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Stennett A, Friston K, Harris CL, Wollman AJM, Bronowska AK, Madden KS. The case for complement component 5 as a target in neurodegenerative disease. Expert Opin Ther Targets 2023; 27:97-109. [PMID: 36786123 DOI: 10.1080/14728222.2023.2177532] [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: 02/15/2023]
Abstract
INTRODUCTION Complement-based drug discovery is undergoing a renaissance, empowered by new advances in structural biology, complement biology and drug development. Certain components of the complement pathway, particularly C1q and C3, have been extensively studied in the context of neurodegenerative disease, and established as key therapeutic targets. C5 also has huge therapeutic potential in this arena, with its druggability clearly demonstrated by the success of C5-inhibitor eculizumab. AREAS COVERED We will discuss the evidence supporting C5 as a target in neurodegenerative disease, along with the current progress in developing different classes of C5 inhibitors and the gaps in knowledge that will help progress in the field. EXPERT OPINION Validation of C5 as a therapeutic target for neurodegenerative disease would represent a major step forward for complement therapeutics research and has the potential to furnish disease-modifying drugs for millions of patients suffering worldwide. Key hurdles that need to be overcome for this to be achieved are understanding how C5a and C5b should be targeted to bring therapeutic benefit and demonstrating the ability to target C5 without creating vulnerability to infection in patients. This requires greater biological elucidation of its precise role in disease pathogenesis, supported by better chemical/biological tools.
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Affiliation(s)
- Amelia Stennett
- School of Natural and Environmental Sciences, Newcastle University, NE1 7RU, Newcastle-Upon-Tyne, UK
| | - Kallie Friston
- School of Natural and Environmental Sciences, Newcastle University, NE1 7RU, Newcastle-Upon-Tyne, UK
| | - Claire L Harris
- Faculty of Medical Sciences, Newcastle University, NE2 4HH, Newcastle-Upon-Tyne, UK
| | - Adam J M Wollman
- Faculty of Medical Sciences, Newcastle University, NE2 4HH, Newcastle-Upon-Tyne, UK
| | - Agnieszka K Bronowska
- School of Natural and Environmental Sciences, Newcastle University, NE1 7RU, Newcastle-Upon-Tyne, UK
| | - Katrina S Madden
- School of Natural and Environmental Sciences, Newcastle University, NE1 7RU, Newcastle-Upon-Tyne, UK.,Faculty of Medical Sciences, Newcastle University, NE2 4HH, Newcastle-Upon-Tyne, UK
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2
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Li P, Hu S, Qian C, Yao Y, Li LY, Yang JF, Yang L, Yang CC, Zhou H, Wang SX, Hu Y, Zhu XY, Zhou J, Pan LX, Shen CP, Zhou H. The Therapeutic Effect of Traditional Chinese Medicine on Inflammatory Diseases Caused by Virus, Especially on Those Caused by COVID-19. Front Pharmacol 2021; 12:650425. [PMID: 34122073 PMCID: PMC8187915 DOI: 10.3389/fphar.2021.650425] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 03/29/2021] [Indexed: 12/19/2022] Open
Abstract
Inflammasomes are large multimolecular complexes best recognized because of their ability to control activation of caspase-1, which in turn regulates the maturation of interleukin-18 (IL-18) and interleukin-1 β (IL-1β). IL-1β was originally identified as a pro-inflammatory cytokine, capable of inducing local and systemic inflammation as well as a fever response reaction in response to infection or injury. Excessive production of IL-1β is related to inflammatory and autoimmune diseases. Both coronavirus disease 2019 (COVID-19) and severe acute respiratory syndrome (SARS) are characterized by excessive inflammatory response. For SARS, there is no correlation between viral load and worsening symptoms. However, there is no specific medicine which is available to treat the disease. As an important part of medical practice, TCM showed an obvious therapeutic effect in SARS-CoV-infected patients. In this article, we summarize the current applications of TCM in the treatment of COVID-19 patients. Herein, we also offer an insight into the underlying mechanisms of the therapeutic effects of TCM, as well as introduce new naturally occurring compounds with anti-coronavirus activity, in order to provide a new and potential drug development strategy for the treatment of COVID-19.
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Affiliation(s)
- Peng Li
- The First Affiliated Hospital of Medical University of Anhui, Hefei, China
| | - Shuang Hu
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Cheng Qian
- Center for Scientific Research, Anhui Medical University, Hefei, China
| | - Yan Yao
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Liang-Yun Li
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Jun-Fa Yang
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Li Yang
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Chen-Chen Yang
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Hong Zhou
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Shu-Xian Wang
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Ying Hu
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Xing-Yu Zhu
- National Drug Clinical Trial Institution, The First Affiliated Hospital of Bengbu Medical College, Hefei, China
| | - Jing Zhou
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Lin-Xin Pan
- School of Life Sciences, Anhui Medical University, Hefei, China
| | - Chuan-Pu Shen
- School of Pharmacy, Anhui Key Laboratory of Bioactivity of Natural Products, Anhui Medical University, Hefei, China.,Institute for Liver Diseases of Anhui Medical University, Anhui Medical University, Hefei, China
| | - Huan Zhou
- National Drug Clinical Trial Institution, The First Affiliated Hospital of Bengbu Medical College, Hefei, China
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Li Y, Zhao Q, Liu B, Dixon A, Cancio L, Dubick M, Dalle Lucca J. Early complementopathy predicts the outcomes of patients with trauma. Trauma Surg Acute Care Open 2019; 4:e000217. [PMID: 31058236 PMCID: PMC6461142 DOI: 10.1136/tsaco-2018-000217] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 02/08/2019] [Accepted: 02/28/2019] [Indexed: 01/04/2023] Open
Abstract
Background Complementopathy (rapid complement activation and consumption after trauma) has been reported in trauma patients, but the underlying mechanism of these phenomena and their clinical significance remain unclear. This study aimed to determine the complement/complement pathway activation and identify the association of complement activation with clinical outcomes in trauma patients. Methods We studied 33 trauma patients with mean Injury Severity Score of 25, and 25 healthy volunteers. Sera were collected on patients’ arrival at the emergency department, as well as 1, 2, 3, 5, and 7 days after trauma, to measure the levels of terminal complement activation product soluble C5b-9 (sC5b-9) by ELISA. In addition, the functional complement activation pathway was evaluated using a commercial complement system screening kit. Results Serum concentrations of sC5b-9 (complement terminal pathway activity) were significantly increased in trauma patients throughout the entire observation period except on day 1. Complement terminal activities were significantly higher in 27 of 33 patients with systemic inflammatory response syndrome (SIRS) than non-SIRS patients on day 2, day 5, and day 7. Increased serum levels of sC5b-9 positively correlated with SIRS. Functional complement analysis revealed that the classical pathway was the predominant pathway responsible for complement activation. Burn patients tended to have a greater and prolonged classical pathway activation than non-burn patients, and burn injury and blunt injury were associated with higher blood levels of sC5b-9 than penetrating injury. Discussion Early complement activation through the classical pathway after trauma is observed and positively correlated with the development of SIRS. Thus, monitoring of the complement system might be beneficial in the care of critically injured patients. Level of evidence III. Study type Prognostic.
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Affiliation(s)
- Yansong Li
- Multiple Organ Support Technology, US Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Qingwei Zhao
- Burn Research, US Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Bin Liu
- Blood Research, US Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Alexander Dixon
- Multiple Organ Support Technology, US Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Leopoldo Cancio
- Multiple Organ Support Technology, US Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Michael Dubick
- Damage Control Resuscitation, US Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Jurandir Dalle Lucca
- Viral Therapeutics, Chemical and Biological Technologies, Fort Belvoir, Virginia, USA
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4
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Shiu YL, Chiu KH, Huynh TG, Liu PC, Liu CH. Plasma immune protein analysis in the orange-spotted grouper Epinephelus coioides: Evidence for altered expressions of immune factors associated with a choline-supplemented diet. FISH & SHELLFISH IMMUNOLOGY 2017; 65:235-243. [PMID: 28454818 DOI: 10.1016/j.fsi.2017.04.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Revised: 04/21/2017] [Accepted: 04/24/2017] [Indexed: 06/07/2023]
Abstract
This study aimed to unravel the regulatory roles of choline in activating immune responses and disease resistance of the orange-spotted grouper Epinephelus coioides. Fish were fed a choline-supplemented diet at 1 g kg-1 of feed for 30 days. Fish fed a fish meal basal diet without choline-supplement served as controls. At the end of the feeding trial, fish were challenged with Vibrio alginolyticus. Meanwhile, plasma proteomics of fish in each group were also evaluated by two-dimensional gel electrophoresis (2-DE), and differentially expressed proteins were identified by tandem mass spectrophotometry (MS/MS), then a Western blot analysis or real-time polymerase chain reaction was used to confirm differential expressions of immune-enhancing proteins. Results showed that choline significantly increased survival of E. coioides 48 days after being injected with V. alginolyticus. From maps of plasma proteins, a comparative analysis between the control and choline groups revealed that 111 spots matched, with 26 altered expression spots in the choline group. Of these 26 spots, 16 were upregulated and 10 downregulated. After protein identification by reverse-phase nano-high-performance liquid chromatography-electrospray ionization MS/MS analysis, eight of 26 proteins were found to be immune-related proteins, all of which were upregulated, including complement 3 (C3), alpha-2-macroglobulin-P-like isoform (A2M), fibrinogen beta chain precursor (FBG), and immunoglobulin heavy constant mu (Ighm) proteins. Expression of the A2M protein and A2M enzyme activity in plasma of fish fed choline significantly increased compared to the control group. Additionally, A2M messenger (m)RNA transcripts were also upregulated in the liver and kidneys. Significantly higher C3 expressions at both the mRNA and protein levels were detected in the liver of fish in the choline group. Moreover, FBG gene expressions in the liver and kidneys significantly increased, while Ighm increased in the kidneys and spleen of fish in the choline group. Our results suggest that dietary administration of choline can protect grouper against bacterial infections through activating the complement system, thereby inducing antiprotease activity and natural antibodies that play important roles in the innate immune system of fish.
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Affiliation(s)
- Ya-Li Shiu
- Department of Aquaculture, National Pingtung University of Science and Technology, Pingtung, Taiwan
| | - Kuo-Hsun Chiu
- Department of Aquaculture, National Kaohsiung Marine University, Kaohsiung, Taiwan
| | - Truong-Giang Huynh
- Department of Aquaculture, National Pingtung University of Science and Technology, Pingtung, Taiwan; College of Aquaculture and Fisheries, CanTho University, CanTho, Vietnam
| | - Ping-Chung Liu
- Department of Aquaculture, National Taiwan Ocean University, Keelung, Taiwan
| | - Chun-Hung Liu
- Department of Aquaculture, National Pingtung University of Science and Technology, Pingtung, Taiwan.
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Yin X, Lu Y, Cheng ZH, Chen DF. Anti-Complementary Components of Helicteres angustifolia. Molecules 2016; 21:molecules21111506. [PMID: 27834928 PMCID: PMC6273495 DOI: 10.3390/molecules21111506] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 11/05/2016] [Accepted: 11/06/2016] [Indexed: 01/10/2023] Open
Abstract
A first phenalenon derivative with an acetyl side chain at C-8, 8-acetyl-9-hydroxy-3-methoxy-7-methyl-1-phenalenon (compound 1), and a pair of new sesquilignan epimers at C-7″ of hedyotol C and hedyotol D analogs, hedyotol C 7″-O-β-d-glucopyranoside (compound 2) and hedyotol D 7″-O-β-d-glucopyranoside (compound 3) were isolated from the aerial parts of Helicteres angustifolia together with nine known compounds (4–12). Their structures were elucidated on the basis of spectroscopic methods, including mass spectroscopy, and 1D and 2D nuclear magnetic resonance. Eleven isolates exhibited anti-complementary activity. In particular, compounds 4 and 5 exhibited potent anti-complementary activities against the classical and alternative pathways with CH50 values of 0.040 ± 0.009 and 0.009 ± 0.002 mM, and AP50 values of 0.105 ± 0.015 and 0.021 ± 0.003 mM, respectively. The targets of compounds 4 and 5 in the complement activation cascade were also identified. In conclusion, the anti-complementary components of H. angustifolia possessed chemical diversity and consisted mostly of flavonoids and lignans in this study.
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Affiliation(s)
- Xiang Yin
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China.
| | - Yan Lu
- Department of Pharmacognosy, School of Pharmacy, Fudan University, Shanghai 201203, China.
| | - Zhi-Hong Cheng
- Department of Pharmacognosy, School of Pharmacy, Fudan University, Shanghai 201203, China.
| | - Dao-Feng Chen
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China.
- Department of Pharmacognosy, School of Pharmacy, Fudan University, Shanghai 201203, China.
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6
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Zorzetto M, Ricevuti G, Martinetti M, Gritti D, Gasparetto C, De Silvestri A, Salvaneschi L, Cuccia M. HLA and Hypocomplementemia: The Disadvantage of Carrying the HLA-B35 and the Silent Alleles of the C4 Complement Component. Int J Immunopathol Pharmacol 2016; 17:307-16. [PMID: 15461865 DOI: 10.1177/039463200401700311] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Hypocomplementemia is an extremely complex phenomenon: we devoted our attention to its immunogenetic basis, particularly to the HLA haplotypes involved and to the study of C4 polymorphic genes. With this in mind we analyzed a group of unrelated patients with hypocomplementemia and 15 families suffering from specific C4 deficiency. Firstly, we performed a population analysis in order to identify a statistically significant association: HLA-B35 and C4BQ0 alleles, in the total group of hypocomplementemic individuals, seem to be associated with the primary disease. Secondly, we defined HLA haplotypes clear-cut segregation in the hypocomplementemic families and we identified the most common HLA haplotypes carrying B35 and C4 null allele associated with this condition. With the aid of correspondence analysis and the Transmission Disequilibrium Test (TDT), we measured the strength of this association. In this work, mainly through family analysis, we envisaged a potentially interesting genomic trait, within HLA, close to B locus, that seems to be involved in hypocomplementemia itself and perhaps in hypocomplementemia-related disorders.
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Affiliation(s)
- M Zorzetto
- Laboratorio di Biochimica e Genetica, Clinica Malattie Respiratorie, IRCCS Policlinico S.Matteo, Universitá di Pavia, Italy
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7
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Panda S, Ding JL. Natural antibodies bridge innate and adaptive immunity. THE JOURNAL OF IMMUNOLOGY 2016; 194:13-20. [PMID: 25527792 DOI: 10.4049/jimmunol.1400844] [Citation(s) in RCA: 202] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Natural Abs, belonging to isotypes IgM, IgG3, and IgA, were discovered nearly half a century ago. Despite knowledge about the role of the polyreactive natural IgM in pathogen elimination, B cell survival and homeostasis, inflammatory diseases, and autoimmunity, there is a lack of clarity about the physiological role of natural IgG and natural IgA because they appear incapable of recognizing Ags on their own and are perceived as nonreactive. However, recent research revealed exciting functions of natural IgG in innate immunity. Natural IgG:lectin collaboration swiftly and effectively kills invading pathogens. These advances prompt further examination of natural Abs in immune defense and homeostasis, with the potential for developing novel therapeutics. This review provides new insights into the interaction between natural Abs and lectins, with implications on how interactions between molecules of the innate and adaptive immune systems bridge these two arms of immunity.
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Affiliation(s)
- Saswati Panda
- Department of Biological Sciences, National University of Singapore, Singapore 117543
| | - Jeak L Ding
- Department of Biological Sciences, National University of Singapore, Singapore 117543
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8
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Mahajan SD, Parikh NU, Woodruff TM, Jarvis JN, Lopez M, Hennon T, Cunningham P, Quigg RJ, Schwartz SA, Alexander JJ. C5a alters blood-brain barrier integrity in a human in vitro model of systemic lupus erythematosus. Immunology 2015; 146:130-43. [PMID: 26059553 DOI: 10.1111/imm.12489] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 05/27/2015] [Accepted: 06/01/2015] [Indexed: 12/23/2022] Open
Abstract
The blood-brain barrier (BBB) plays a crucial role in brain homeostasis, thereby maintaining the brain environment precise for optimal neuronal function. Its dysfunction is an intriguing complication of systemic lupus erythematosus (SLE). SLE is a systemic autoimmune disorder where neurological complications occur in 5-50% of cases and is associated with impaired BBB integrity. Complement activation occurs in SLE and is an important part of the clinical profile. Our earlier studies demonstrated that C5a generated by complement activation caused the loss of brain endothelial layer integrity in rodents. The goal of the current study was to determine the translational potential of these studies to a human system. To assess this, we used a two dimensional in vitro BBB model constructed using primary human brain microvascular endothelial cells and astroglial cells, which closely emulates the in vivo BBB allowing the assessment of BBB integrity. Increased permeability monitored by changes in transendothelial electrical resistance and cytoskeletal remodelling caused by actin fiber rearrangement were observed when the cells were exposed to lupus serum and C5a, similar to the observations in mice. In addition, our data show that C5a/C5aR1 signalling alters nuclear factor-κB translocation into nucleus and regulates the expression of the tight junction proteins, claudin-5 and zonula occludens 1 in this setting. Our results demonstrate for the first time that C5a regulates BBB integrity in a neuroinflammatory setting where it affects both endothelial and astroglial cells. In addition, we also demonstrate that our previous findings in a mouse model, were emulated in human cells in vitro, bringing the studies one step closer to understanding the translational potential of C5a/C5aR1 blockade as a promising therapeutic strategy in SLE and other neurodegenerative diseases.
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Affiliation(s)
| | - Neil U Parikh
- Department of Medicine, University at Buffalo, Buffalo, NY, USA
| | - Trent M Woodruff
- School of Biomedical Sciences, University of Queensland, St. Lucia, QLD, Australia
| | - James N Jarvis
- Department of Pediatrics, University at Buffalo, Buffalo, NY, USA
| | - Molly Lopez
- Department of Pediatrics, University at Buffalo, Buffalo, NY, USA
| | - Teresa Hennon
- Department of Medicine, University at Buffalo, Buffalo, NY, USA
| | | | - Richard J Quigg
- Department of Medicine, University at Buffalo, Buffalo, NY, USA
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Abstract
The complement system is an essential component of the immune system. It is a highly integrative system and has a number of functions, including host defense, removal of injured cells and debris, modulation of metabolic and regenerative processes, and regulation of adaptive immunity. Complement is activated via different pathways and it is regulated tightly by several mechanisms to prevent host injury. Imbalance between complement activation and regulation can manifest in disease and injury to self. This article provides an outline of complement activation pathways, regulatory mechanisms, and normal physiologic functions of the system.
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Affiliation(s)
- Juan Carlos Varela
- Division of Hematology, Department of Medicine, Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Stephen Tomlinson
- Department of Microbiology and Immunology, Ralph H. Johnson Veterans Affairs Medical Center, Medical University of South Carolina, Charleston, SC, USA.
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10
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Mamidi S, Höne S, Teufel C, Sellner L, Zenz T, Kirschfink M. Neutralization of membrane complement regulators improves complement-dependent effector functions of therapeutic anticancer antibodies targeting leukemic cells. Oncoimmunology 2015; 4:e979688. [PMID: 25949896 PMCID: PMC4404820 DOI: 10.4161/2162402x.2014.979688] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 10/16/2014] [Accepted: 10/16/2014] [Indexed: 01/12/2023] Open
Abstract
Complement-dependent cytotoxicity (CDC) is one of the effector mechanisms mediated by therapeutic anticancer monoclonal antibodies (mAbs). However, the efficacy of antibodies is limited by the resistance of malignant cells to complement attack, primarily due to the over-expression of one or more membrane complement regulatory proteins (mCRPs) CD46, CD55, and CD59. CD20-positive Burkitt lymphoma Raji cells and primary CLL cells are resistant to rituximab (RTX)-induced CDC whereas ofatumumab (OFA) proved to be more efficient in cell killing. Primary CLL cells but not CD52-positive acute lymphoblastic leukemia (ALL) REH cells were sensitive to alemtuzumab (ALM)-induced CDC. Upon combined inhibition on Raji and CLL cells by mCRPs-specific siRNAs or neutralizing antibodies, CDC induced by RTX and by OFA was augmented. Similarly, CDC of REH cells was enhanced after mCRPs were inhibited upon treatment with ALM. All mAbs induced C3 opsonization, which was significantly augmented upon blocking mCRPs. C3 opsonization led to enhanced cell-mediated cytotoxicity of leukemia cells exposed to PBLs or macrophages. Furthermore, opsonized CLL cells were efficiently phagocytized by macrophages. Our results provide conclusive evidence that inhibition of mCRPs expression sensitizes leukemic cells to complement attack thereby enhancing the therapeutic effect of mAbs targeting leukemic cells.
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Key Words
- ADCC, antibody-dependent cellular cytotoxicity
- ALM, Alemtuzumab
- CDC, complement-dependent cytotoxicity
- CDCC, complement-dependent cellular cytotoxicity
- MAC, membrane attack complex
- NHS, Normal Human Serum
- OFA, Ofatumumab
- PBLs, peripheral blood leukocytes
- RTX, Rituximab
- TRX, Trastuzumab
- alemtuzumab
- chronic lymphocytic leukemia
- complement regulatory proteins
- complement-dependent cytotoxicity
- mCRP, membrane-bound complement regulatory protein
- ofatumumab
- opsonization
- rituximab
- siRNA, small interfering RNA
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Affiliation(s)
- Srinivas Mamidi
- Institute for Immunology; University of Heidelberg; Heidelberg, Germany
| | - Simon Höne
- Institute for Immunology; University of Heidelberg; Heidelberg, Germany
| | - Claudia Teufel
- Institute for Immunology; University of Heidelberg; Heidelberg, Germany
| | - Leopold Sellner
- Department of Translational Oncology; National Center for Tumour Diseases (NCT) and German Cancer Research Center (DKFZ); Heidelberg, Germany
- Department of Medicine V; University of Heidelberg; Heidelberg, Germany
| | - Thorsten Zenz
- Department of Translational Oncology; National Center for Tumour Diseases (NCT) and German Cancer Research Center (DKFZ); Heidelberg, Germany
- Department of Medicine V; University of Heidelberg; Heidelberg, Germany
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11
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Thurman JM, Tchepeleva SN, Haas M, Panzer S, Boackle SA, Glogowska MJ, Quigg RJ, Holers VM. Complement alternative pathway activation in the autologous phase of nephrotoxic serum nephritis. Am J Physiol Renal Physiol 2012; 302:F1529-36. [PMID: 22492944 DOI: 10.1152/ajprenal.00422.2011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The complement cascade is an important part of the innate immune system, but pathological activation of this system causes tissue injury in several autoimmune and inflammatory diseases, including immune complex glomerulonephritis. We examined whether mice with targeted deletion of the gene for factor B (fB(-/-) mice) and selective deficiency in the alternative pathway of complement are protected from injury in the nephrotoxic serum (NTS) nephritis model of antibody-mediated glomerulonephritis. When the acute affects of the anti-glomerular basement membrane antibody were assessed, fB(-/-) mice developed a degree of injury similar to wild-type controls. If the mice were presensitized with sheep IgG or if the mice were followed for 5 mo postinjection, however, the fB(-/-) mice developed milder injury than wild-type mice. The immune response of fB(-/-) mice exposed to sheep IgG was similar to that of wild-type mice, but the fB(-/-) mice had less glomerular C3 deposition and lower levels of albuminuria. These results demonstrate that fB(-/-) mice are not significantly protected from acute heterologous injury in NTS nephritis but are protected from autologous injury in response to a planted glomerular antigen. Thus, although the glomerulus is resistant to antibody-initiated, alternative pathway-mediated injury, inhibition of this complement pathway may be beneficial in chronic immune complex-mediated diseases.
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Affiliation(s)
- Joshua M Thurman
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado 80045, USA.
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12
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Jacob A, Hack B, Chen P, Quigg RJ, Alexander JJ. C5a/CD88 signaling alters blood-brain barrier integrity in lupus through nuclear factor-κB. J Neurochem 2011; 119:1041-51. [PMID: 21929539 DOI: 10.1111/j.1471-4159.2011.07490.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Inflammation is a key factor in a number of neurodegenerative diseases including systemic lupus erythematosus. The complement system is an important mechanism in initiating and amplifying inflammation. Our recent studies demonstrate that C5a, a protein fragment generated during complement activation could alter the blood-brain barrier integrity, and thereby disturb the brain microenvironment. To understand the mechanism by which this occurs, we examined the effects of C5a on apoptosis, translocation of nuclear factor-κB (NF-κb) and the expression of Iκbα, MAPK, CREB and TJ protein, zona occludens (ZO-1) in mouse brain endothelial cells. Apoptosis was examined by DNA laddering and caspase 3 activity and the distribution of the ZO-1 and the p65 subunit of NF-κB were determined by immunofluorescence. Inhibition of CD88 reduced translocation of NF-κb into the nucleus, altered ZO-1 at the interfaces of neighboring cells, decreased caspase 3 activity and prevented apoptosis in these cells. Our results indicate that signaling through CD88 regulates the blood-brain barrier in a NF-κb-dependent manner. These studies suggest that the C5a receptor, CD88 is a promising therapeutic target that will reduce NF-κb-signaling cascades in inflammatory settings.
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Affiliation(s)
- Alexander Jacob
- Department of Medicine, University of Chicago, Chicago, Illinois, USA
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13
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Innate Immunity and Host Defense against Microbial Infection. Mol Microbiol 2011. [DOI: 10.1128/9781555816834.ch54] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Jacob A, Hack B, Bai T, Brorson JR, Quigg RJ, Alexander JJ. Inhibition of C5a receptor alleviates experimental CNS lupus. J Neuroimmunol 2010; 221:46-52. [PMID: 20207017 DOI: 10.1016/j.jneuroim.2010.02.011] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 02/11/2010] [Accepted: 02/11/2010] [Indexed: 12/11/2022]
Abstract
To investigate the role of C5a generated on complement activation in brain, the lupus model, MRL/lpr mice were treated with C5a receptor(R) antagonist (ant). Neutrophil infiltration, ICAM, TNF-alpha and iNOS mRNA expression, neuronal apoptosis and the expression of p-JNK, pSTAT1 and p-Erk were reduced and p-Akt increased on C5aR inhibition in MRL/lpr brains. MRL/lpr serum caused increased apoptosis in neurons showing that lupus had a direct effect on these cells. C5aRant pretreatment prevented the lupus serum induced loss of neuronal cells. Our findings demonstrate for the first time that C5a/C5aR signaling plays an important role in the pathogenesis of CNS lupus.
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Affiliation(s)
- Alexander Jacob
- Department of Medicine, University of Chicago, Chicago, IL 60637, USA.
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15
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Jacob A, Hack B, Chiang E, Garcia JGN, Quigg RJ, Alexander JJ. C5a alters blood-brain barrier integrity in experimental lupus. FASEB J 2010; 24:1682-8. [PMID: 20065106 DOI: 10.1096/fj.09-138834] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The blood-brain barrier (BBB) is a crucial anatomic location in the brain. Its dysfunction complicates many neurodegenerative diseases, from acute conditions, such as sepsis, to chronic diseases, such as systemic lupus erythematosus (SLE). Several studies suggest an altered BBB in lupus, but the underlying mechanism remains unknown. In the current study, we observed a definite loss of BBB integrity in MRL/MpJ-Tnfrsf6(lpr) (MRL/lpr) lupus mice by IgG infiltration into brain parenchyma. In line with this result, we examined the role of complement activation, a key event in this setting, in maintenance of BBB integrity. Complement activation generates C5a, a molecule with multiple functions. Because the expression of the C5a receptor (C5aR) is significantly increased in brain endothelial cells treated with lupus serum, the study focused on the role of C5a signaling through its G-protein-coupled receptor C5aR in brain endothelial cells, in a lupus setting. Reactive oxygen species production increased significantly in endothelial cells, in both primary cells and the bEnd3 cell line treated with lupus serum from MRL/lpr mice, compared with those treated with control serum from MRL(+/+) mice. In addition, increased permeability monitored by changes in transendothelial electrical resistance, cytoskeletal remodeling caused by actin fiber rearrangement, and increased iNOS mRNA expression were observed in bEnd3 cells. These disruptive effects were alleviated by pretreating cells with a C5a receptor antagonist (C5aRant) or a C5a antibody. Furthermore, the structural integrity of the vasculature in MRL/lpr brain was maintained by C5aR inhibition. These results demonstrate the regulation of BBB integrity by the complement system in a neuroinflammatory setting. For the first time, a novel role of C5a in the maintenance of BBB integrity is identified and the potential of C5a/C5aR blockade highlighted as a promising therapeutic strategy in SLE and other neurodegenerative diseases.
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Affiliation(s)
- Alexander Jacob
- Department of Medicine, University of Chicago, Chicago, IL 60637, USA
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16
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Activation of innate and humoral immunity in the peripheral nervous system of ALS transgenic mice. Proc Natl Acad Sci U S A 2009; 106:20960-5. [PMID: 19933335 DOI: 10.1073/pnas.0911405106] [Citation(s) in RCA: 154] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
During injury to the nervous system, innate immune cells mediate phagocytosis of debris, cytokine production, and axon regeneration. In the neuro-degenerative disease amyotrophic lateral sclerosis (ALS), innate immune cells in the CNS are activated. However, the role of innate immunity in the peripheral nervous system (PNS) has not been well defined. In this study, we characterized robust activation of CD169/CD68/Iba1+ macrophages throughout the PNS in mutant SOD1(G93A) and SOD1(G37R) transgenic mouse models of ALS. Macrophage activation occurred pre-symptomatically, and expanded from focal arrays within nerve bundles to a tissue-wide distribution following symptom onset. We found a striking dichotomy for immune cells within the spinal cord and PNS. Flow cytometry and GFP bone marrow chimeras showed that spinal cord microglia were mainly tissue resident derived, dendritic-like cells, whereas in peripheral nerves, the majority of activated macrophages infiltrated from the circulation. Humoral antibodies and complement localized to PNS tissue in tandem with macrophage recruitment, and deficiency in complement C4 led to decreased macrophage activation. Therefore, cross-talk between nervous and immune systems occurs throughout the PNS during ALS disease progression. These data reveal a progressive innate and humoral immune response in peripheral nerves that is separate and distinct from spinal cord immune activation in ALS transgenic mice.
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Nakayama Y, Kim SI, Kim EH, Lambris JD, Sandor M, Suresh M. C3 promotes expansion of CD8+ and CD4+ T cells in a Listeria monocytogenes infection. THE JOURNAL OF IMMUNOLOGY 2009; 183:2921-31. [PMID: 19648268 DOI: 10.4049/jimmunol.0801191] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
It is known that C3 is required for optimal expansion of T cells during acute viral infections. However, it is not yet determined whether T cell responses to intracellular bacterial infections require C3. Therefore, we have investigated the requirement for C3 to elicit potent T cell responses to Listeria monocytogenes (LM). We show that expansion of Ag-specific CD8 and CD4 T cells during a primary response to LM was markedly reduced in the absence of C3 activity. Further studies indicated that, unlike in an influenza virus infection, the regulation of LM-specific T cell responses by C3 might not involve the downstream effector C5a. Moreover, reduced T cell responses to LM was not linked to defective maturation of dendritic cells or developmental anomalies in the peripheral T cell compartment of C3-deficient mice. Experiments involving adoptive transfer of C3-deficient CD8 T cells into the C3-sufficient environment of wild-type mice showed that these T cells do not have intrinsic proliferative defects, and a paracrine source of C3 will suffice for clonal expansion of CD8 T cells in vivo. However, stimulation of purified C3-deficient CD8 T cells by plastic-immobilized anti-CD3 showed that C3 promotes T cell proliferation directly, independent of its effects on APC. On the basis of these findings, we propose that diminished T cell responses to LM in C3-deficient mice might be at least in part due to lack of direct effects of C3 on T cells. These studies have furthered our understanding of C3-mediated regulation of T cell immunity to intracellular pathogens.
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Affiliation(s)
- Yumi Nakayama
- Department of Pathobiological Sciences, University of Wisconsin, Madison, WI 53706, USA
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18
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Fernandez Gonzalez S, Jayasekera JP, Carroll MC. Complement and natural antibody are required in the long-term memory response to influenza virus. Vaccine 2009; 26 Suppl 8:I86-93. [PMID: 19388171 DOI: 10.1016/j.vaccine.2008.11.057] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Complement, complement receptors and natural antibody (IgM) are important factors in the immune response against pathogens. Previous studies have indicated a role for C3, the complement receptors CD35/CD21 (CR1/CR2), and IgM in the immune response to influenza virus. Nevertheless, their contribution to the long-term memory response to this pathogen remains unknown. To elucidate this role, we characterized the secondary response on mice deficient of CR1/CR2 (Cr2-/-), C3 (C3-/-), secreted IgM (micros-/-) and the double knockout C3-/-micros-/-. Overall, our results suggest that C3, IgM and CR1/CR2 play crucial roles in the maintenance of long-term memory to influenza virus, possibly through the development of memory B cells and long-term antibody secretion.
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Affiliation(s)
- Santiago Fernandez Gonzalez
- Immune Disease Institute and Department of Pediatrics and Pathology, Harvard Medical School, 800 Huntington Avenue, Boston, MA 02115, USA
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20
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Zhang T, Chen D. Anticomplementary principles of a Chinese multiherb remedy for the treatment and prevention of SARS. JOURNAL OF ETHNOPHARMACOLOGY 2008; 117:351-61. [PMID: 18400428 PMCID: PMC7126446 DOI: 10.1016/j.jep.2008.02.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Revised: 12/20/2007] [Accepted: 02/02/2008] [Indexed: 05/19/2023]
Abstract
AIM OF THE STUDY To elucidate the anticomplementary principles of a Chinese multiherb remedy used for the treatment and prevention of SARS, which contains five ingredients of Herba Houttuyniae, Flos Chrysanthemi Indici, Herba Artemisiae Scopariae, Herba Eupatorii and Fructus Tsaoko. MATERIALS AND METHODS The anticomplementary activity was evaluated from hemolytic assays through the classical pathway (CP) and the alternative pathway (AP) of complement system in vitro. Compounds were isolated using bioactivity-guided fractionation and tested in vitro for their complement-inhibiting properties on the CP and AP. HPLC-DAD-ESI-MS was used to assign the isolated compounds in the five ingredient herbs. RESULTS 15 compounds, including chlorogenic acid (1), rutin (2), hyperoside (3), p-hydroxyacephenone (4), scopoletin (5), quercitrin (6) (3R,4R,6S)-3,6-dihydroxy-1-menthene (7), acaciin (8), scoparone (9), luteolin (10), quercetin (11), apigenin (12), acacetin (13), aristolactam (14), and apigenin-7,4'-dimethyl ether (15) were isolated and identified. Nine flavonoids (2, 3, 6, 8, 10-13, 15) were found to show inhibitory effects towards the CP and AP of complement system, luteolin (10) was the most potent with the CH50 and AP50 values of 0.19 and 0.17 mM. The bioactive flavonoids were mainly derived from Herba Houttuyniae, Flos Chrysanthemi Indici and Herba Artemisiae Scopariae. CONCLUSIONS A Chinese multiherb remedy used for the treatment and prevention of SARS has robust inhibitory effect on complement system through the CP and AP, and its anticomplementary activity could be attributed to the flavonoids present in some ingredient herbs. Luteolin could be a potential anticomplementary agent.
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Affiliation(s)
- Ting Zhang
- Department of Pharmacognosy, School of Pharmacy, Fudan University, 138 Yixueyuan Road, Shanghai 200032, China
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21
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Complement C3d conjugation to anthrax protective antigen promotes a rapid, sustained, and protective antibody response. PLoS One 2007; 2:e1044. [PMID: 17940608 PMCID: PMC2001179 DOI: 10.1371/journal.pone.0001044] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2007] [Accepted: 09/11/2007] [Indexed: 11/19/2022] Open
Abstract
B. anthracis is the causative agent of anthrax. Pathogenesis is primarily mediated through the exotoxins lethal factor and edema factor, which bind protective antigen (PA) to gain entry into the host cell. The current anthrax vaccine (AVA, Biothrax™) consists of aluminum-adsorbed cell-free filtrates of unencapsulated B. anthracis, wherein PA is thought to be the principle target of neutralization. In this study, we evaluated the efficacy of the natural adjuvant, C3d, versus alum in eliciting an anti-PA humoral response and found that C3d conjugation to PA and emulsion in incomplete Freund's adjuvant (IFA) imparted superior protection from anthrax challenge relative to PA in IFA or PA adsorbed to alum. Relative to alum-PA, immunization of mice with C3d-PA/IFA augmented both the onset and sustained production of PA-specific antibodies, including neutralizing antibodies to the receptor-binding portion (domain 4) of PA. C3d-PA/IFA was efficacious when administered either i.p. or s.c., and in adolescent mice lacking a fully mature B cell compartment. Induction of PA-specific antibodies by C3d-PA/IFA correlated with increased efficiency of germinal center formation and plasma cell generation. Importantly, C3d-PA immunization effectively protected mice from intranasal challenge with B. anthracis spores, and was approximately 10-fold more effective than alum-PA immunization or PA/IFA based on dose challenge. These data suggest that incorporation of C3d as an adjuvant may overcome shortcomings of the currently licensed aluminum-based vaccine, and may confer protection in the early days following acute anthrax exposure.
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23
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Young KA, Chen XS, Holers VM, Hannan JP. Isolating the Epstein-Barr virus gp350/220 binding site on complement receptor type 2 (CR2/CD21). J Biol Chem 2007; 282:36614-25. [PMID: 17925391 DOI: 10.1074/jbc.m706324200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Complement receptor type 2 (CR2/CD21) is essential for the attachment of Epstein-Barr virus (EBV) to the surface of B-lymphocytes in an interaction mediated by the viral envelope glycoprotein gp350. The heavily glycosylated structure of EBV gp350 has recently been elucidated by x-ray crystallography, and the CR2 binding site on this protein has been characterized. To identify the corresponding gp350 binding site on CR2, we have undertaken a site-directed mutagenesis study targeting regions of CR2 that have previously been implicated in the binding of CR2 to the C3d/C3dg fragments of complement component C3. Wild-type or mutant forms of CR2 were expressed on K562 cells, and the ability of these CR2-expressing cells to bind gp350 was measured using flow cytometry. Mutations directed toward the two N-terminal extracellular domains of CR2 (SCR1-2) reveal that a large contiguous surface of CR2 SCR1-2 is involved in gp350 binding, including a number of positively charged residues (Arg-13, (Arg-28, (Arg-36, Lys-41, Lys-57, Lys-67, and Arg-83). These data appear to complement the CR2 binding site on gp350, which is characterized by a preponderance of negative charge. In addition to identifying the importance of charge in the formation of a CR2-gp350 complex, we also provide evidence that both SCR1 and SCR2 make contact with gp350. Specifically, two anti-CR2 monoclonal antibodies, designated as monoclonal antibodies 171 and 1048 whose primary epitopes are located within SCR2, inhibit binding of wild-type CR2 to EBV gp350; with regard to SCR1, both K562 cells expressing an S15P mutation and recombinant S15P CR2 proteins exhibit diminished gp350 binding.
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Affiliation(s)
- Kendra A Young
- Department of Medicine and Immunology, University of Colorado at Denver and Health Sciences Center, Aurora, Colorado 80045, USA
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24
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Kozlov LV, Burdelev OO, Bureeva SV, Kaplun AP. Artificial inhibition of the complement system. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2007; 33:485-510. [DOI: 10.1134/s1068162007050020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
Recent research has yielded many interesting and potentially important therapeutic targets in sepsis. Specifically, the effects of antagonistic anti-cytokine therapies (tumor necrosis factor-alpha [TNF-alpha], interleukin-1 [IL-1]) and anti-endotoxin strategies utilizing antibodies against endotoxin or endotoxin receptor/carrier molecules (anti-CD14 or anti-LPS-binding protein) have been studied. Unfortunately, these approaches often failed clinically, and in many cases, the efficacy of these treatments was dependent on the severity of sepsis. Recently, clinical trials using insulin to lock blood glucose levels and activated protein C treatment have showed that while they provided some survival benefit, their efficacy does not appear to be predicated solely upon anti-inflammatory effects. Here, we will review work done in animal models of polymicrobial sepsis and clinical findings that support the hypothesis that apoptosis in the immune system is a pathologic event in sepsis that can be a therapeutic target. In this respect, experimental studies looking at the septic animal suggest that loss of lymphocytes during sepsis may be due to dysregulated apoptosis and that this appears to be brought on by a variety of mediators effecting 'intrinsic' as well as 'extrinsic' cell death pathways. From a therapeutic perspective this has provided a number of novel targets for clinically successful current, as well as future therapies, such as caspases (caspase inhibition/protease inhibition), pro-apoptotic protein-expression (via administration and/or over-expression of Bcl-2) and the death receptor family Fas-FasL (via. FasFP [fas fusion protein] and the application of siRNA against a number pro-apoptotic factors).
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Affiliation(s)
- Doreen E Wesche-Soldato
- Div. Surg. Res./Dept. Surgery, RI Hospital/Brown University Sch. Med., Providence, RI 02903, USA
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26
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Rozanov DV, Savinov AY, Golubkov VS, Tomlinson S, Strongin AY. Interference with the complement system by tumor cell membrane type-1 matrix metalloproteinase plays a significant role in promoting metastasis in mice. Cancer Res 2006; 66:6258-63. [PMID: 16778201 DOI: 10.1158/0008-5472.can-06-0539] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Neoplasms have developed strategies to protect themselves against the complement-mediated host immunity. Invasion- and metastasis-promoting membrane type-1 (MT1) matrix metalloproteinase (MMP) is strongly associated with many metastatic cancer types. The relative importance of the individual functions of MT1-MMP in metastasis was, however, unknown. We have now determined that the expression of murine MT1-MMP in murine melanoma B16F1 cells strongly increased the number of metastatic loci in the lungs of syngeneic C57BL/6 mice. In contrast, MT1-MMP did not affect the number of metastatic loci in complement-deficient C57BL/6-C3-/- mice. Our results indicated, for the first time, that the anticomplement activity of MT1-MMP played a significant role in promoting metastasis in vivo and determined the relative importance of the anticomplement activity in the total metastatic effect of this multifunctional proteolytic enzyme. We believe that our results shed additional light on the functions of MT1-MMP in cancer and clearly make this protease a promising drug target in metastatic malignancies.
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MESH Headings
- Animals
- Complement C3/deficiency
- Complement C3/genetics
- Complement C3/immunology
- Complement Inactivator Proteins/genetics
- Complement Inactivator Proteins/immunology
- Complement Inactivator Proteins/metabolism
- Fibrosarcoma/enzymology
- Fibrosarcoma/genetics
- Fibrosarcoma/immunology
- Humans
- Lung Neoplasms/enzymology
- Lung Neoplasms/immunology
- Lung Neoplasms/secondary
- Mammary Neoplasms, Experimental/enzymology
- Mammary Neoplasms, Experimental/genetics
- Mammary Neoplasms, Experimental/immunology
- Mammary Neoplasms, Experimental/pathology
- Matrix Metalloproteinase 14
- Matrix Metalloproteinases/genetics
- Matrix Metalloproteinases/immunology
- Matrix Metalloproteinases/metabolism
- Matrix Metalloproteinases, Membrane-Associated
- Melanoma, Experimental/enzymology
- Melanoma, Experimental/genetics
- Melanoma, Experimental/immunology
- Melanoma, Experimental/secondary
- Mice
- Mice, Inbred C57BL
- Neoplasms, Experimental/enzymology
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/immunology
- Neoplasms, Experimental/pathology
- Transfection
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Affiliation(s)
- Dmitri V Rozanov
- Cell Adhesion and Extracellular Matrix Biology, Burnham Institute for Medical Research, La Jolla, California 92037, USA
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27
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de Agostino Biella C, Uecker M, Fernandes da Silva M, Barbosa JE, Silva CL, Crott LSP. Investigation of the role of complement and complement receptors in the modulation of B cell activation by a Paracoccidioides brasiliensis cell wall fraction. Clin Immunol 2006; 118:324-31. [PMID: 16343991 DOI: 10.1016/j.clim.2005.09.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2005] [Revised: 09/19/2005] [Accepted: 09/22/2005] [Indexed: 12/14/2022]
Abstract
F1 fraction from Paracoccidioides brasiliensis is a potent activator of the complement system. Considering that complement receptors CR1 and CR2 are involved in the regulation of B cell response, we evaluated the in vitro effect of the F1 in the activation of B lymphocytes, as well as the participation of complement receptors in this process. Murine splenocytes were cultured in order to evaluate the expression of CD40, CD45RB and CD69 on B lymphocyte, and IgG and IgM were quantified in the culture supernatant. F1 participated in the activation of B cells, showing a positive modulation effect on all markers analyzed. An increase in the production of IgG was detected in the supernatants when the opsonized F1 fraction was present. Complement receptor blockade with monoclonal antibodies led to a partial reduction in immunoglobulin secretion, suggesting that these receptors, especially CR2, play a role in modulating the function of B lymphocyte stimulated with the opsonized F1 fraction. These results may contribute for a better understanding of the B cell activation and differentiation processes in response to the F1 fraction from P. brasiliensis.
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Affiliation(s)
- Carla de Agostino Biella
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas-Faculdade de Ciências Farmacêuticas de Ribeirão Preto-Universidade de São Paulo, Avenida do Café, S/N, B. Monte Alegre, CEP 14040-903, Ribeirão Preto, São Paulo, Brazil
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28
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Cramer DE, Allendorf DJ, Baran JT, Hansen R, Marroquin J, Li B, Ratajczak J, Ratajczak MZ, Yan J. Beta-glucan enhances complement-mediated hematopoietic recovery after bone marrow injury. Blood 2005; 107:835-40. [PMID: 16179370 PMCID: PMC1895628 DOI: 10.1182/blood-2005-07-2705] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Myelotoxic injury in the bone marrow (BM) as a consequence of total body irradiation (TBI) or granulocyte colony-stimulating factor (G-CSF) mobilization results in the deposition of iC3b on BM stroma (stroma-iC3b). In the present study, we have examined how stroma-iC3b interacts with hematopoietic progenitor cells (HPCs) and the role of complement (C) and complement receptor 3 (CR3) in BM injury/repair. We demonstrate here that stroma-iC3b tethers HPCs via the inserted (I) domain of HPC complement receptor 3 (CR3, CD11b/CD18, Mac-1). Following irradiation, stroma-iC3b was observed in the presence of purified IgM and normal mouse serum (NMS), but not serum from Rag-2(-/-) mice, implicating a role for antibody (Ab) and the classic pathway of C activation. Furthermore, a novel role for soluble yeast beta-glucan, a ligand for the CR3 lectin-like domain (LLD), in the priming of CR3(+) HPC is suggested. Soluble yeast beta-glucan could enhance the proliferation of tethered HPCs, promote leukocyte recovery following sublethal irradiation, and increase the survival of lethally irradiated animals following allogeneic HPC transplantation in a CR3-dependent manner. Taken together, these observations suggest a novel role for C, CR3, and beta-glucan in the restoration of hematopoiesis following injury.
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Affiliation(s)
- Daniel E Cramer
- Tumor Immunobiology Program, James Graham Brown Cancer Center, University of Louisville, 580 South Preston St, Louisville, KY 40202, USA
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29
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Hannan JP, Young KA, Guthridge JM, Asokan R, Szakonyi G, Chen XS, Holers VM. Mutational analysis of the complement receptor type 2 (CR2/CD21)-C3d interaction reveals a putative charged SCR1 binding site for C3d. J Mol Biol 2005; 346:845-58. [PMID: 15713467 DOI: 10.1016/j.jmb.2004.12.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2004] [Revised: 12/02/2004] [Accepted: 12/03/2004] [Indexed: 11/23/2022]
Abstract
We have characterized the interaction between the first two short consensus repeats (SCR1-2) of complement receptor type 2 (CR2, CD21) and C3d in solution, by utilising the available crystal structures of free and C3d-bound forms of CR2 to create a series of informative mutations targeting specific areas of the CR2-C3d complex. Wild-type and mutant forms of CR2 were expressed on the surface of K562 erythroleukemia cells and their binding ability assessed using C3dg-biotin tetramers complexed to fluorochrome conjugated streptavidin and measured by flow cytometry. Mutations directed at the SCR2-C3d interface (R83A, R83E, G84Y) were found to strongly disrupt C3dg binding, supporting the conclusion that the SCR2 interface reflected in the crystal structure is correct. Previous epitope and peptide mapping studies have also indicated that the PILN11GR13IS sequence of the first inter-cysteine region of SCR1 is essential for the binding of iC3b. Mutations targeting residues within or in close spatial proximity to this area (N11A, N11E, R13A, R13E, Y16A, S32A, S32E), and a number of other positively charged residues located primarily on a contiguous face of SCR1 (R28A, R28E, R36A, R36E, K41A, K41E, K50A, K50E, K57A, K57E, K67A, K67E), have allowed us to reassess those regions on SCR1 that are essential for CR2-C3d binding. The nature of this interaction and the possibility of a direct SCR1-C3d association are discussed extensively. Finally, a D52N mutant was constructed introducing an N-glycosylation sequence at an area central to the CR2 dimer interface. This mutation was designed to disrupt the CR2-C3d interaction, either directly through steric inhibition, or indirectly through disruption of a physiological dimer. However, no difference in C3dg binding relative to wild-type CR2 could be observed for this mutant, suggesting that the dimer may only be found in the crystal form of CR2.
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Affiliation(s)
- Jonathan P Hannan
- Department of Medicine and Immunology, University of Colorado Health Sciences Center, 4200 East Ninth Ave., Denver, CO 80262, USA
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30
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Analysis of Serum proteom before and after Intravenous Injection of wild ginseng herbal acupuncture. J Pharmacopuncture 2004. [DOI: 10.3831/kpi.2004.7.3.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Abstract
In man and in mouse, B-cell maturation occurs in steps, first in the bone marrow from hematopoietic precursors to immature/transitional B cells, then in the periphery from transitional to fully mature B cells. Each developmental step is tightly controlled by the expression and function of the B-cell receptor (BCR) and by the ability to interact with the microenvironment. Mature B cells collaborate with T cells in the adaptive immune response, leading to the production of high-affinity antibodies. This response is very accurate, but slow. Immediately after pathogen entry, however, antibodies already present in the serum reinforce the innate immune response and contribute to the first-line defense against infection. Low-affinity natural antibodies are produced by B-1a B cells in the mouse and immunoglobulin M (IgM) memory cells in man. These antibodies represent an immediate protection against all microorganisms and the only one against encapsulated bacteria. B-1a and IgM memory B cells may function as a link between the innate and adaptive immune response and thus perform a primordial B-cell function.
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32
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Morikis D, Lambris JD. The electrostatic nature of C3d-complement receptor 2 association. THE JOURNAL OF IMMUNOLOGY 2004; 172:7537-47. [PMID: 15187133 DOI: 10.4049/jimmunol.172.12.7537] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The association of complement component C3d with B or T cell complement receptor 2 (CR2 or CD21) is a link between innate and adaptive immunity. It has been recognized in experimental studies that the C3d-CR2 association is pH- and ionic strength-dependent. This led us to perform electrostatic calculations to obtain a theoretical understanding of the mechanism of C3d-CR2 association. We used the crystallographic structures of human free C3d, free CR2 (short consensus repeat (SCR)1-2), and the C3d-CR2(SCR1-2) complex, and continuum solvent representation, to obtain a detailed atomic-level picture of the components of the two molecules that contribute to association. Based on the calculation of electrostatic potentials for the free and bound species and apparent pK(a) values for each ionizable residue, we show that C3d-CR2(SCR1-2) recognition is electrostatic in nature and involves not only the association interface, but also the whole molecules. Our results are in qualitative agreement with experimental data that measured the ionic strength and pH dependence of C3d-CR2 association. Also, our results for the native molecules and a number of theoretical mutants of C3d explain experimental mutagenesis studies of amino acid replacements away from the association interface that modulate binding of iC3b with full-length CR2. Finally, we discuss the packing of the two SCR domains. Overall, our data provide global and site-specific explanations of the physical causes that underlie the ionic strength dependence of C3d-CR2 association in a unified model that accounts for all experimental data, some of which were previously thought to be contradictory.
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Affiliation(s)
- Dimitrios Morikis
- Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA.
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33
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Rozanov DV, Savinov AY, Golubkov VS, Postnova TI, Remacle A, Tomlinson S, Strongin AY. Cellular membrane type-1 matrix metalloproteinase (MT1-MMP) cleaves C3b, an essential component of the complement system. J Biol Chem 2004; 279:46551-7. [PMID: 15381670 DOI: 10.1074/jbc.m405284200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Neoplasms have developed numerous strategies to protect themselves against the host immune system. Membrane type-1 matrix metalloproteinase (MT1-MMP) is strongly associated with many cancer types and is up-regulated in the aggressive, metastatic neoplasms. During the past few years, there has been an increasing appreciation of the important, albeit incompletely understood, role of MT1-MMP in cancer. We have discovered, using cell-free and cell-based assays in vitro, that MT1-MMP proteolysis specifically targets C3b, an essential component of the complement propagation pathway. MT1-MMP proteolysis liberates the deposited C3 activation fragments from the cell surface. The shedding of these cell-deposited opsonins by MT1-MMP inhibits the complement cascade and protects breast carcinoma MCF7 cells from direct complement-mediated injury in the in vitro tests. The functional link associating MT1-MMP with the host immune system, heretofore unrecognized, may empower tumors with an escape mechanism that contributes to the protection against the host anti-tumor immunity as well as to the survival of invading and metastatic malignant cells in the bloodstream.
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Yin D, Zeng H, Ma L, Shen J, Xu H, Byrne GW, Chong AS. Cutting Edge: NK Cells Mediate IgG1-Dependent Hyperacute Rejection of Xenografts. THE JOURNAL OF IMMUNOLOGY 2004; 172:7235-8. [PMID: 15187097 DOI: 10.4049/jimmunol.172.12.7235] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Classic hyperacute rejection is dependent on the activation of the terminal components of complement. Recently, xenoantibodies with limited abilities to activate the classical pathway of complement in vitro have been implicated in the acute vascular rejection of xenografts. It is unclear how these Abs affect their pathogenic activities in vivo. In this study, we demonstrate the ability of an anti-Gal-alpha1,3Gal (Gal) IgG1, with modest complement-activating abilities in vitro, to induce xenograft rejection. This rejection was dependent on the activation of complement, on FcgammaR-mediated interactions, and on the presence of NK cells. Inhibition of any one of these factors resulted in the abrogation of IgG1-mediated rejection. In contrast, an anti-Gal IgG3 mAb induced classic, hyperacute rejection that was solely dependent on complement activation. Our observations implicate two types of IgG-mediated rejection; one that is dependent on complement activation, and a second that is uniquely dependent on complement, FcgammaR, and NK cells.
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Affiliation(s)
- Dengping Yin
- Section of Transplantation, Department of Surgery, The University of Chicago, 5841 South Maryland Avenue, Chicago, IL 60637, USA
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35
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Blandin S, Shiao SH, Moita LF, Janse CJ, Waters AP, Kafatos FC, Levashina EA. Complement-Like Protein TEP1 Is a Determinant of Vectorial Capacity in the Malaria Vector Anopheles gambiae. Cell 2004; 116:661-70. [PMID: 15006349 DOI: 10.1016/s0092-8674(04)00173-4] [Citation(s) in RCA: 456] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2003] [Revised: 12/17/2003] [Accepted: 01/14/2004] [Indexed: 11/26/2022]
Abstract
Anopheles mosquitoes are major vectors of human malaria in Africa. Large variation exists in the ability of mosquitoes to serve as vectors and to transmit malaria parasites, but the molecular mechanisms that determine vectorial capacity remain poorly understood. We report that the hemocyte-specific complement-like protein TEP1 from the mosquito Anopheles gambiae binds to and mediates killing of midgut stages of the rodent malaria parasite Plasmodium berghei. The dsRNA knockdown of TEP1 in adults completely abolishes melanotic refractoriness in a genetically selected refractory strain. Moreover, in susceptible mosquitoes this knockdown increases the number of developing parasites. Our results suggest that the TEP1-dependent parasite killing is followed by a TEP1-independent clearance of dead parasites by lysis and/or melanization. Further elucidation of the molecular mechanisms of TEP1-mediated parasite killing will be of great importance for our understanding of the principles of vectorial capacity in insects.
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Affiliation(s)
- Stephanie Blandin
- European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
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36
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Molnár E, Prechl J, Isaák A, Erdei A. Targeting with scFv: immune modulation by complement receptor specific constructs. J Mol Recognit 2003; 16:318-23. [PMID: 14523944 DOI: 10.1002/jmr.642] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The fate of a microbe in the host is determined by various molecules of the innate immune system, which recognize the microbe and enhance its interaction with antigen presenting cells. This 'natural targeting' phenomenon, however, does not function when antigens with limited immunogenicity enter the host. Peptide vaccines, for instance, require adjuvants to induce immune responses. As a surrogate for the natural targeting mechanisms, antibodies against selected receptors of antigen presenting cells, conjugated with the peptides, could be used as targeting devices. Here we review various antibody-mediated antigen-targeting strategies, paying special attention to complement receptor-mediated targeting. We also describe and summarize our method of single-chain antibody-mediated targeting of viral epitopes to complement receptor type two and discuss the perspectives of single-chain antibody-mediated antigen targeting.
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Affiliation(s)
- Eszter Molnár
- Department of Immunology, L Eötvös University, Budapest, Hungary
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Gadjeva M, Verschoor A, Brockman MA, Jezak H, Shen LM, Knipe DM, Carroll MC. Macrophage-derived complement component C4 can restore humoral immunity in C4-deficient mice. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:5489-95. [PMID: 12421924 DOI: 10.4049/jimmunol.169.10.5489] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Mice with a disrupted C4 locus (C4(-/-)) have an impaired immune response to thymus-dependent Ags. To test the role of bone marrow-derived C4 in humoral immunity, we reconstituted deficient animals with wild-type bone marrow or an enriched fraction of bone marrow-derived macrophages. C4 chimeras were immunized with 4-hydroxy-3-nitrophenyl(5) conjugated to keyhole limpet hemocyanin (NP(5)- KLH) or infected with HSV-1, and the Ab response was evaluated. Wild-type bone marrow rescued the humoral immune response to both Ags, i.e., the soluble Ag and HSV-1, demonstrating that local C4 production is sufficient for humoral responses. Although the C4 chimeric animals lacked detectable C4 in their sera, C4 mRNA was identified in splenic sections by in situ hybridization, and C4 protein deposits were identified in the germinal center areas of splenic follicles by immunofluorescence staining. Macrophages derived from bone marrow produced sufficient C4 protein to restore the humoral response to NP(5)-KLH in C4-deficient animals when administered along with Ag. Cell-sorting experiments, followed by C4-specific RT-PCR, identified splenic macrophages (CD11b(+), CD11c(-)) as a cellular source for C4 synthesis within the spleen.
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Affiliation(s)
- Mihaela Gadjeva
- Center for Blood Research, 221 Longwood Avenue, Boston, MA 02115, USA
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38
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Kapadia SB, Levine B, Speck SH, Virgin HW. Critical role of complement and viral evasion of complement in acute, persistent, and latent gamma-herpesvirus infection. Immunity 2002; 17:143-55. [PMID: 12196286 DOI: 10.1016/s1074-7613(02)00369-2] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Several gamma-herpesviruses encode homologs of host regulators of complement activation (RCA) proteins, suggesting that they have evolved immune evasion strategies targeting complement. We evaluated the role of complement factor C3 (C3) and the murine gamma-herpesvirus 68 (gammaHV68) RCA protein in viral pathogenesis. Deletion of the gammaHV68 RCA protein decreased virulence during acute CNS infection, and this attenuation was specifically reversed by deletion of host C3. The gammaHV68 RCA protein was also important for persistent viral replication and virulence in IFNgammaR(-/-) mice. In addition, C3 played a role in regulating latency, but this was not counteracted by the gammaHV68 RCA protein. We conclude that complement is a key host defense against gamma-herpesvirus infection and that gamma-herpesviruses have evolved an immune evasion strategy that is effective against complement-mediated antiviral responses during acute but not latent infection.
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Affiliation(s)
- Sharookh B Kapadia
- Department of Immunology and Pathology, Department of Molecular Microbiology, Washington University School of Medicine, Box 8118, 660 South Euclid Avenue, St. Louis, MO 63110, USA
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Józsi M, Prechl J, Bajtay Z, Erdei A. Complement receptor type 1 (CD35) mediates inhibitory signals in human B lymphocytes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:2782-8. [PMID: 11884446 DOI: 10.4049/jimmunol.168.6.2782] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The complement system---particularly component C3---has been demonstrated to be a key link between innate and adaptive immunity. The trimolecular complex of complement receptor type 2 (CR2), CD19, and CD81 is known to promote B cell activation when coligated with the B cell Ag receptor. In the present study, we aimed to elucidate the role of human complement receptor type 1 (CR1), the other C3-receptor on B cells. As ligand, aggregated C3 and aggregated C3(H(2)O), i.e., multimeric "C3b-like C3", are used, which bind to CR1, but not to CR2. In experiments studying the functional consequences of CR1-clustering, the multimeric ligand is shown to inhibit the proliferation of tonsil B cells activated with a suboptimal dose of anti-IgM F(ab')(2). Importantly, this inhibitory activity also occurs in the presence of the costimulatory cytokines IL-2 and IL-15. The anti-IgM-induced transient increase in the concentration of intracellular free Ca(2+) and phosphorylation of several cytoplasmic proteins are strongly reduced in the presence of the CR1 ligand. Data presented indicate that CR1 has a negative regulatory role in the B cell Ag receptor mediated activation of human B lymphocytes.
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Affiliation(s)
- Mihály Józsi
- Department of Immunology and Research Group of the Hungarian Academy of Sciences, Eötvös Loránd University, Budapest, Hungary
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40
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Prechl J, Baiu DC, Horváth A, Erdei A. Modeling the presentation of C3d-coated antigen by B lymphocytes: enhancement by CR1/2-BCR co-ligation is selective for the co-ligating antigen. Int Immunol 2002; 14:241-7. [PMID: 11867560 DOI: 10.1093/intimm/14.3.241] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have used a set of single-chain variable fragment antibodies (sc) genetically fused with an influenza hemagglutinin-derived peptide as a means to investigate the role of CR1 and CR2 in antigen presentation by B cells. When incubated with the B cell lymphoma 2PK3, peptide-containing sc specific for either CR1 or CR1/2 mediated activation of the hemagglutinin peptide-specific T cell line IP-12-7, as assessed by IL-2 production. Efficient presentation was dependent on the binding of the constructs to CR1/2, implying that receptor-mediated endocytosis is responsible for the effect. Cross-linkage of CR1/2 or CD19 by mAb did not increase the extent of T cell activation. However, when CR1/2 was co-ligated with the BCR--using either polyclonal goat anti-mouse IgG or recombinant protein LA--the antigen concentration required to activate T cells decreased by two orders of magnitude. Moreover, this enhancement was selective for the antigen included in these complexes and did not affect the presentation of a free peptide or of antigen bound to CR1/2 excluded from the complexes. These results suggest that B cells may bind various C3d-coated antigens at a time, but only the one which reacts with the BCR will be processed with high efficiency. This mechanism may ensure the specificity of cognate T cell help.
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Affiliation(s)
- József Prechl
- Department of Immunology, Loránd Eötvös University, Pázmány Péter s. 1/C, Budapest, Hungary
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41
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Abstract
Phagocytosis of bacterial pathogens is at the heart of the pathogenesis of infections. Pathogens have evolved a large array of strategies to escape the deleterious effect of phagocytosis by professional phagocytes among which avoiding phagocytosis, killing the phagocytes or surviving inside them are the most 'popular' solutions. Bacterial pathogens are also using induction of phagocytic entry into non-professional phagocytic cells, such as epithelial cells, as a strategy of survival and multiplication. We have taken enteroinvasive micro-organisms such as Yersinia, Shigella and Salmonella as a paradigm of the significance of phagocytosis/antiphagocytosis in the development of an infection and on the elicitation of the host response.
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Affiliation(s)
- P Sansonetti
- Unité de Pathogénie Microbienne Moléculaire et Unité INSERM 389, Institut Pasteur, 28 Rue du Docteur Roux, 75724 Paris Cedex 15, France.
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42
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Suradhat S, Braun RP, Lewis PJ, Babiuk LA, van Drunen Littel-van den Hurk S, Griebel PJ, Baca-Estrada ME. Fusion of C3d molecule with bovine rotavirus VP7 or bovine herpesvirus type 1 glycoprotein D inhibits immune responses following DNA immunization. Vet Immunol Immunopathol 2001; 83:79-92. [PMID: 11604163 DOI: 10.1016/s0165-2427(01)00369-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The binding of the complement C3d molecule with receptors on B cells and/or follicular dendritic cells (FDCs) influences the induction of humoral immune responses. For example, C3d fused to an antigen has been shown to have a strong adjuvant effect on antibody production. We investigated the possibility that co-expression of antigen and C3d as a fusion protein could enhance antigen-specific immune responses, following plasmid immunization. One or two copies of murine C3d-cDNA, C3d or (C3d)(2), respectively, were cloned together with bovine rotavirus (BRV) VP7 or bovine herpesvirus type 1 (BHV-1) glycoprotein D (gD) genes. All constructs contained a signal peptide that resulted in the secretion of the expressed proteins. In vitro, the characterization of the chimeric proteins indicated that both VP7 and gD retained their antigenicity and the C3d remained biologically active. However, immunization with plasmids encoding VP7-C3d chimeras did not enhance rotavirus-specific antibody responses and the frequency of BRV-specific IFN-gamma secreting cells in the spleens were significantly lower in mice immunized with pVP7-(C3d)(2) when compared with mice immunized with plasmid encoding VP7. The same pattern of immune responses was observed for plasmids encoding gD-C3d. Both gD-specific antibody responses and the frequency of gD-specific IFN-gamma secreting cells were significantly lower in mice immunized with plasmid expressing gD-C3d chimeras when compared with mice immunized with plasmid encoding gD alone. These results indicate that co-expression of C3d with an antigen actually inhibit both humoral and cell-mediated antigen-specific immune responses.
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Affiliation(s)
- S Suradhat
- Veterinary Infectious Disease Organization (VIDO), University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan, Canada S7N 5E3
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43
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De Silvestri A, Pasi A, Martinetti M, Belloni C, Tinelli C, Rondini G, Salvaneschi L, Cuccia M. Family study of non-responsiveness to hepatitis B vaccine confirms the importance of HLA class III C4A locus. Genes Immun 2001; 2:367-72. [PMID: 11704802 DOI: 10.1038/sj.gene.6363792] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2001] [Revised: 07/18/2001] [Accepted: 08/03/2001] [Indexed: 12/14/2022]
Abstract
Non-responsiveness to hepatitis B virus (HBV) vaccine in adults is strongly associated with HLA-C4AQ0,DRB1*0301,DQB1*02 haplotype. This association was also demonstrated in neonates who failed to mount a humoral response to challenge with HBV vaccine. About 4% of vaccinated newborns do not reach a protective antibody level (> or =10 mIU/ml) at seroconversion and 0.4% is a non-responder even after receiving a fourth dose of vaccine (true non-responders (TNR)); while 3.6% achieved an antibody level > or =10 mIU/ml (slow responders (SR)) only when reboostered with the fourth dose. In the present study we extend the vaccination and HLA typing to 91 family members of probands to understand better the possible parent-to-child transmission of this trait. A transmission disequilibrium test (TDT), performed in 27 families, showed that the C4AQ0 allele was almost always transmitted to probands, both TNRs and SRs. Although not statistically significant, the highest LOD score was obtained with C4A locus: 1.58. These results suggest the presence of a region regulating immune response against HBV vaccination near to or coincident with the C4A locus.
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Affiliation(s)
- A De Silvestri
- Unità di Biometria, Dipartimento di Genetica e Microbiologia-Università di Pavia, Via Abbiategrasso 207, Pavia, Italy.
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44
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Dragon-Durey MA, Quartier P, Frémeaux-Bacchi V, Blouin J, de Barace C, Prieur AM, Weiss L, Fridman WH. Molecular basis of a selective C1s deficiency associated with early onset multiple autoimmune diseases. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:7612-6. [PMID: 11390518 DOI: 10.4049/jimmunol.166.12.7612] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have investigated the molecular basis of selective and complete C1s deficiency in 2-year-old girl with complex autoimmune diseases including lupus-like syndrome, Hashimoto's thyroiditis, and autoimmune hepatitis. This patient's complement profile was characterized by the absence of CH50 activity, C1 functional activity <10%, and undetectable levels of C1s Ag associated with normal levels of C1r and C1q Ags. Exon-specific amplification of genomic DNA by PCR followed by direct sequence analysis revealed a homozygous nonsense mutation in the C1s gene exon XII at codon 534, caused by a nucleotide substitution from C (CGA for arginine) to T (TGA for stop codon). Both parents were heterozygous for this mutation. We used the new restriction site for endonuclease Fok-1 created by the mutation to detect this mutation in the genomic DNA of seven healthy family members. Four additional heterozygotes for the mutation were identified in two generations. Our data characterize for the first time the genetic defect of a selective and complete C1s deficiency in a Caucasian patient.
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Affiliation(s)
- M A Dragon-Durey
- Service d'Immunologie Biologique, Hôpital Européen Georges Pompidou, AP-HP, Paris, France.
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45
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Vereshchagina LA, Tolnay M, Tsokos GC. Multiple transcription factors regulate the inducible expression of the human complement receptor 2 promoter. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:6156-63. [PMID: 11342636 DOI: 10.4049/jimmunol.166.10.6156] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Complement receptor 2 (CR2) is regulated at the transcriptional level, but the promoter elements and the transcription factors that bind to them and contribute to its regulation are unknown. After documenting that PMA and cAMP induced the activity of the CR2 promoter by 10-fold, we conducted promoter truncation and mutagenesis experiments, in conjunction with shift assays, to determine the functionally important regions of the promoter and the proteins that bind to them. We identified two regions, separated by approximately 900 nucleotides, which together were responsible for inducible promoter activity. Mutagenesis of single promoter elements demonstrated a functional upstream stimulatory factor/E box in the TATA box-proximal region and three equally important, closely spaced, CREB/AP-1 half-sites in the upstream promoter region. The cAMP response element-binding protein (CREB)/AP-1 half-sites bound in vitro Jun and CREB that are induced by protein kinases A and/or C. The 900-nucleotide segment stretching between the above two regions had no functional impact on the induced transcription, and its deletion increased the promoter activity. Finally, a region upstream of the distal site had a repressor activity on CR2 transcription. Moreover, IL-4 induced binding of CREB and AP-1 to the upstream promoter elements and resulted in increased CR2 surface protein expression. These studies have characterized regions of the CR2 promoter and the transcription factors that bind to them and are crucial to induced CR2 expression. Our studies may provide insights to novel approaches to modulate B cell function by regulating CR2 gene transcription.
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MESH Headings
- 5' Untranslated Regions/drug effects
- 5' Untranslated Regions/immunology
- Antibodies, Monoclonal/pharmacology
- Base Sequence
- Binding Sites, Antibody/genetics
- Bucladesine/pharmacology
- CD40 Antigens/immunology
- Cell Line, Transformed
- Cell Membrane/immunology
- Cell Membrane/metabolism
- DNA-Binding Proteins/metabolism
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/immunology
- Genes, Reporter/drug effects
- Genes, Reporter/immunology
- Humans
- Interleukin-4/pharmacology
- Mutagenesis, Site-Directed
- Nuclear Proteins/metabolism
- Promoter Regions, Genetic/drug effects
- Promoter Regions, Genetic/immunology
- Receptors, Complement 3d/biosynthesis
- Receptors, Complement 3d/genetics
- Receptors, Complement 3d/physiology
- Regulatory Sequences, Nucleic Acid/immunology
- Sequence Deletion/immunology
- Tetradecanoylphorbol Acetate/pharmacology
- Transcription Factors/metabolism
- Transcription Factors/physiology
- Transfection
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Affiliation(s)
- L A Vereshchagina
- Department of Cellular Injury, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
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46
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Guthridge JM, Rakstang JK, Young KA, Hinshelwood J, Aslam M, Robertson A, Gipson MG, Sarrias MR, Moore WT, Meagher M, Karp D, Lambris JD, Perkins SJ, Holers VM. Structural Studies in Solution of the Recombinant N-Terminal Pair of Short Consensus/Complement Repeat Domains of Complement Receptor Type 2 (CR2/CD21) and Interactions with Its Ligand C3dg. Biochemistry 2001; 40:5931-41. [PMID: 11352728 DOI: 10.1021/bi0101749] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Human complement receptor type 2 (CR2, CD21) is a cell surface receptor that binds three distinct ligands (complement C3d, Epstein-Barr virus gp350/220, and the low-affinity IgE receptor CD23) via the N-terminal two of fifteen or sixteen short consensus/complement repeat (SCR) domains. Here, we report biophysical studies of the CR2 SCR 1-2 domain binding to its ligand C3dg. Two recombinant forms of CR2 containing the SCR 1-2 and SCR 1-15 domains were expressed in high yield in Pichia pastoris and baculovirus, respectively. Circular dichroism spectroscopy showed that CR2 SCR 1-2 receptor possessed a beta-sheet secondary structure with a melting temperature of 59 degrees C. Using surface plasmon resonance, kinetic parameters for the binding of either CR2 SCR 1-2 or the full-length SCR 1-15 form of CR2 showed that the affinity of binding to immobilized C3d is comparable for the SCR 1-15 compared to the SCR 1-2 form of CR2. Unexpectedly, both the association and dissociation rates for the SCR 1-15 form were slower than for the SCR 1-2 form. These data show that the SCR 1-2 domains account for the primary C3dg binding site of CR2 and that the additional SCR domains of full-length CR2 influence the ability of CR2 SCR 1-2 to interact with its ligand. Studies of the pH and ionic strength dependence of the interaction between SCR 1-2 and C3d by surface plasmon resonance showed that this is influenced by charged interactions, possibly involving the sole His residue in CR2 SCR 1-2. Sedimentation equilibrium studies of CR2 SCR 1-2 gave molecular weights of 17 000, in good agreement with its sequence-derived molecular weight to show that this was monomeric. Its sedimentation coefficient was determined to be 1.36 S. The complex with C3d gave molecular weights in 50 mM and 200 mM NaCl buffer that agreed closely with its sequence-derived molecular weight of 50 600 and showed that a 1:1 complex had been formed. Molecular graphics views of homology models for the separate CR2 SCR 1 and SCR 2 domains showed that both SCR domains exhibited a distribution of charged groups throughout its surface. The single His residue is located near a long eight-residue linker between the two SCR domains and may influence the linker conformation and the association of C3d and CR2 SCR 1-2 into their complex. Sedimentation modeling showed that the arrangement of the two SCR domains in CR2 SCR 1-2 is highly extended in solution.
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Affiliation(s)
- J M Guthridge
- Department of Medicine, Division of Rheumatology, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA
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47
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Berstad AE, Høgåsen K, Bukholm G, Moran AP, Brandtzaeg P. Complement activation directly induced by Helicobacter pylori. Gastroenterology 2001; 120:1108-16. [PMID: 11266375 DOI: 10.1053/gast.2001.23248] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
BACKGROUND AND AIMS Helicobacter pylori is a frequent gram-negative colonizer of the human stomach. Its interaction with complement may be involved in the pathogenesis of chronic gastritis, and was mechanistically studied in vitro. METHODS Four H. pylori strains, 2 cytotoxin-associated genes (cag)A+ and 2 cagA-, were isolated from infected patients. Bacteria or purified H. pylori lipopolysaccharides (LPSs) were incubated with nonimmune serum at 37 degrees C; the activation products C3b/iC3b/C3c (C3bc) and terminal complement complex (TCC) were then quantified by immunoassays. The serum sensitivity of 1 strain (L01, cagA+) was tested by counting the numbers of colony-forming units. RESULTS All strains and LPSs generated large amounts of C3bc and TCC. Blocking of the classic complement pathway by the calcium chelator ethylene glycol tetraacetic acid (EGTA) markedly reduced the complement products, suggesting that H. pylori and its LPSs directly engage the classic activation pathway. H. pylori was shown to be serum sensitive, but 30% or more nonimmune serum was necessary to induce marked killing. After 5 minutes, swelled bacteria coated with C3bc and TCC were shown. CONCLUSIONS H. pylori is complement sensitive and activates the classic pathway even in the absence of specific antibodies. Released cell wall constituents such as LPSs can activate complement and may explain why this bacterium induces gastric pathology without invading the mucosa.
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Affiliation(s)
- A E Berstad
- Laboratory for Immunohistochemistry and Immunopathology (LIIPAT), Rikshospitalet, Institute of Pathology, N-0027 Oslo, Norway.
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Martinetti M, De Silvestri A, Belloni C, Pasi A, Tinelli C, Pistorio A, Salvaneschi L, Rondini G, Avanzini MA, Cuccia M. Humoral response to recombinant hepatitis B virus vaccine at birth: role of HLA and beyond. Clin Immunol 2000; 97:234-40. [PMID: 11112362 DOI: 10.1006/clim.2000.4933] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
From 1991 to 1998 we vaccinated 4835 neonates against hepatitis B virus (HBV) and monitored their humoral response to the recombinant vaccine. In a sample of 184 of these babies we studied the association between HLA class I and II genomic polymorphisms and humoral response to the vaccine and the association between the response and immune-mediated diseases. A subgroup of 96 babies also underwent HLA class III (C4A and C4B) typing. Four levels of humoral response were identified, each with a peculiar MHC restriction. Different HLA products seem to act as agonists (C4AQ0 and HLA-DQB1(*)02) or antagonists (C4AQ0, HLA-DQB1(*)02, and HLA-DRB1(*)11, DQB1(*)0301) in lowering humoral response to HBV vaccine. The group of responders was characterized more for lacking "nonresponder" alleles than for having specific "responder" ones. Tolerance to HBV peptides may have clinical implications, possibly being a marker for babies with a genetic risk of immunopathologies. In fact, many of the poor responders carried from two to four HLA-DQ alpha beta heterodimers predisposing to insulin-dependent diabetes mellitus and celiac disease. Two true nonresponders suffered from allergies and two slow responders had transient episodes of hyperglycemia.
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Affiliation(s)
- M Martinetti
- Servizio di Immunoematologia, Transfusione e Centro di Immunologia dei Trapianti, IRCCS Policlinico S. Matteo, Pavia, Italy
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49
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Guo RF, Huber-Lang M, Wang X, Sarma V, Padgaonkar VA, Craig RA, Riedemann NC, McClintock SD, Hlaing T, Shi MM, Ward PA. Protective effects of anti-C5a in sepsis-induced thymocyte apoptosis. J Clin Invest 2000; 106:1271-80. [PMID: 11086028 PMCID: PMC381438 DOI: 10.1172/jci10793] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Multiorgan apoptosis occurs during sepsis. Following cecal ligation and puncture (CLP) in rats, thymocytes underwent apoptosis in a time-dependent manner. C5a blockade dramatically reduced thymocyte apoptosis as measured by thymic weight, binding of annexin V to thymocytes, and laddering of thymocyte DNA. When C5a was generated in vivo by infusion of purified cobra venom factor (CVF), thymocyte apoptosis was significantly increased. Similar results were found when CVF was injected in vivo during the early stages of CLP. In animals 12 hours after induction of CLP, there was an increase in the activities of caspase-3, -6, and -9, but not caspase-1 and -8. Cytosolic cytochrome c levels increased by twofold, whereas mitochondrial levels showed a 50% decrease. Western blot analysis revealed that the content of Bcl-X(L) (but not of Bcl-2, BAX, Bad, and Bim) significantly decreased in thymocytes after CLP. C5a blockade in the sepsis model almost completely inhibited caspase-3, -6, and -9 activation, significantly preserved cytochrome c in the mitochondrial fraction, and restored Bcl-X(L) expression. These data suggest that systemic activation of complement induces C5a-dependent apoptosis of thymocytes and that the blockade of C5a during sepsis rescues thymocytes from apoptosis.
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Affiliation(s)
- R F Guo
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan 48109-0602, USA
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50
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Friedman HM, Wang L, Pangburn MK, Lambris JD, Lubinski J. Novel mechanism of antibody-independent complement neutralization of herpes simplex virus type 1. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 165:4528-36. [PMID: 11035093 DOI: 10.4049/jimmunol.165.8.4528] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The envelope surface glycoprotein C (gC) of HSV-1 interferes with the complement cascade by binding C3 and activation products C3b, iC3b, and C3c, and by blocking the interaction of C5 and properdin with C3b. Wild-type HSV-1 is resistant to Ab-independent complement neutralization; however, HSV-1 mutant virus lacking gC is highly susceptible to complement resulting in > or =100-fold reduction in virus titer. We evaluated the mechanisms by which complement inhibits HSV-1 gC null virus to better understand how gC protects against complement-mediated neutralization. C8-depleted serum prepared from an HSV-1 and -2 Ab-negative donor neutralized gC null virus comparable to complement-intact serum, indicating that C8 and terminal lytic activity are not required. In contrast, C5-depleted serum from the same donor failed to neutralize gC null virus, supporting a requirement for C5. EDTA-treated serum did not neutralize gC null virus, indicating that complement activation is required. Factor D-depleted and C6-depleted sera neutralized virus, suggesting that the alternative complement pathway and complement components beyond C5 are not required. Complement did not aggregate virus or block attachment to cells. However, complement inhibited infection before early viral gene expression, indicating that complement affects one or more of the following steps in virus replication: virus entry, uncoating, DNA transport to the nucleus, or immediate early gene expression. Therefore, in the absence of gC, HSV-1 is readily inhibited by complement by a C5-dependent mechanism that does not require viral lysis, aggregation, or blocking virus attachment.
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MESH Headings
- Adult
- Animals
- Antibodies, Viral/blood
- Antibodies, Viral/physiology
- Chlorocebus aethiops
- Complement C5/physiology
- Complement C8/physiology
- Complement Pathway, Alternative/immunology
- Disaccharides/immunology
- Gene Expression Regulation, Viral/immunology
- Genes, Immediate-Early/immunology
- HeLa Cells/immunology
- HeLa Cells/metabolism
- HeLa Cells/virology
- Herpes Simplex/genetics
- Herpes Simplex/immunology
- Herpesvirus 1, Human/genetics
- Herpesvirus 1, Human/immunology
- Herpesvirus 1, Human/physiology
- Herpesvirus 1, Human/ultrastructure
- Humans
- Neutralization Tests
- Receptors, Virus/antagonists & inhibitors
- Receptors, Virus/immunology
- Vero Cells/immunology
- Vero Cells/metabolism
- Vero Cells/virology
- Viral Envelope Proteins/deficiency
- Viral Envelope Proteins/genetics
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Affiliation(s)
- H M Friedman
- Department of Medicine, Infectious Diseases Division and Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
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