DOI: 10.1016/j.imbio.2015.12.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 12/10/2015] [Indexed: 01/01/2023]
Abstract
The importance of the innate immune system, including complement, in causing transplant injury and augmenting adaptive immune responses is increasingly recognized. Therefore variability in graft outcome may in part be due to genetic polymorphism in genes encoding proteins of the immune system. This study assessed the relationship between single nucleotide polymorphisms (SNPs) in complement genes and outcome after transplantation. Analysis was performed on two patient cohorts of 650 and 520 transplant recipients. 505 tagged SNPs in 47 genes were typed in both donor and recipient. The relationships between SNPs and graft survival, serum creatinine, delayed graft function and acute rejection were analyzed. One recipient SNP in the gene encoding mannose binding lectin was associated with graft outcome after correction for analysis of multiple SNPs (p=6.41 × 10(-5)). When further correction was applied to account for analysis of the effect of SNPs in both donor and recipient this lost significance. Despite association p values of <0.001 no SNP was significantly associated with clinical phenotypes after Bonferroni correction. In conclusion, the variability seen in transplant outcome in this patient cohort cannot be explained by variation in complement genes. If causal genetic effects exist in these genes, they are too small to be detected by this study.
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Affiliation(s)
- Luca Ermini
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
| | - Michael E Weale
- Department of Medical and Molecular Genetics, King's College, London SE1 9RT, UK.
| | | | - Irene Rebollo Mesa
- Department of Medical and Molecular Genetics, King's College, London SE1 9RT, UK.
| | | | - Robert Vaughan
- Clinical Transplantation Laboratory, GSTS Pathology, Guy's Hospital, London SE1 9RT, UK.
| | | | - Steven H Sacks
- MRC Centre for Transplantation, King's College, London SE1 9RT, UK.
| | - Neil S Sheerin
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne NE2 4HH, UK.
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47
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Abstract
PURPOSE OF REVIEW To summarize the current knowledge regarding mechanisms linking the complement system to transplant injury, highlighting findings reported since 2013. RECENT FINDINGS Building upon the documentation that complement activation is a pathogenic mediator of posttransplant ischemia-reperfusion injury, emerging evidence from animal models indicates that blocking either the classical or lectin pathways attenuates ischemia-reperfusion injury. Immune cell-derived and locally activated complement, including intracellular C3, positively modulates alloreactive T-cell activation and expansion, whereby simultaneously inhibiting regulatory T-cell induction and function, and together promoting transplant rejection. Although alloantibody-initiated complement activation directly injures target cells, complement-dependent signals activate endothelial cells to facilitate T-cell-dependent inflammation. Complement activation within allografts contributes to progressive chronic injury and fibrosis. SUMMARY The complement cascade, traditionally considered to be relevant to transplantation only as an effector mechanism of antibody-initiated allograft injury, is now understood to damage the allograft through multiple mechanisms. Complement activation promotes posttransplant ischemia-reperfusion injury, formation and function of alloantibody, differentiation and function of alloreactive T cells, and contributes to chronic progressive allograft failure. The recognition that complement affects transplant injury at many levels provides a foundation for targeting complement as a therapy to prolong transplant survival and improve patient health.
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48
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Sharif‐Paghaleh E, Yap ML, Meader LL, Chuamsaamarkkee K, Kampmeier F, Badar A, Smith RA, Sacks S, Mullen GE. Noninvasive Imaging of Activated Complement in Ischemia-Reperfusion Injury Post-Cardiac Transplant. Am J Transplant 2015; 15:2483-90. [PMID: 25906673 PMCID: PMC4654255 DOI: 10.1111/ajt.13299] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 02/24/2015] [Accepted: 02/28/2015] [Indexed: 01/25/2023]
Abstract
Ischemia-reperfusion injury (IRI) is inevitable in solid organ transplantation, due to the transplanted organ being ischemic for prolonged periods prior to transplantation followed by reperfusion. The complement molecule C3 is present in the circulation and is also synthesized by tissue parenchyma in early response to IRI and the final stable fragment of activated C3, C3d, can be detected on injured tissue for several days post-IRI. Complement activation post-IRI was monitored noninvasively by single photon emission computed tomography (SPECT) and CT using (99m) Tc-recombinant complement receptor 2 ((99m) Tc-rCR2) in murine models of cardiac transplantation following the induction of IRI and compared to (99m) Tc-rCR2 in C3(-/-) mice or with the irrelevant protein (99m) Tc-prostate-specific membrane antigen antibody fragment (PSMA). Significant uptake with (99m) Tc-rCR2 was observed as compared to C3(-/-) or (99m) Tc-PSMA. In addition, the transplanted heart to muscle ratio of (99m) Tc-rCR2 was significantly higher than (99m) Tc-PSMA or C3(-/-) . The results were confirmed by histology and autoradiography. (99m) Tc-rCR2 can be used for noninvasive detection of activated complement and in future may be used to quantify the severity of transplant damage due to complement activation postreperfusion.
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Affiliation(s)
- E. Sharif‐Paghaleh
- Division of Imaging and Biomedical EngineeringSchool of MedicineKing's College LondonLondonEngland,MRC Centre for TransplantationKing's College LondonLondonEngland,Department of ImmunologyFaculty of MedicineTehran University of Medical SciencesTehranIran
| | - M. L. Yap
- Division of Imaging and Biomedical EngineeringSchool of MedicineKing's College LondonLondonEngland
| | - L. L. Meader
- MRC Centre for TransplantationKing's College LondonLondonEngland
| | - K. Chuamsaamarkkee
- Division of Imaging and Biomedical EngineeringSchool of MedicineKing's College LondonLondonEngland
| | - F. Kampmeier
- Division of Imaging and Biomedical EngineeringSchool of MedicineKing's College LondonLondonEngland
| | - A. Badar
- Division of Imaging and Biomedical EngineeringSchool of MedicineKing's College LondonLondonEngland
| | - R. A. Smith
- MRC Centre for TransplantationKing's College LondonLondonEngland
| | - S. Sacks
- MRC Centre for TransplantationKing's College LondonLondonEngland
| | - G. E. Mullen
- Division of Imaging and Biomedical EngineeringSchool of MedicineKing's College LondonLondonEngland,MRC Centre for TransplantationKing's College LondonLondonEngland
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49
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Sfyroera G, Ricklin D, Reis ES, Chen H, Wu EL, Kaznessis YN, Ekdahl KN, Nilsson B, Lambris JD. Rare loss-of-function mutation in complement component C3 provides insight into molecular and pathophysiological determinants of complement activity. THE JOURNAL OF IMMUNOLOGY 2015; 194:3305-16. [PMID: 25712219 DOI: 10.4049/jimmunol.1402781] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The plasma protein C3 is a central element in the activation and effector functions of the complement system. A hereditary dysfunction of C3 that prevents complement activation via the alternative pathway (AP) was described previously in a Swedish family, but its genetic cause and molecular consequences have remained elusive. In this study, we provide these missing links by pinpointing the dysfunction to a point mutation in the β-chain of C3 (c.1180T > C; p.Met(373)Thr). In the patient's plasma, AP activity was completely abolished and could only be reconstituted with the addition of normal C3. The M373T mutation was localized to the macroglobulin domain 4 of C3, which contains a binding site for the complement inhibitor compstatin and is considered critical for the interaction of C3 with the AP C3 convertase. Structural analyses suggested that the mutation disturbs the integrity of macroglobulin domain 4 and induces conformational changes that propagate into adjacent regions. Indeed, C3 M373T showed an altered binding pattern for compstatin and surface-bound C3b, and the presence of Thr(373) in either the C3 substrate or convertase-affiliated C3b impaired C3 activation and opsonization. In contrast to known gain-of-function mutations in C3, patients affected by this loss-of-function mutation did not develop familial disease, but rather showed diverse and mostly episodic symptoms. Our study therefore reveals the molecular mechanism of a relevant loss-of-function mutation in C3 and provides insight into the function of the C3 convertase, the differential involvement of C3 activity in clinical conditions, and some potential implications of therapeutic complement inhibition.
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Affiliation(s)
- Georgia Sfyroera
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Daniel Ricklin
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Edimara S Reis
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Hui Chen
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Emilia L Wu
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455
| | - Yiannis N Kaznessis
- Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN 55455
| | - Kristina N Ekdahl
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory, Uppsala University, SE-751 85 Uppsala, Sweden; and Linnæus Center of Biomaterials Chemistry, Linnæus University, SE-391 82 Kalmar, Sweden
| | - Bo Nilsson
- Linnæus Center of Biomaterials Chemistry, Linnæus University, SE-391 82 Kalmar, Sweden
| | - John D Lambris
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104;
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Fearn A, Sheerin NS. Complement activation in progressive renal disease. World J Nephrol 2015; 4:31-40. [PMID: 25664245 PMCID: PMC4317626 DOI: 10.5527/wjn.v4.i1.31] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Revised: 11/14/2014] [Accepted: 12/10/2014] [Indexed: 02/06/2023] Open
Abstract
Chronic kidney disease (CKD) is common and the cause of significant morbidity and mortality. The replacement of functioning nephrons by fibrosis is characteristic of progressive disease. The pathways that lead to fibrosis are not fully understood, although chronic non-resolving inflammation in the kidney is likely to drive the fibrotic response that occurs. In patients with progressive CKD there is histological evidence of inflammation in the interstitium and strategies that reduce inflammation reduce renal injury in pre-clinical models of CKD. The complement system is an integral part of the innate immune system but also augments adaptive immune responses. Complement activation is known to occur in many diverse renal diseases, including glomerulonephritis, thrombotic microangiopathies and transplant rejection. In this review we discuss current evidence that complement activation contributes to progression of CKD, how complement could cause renal inflammation and whether complement inhibition would slow progression of renal disease.
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