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Garrigues RJ, Garrison MP, Garcia BL. The Crystal Structure of the Michaelis-Menten Complex of C1 Esterase Inhibitor and C1s Reveals Novel Insights into Complement Regulation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2024; 213:718-729. [PMID: 38995166 PMCID: PMC11333171 DOI: 10.4049/jimmunol.2400194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 06/13/2024] [Indexed: 07/13/2024]
Abstract
The ancient arm of innate immunity known as the complement system is a blood proteolytic cascade involving dozens of membrane-bound and solution-phase components. Although many of these components serve as regulatory molecules to facilitate controlled activation of the cascade, C1 esterase inhibitor (C1-INH) is the sole canonical complement regulator belonging to a superfamily of covalent inhibitors known as serine protease inhibitors (SERPINs). In addition to its namesake role in complement regulation, C1-INH also regulates proteases of the coagulation, fibrinolysis, and contact pathways. Despite this, the structural basis for C1-INH recognition of its target proteases has remained elusive. In this study, we present the crystal structure of the Michaelis-Menten (M-M) complex of the catalytic domain of complement component C1s and the SERPIN domain of C1-INH at a limiting resolution of 3.94 Å. Analysis of the structure revealed that nearly half of the protein/protein interface is formed by residues outside of the C1-INH reactive center loop. The contribution of these residues to the affinity of the M-M complex was validated by site-directed mutagenesis using surface plasmon resonance. Parallel analysis confirmed that C1-INH-interfacing residues on C1s surface loops distal from the active site also drive affinity of the M-M complex. Detailed structural comparisons revealed differences in substrate recognition by C1s compared with C1-INH recognition and highlight the importance of exosite interactions across broader SERPIN/protease systems. Collectively, this study improves our understanding of how C1-INH regulates the classical pathway of complement, and it sheds new light on how SERPINs recognize their cognate protease targets.
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Affiliation(s)
- Ryan J Garrigues
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Matthew P Garrison
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC
| | - Brandon L Garcia
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC
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Cole MA, Ranjan N, Gerber GF, Pan XZ, Flores-Guerrero D, Chaturvedi S, Sperati CJ, McCrae KR, Brodsky RA. Complement Biosensors Identify a Classical Pathway Stimulus in Complement-Mediated Hemolytic Uremic Syndrome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.29.596475. [PMID: 38854038 PMCID: PMC11160691 DOI: 10.1101/2024.05.29.596475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Complement-mediated hemolytic uremic syndrome (CM-HUS) is a thrombotic microangiopathy characterized by germline variants or acquired antibodies to complement proteins and regulators. Building upon our prior experience with the modified Ham (mHam) assay for ex vivo diagnosis of complementopathies, we have developed an array of cell-based complement "biosensors'' by selective removal of complement regulatory proteins (CD55 and CD59, CD46, or a combination thereof) in an autonomously bioluminescent HEK293 cell line. These biosensors can be used as a sensitive method for diagnosing CM-HUS and monitoring therapeutic complement blockade. Using specific complement pathway inhibitors, this model identifies IgM-driven classical pathway stimulus during both acute disease and in many patients during clinical remission. This provides a potential explanation for ~50% of CM-HUS patients who lack an alternative pathway "driving" variant and suggests at least a subset of CM-HUS is characterized by a breakdown of IgM immunologic tolerance. Key Points CM-HUS has a CP stimulus driven by polyreactive IgM, addressing the mystery of why 40% of CM-HUS lack complement specific variantsComplement biosensors and the bioluminescent mHam can be used to aid in diagnosis of CM-HUS and monitor complement inhibitor therapy.
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Vo A, Ammerman N, Jordan SC. Advances in desensitization for human leukocyte antigen incompatible kidney transplantation. Curr Opin Organ Transplant 2024; 29:104-120. [PMID: 38088373 DOI: 10.1097/mot.0000000000001131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
PURPOSE OF REVIEW Human leukocyte antigen (HLA) sensitization is a major barrier to kidney transplantation induced by exposure to alloantigens through pregnancy, blood product exposure and previous transplantations. Desensitization strategies are undertaken to improve the chances of finding compatible organ offers. Standard approaches to desensitization include the use of plasmapheresis/low dose intravenous immunoglobulin (IVIG) or high dose IVIG plus anti-CD20. However, current methods to reduce HLA antibodies are not always successful, especially in those with calculated panel reactive antibody 99-100%. RECENT FINDINGS Newer desensitization strategies such as imlifidase [immunoglobulin G (IgG) endopeptidase] rapidly inactivates IgG molecules and creates an "antibody-free zone", representing an important advancement in desensitization. However, pathogenic antibodies rebound, increasing allograft injury that is not addressed by imlifidase. Here, use of anti-IL-6R (tocilizumab) or anti-interleukin-6 (clazakizumab) could offer long-term control of B-memory and plasma cell DSA responses to limit graft injury. Agents aimed at long-lived plasma cells (anti-CD38 and anti-BCMAxCD3) could reduce or eliminate HLA-producing plasma cells from marrow niches. Other agents such as complement inhibitors and novel agents inhibiting the Fc neonatal receptor (FcRn) mediated IgG recycling will likely find important roles in desensitization. SUMMARY Use of these agents alone or in combination will likely improve the efficacy and durability of desensitization therapies, improving access to kidney transplantation for immunologically disadvantaged patients.
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Affiliation(s)
- Ashley Vo
- Comprehensive Transplant Center, Cedars Sinai Medical Center, Los Angeles, California, USA
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Praska CE, Tamburrini R, Danobeitia JS. Innate immune modulation in transplantation: mechanisms, challenges, and opportunities. FRONTIERS IN TRANSPLANTATION 2023; 2:1277669. [PMID: 38993914 PMCID: PMC11235239 DOI: 10.3389/frtra.2023.1277669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 11/23/2023] [Indexed: 07/13/2024]
Abstract
Organ transplantation is characterized by a sequence of steps that involve operative trauma, organ preservation, and ischemia-reperfusion injury in the transplant recipient. During this process, the release of damage-associated molecular patterns (DAMPs) promotes the activation of innate immune cells via engagement of the toll-like receptor (TLR) system, the complement system, and coagulation cascade. Different classes of effector responses are then carried out by specialized populations of macrophages, dendritic cells, and T and B lymphocytes; these play a central role in the orchestration and regulation of the inflammatory response and modulation of the ensuing adaptive immune response to transplant allografts. Organ function and rejection of human allografts have traditionally been studied through the lens of adaptive immunity; however, an increasing body of work has provided a more comprehensive picture of the pivotal role of innate regulation of adaptive immune responses in transplant and the potential therapeutic implications. Herein we review literature that examines the repercussions of inflammatory injury to transplantable organs. We highlight novel concepts in the pathophysiology and mechanisms involved in innate control of adaptive immunity and rejection. Furthermore, we discuss existing evidence on novel therapies aimed at innate immunomodulation and how this could be harnessed in the transplant setting.
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Affiliation(s)
- Corinne E. Praska
- Division of Transplantation, Department of Surgery, University of Wisconsin, Madison, WI, United States
| | - Riccardo Tamburrini
- Division of Transplantation, Department of Surgery, University of Wisconsin, Madison, WI, United States
| | - Juan Sebastian Danobeitia
- Division of Transplantation, Department of Surgery, University of Wisconsin, Madison, WI, United States
- Baylor Annette C. and Harold C. Simmons Transplant Institute, Baylor University Medical Center, Dallas, TX, United States
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Zhang J, Yu X, Xie Z, Wang R, Li H, Tang Z, Na N. A bibliometric and knowledge-map analysis of antibody-mediated rejection in kidney transplantation. Ren Fail 2023; 45:2257804. [PMID: 37724568 PMCID: PMC10512841 DOI: 10.1080/0886022x.2023.2257804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 09/06/2023] [Indexed: 09/21/2023] Open
Abstract
OBJECTIVES Antibody-mediated rejection (AMR) is a large obstacle to the long-term survival of allograft kidneys. It is urgent to find novel strategies for its prevention and treatment. Bibliometric analysis is helpful in understanding the directions of one field. Hence, this study aims to analyze the state and emerging trends of AMR in kidney transplantation. METHODS Literature on AMR in kidney transplantation from 1999 to 2022 was collected from the Web of Science Core Collection. HistCite (version 12.03.17), CiteSpace (version 6.2.R2), Bibliometrix 4.1.0 Package from R language, and Gephi (https://gephi.org) were applied to the bibliometric analysis of the annual publications, leading countries/regions, core journals, references, keywords, and trend topics. RESULTS A total of 2522 articles related to AMR in kidney transplantation were included in the analysis and the annual publications increased year by year. There were 10874 authors from 118 institutions located in 70 countries/regions contributing to AMR studies, and the United States took the leading position in both articles and citation scores. Halloran PF from Canada made the most contribution to AMR in kidney transplantation. The top 3 productive journals, American Journal of Transplantation, Transplantation, and Transplantation Proceedings, were associated with transplantation. Moreover, the recent trend topics mainly focused on transplant outcomes, survival, and clinical research. CONCLUSIONS North American and European countries/regions played central roles in AMR of kidney transplantation. Importantly, the prognosis of AMR is the hotspot in the future. Noninvasive strategies like plasma and urine dd-cfDNA may be the most potential direction in the AMR field.
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Affiliation(s)
- Jinhua Zhang
- Department of kidney transplantation, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Xiaowen Yu
- Department of General Surgery, Kunming Municipal Hospital of Traditional Chinese Medicine, the Third Affiliated Hospital of Yunnan University of Chinese Medicine, Kunming, China
| | - Zhenwei Xie
- Department of kidney transplantation, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Ruojiao Wang
- Department of kidney transplantation, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Heng Li
- Department of kidney transplantation, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - ZuoFu Tang
- Department of kidney transplantation, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Ning Na
- Department of kidney transplantation, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
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Trambas IA, Coughlan MT, Tan SM. Therapeutic Potential of Targeting Complement C5a Receptors in Diabetic Kidney Disease. Int J Mol Sci 2023; 24:ijms24108758. [PMID: 37240105 DOI: 10.3390/ijms24108758] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/26/2023] [Accepted: 04/28/2023] [Indexed: 05/28/2023] Open
Abstract
Diabetic kidney disease (DKD) affects 30-40% of patients with diabetes and is currently the leading cause of end-stage renal disease (ESRD). The activation of the complement cascade, a highly conserved element of the innate immune system, has been implicated in the pathogenesis of diabetes and its complications. The potent anaphylatoxin C5a is a critical effector of complement-mediated inflammation. Excessive activation of the C5a-signalling axis promotes a potent inflammatory environment and is associated with mitochondrial dysfunction, inflammasome activation, and the production of reactive oxygen species. Conventional renoprotective agents used in the treatment of diabetes do not target the complement system. Mounting preclinical evidence indicates that inhibition of the complement system may prove protective in DKD by reducing inflammation and fibrosis. Targeting the C5a-receptor signaling axis is of particular interest, as inhibition at this level attenuates inflammation while preserving the critical immunological defense functions of the complement system. In this review, the important role of the C5a/C5a-receptor axis in the pathogenesis of diabetes and kidney injuries will be discussed, and an overview of the status and mechanisms of action of current complement therapeutics in development will be provided.
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Affiliation(s)
- Inez A Trambas
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Melinda T Coughlan
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
| | - Sih Min Tan
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, VIC 3004, Australia
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Sethi S, Jordan SC. Novel therapies for treatment of antibody-mediated rejection of the kidney. Curr Opin Organ Transplant 2023; 28:29-35. [PMID: 36579683 DOI: 10.1097/mot.0000000000001037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
PURPOSE OF REVIEW We aim to discuss current literature on novel therapies for antibody-mediated rejection (AMR) in kidney transplantation with a focus on chronic AMR. RECENT FINDINGS IL-6/IL-6 receptor blockers appear promising in the treatment of chronic AMR. Blocking this pathway was shown to reduce human leucocyte antigen-antibodies, improve histologic inflammation and increase T-regulatory cells. Based on experience in desensitization, IgG degrading endopeptidase, imlifidase, could be effective in AMR. There have been case reports describing the successful use of plasma cell/natural killer-cell-directed anti-CD38 antibody in the treatment of AMR. Off-target effects have been noted and strategies to mitigate these will be needed when using these agents. Complement inhibitors could be an effective add-on strategy to antibody-depleting therapies but their role in AMR needs to be better defined. Combining proteasome inhibitors and costimulation blockers has shown encouraging results in the prevention of AMR in animal models and is now being investigated in humans. Other novel strategies such as Fc neonatal receptor blockers which inhibit the recycling of pathogenic IgG and bispecific antibodies against B-cell maturation antigen/CD3+ T cells warrant further investigation. SUMMARY There are now a number of emerging therapies with varied targets and mechanism(s) of action that hold promise in the management of AMR and improving allograft survival.
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Affiliation(s)
- Supreet Sethi
- Division of Nephrology, Department of Medicine, Comprehensive Transplant Center, Cedars Sinai Medical Center, Los Angeles, California, USA
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8
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Qi R, Qin W. Role of Complement System in Kidney Transplantation: Stepping From Animal Models to Clinical Application. Front Immunol 2022; 13:811696. [PMID: 35281019 PMCID: PMC8913494 DOI: 10.3389/fimmu.2022.811696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 01/31/2022] [Indexed: 12/23/2022] Open
Abstract
Kidney transplantation is a life-saving strategy for patients with end-stage renal diseases. Despite the advances in surgical techniques and immunosuppressive agents, the long-term graft survival remains a challenge. Growing evidence has shown that the complement system, part of the innate immune response, is involved in kidney transplantation. Novel insights highlighted the role of the locally produced and intracellular complement components in the development of inflammation and the alloreactive response in the kidney allograft. In the current review, we provide the updated understanding of the complement system in kidney transplantation. We will discuss the involvement of the different complement components in kidney ischemia-reperfusion injury, delayed graft function, allograft rejection, and chronic allograft injury. We will also introduce the existing and upcoming attempts to improve allograft outcomes in animal models and in the clinical setting by targeting the complement system.
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Affiliation(s)
| | - Weijun Qin
- Department of Urology, Xijing Hospital, Fourth Military Medical University, Xi’an, China
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9
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Tarandovskiy ID, Buehler PW, Karnaukhova E. C1-inhibitor influence on platelet activation by thrombin receptors agonists. Clin Appl Thromb Hemost 2022; 28:10760296221120422. [PMID: 35996317 PMCID: PMC9421059 DOI: 10.1177/10760296221120422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION Protease activated receptors 1 (PAR1) and 4 (PAR4) agonists are used to study platelet activation. Data on platelet activation are extrapolated across experimental settings. C1-inhibitor (C1INH) is a protease inhibitor present in plasma but not in isolated platelet suspensions. Here we show that C1INH affects platelet activation through PAR1 and PAR4 agonists. METHODS Platelets were isolated from healthy donor whole blood and then labeled with anti-CD62P and PAC1 antibodies. The platelet suspensions were exposed to PAR1 agonists SFLLRN, TFLLR and TFLLRN; PAR4 agonists AYPGKF and GYPGQV; ADP and thrombin. Flow-cytometric measurements were performed in 5, 10 and 15 min after activation. RESULTS 0.25 mg/ml C1INH addition made platelets to faster expose CD62P and glycoprotein IIb/IIIa complex after activation with PAR1 agonists. Conversely, C1INH addition led to inhibition of platelet activation with PAR4 agonists and thrombin. Activation with ADP was not affected by C1INH. CONCLUSIONS Our results suggest that C1INH can modify platelet activation in the presence of synthetic PAR agonists used in platelet research. These observations may be relevant to the development of new methods to assess platelet function.
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Affiliation(s)
- Ivan D Tarandovskiy
- Hemostasis Branch, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
| | - Paul W Buehler
- Department of Pathology and The Center for Blood Oxygen Transport and Hemostasis, Department of Pediatrics, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Elena Karnaukhova
- Laboratory of Biochemistry and Vascular Biology, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA
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Sethi S, Ammerman N, Vo A, Jordan SC. Approach to Highly Sensitized Kidney Transplant Candidates and a Positive Crossmatch. Adv Chronic Kidney Dis 2021; 28:587-595. [PMID: 35367027 DOI: 10.1053/j.ackd.2021.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 09/08/2021] [Indexed: 11/11/2022]
Abstract
Human leukocyte antigen (HLA)-incompatible kidney transplantation offers survival benefit compared with ongoing dialysis. There have been considerable advances in the last decade to allow for increased access to transplant for the HLA-sensitized kidney transplant candidates. These include increased priority in the kidney allocation system, kidney paired donation, and novel desensitization strategies. A better understanding of the role of B cells, plasma cells, and complement and inflammatory cytokines in the pathophysiology of HLA antibody-mediated allograft injury has led to the use of novel therapeutics for desensitization and treatment of antibody-mediated rejection. Here we discuss current approaches to kidney transplantation in HLA-sensitized kidney transplant candidates.
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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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Lai X, Zheng X, Mathew JM, Gallon L, Leventhal JR, Zhang ZJ. Tackling Chronic Kidney Transplant Rejection: Challenges and Promises. Front Immunol 2021; 12:661643. [PMID: 34093552 PMCID: PMC8173220 DOI: 10.3389/fimmu.2021.661643] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 04/27/2021] [Indexed: 01/09/2023] Open
Abstract
Despite advances in post-transplant management, the long-term survival rate of kidney grafts and patients has not improved as approximately forty percent of transplants fails within ten years after transplantation. Both immunologic and non-immunologic factors contribute to late allograft loss. Chronic kidney transplant rejection (CKTR) is often clinically silent yet progressive allogeneic immune process that leads to cumulative graft injury, deterioration of graft function. Chronic active T cell mediated rejection (TCMR) and chronic active antibody-mediated rejection (ABMR) are classified as two principal subtypes of CKTR. While significant improvements have been made towards a better understanding of cellular and molecular mechanisms and diagnostic classifications of CKTR, lack of early detection, differential diagnosis and effective therapies continue to pose major challenges for long-term management. Recent development of high throughput cellular and molecular biotechnologies has allowed rapid development of new biomarkers associated with chronic renal injury, which not only provide insight into pathogenesis of chronic rejection but also allow for early detection. In parallel, several novel therapeutic strategies have emerged which may hold great promise for improvement of long-term graft and patient survival. With a brief overview of current understanding of pathogenesis, standard diagnosis and challenges in the context of CKTR, this mini-review aims to provide updates and insights into the latest development of promising novel biomarkers for diagnosis and novel therapeutic interventions to prevent and treat CKTR.
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Affiliation(s)
- Xingqiang Lai
- Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
- Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
- Organ Transplant Center, the Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Xin Zheng
- Department of Urology, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - James M. Mathew
- Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
- Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Lorenzo Gallon
- Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
- Department of Medicine, Nephrology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Joseph R. Leventhal
- Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
- Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | - Zheng Jenny Zhang
- Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
- Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
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McRae JL, Vikstrom IB, Bongoni AK, Salvaris EJ, Fisicaro N, Ng M, Alhamdoosh M, Baz Morelli A, Cowan PJ, Pearse MJ. Blockade of the G-CSF Receptor Is Protective in a Mouse Model of Renal Ischemia–Reperfusion Injury. THE JOURNAL OF IMMUNOLOGY 2020; 205:1433-1440. [DOI: 10.4049/jimmunol.2000390] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 07/02/2020] [Indexed: 11/19/2022]
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Abstract
Complement plays important roles in both ischemia-reperfusion injury (IRI) and antibody-mediated rejection (AMR) of solid organ allografts. One approach to possibly improve outcomes after transplantation is the use of C1 inhibitor (C1-INH), which blocks the first step in both the classical and lectin pathways of complement activation and also inhibits the contact, coagulation, and kinin systems. C1-INH can also directly block leukocyte-endothelial cell adhesion. C1-INH contrasts with eculizumab and other distal inhibitors, which do not affect C4b or C3b deposition or noncomplement pathways. Authors of reports on trials in kidney transplant recipients have suggested that C1-INH treatment may reduce IRI and delayed graft function, based on decreased requirements for dialysis in the first month after transplantation. This effect was particularly marked with grafts with Kidney Disease Profile Index ≥ 85. Other clinical studies and models suggest that C1-INH may decrease sensitization and donor-specific antibody production and might improve outcomes in AMR, including in patients who are refractory to other modalities. However, the studies have been small and often only single-center. This article reviews clinical data and ongoing trials with C1-INH in transplant recipients, compares the results with those of other complement inhibitors, and summarizes potentially productive directions for future research.
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Franzin R, Stasi A, Fiorentino M, Stallone G, Cantaluppi V, Gesualdo L, Castellano G. Inflammaging and Complement System: A Link Between Acute Kidney Injury and Chronic Graft Damage. Front Immunol 2020; 11:734. [PMID: 32457738 PMCID: PMC7221190 DOI: 10.3389/fimmu.2020.00734] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 03/31/2020] [Indexed: 12/13/2022] Open
Abstract
The aberrant activation of complement system in several kidney diseases suggests that this pillar of innate immunity has a critical role in the pathophysiology of renal damage of different etiologies. A growing body of experimental evidence indicates that complement activation contributes to the pathogenesis of acute kidney injury (AKI) such as delayed graft function (DGF) in transplant patients. AKI is characterized by the rapid loss of the kidney's excretory function and is a complex syndrome currently lacking a specific medical treatment to arrest or attenuate progression in chronic kidney disease (CKD). Recent evidence suggests that independently from the initial trigger (i.e., sepsis or ischemia/reperfusions injury), an episode of AKI is strongly associated with an increased risk of subsequent CKD. The AKI-to-CKD transition may involve a wide range of mechanisms including scar-forming myofibroblasts generated from different sources, microvascular rarefaction, mitochondrial dysfunction, or cell cycle arrest by the involvement of epigenetic, gene, and protein alterations leading to common final signaling pathways [i.e., transforming growth factor beta (TGF-β), p16 ink4a , Wnt/β-catenin pathway] involved in renal aging. Research in recent years has revealed that several stressors or complications such as rejection after renal transplantation can lead to accelerated renal aging with detrimental effects with the establishment of chronic proinflammatory cellular phenotypes within the kidney. Despite a greater understanding of these mechanisms, the role of complement system in the context of the AKI-to-CKD transition and renal inflammaging is still poorly explored. The purpose of this review is to summarize recent findings describing the role of complement in AKI-to-CKD transition. We will also address how and when complement inhibitors might be used to prevent AKI and CKD progression, therefore improving graft function.
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Affiliation(s)
- Rossana Franzin
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
- Department Translational Medicine, University of Piemonte Orientale, Novara, Italy
| | - Alessandra Stasi
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Marco Fiorentino
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Giovanni Stallone
- Nephrology, Dialysis and Transplantation Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Vincenzo Cantaluppi
- Department Translational Medicine, University of Piemonte Orientale, Novara, Italy
| | - Loreto Gesualdo
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Giuseppe Castellano
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
- Nephrology, Dialysis and Transplantation Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
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16
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Kulkarni HS, Scozzi D, Gelman AE. Recent advances into the role of pattern recognition receptors in transplantation. Cell Immunol 2020; 351:104088. [PMID: 32183988 DOI: 10.1016/j.cellimm.2020.104088] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/05/2020] [Accepted: 03/06/2020] [Indexed: 12/19/2022]
Abstract
Pattern recognition receptors (PRRs) are germline-encoded sensors best characterized for their critical role in host defense. However, there is accumulating evidence that organ transplantation induces the release or display of molecular patterns of cellular injury and death that trigger PRR-mediated inflammatory responses. There are also new insights that indicate PRRs are able to distinguish between self and non-self, suggesting the existence of non-clonal mechanisms of allorecognition. Collectively, these reports have spurred considerable interest into whether PRRs or their ligands can be targeted to promote transplant survival. This review examines the mounting evidence that PRRs play in transplant-mediated inflammation. Given the large number of PRRs, we will focus on members from four families: the complement system, toll-like receptors, the formylated peptide receptor, and scavenger receptors through examining reports of their activity in experimental models of cellular and solid organ transplantation as well as in the clinical setting.
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Affiliation(s)
- Hrishikesh S Kulkarni
- Department of Medicine, Division of Pulmonary & Critical Care Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Davide Scozzi
- Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Andrew E Gelman
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO, USA; Department of Surgery, Division of Cardiothoracic Surgery, Washington University School of Medicine, St. Louis, MO, USA.
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17
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Schröppel B, Akalin E, Baweja M, Bloom RD, Florman S, Goldstein M, Haydel B, Hricik DE, Kulkarni S, Levine M, Mehrotra A, Patel A, Poggio ED, Ratner L, Shapiro R, Heeger PS. Peritransplant eculizumab does not prevent delayed graft function in deceased donor kidney transplant recipients: Results of two randomized controlled pilot trials. Am J Transplant 2020; 20:564-572. [PMID: 31452319 DOI: 10.1111/ajt.15580] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 07/25/2019] [Accepted: 08/12/2019] [Indexed: 01/25/2023]
Abstract
Animal models and observational human data indicate that complement, including C5a, pathogenically participates in ischemia reperfusion (IR) injury that manifests as delayed graft function (DGF) following deceased donor kidney transplantation. We report on the safety/efficacy of anti-C5 monoclonal antibody eculizumab (Ecu) administered in the operating room prior to reperfusion, to prevent DGF in recipients of deceased donor kidney transplants in two related, investigator-sponsored, randomized controlled trials. Eight recipients from a single center were enrolled in a pilot study that led to a 19-subject multicenter trial. Together, 27 deceased donor kidney transplant recipients, 16 Ecu-treated and 11 controls, were treated with rabbit antithymocyte globulin, tacrolimus, mycophenolate mofetil with or without glucocorticoids, and followed for 6 months. Data analysis showed no epidemiological or transplant-related differences between study arms. Ecu was well tolerated with a similar severe adverse event incidence between groups. The DGF rate did not differ between Ecu-treated (44%) and control (45%, P = 1.0) subjects. Serum creatinine reduction in the first week after transplantation, and graft function up to 180-days post-transplant, were also similar. Ecu administration was safe but did not reduce the rate of DGF in a high-risk population of deceased donor recipients.
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Affiliation(s)
- Bernd Schröppel
- Nephrology Division, Department of Medicine and Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, New York.,Section of Nephrology, University Hospital, Ulm, Germany
| | - Enver Akalin
- Nephrology Division, Department of Medicine, Montefiore Medical Center, Bronx, New York
| | - Mukta Baweja
- Nephrology Division, Department of Medicine and Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Roy D Bloom
- Renal-Electrolyte and Hypertension Division, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Sander Florman
- Recanati Miller Transplant Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Michael Goldstein
- Recanati Miller Transplant Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Brandy Haydel
- Recanati Miller Transplant Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Donald E Hricik
- University Hospitals Cleveland Medical Center, Cleveland, Ohio
| | - Sanjay Kulkarni
- Yale New Haven Transplant Center, Yale University School of Medicine, New Haven, Connecticut
| | - Matthew Levine
- Department of Surgery, Transplant Program, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Anita Mehrotra
- Nephrology Division, Department of Medicine and Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Anup Patel
- Saint Barnabas Medical Center, Livingston, New Jersey
| | - Emilio D Poggio
- Department of Nephrology and Hypertension, Cleveland Clinic, Cleveland, Ohio
| | - Lloyd Ratner
- Department of Surgery, Columbia University Medical Center, New York, New York
| | - Ron Shapiro
- Recanati Miller Transplant Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Peter S Heeger
- Nephrology Division, Department of Medicine and Translational Transplant Research Center, Icahn School of Medicine at Mount Sinai, New York, New York.,Recanati Miller Transplant Institute, Icahn School of Medicine at Mount Sinai, New York, New York
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Contradictory to its effects on thrombin, C1-inhibitor reduces plasmin generation in the presence of thrombomodulin. J Thromb Thrombolysis 2019; 48:81-87. [PMID: 31030323 DOI: 10.1007/s11239-019-01869-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
C1-inhibitor (C1INH) was shown to enhance thrombin generation (TG) in the presence of thrombomodulin (TM) by reducing production of activated protein C. Because C1INH is known to inhibit fibrinolytic system proteases, the objective of this study was to evaluate the effect of moderate (3 IU/ml) and high (16 IU/ml) C1INH concentrations on TG and plasmin generation (PG) in the presence of TM. These concentrations were evaluated based on expected maximum plasma levels following C1INH replacement therapy and recently suggested supraphysiologic dosing. TG and PG were investigated in platelet poor plasmas obtained from 21 healthy donors. An assay designed to monitor the continuous generation of the 7-amino-4-methylcoumarin fluorescence from substrates specific to thrombin or plasmin was used to evaluate the impact of C1INH activity. To characterize the C1INH effects on TG and PG, the thrombin and plasmin concentration peaks and production rates were calculated. TM addition to donor plasma shifted the concentration dependence of C1INH on TG parameters from reduction to enhancement. Conversely, PG parameters were significantly reduced by 16 IU/ml in both the presence and absence of TM. Moderate C1INH concentration (3 IU/ml) reduced TG and PG in the absence of TM but did not significantly affect these parameters in the presence of TM. Finally, 3 IU/ml of C1INH reduced PG more so than TG in the absence of TM. The presented results suggest a mechanism by which C1INH could potentiate thrombosis by inhibition of fibrinolysis.
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Huang E, Vo A, Choi J, Ammerman N, Lim K, Sethi S, Kim I, Kumar S, Najjar R, Peng A, Jordan SC. Three-Year Outcomes of a Randomized, Double-Blind, Placebo-Controlled Study Assessing Safety and Efficacy of C1 Esterase Inhibitor for Prevention of Delayed Graft Function in Deceased Donor Kidney Transplant Recipients. Clin J Am Soc Nephrol 2019; 15:109-116. [PMID: 31843975 PMCID: PMC6946080 DOI: 10.2215/cjn.04840419] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Accepted: 10/23/2019] [Indexed: 12/18/2022]
Abstract
BACKGROUND AND OBJECTIVES Delayed graft function is related to ischemia-reperfusion injury and may be complement dependent. We previously reported from a randomized, placebo-controlled trial that treatment with C1 esterase inhibitor was associated with a shorter duration of delayed graft function and higher eGFR at 1 year. Here, we report longer-term outcomes from this trial. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS This is a post hoc analysis of a phase 1/2, randomized, controlled trial enrolling 70 recipients of deceased donor kidney transplants at risk for delayed graft function (NCT02134314). Subjects were randomized to receive C1 esterase inhibitor 50 U/kg (n=35) or placebo (n=35) intraoperatively and at 24 hours. The cumulative incidence functions method was used to compare graft failure and death over 3.5 years. eGFR slopes were compared using a linear mixed effects model. RESULTS Three deaths occurred among C1 esterase inhibitor-treated patients compared with none receiving placebo. Seven graft failures developed in the placebo group compared with one among C1 esterase inhibitor-treated recipients; the cumulative incidence of graft failure was lower over 3.5 years among C1 esterase inhibitor-treated recipients compared with placebo (P=0.03). Although no difference in eGFR slopes was observed between groups (P for group-time interaction =0.12), eGFR declined in placebo-treated recipients (-4 ml/min per 1.73 m2 per year; 95% confidence interval, -8 to -0.1) but was stable in C1 esterase inhibitor-treated patients (eGFR slope: 0.5 ml/min per 1.73 m2 per year; 95% confidence interval, -4 to 5). At 3.5 years, eGFR was 56 ml/min per 1.73 m2 (95% confidence interval, 42 to 70) in the C1 esterase inhibitor group versus 35 ml/min per 1.73 m2 (95% confidence interval, 21 to 48) in the placebo group, with an estimated mean eGFR difference of 21 ml/min per 1.73 m2 (95% confidence interval, 2 to 41 ml/min per 1.73 m2). CONCLUSIONS Treatment of patients at risk for ischemia-reperfusion injury and delayed graft function with C1 esterase inhibitor was associated with a lower incidence of graft failure.
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Affiliation(s)
- Edmund Huang
- Division of Nephrology, Department of Medicine and
| | - Ashley Vo
- Division of Nephrology, Department of Medicine and
| | - Jua Choi
- Division of Nephrology, Department of Medicine and
| | | | - Kathlyn Lim
- Division of Nephrology, Department of Medicine and
| | | | - Irene Kim
- Department of Surgery, Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, California
| | | | - Reiad Najjar
- Division of Nephrology, Department of Medicine and
| | - Alice Peng
- Division of Nephrology, Department of Medicine and
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Abstract
Modification of pathogenic antibodies for autoimmune diseases illuminated the biologic relevance of B cells, plasma cells, and pathogenic antibodies in autoimmunity. They have also rejuvenated interest in how B cells mediate multiple effector functions that include antibody production, antigen presentation to T cells, costimulation, and the production of immune stimulating and immune modulatory cytokines. Repurposing these drugs from autoimmunity and cancer immunotherapy has yielded important advancements in the care of antibody-mediated rejection patients and novel drug development aimed at HLA desensitization have recently emerged. We now stand on an important threshold that promises many advances in the care of our allosensitized patients. We hope that these initial advances will encourage basic scientist, clinical investigators, industry, National Institutes of Health, our academic societies, and the Food and Drug Administration to continue support of these important objectives. These advances clearly have implications for sensitized patients receiving solid organ transplants and antibody-mediated rejection treatment. Modification of alloimmunity and alloantibodies will also have relevance to xenotransplantation where the xenoantibodies present a formidable obstacle to advancement of this important therapy. Working together, we can advance transplant therapeutics where biologic agents are likely to play novel and important roles. Here, we discuss novel drugs emerging in this area.
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Abstract
Because of the shortage of liver grafts available for transplantation, the restrictions on graft quality have been relaxed, and marginal grafts, such as steatotic livers, are now accepted. However, this policy change has not solved the problem, because steatotic liver grafts tolerate ischemia-reperfusion (I/R) injury poorly. Adipocytokines differentially modulate steatosis, inflammation, and fibrosis and are broadly present in hepatic resections and transplants. The potential use of adipocytokines as biomarkers of the severity of steatosis and liver damage to aid the identification of high-risk steatotic liver donors and to evaluate hepatic injury in the postoperative period are discussed. The hope of finding new therapeutic strategies aimed specifically at protecting steatotic livers undergoing surgery is a strong impetus for identifying the mechanisms responsible for hepatic failure after major surgical intervention. Hence, the most recently described roles of adipocytokines in steatotic livers subject to I/R injury are discussed, the conflicting results in the literature are summarized, and reasons are offered as to why strategic pharmacologic control of adipocytokines has yet to yield clinical benefits. After this, the next steps needed to transfer basic knowledge about adipocytokines into clinical practice to protect marginal livers subject to I/R injury are presented. Recent strategies based on adipocytokine regulation, which have shown efficacy in various pathologies, and hold promise for hepatic resection and transplantation are also outlined.
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22
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Böhmig GA, Eskandary F, Doberer K, Halloran PF. The therapeutic challenge of late antibody-mediated kidney allograft rejection. Transpl Int 2019; 32:775-788. [PMID: 30955215 PMCID: PMC6850109 DOI: 10.1111/tri.13436] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 03/06/2019] [Accepted: 04/01/2019] [Indexed: 01/01/2023]
Abstract
Late antibody‐mediated rejection (ABMR) is a cardinal cause of kidney allograft failure, manifesting as a continuous and, in contrast with early rejection, often clinically silent alloimmune process. While significant progress has been made towards an improved understanding of its molecular mechanisms and the definition of diagnostic criteria, there is still no approved effective treatment. In recent small randomized controlled trials, therapeutic strategies with promising results in observational studies, such as proteasome inhibitor bortezomib, anti‐C5 antibody eculizumab, or high dose intravenous immunoglobulin plus rituximab, had no significant impact in late and/or chronic ABMR. Such disappointing results reinforce a need of new innovative treatment strategies. Potential candidates may be the interference with interleukin‐6 to modulate B cell alloimmunity, or innovative compounds that specifically target antibody‐producing plasma cells, such as antibodies against CD38. Given the phenotypic heterogeneity of ABMR, the design of adequate systematic trials to assess the safety and efficiency of such therapies, however, is challenging. Several trials are currently being conducted, and new developments will hopefully provide us with effective ways to counteract the deleterious impact of antibody‐mediated graft injury. Meanwhile, the weight of evidence would suggest that, when approaching using existing treatments for established antibody‐mediated rejection, “less may be more”.
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Affiliation(s)
- Georg A Böhmig
- Division of Nephrology and Dialysis, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Farsad Eskandary
- Division of Nephrology and Dialysis, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Konstantin Doberer
- Division of Nephrology and Dialysis, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Philip F Halloran
- Alberta Transplant Applied Genomics Centre (ATAGC), University of Alberta, Edmonton, AB, Canada
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23
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Jordan SC, Choi J, Aubert O, Haas M, Loupy A, Huang E, Peng A, Kim I, Louie S, Ammerman N, Najjar R, Puliyanda D, Vo A. A phase I/II, double-blind, placebo-controlled study assessing safety and efficacy of C1 esterase inhibitor for prevention of delayed graft function in deceased donor kidney transplant recipients. Am J Transplant 2018; 18:2955-2964. [PMID: 29637714 DOI: 10.1111/ajt.14767] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 03/28/2018] [Accepted: 03/29/2018] [Indexed: 01/25/2023]
Abstract
Delayed graft function (DGF) is defined as need for dialysis early posttransplant. DGF is related to ischemia-reperfusion injury (IRI) that diminishes allograft function and may be complement dependent. Here, we investigate the ability of C1 esterase inhibitor (C1INH) to prevent IRI/DGF in kidney transplant recipients. Seventy patients receiving deceased donor kidney transplants at risk for DGF were randomized to receive C1INH 50 U/kg (#35) or placebo (#35) intraoperatively and at 24 hours. The primary end point was need for hemodialysis during the first week posttransplant. Assessments of glomerular filtration rate and dialysis dependence were accomplished. Complications and safety of therapy were recorded. Similar characteristics with no significant differences in cold-ischemia time or risk factors for DGF were seen. C1INH did not result in reduction of dialysis sessions at 1 week posttransplant, but significantly fewer dialysis sessions (P = .0232) were required 2 to 4 weeks posttransplant. Patients at highest risk for DGF (Kidney Donor Profile Index ≥85) benefited most from C1INH therapy. Significantly better renal function was seen at 1 year in C1INH patients (P = .006). No significant adverse events were noted with C1INH. Although the primary end point was not met, significant reductions in need for dialysis and improvements in long-term allograft function were seen with C1INH treatment.
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Affiliation(s)
- Stanley C Jordan
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Jua Choi
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Olivier Aubert
- Paris Translational Research Center for Organ Transplantation, INSERM U970, Biostatistics Department, Paris, France
| | - Mark Haas
- Department of Pathology, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Alexandre Loupy
- Paris Translational Research Center for Organ Transplantation, INSERM U970, Biostatistics Department, Paris, France
| | - Edmund Huang
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Alice Peng
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Irene Kim
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Sabrina Louie
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Noriko Ammerman
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Reiad Najjar
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Dechu Puliyanda
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Ashley Vo
- Comprehensive Transplant Center, Cedars-Sinai Medical Center, Los Angeles, CA
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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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25
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Current challenges and opportunities in the management of antibody-mediated rejection in lung transplantation. Curr Opin Organ Transplant 2018; 23:308-315. [DOI: 10.1097/mot.0000000000000537] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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26
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Castellano G, Franzin R, Stasi A, Divella C, Sallustio F, Pontrelli P, Lucarelli G, Battaglia M, Staffieri F, Crovace A, Stallone G, Seelen M, Daha MR, Grandaliano G, Gesualdo L. Complement Activation During Ischemia/Reperfusion Injury Induces Pericyte-to-Myofibroblast Transdifferentiation Regulating Peritubular Capillary Lumen Reduction Through pERK Signaling. Front Immunol 2018; 9:1002. [PMID: 29875766 PMCID: PMC5974049 DOI: 10.3389/fimmu.2018.01002] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 04/23/2018] [Indexed: 12/21/2022] Open
Abstract
Pericytes are one of the principal sources of scar-forming myofibroblasts in chronic kidneys disease. However, the modulation of pericyte-to-myofibroblast transdifferentiation (PMT) in the early phases of acute kidney injury is poorly understood. Here, we investigated the role of complement in inducing PMT after transplantation. Using a swine model of renal ischemia/reperfusion (I/R) injury, we found the occurrence of PMT after 24 h of I/R injury as demonstrated by reduction of PDGFRβ+/NG2+ cells with increase in myofibroblasts marker αSMA. In addition, PMT was associated with significant reduction in peritubular capillary luminal diameter. Treatment by C1-inhibitor (C1-INH) significantly preserved the phenotype of pericytes maintaining microvascular density and capillary lumen area at tubulointerstitial level. In vitro, C5a transdifferentiated human pericytes in myofibroblasts, with increased αSMA expression in stress fibers, collagen I production, and decreased antifibrotic protein Id2. The C5a-induced PMT was driven by extracellular signal-regulated kinases phosphorylation leading to increase in collagen I release that required both non-canonical and canonical TGFβ pathways. These results showed that pericytes are a pivotal target of complement activation leading to a profibrotic maladaptive cellular response. Our studies suggest that C1-INH may be a potential therapeutic strategy to counteract the development of PMT and capillary lumen reduction in I/R injury.
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Affiliation(s)
- Giuseppe Castellano
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Rossana Franzin
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Alessandra Stasi
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Chiara Divella
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Fabio Sallustio
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy.,Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Bari Aldo Moro, Bari, Italy
| | - Paola Pontrelli
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Giuseppe Lucarelli
- Urology, Andrology and Renal Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Michele Battaglia
- Urology, Andrology and Renal Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Staffieri
- Veterinary Surgery Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Antonio Crovace
- Veterinary Surgery Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Giovanni Stallone
- Nephrology, Dialysis and Transplantation Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Marc Seelen
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Centre Groningen, Groningen, Netherlands
| | - Mohamed R Daha
- Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Centre Groningen, Groningen, Netherlands.,Department of Nephrology, Leiden University Medical Centre, Leiden, Netherlands
| | - Giuseppe Grandaliano
- Nephrology, Dialysis and Transplantation Unit, Department of Medical and Surgical Sciences, University of Foggia, Foggia, Italy
| | - Loreto Gesualdo
- Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
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27
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Ali HA, Pavlisko EN, Snyder LD, Frank M, Palmer SM. Complement system in lung transplantation. Clin Transplant 2018; 32:e13208. [DOI: 10.1111/ctr.13208] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/10/2018] [Indexed: 12/27/2022]
Affiliation(s)
- Hakim Azfar Ali
- Division of Pulmonary, Allergy and Critical Care; Department of Medicine; Duke University Hospital; Durham NC USA
| | | | - Laurie D. Snyder
- Division of Pulmonary, Allergy and Critical Care; Department of Medicine; Duke University Hospital; Durham NC USA
| | - Michael Frank
- Department of Pediatrics; Duke University Hospital; Durham NC USA
| | - Scott M. Palmer
- Division of Pulmonary, Allergy and Critical Care; Department of Medicine; Duke University Hospital; Durham NC USA
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Muller YD, Ghaleb N, Rotman S, Vionnet J, Halfon M, Catana E, Golshayan D, Venetz JP, Aubert V, Pascual M. Rituximab as monotherapy for the treatment of chronic active antibody-mediated rejection after kidney transplantation. Transpl Int 2018; 31:451-455. [DOI: 10.1111/tri.13111] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Yannick D. Muller
- Transplantation Center; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
| | - Nseir Ghaleb
- Transplantation Center; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
| | - Samuel Rotman
- Service of Clinical Pathology; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
| | - Julien Vionnet
- Transplantation Center; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
| | - Matthieu Halfon
- Transplantation Center; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
| | - Emmanuelle Catana
- Transplantation Center; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
| | - Déla Golshayan
- Transplantation Center; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
| | - Jean-Pierre Venetz
- Transplantation Center; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
| | - Vincent Aubert
- Service of Immunology and Allergy; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
| | - Manuel Pascual
- Transplantation Center; Lausanne University Hospital; University of Lausanne; Lausanne Switzerland
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Chen H, Ambadapadi S, Dai E, Liu L, Yaron JR, Zhang L, Lucas A. Analysis of In Vivo Serpin Functions in Models of Inflammatory Vascular Disease. Methods Mol Biol 2018; 1826:157-182. [PMID: 30194600 DOI: 10.1007/978-1-4939-8645-3_11] [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] [Indexed: 06/08/2023]
Abstract
Serpins have a wide range of functions in regulation of serine proteases in the thrombotic cascade and in immune responses, representing up to 2-10% of circulating proteins in the blood. Selected serpins also have cross-class inhibitory actions for cysteine proteases in inflammasome and apoptosis pathways. The arterial and venous systems transport blood throughout the mammalian body representing a central site for interactions between coagulation proteases and circulating blood cells (immune cells) and target tissues, a very extensive and complex interaction. While analysis of serpin functions in vitro in kinetics or gel shift assays or in tissue culture provides very necessary information on molecular mechanisms, the penultimate assessment of biological or physiological functions and efficacy for serpins as therapeutics requires study in vivo in whole animal models (some also consider cell culture to be an in vivo approach).Mouse models of arterial transplant with immune rejection as well as models of inflammatory vasculitis induced by infection have been used to study the interplay between the coagulation and immune response pathways. We describe here three in vivo vasculitis models that are used to study the roles of serpins in disease and as therapeutics. The models described include (1) mouse aortic allograft transplantation, (2) human temporal artery (TA) xenograft into immunodeficient mouse aorta, and (3) mouse herpes virus (MHV68)-induced inflammatory vasculitis in interferon-gamma receptor (IFNγR) knockout mice.
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Affiliation(s)
- Hao Chen
- The Department of Tumor Surgery, Second Hospital of Lanzhou University, Lanzhou, China.
- The Key Laboratory of the Digestive System Tumors of Gansu Province, Lanzhou, Gansu, China.
| | - Sriram Ambadapadi
- Center for Personalized Diagnostics and Center for Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, AZ, USA
- Department of Medicine, Divisions of Cardiovascular Medicine and Rheumatology, University of Florida, Gainesville, FL, USA
| | - Erbin Dai
- Department of Surgery, BIDMC, Harvard Medical School, Boston, MA, USA
| | - Liying Liu
- Department of Surgery, BIDMC, Harvard Medical School, Boston, MA, USA
| | - Jordan R Yaron
- Centers for Personalized Diagnostics and Immunology, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, 727 E Tyler St, Tempe, AZ, 85287, USA
| | - Liqiang Zhang
- Center for Personalized Diagnostics and Center for Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Alexandra Lucas
- Center for Personalized Diagnostics and Center for Immunotherapy, Vaccines and Virotherapy, Biodesign Institute, Arizona State University, Tempe, AZ, USA
- Department of Medicine, Divisions of Cardiovascular Medicine and Rheumatology, University of Florida, Gainesville, FL, USA
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Chun N, Fairchild RL, Li Y, Liu J, Zhang M, Baldwin WM, Heeger PS. Complement Dependence of Murine Costimulatory Blockade-Resistant Cellular Cardiac Allograft Rejection. Am J Transplant 2017; 17:2810-2819. [PMID: 28444847 PMCID: PMC5912159 DOI: 10.1111/ajt.14328] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 04/03/2017] [Accepted: 04/20/2017] [Indexed: 01/25/2023]
Abstract
Building on studies showing that ischemia-reperfusion-(I/R)-injury is complement dependent, we tested links among complement activation, transplantation-associated I/R injury, and murine cardiac allograft rejection. We transplanted BALB/c hearts subjected to 8-h cold ischemic storage (CIS) into cytotoxic T-lymphocyte associated protein 4 (CTLA4)Ig-treated wild-type (WT) or c3-/- B6 recipients. Whereas allografts subjected to 8-h CIS rejected in WT recipients with a median survival time (MST) of 37 days, identically treated hearts survived >60 days in c3-/- mice (p < 0.05, n = 4-6/group). Mechanistic studies showed recipient C3 deficiency prevented induction of intragraft and serum chemokines/cytokines and blunted the priming, expansion, and graft infiltration of interferon-γ-producing, donor-reactive T cells. MST of hearts subjected to 8-h CIS was >60 days in mannose binding lectin (mbl1-/- mbl2-/- ) recipients and 42 days in factor B (cfb-/- ) recipients (n = 4-6/group, p < 0.05, mbl1-/- mbl2-/- vs. cfb-/- ), implicating the MBL (not alternative) pathway. To pharmacologically target MBL-initiated complement activation, we transplanted BALB/c hearts subjected to 8-h CIS into CTLA4Ig-treated WT B6 recipients with or without C1 inhibitor (C1-INH). Remarkably, peritransplantation administration of C1-INH prolonged graft survival (MST >60 days, p < 0.05 vs. controls, n = 6) and prevented CI-induced increases in donor-reactive, IFNγ-producing spleen cells (p < 0.05). These new findings link donor I/R injury to T cell-mediated rejection through MBL-initiated, complement activation and support testing C1-INH administration to prevent CTLA4Ig-resistant rejection of deceased donor allografts in human transplant patients.
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Affiliation(s)
- N Chun
- Department of Medicine, Translational Transplant Research Center, Recanati Miller Transplant Institute, Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - R L Fairchild
- Department of Immunology, Cleveland Clinic, Cleveland, OH
| | - Y Li
- Department of Medicine, Translational Transplant Research Center, Recanati Miller Transplant Institute, Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - J Liu
- Department of Medicine, Translational Transplant Research Center, Recanati Miller Transplant Institute, Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - M Zhang
- SUNY Downstate Medical Center, Brooklyn, NY
| | - W M Baldwin
- Department of Immunology, Cleveland Clinic, Cleveland, OH
| | - P S Heeger
- Department of Medicine, Translational Transplant Research Center, Recanati Miller Transplant Institute, Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY
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Blockade of HLA Antibody-Triggered Classical Complement Activation in Sera From Subjects Dosed With the Anti-C1s Monoclonal Antibody TNT009-Results from a Randomized First-in-Human Phase 1 Trial. Transplantation 2017; 101:2410-2418. [PMID: 28926521 PMCID: PMC5610566 DOI: 10.1097/tp.0000000000001804] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Background Complement may play a key role in antibody-mediated rejection. A promising therapeutic approach may be classical pathway (CP) inhibition at the level of early component C1. Methods In this first-in-human, double-blind, randomized placebo-controlled phase 1 trial, we evaluated the safety and complement inhibitory effect of TNT009, a humanized monoclonal anti-C1s antibody. Sixty-four adult healthy volunteers received either single (n = 48; 7 consecutive cohorts, 0.3-100 mg/kg) or 4 weekly infusions (n = 16; 2 consecutive cohorts, 30 and 60 mg/kg per infusion) of TNT009 or placebo. To assess the effect of treatment on complement activity, sera from dosed subjects were analyzed in a CP activation assay evaluating C3d deposition on HLA-coated microbeads spiked with alloantibodies. Results Single doses of TNT009 at 3 to 100 mg/kg uniformly and profoundly inhibited HLA antibody-mediated C3d deposition (≥86% after 60 minutes), whereby the duration of CP inhibition (2-14 days) was dose-dependent. Four weekly doses persistently blocked complement for 5 to 6 weeks. Ex vivo serum CP activity was profoundly inhibited when TNT009 concentrations exceeded 20 μg/mL. Infusions were well tolerated without serious or severe adverse events. Conclusions Treatment with TNT009 was safe and potently inhibited CP activity. Future studies in patients are required to assess the potential of TNT009 for preventing or treating antibody-mediated rejection. In a double-blind, randomized, placebo-controlled phase 1 trial in adult healthy volunteers, the authors report that TNT009, an anti-C1s monoclonal antibody, significantly inhibits complement classical pathway activation with an excellent tolerance.
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Inhibition of Complement. Transplantation 2017; 101:690-691. [DOI: 10.1097/tp.0000000000001624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Polyphosphate is a novel cofactor for regulation of complement by a serpin, C1 inhibitor. Blood 2016; 128:1766-76. [PMID: 27338096 DOI: 10.1182/blood-2016-02-699561] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 06/20/2016] [Indexed: 01/11/2023] Open
Abstract
The complement system plays a key role in innate immunity, inflammation, and coagulation. The system is delicately balanced by negative regulatory mechanisms that modulate the host response to pathogen invasion and injury. The serpin, C1-esterase inhibitor (C1-INH), is the only known plasma inhibitor of C1s, the initiating serine protease of the classical pathway of complement. Like other serpin-protease partners, C1-INH interaction with C1s is accelerated by polyanions such as heparin. Polyphosphate (polyP) is a naturally occurring polyanion with effects on coagulation and complement. We recently found that polyP binds to C1-INH, prompting us to consider whether polyP acts as a cofactor for C1-INH interactions with its target proteases. We show that polyP dampens C1s-mediated activation of the classical pathway in a polymer length- and concentration-dependent manner by accelerating C1-INH neutralization of C1s cleavage of C4 and C2. PolyP significantly increases the rate of interaction between C1s and C1-INH, to an extent comparable to heparin, with an exosite on the serine protease domain of the enzyme playing a major role in this interaction. In a serum-based cell culture system, polyP significantly suppressed C4d deposition on endothelial cells, generated via the classical and lectin pathways. Moreover, polyP and C1-INH colocalize in activated platelets, suggesting that their interactions are physiologically relevant. In summary, like heparin, polyP is a naturally occurring cofactor for the C1s:C1-INH interaction and thus an important regulator of complement activation. The findings may provide novel insights into mechanisms underlying inflammatory diseases and the development of new therapies.
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