1
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Ma Y, Jiang T, Zhu X, Xu Y, Wan K, Zhang T, Xie M. Efferocytosis in dendritic cells: an overlooked immunoregulatory process. Front Immunol 2024; 15:1415573. [PMID: 38835772 PMCID: PMC11148234 DOI: 10.3389/fimmu.2024.1415573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 05/09/2024] [Indexed: 06/06/2024] Open
Abstract
Efferocytosis, the process of engulfing and removing apoptotic cells, plays an essential role in preserving tissue health and averting undue inflammation. While macrophages are primarily known for this task, dendritic cells (DCs) also play a significant role. This review delves into the unique contributions of various DC subsets to efferocytosis, highlighting the distinctions in how DCs and macrophages recognize and handle apoptotic cells. It further explores how efferocytosis influences DC maturation, thereby affecting immune tolerance. This underscores the pivotal role of DCs in orchestrating immune responses and sustaining immune equilibrium, providing new insights into their function in immune regulation.
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Affiliation(s)
- Yanyan Ma
- Department of Emergency and Critical Care Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Tangxing Jiang
- Department of Emergency Medicine, Qilu Hospital of Shandong University, Jinan, China
| | - Xun Zhu
- Department of Emergency and Critical Care Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Yizhou Xu
- Department of Emergency and Critical Care Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Ke Wan
- Department of Emergency and Critical Care Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Tingxuan Zhang
- Department of Emergency and Critical Care Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Miaorong Xie
- Department of Emergency and Critical Care Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
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2
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Klaus T, Hieber C, Bros M, Grabbe S. Integrins in Health and Disease-Suitable Targets for Treatment? Cells 2024; 13:212. [PMID: 38334604 PMCID: PMC10854705 DOI: 10.3390/cells13030212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 01/13/2024] [Accepted: 01/22/2024] [Indexed: 02/10/2024] Open
Abstract
Integrin receptors are heterodimeric surface receptors that play multiple roles regarding cell-cell communication, signaling, and migration. The four members of the β2 integrin subfamily are composed of an alternative α (CD11a-d) subunit, which determines the specific receptor properties, and a constant β (CD18) subunit. This review aims to present insight into the multiple immunological roles of integrin receptors, with a focus on β2 integrins that are specifically expressed by leukocytes. The pathophysiological role of β2 integrins is confirmed by the drastic phenotype of patients suffering from leukocyte adhesion deficiencies, most often resulting in severe recurrent infections and, at the same time, a predisposition for autoimmune diseases. So far, studies on the role of β2 integrins in vivo employed mice with a constitutive knockout of all β2 integrins or either family member, respectively, which complicated the differentiation between the direct and indirect effects of β2 integrin deficiency for distinct cell types. The recent generation and characterization of transgenic mice with a cell-type-specific knockdown of β2 integrins by our group has enabled the dissection of cell-specific roles of β2 integrins. Further, integrin receptors have been recognized as target receptors for the treatment of inflammatory diseases as well as tumor therapy. However, whereas both agonistic and antagonistic agents yielded beneficial effects in animal models, the success of clinical trials was limited in most cases and was associated with unwanted side effects. This unfavorable outcome is most probably related to the systemic effects of the used compounds on all leukocytes, thereby emphasizing the need to develop formulations that target distinct types of leukocytes to modulate β2 integrin activity for therapeutic applications.
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Affiliation(s)
| | | | | | - Stephan Grabbe
- Department of Dermatology, University Medical Center of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131 Mainz, Germany; (T.K.); (C.H.); (M.B.)
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3
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Kareem S, Jacob A, Mathew J, Quigg RJ, Alexander JJ. Complement: Functions, location and implications. Immunology 2023; 170:180-192. [PMID: 37222083 PMCID: PMC10524990 DOI: 10.1111/imm.13663] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 05/09/2023] [Indexed: 05/25/2023] Open
Abstract
The complement system, an arm of the innate immune system plays a critical role in both health and disease. The complement system is highly complex with dual possibilities, helping or hurting the host, depending on the location and local microenvironment. The traditionally known functions of complement include surveillance, pathogen recognition, immune complex trafficking, processing and pathogen elimination. The noncanonical functions of the complement system include their roles in development, differentiation, local homeostasis and other cellular functions. Complement proteins are present in both, the plasma and on the membranes. Complement activation occurs both extra- and intracellularly, which leads to considerable pleiotropy in their activity. In order to design more desirable and effective therapies, it is important to understand the different functions of complement, and its location-based and tissue-specific responses. This manuscript will provide a brief overview into the complex nature of the complement cascade, outlining some of their complement-independent functions, their effects at different locale, and their implication in disease settings.
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Affiliation(s)
- Samer Kareem
- Department of Medicine, University at Buffalo, Buffalo, New York, United States
| | - Alexander Jacob
- Department of Medicine, University at Buffalo, Buffalo, New York, United States
| | - John Mathew
- Department of Rheumatology, Christian Medical College, Vellore, India
| | - Richard J Quigg
- Department of Medicine, University at Buffalo, Buffalo, New York, United States
| | - Jessy J Alexander
- Department of Medicine, University at Buffalo, Buffalo, New York, United States
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4
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The Complement System, Aging, and Aging-Related Diseases. Int J Mol Sci 2022; 23:ijms23158689. [PMID: 35955822 PMCID: PMC9369321 DOI: 10.3390/ijms23158689] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/03/2022] [Accepted: 08/03/2022] [Indexed: 12/10/2022] Open
Abstract
The complement system is a part of the immune system and consists of multiple complement components with biological functions such as defense against pathogens and immunomodulation. The complement system has three activation pathways: the classical pathway, the lectin pathway, and the alternative pathway. Increasing evidence indicates that the complement system plays a role in aging. Complement plays a role in inflammatory processes, metabolism, apoptosis, mitochondrial function, and Wnt signaling pathways. In addition, the complement system plays a significant role in aging-related diseases, including Alzheimer’s disease, age-related macular degeneration, and osteoarthritis. However, the effect of complement on aging and aging-related diseases is still unclear. Thus, a better understanding of the potential relationship between complement, aging, and aging-related diseases will provide molecular targets for treating aging, while focusing on the balance of complement in during treatment. Inhibition of a single component does not result in a good outcome. In this review, we discussed the research progress and effects of complement in aging and aging-related diseases.
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5
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Abstract
Macrophages have emerged at the forefront of research in immunology and transplantation because of recent advances in basic science. New findings have illuminated macrophage populations not identified previously, expanded upon traditional macrophage phenotypes, and overhauled macrophage ontogeny. These advances have major implications for the field of transplant immunology. Macrophages are known to prime adaptive immune responses, perpetuate T-cell-mediated rejection and antibody-mediated rejection, and promote allograft fibrosis. In this review, macrophage phenotypes and their role in allograft injury of solid organ transplants will be discussed with an emphasis on kidney transplantation. Additionally, consideration will be given to the prospect of manipulating macrophage phenotypes as cell-based therapy. Innate immunity and macrophages represent important players in allograft injury and a promising target to improve transplant outcomes.
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Affiliation(s)
- Sarah E. Panzer
- Department of Medicine, Division of Nephrology, University of Wisconsin, Madison, WI, United States
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6
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Ghate A, Sharma S, Agrawal P, Sahu A. Differential expression of complement receptors CR1/2 and CR4 by murine M1 and M2 macrophages. Mol Immunol 2021; 137:75-83. [PMID: 34229135 DOI: 10.1016/j.molimm.2021.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Revised: 05/20/2021] [Accepted: 06/06/2021] [Indexed: 11/26/2022]
Abstract
Macrophages polarize into functionally divergent phenotypes - M1 and M2 - which express distinct receptors. These cells are known to express complement receptors, including CR1, CR3, and CR4. However, whether these complement receptors are differentially expressed on M1 and M2 macrophages is not yet known. Herein, we have examined the expression of CR1 to CR4 on murine bone marrow-derived M1 (stimulated with IFN-γ or LPS) and M2 (stimulated with IL-4 or IL-4 + IL-13) macrophages. We show that M1 cells exhibit increased expression of CR1/2, whereas M2 cells display the higher expression of CR4; CR3 is equally expressed on both the phenotypes. Thus, M1 cells are CR1/2+CR4+, and M2 are CR1/2-CR4+. Functional probing of these cells for their phagocytic ability indicates that M1 cells, which express higher CR1/2, internalize a significantly greater number of C3b-opsonized erythrocytes. Both M1 and M2 cells, on the other hand, internalize iC3b-opsonized erythrocytes to a similar extent. Interestingly, the phagocytic receptor involved in phagocytosis of iC3b-opsonized erythrocytes is only CR3 with no contribution of CR4. We, thus, propose that complement receptor expression can be used in combination with the expression of other known polarization markers to better locate a macrophage along its phenotypic spectrum.
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Affiliation(s)
- Arya Ghate
- Complement Biology Laboratory, National Centre for Cell Science, S. P. Pune University Campus, Pune - 411007, India
| | - Samriddhi Sharma
- Complement Biology Laboratory, National Centre for Cell Science, S. P. Pune University Campus, Pune - 411007, India
| | - Palak Agrawal
- Complement Biology Laboratory, National Centre for Cell Science, S. P. Pune University Campus, Pune - 411007, India
| | - Arvind Sahu
- Complement Biology Laboratory, National Centre for Cell Science, S. P. Pune University Campus, Pune - 411007, India.
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7
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Elias S, Kol I, Kahlon S, Amore R, Zeibak M, Mevorach D, Elchalal U, Zelig O, Mandelboim O. Anti-RhD antibody therapy modulates human natural killer cell function. Haematologica 2021; 106:1846-1856. [PMID: 32467141 PMCID: PMC8252960 DOI: 10.3324/haematol.2019.238097] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Indexed: 12/13/2022] Open
Abstract
Anti-RhD antibodies are widely used in clinical practice to prevent immunization against RhD, principally in hemolytic disease of the fetus and newborn. Intriguingly, this disease is induced by production of the very same antibodies when an RhD negative woman is pregnant with an RhD positive fetus. Despite over five decades of use, the mechanism of this treatment is, surprisingly, still unclear. Here we show that anti-RhD antibodies induce human natural killer (NK) cell degranulation. Mechanistically, we demonstrate that NK cell degranulation is mediated by binding of the Fc segment of anti-RhD antibodies to CD16, the main Fcγ receptor expressed on NK cells. We found that this CD16 activation is dependent upon glycosylation of the anti-RhD antibodies. Furthermore, we show that anti-RhD antibodies induce NK cell degranulation in vivo in patients who receive this treatment prophylactically. Finally, we demonstrate that the anti-RhD drug KamRho enhances the killing of dendritic cells. We suggest that this killing leads to reduced activation of adaptive immunity and may therefore affect the production of anti-RhD antibodies
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Affiliation(s)
- Shlomo Elias
- The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Inbal Kol
- The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Shira Kahlon
- The Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Rajaa Amore
- Department of Hematology, Hadassah - Hebrew University Medical Center, Jerusalem, Israel
| | - Mariam Zeibak
- Department of Hematology, Hadassah - Hebrew University Medical Center, Jerusalem, Israel
| | - Dror Mevorach
- Department of Hematology, Hadassah - Hebrew University Medical Center, Jerusalem, Israel
| | - Uriel Elchalal
- Dept. of Obstetrics and Gynecology, Hadassah - Hebrew University Medical Center, Jerusalem, Israel
| | - Orly Zelig
- Department of Hematology, Hadassah - Hebrew University Medical Center, Jerusalem, Israel
| | - Ofer Mandelboim
- The Hebrew University Hadassah Medical School, Jerusalem, Israel
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8
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Barati M, Javidi MA, Darvishi B, Shariatpanahi SP, Mesbah Moosavi ZS, Ghadirian R, Khani T, Sanati H, Simaee H, Shokrollahi Barough M, Farahmand L, Madjid Ansari A. Necroptosis triggered by ROS accumulation and Ca 2+ overload, partly explains the inflammatory responses and anti-cancer effects associated with 1Hz, 100 mT ELF-MF in vivo. Free Radic Biol Med 2021; 169:84-98. [PMID: 33857627 DOI: 10.1016/j.freeradbiomed.2021.04.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 02/06/2021] [Accepted: 04/02/2021] [Indexed: 12/26/2022]
Abstract
Whereas the anti-neoplastic activity of extremely low frequency magnetic fields (ELF-EMF) is well-documented in literature, little is known about its underlying anti-cancer mechanisms and induced types of cell death. Here, for the first time, we reported induction of necroptosis, a specific type of programed necrotic cell death, in MC4-L2 breast cancer cell lines following a 2 h/day exposure to a 100 Hz, 1 mT ELF-EMF for five days. For in vivo assessment, inbred BALB/c mice bearing established MC-4L2 tumors were exposed to 100 mT, 1 Hz ELF-EMF 2 h daily for a period of 28-day, following which tumors were dissected and fixed for evaluation of tumor biomarkers expression and types of cell death induced using TUNEL assay, Immunohistochemistry and H&E staining. Peripheral blood samples were also collected for assessing pro-inflammatory cytokine profile following exposure. An exaggerated proinflammatory response evident form enhancement of IFN-γ (4.8 ± 0.24 folds) and TNF-α (3.1 ± 0.19 folds) and number of tumors infiltrating lymphocytes (TILs), specially CD8+ Th cells (~20 folds), proposed occurrence of necroptosis in vivo. Meanwhile, exposure could effectively suppress tumor growth and expression of Ki-67, CD31, VEGFR2 and MMP-9. In vitro studies on ELF-EMF exposed MC-4L2 cells demonstrated a meaningful increase in phosphorylation of RIPK1/RIPK3/MLKL proteins and cleavage of caspase-9/caspase-3, confirming occurrence of both necroptosis and apoptosis. Complementary in vitro studies by treating ELF-EMF exposed MC-4L2 cells with verapamil (a calcium channel inhibitor), N-acetyl cysteine (a ROS scavenger) or calcium chloride confirmed the role of elevated intracellular calcium and ROS levels in ELF-EMF induced necroptosis.
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Affiliation(s)
- Mojdeh Barati
- Integrative Oncology Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Mohammad Amin Javidi
- Integrative Oncology Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Behrad Darvishi
- Recombinant Proteins Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | | | - Zahra S Mesbah Moosavi
- Muscle Health Research Centre, School of Kinesiology and Health Science, York University, Toronto, ON, Canada
| | - Reyhane Ghadirian
- Integrative Oncology Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Tahereh Khani
- Integrative Oncology Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Hassan Sanati
- ATMP Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Hossein Simaee
- Integrative Oncology Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | | | - Leila Farahmand
- Recombinant Proteins Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Alireza Madjid Ansari
- Integrative Oncology Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran.
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9
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Lokki AI, Teirilä L, Triebwasser M, Daly E, Bhattacharjee A, Uotila L, Llort Asens M, Kurki MI, Perola M, Auro K, Salmon JE, Daly M, Atkinson JP, Laivuori H, Fagerholm S, Meri S. Dysfunction of complement receptors CR3 (CD11b/18) and CR4 (CD11c/18) in pre-eclampsia: a genetic and functional study. BJOG 2021; 128:1282-1291. [PMID: 33539617 DOI: 10.1111/1471-0528.16660] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/01/2020] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To study genetic variants and their function within genes coding for complement receptors in pre-eclampsia. DESIGN A case-control study. SETTING Pre-eclampsia is a common vascular disease of pregnancy. The clearance of placenta-derived material is one of the functions of the complement system in pregnancy. POPULATION We genotyped 500 women with pre-eclamptic pregnancies and 190 pregnant women without pre-eclampsia, as controls, from the FINNPEC cohort, and 122 women with pre-eclamptic pregnancies and 1905 controls from the national FINRISK cohort. METHODS The functional consequences of genotypes discovered by targeted exomic sequencing were explored by analysing the binding of the main ligand iC3b to mutated CR3 or CR4, which were transiently expressed on the surface of COS-1 cells. MAIN OUTCOME MEASURES Allele frequencies were compared between pre-eclamptic pregnancies and controls in genetic studies. The functional consequences of selected variants were measured by binding assays. RESULTS The most significantly pre-eclampsia-linked CR3 variant M441K (P = 4.27E-4, OR = 1.401, 95% CI = 1.167-1.682) displayed a trend of increased adhesion to iC3b (P = 0.051). The CR4 variant A251T was found to enhance the adhesion of CR4 to iC3b, whereas W48R resulted in a decrease of the binding of CR4 to iC3b. CONCLUSIONS Results suggest that changes in complement-facilitated phagocytosis are associated with pre-eclampsia. Further studies are needed to ascertain whether aberrant CR3 and CR4 activity leads to altered pro- and anti-inflammatory cytokine responses in individuals carrying the associated variants, and the role of these receptors in pre-eclampsia pathogenesis. TWEETABLE ABSTRACT Genetic variants of complement receptors CR3 and CR4 have functional consequences that are associated with pre-eclampsia.
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Affiliation(s)
- A I Lokki
- Translational Immunology Research Program, Research Programs Unit, University of Helsinki, Helsinki, Finland.,Department of Obstetrics and Gynecology, Faculty of Medicine and Health Technology, Tampere University Hospital, Tampere University, Tampere, Finland
| | - L Teirilä
- Translational Immunology Research Program, Research Programs Unit, University of Helsinki, Helsinki, Finland.,Bacteriology and immunology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - M Triebwasser
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, Saint Louis, MO, USA
| | - E Daly
- Hospital and Harvard Medical School, Boston, MA, USA
| | - A Bhattacharjee
- Herantis Pharma Plc, Espoo, Finland.,Neuroscience Center, HiLife, University of Helsinki, Helsinki, Finland
| | - L Uotila
- Research Services, University of Helsinki, Helsinki, Finland
| | - M Llort Asens
- Molecular and Integrative Biosciences Research Program, Faculty of Bio- and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - M I Kurki
- Neurosurgery of Neuro Center, Kuopio University Hospital, Finland.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - M Perola
- Department of Health, National Institute for Health and Welfare, Helsinki, Finland
| | - K Auro
- Department of Government Services, National Institute for Health and Welfare, Helsinki, Finland
| | - J E Salmon
- Hospital for Special Surgery-Weill Cornell Medicine, Department of Medicine, New York, NY, USA
| | - M Daly
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA, USA.,Institute for Molecular Medicine Finland, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - J P Atkinson
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, Saint Louis, MO, USA
| | - H Laivuori
- Department of Obstetrics and Gynecology, Faculty of Medicine and Health Technology, Tampere University Hospital, Tampere University, Tampere, Finland.,Institute for Molecular Medicine Finland, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland.,Medical and Clinical Genetics, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - S Fagerholm
- Molecular and Integrative Biosciences Research Program, Faculty of Bio- and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - S Meri
- Translational Immunology Research Program, Research Programs Unit, University of Helsinki, Helsinki, Finland.,Bacteriology and immunology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
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- Medical and Clinical Genetics, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
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10
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Cai HQ, Weickert TW, Catts VS, Balzan R, Galletly C, Liu D, O'Donnell M, Shannon Weickert C. Altered levels of immune cell adhesion molecules are associated with memory impairment in schizophrenia and healthy controls. Brain Behav Immun 2020; 89:200-208. [PMID: 32540151 DOI: 10.1016/j.bbi.2020.06.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 06/02/2020] [Accepted: 06/09/2020] [Indexed: 01/25/2023] Open
Abstract
Increased cytokines and increased intercellular adhesion molecule-1 (ICAM1) found in the schizophrenia prefrontal cortex and in the blood may relate to cognitive deficits. Endothelial ICAM1 regulates immune cell trafficking into the brain by binding to integrins located on the surface of leukocytes. Whether the circulating levels of the main ICAM1 adhesion partners, lymphocyte-function associated antigen-1 (LFA1) and complement receptor 3 (CR3), both integrins, are altered in schizophrenia is unknown. Gene expressions of ICAM1, LFA1 and CR3 were measured in leukocytes from 86 schizophrenia patients and 77 controls. Participants were also administered cognitive testing to determine the extent to which cognitive ability was related to molecular measures of leukocyte adhesion. This cohort was previously stratified into inflammatory subgroups based on circulating cytokine mRNAs; thus, gene expressions were analysed by diagnosis and by inflammatory subgroups. Previously measured plasma ICAM1 protein was elevated in "high inflammation" schizophrenia compared to both "high" and "low inflammation" controls while ICAM1 mRNA was unchanged in leukocytes. LFA1 mRNA was decreased and CR3 mRNA was increased in leukocytes from people with schizophrenia compared to controls. LFA1 mRNA levels were positively correlated with working memory and elevated soluble ICAM1 was negatively correlated with verbal memory in schizophrenia. Altogether, some of the cognitive deficits in schizophrenia may be associated with altered expression of molecules that regulate immune cell trafficking.
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Affiliation(s)
- Helen Q Cai
- Schizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, Australia; School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Thomas W Weickert
- Schizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, Australia; School of Psychiatry, University of New South Wales, Sydney, Australia; Department of Neuroscience and Physiology, State University of New York Upstate Medical University, Syracuse, NY, USA
| | - Vibeke S Catts
- Schizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, Australia; School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Ryan Balzan
- Discipline of Psychiatry, University of Adelaide, Australia; College of Education, Psychology, and Social Work, Flinders University, Adelaide, Australia
| | - Cherrie Galletly
- Discipline of Psychiatry, University of Adelaide, Australia; Northern Adelaide Local Health Network, Adelaide, Australia; Ramsay Health Care (SA) Mental Health, Adelaide, Australia
| | - Dennis Liu
- Discipline of Psychiatry, University of Adelaide, Australia; Northern Adelaide Local Health Network, Adelaide, Australia
| | | | - Cynthia Shannon Weickert
- Schizophrenia Research Laboratory, Neuroscience Research Australia, Sydney, Australia; School of Psychiatry, University of New South Wales, Sydney, Australia; Department of Neuroscience and Physiology, State University of New York Upstate Medical University, Syracuse, NY, USA.
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11
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Bermejo-Jambrina M, Blatzer M, Jauregui-Onieva P, Yordanov TE, Hörtnagl P, Valovka T, Huber LA, Wilflingseder D, Posch W. CR4 Signaling Contributes to a DC-Driven Enhanced Immune Response Against Complement-Opsonized HIV-1. Front Immunol 2020; 11:2010. [PMID: 32922405 PMCID: PMC7457048 DOI: 10.3389/fimmu.2020.02010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 07/24/2020] [Indexed: 12/27/2022] Open
Abstract
Dendritic cells (DCs) possess intrinsic cellular defense mechanisms to specifically inhibit HIV-1 replication. In turn, HIV-1 has evolved strategies to evade innate immune sensing by DCs resulting in suboptimal maturation and poor antiviral immune responses. We previously showed that complement-opsonized HIV-1 (HIV-C) was able to efficiently infect various DC subsets significantly higher than non-opsonized HIV-1 (HIV) and therefore also mediate a higher antiviral immunity. Thus, complement coating of HIV-1 might play a role with respect to viral control occurring early during infection via modulation of DCs. To determine in detail which complement receptors (CRs) expressed on DCs was responsible for infection and superior pro-inflammatory and antiviral effects, we generated stable deletion mutants for the α-chains of CR3, CD11b, and CR4, CD11c using CRISPR/Cas9 in THP1-derived DCs. We found that CD11c deletion resulted in impaired DC infection as well as antiviral and pro-inflammatory immunity upon exposure to complement-coated HIV-1. In contrast, sole expression of CD11b on DCs shifted the cells to an anti-inflammatory, regulatory DC type. We here illustrated that CR4 comprised of CD11c and CD18 is the major player with respect to DC infection associated with a potent early pro-inflammatory immune response. A more detailed characterization of CR3 and CR4 functions using our powerful tool might open novel avenues for early therapeutic intervention during HIV-1 infection.
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Affiliation(s)
- Marta Bermejo-Jambrina
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria.,Department of Experimental Immunology, Amsterdam Infection and Immunity Institute, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Michael Blatzer
- Experimental Neuropathology Unit, Infection and Epidemiology Department, Institute Pasteur, Paris, France
| | - Paula Jauregui-Onieva
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Teodor E Yordanov
- Institute of Cell Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Paul Hörtnagl
- Central Institute for Blood Transfusion and Immunological Department, Innsbruck, Austria
| | - Taras Valovka
- Institute of Cell Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria.,Department of Pediatrics I, Medical University of Innsbruck, Innsbruck, Austria
| | - Lukas A Huber
- Institute of Cell Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Doris Wilflingseder
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Wilfried Posch
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
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12
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Xu W, Zhang Y, Wang X, Liu P, Gao D, Gu B, Zhang J, Li C, Ren Q, Yang L, Yuan H, Shen M, Chen X. Clinical features and expression of type I interferon-inducible genes in systemic lupus erythematosus patients harboring rs1143679 polymorphism in China: a single-center, retrospective study. Clin Rheumatol 2020; 40:1093-1101. [PMID: 32785810 DOI: 10.1007/s10067-020-05330-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 07/02/2020] [Accepted: 08/04/2020] [Indexed: 11/27/2022]
Abstract
OBJECTIVE This case-control study aimed to analyze the clinical features and determine the expression of type I interferon-induced genes in systemic lupus erythematosus (SLE) patients harboring the CD11b rs1143679 single-nucleotide polymorphism (SNP) and elucidate whether it is involved in the relapses of SLE. METHODS One hundred twenty-five relatively inactive SLE patients with SLEDAI scores < 6, including 102 CD11b rs1143679 G allele patients as controls and 23 rs1143679 A allele carriers as cases, were enrolled from the SLE patient specimen bank in the Department of Rheumatology and Immunology. The sample set was retrospectively analyzed for differences in clinical features, and quantitative PCR and Western blot analyses were performed to evaluate the relative expression of type I interferon (IFN)-inducible genes. RESULTS The 24-h urinary protein levels in the case group were significantly elevated, and serum C3 levels were significantly reduced compared with those in the control group (P = 0.019 and P = 0.021, respectively). The relative mRNA levels of IFN-inducible genes IFIT1, IFIT4, and ISG15 in the case group were higher than that in the control group (P = 0.0257, 0.0344, and 0.0311, respectively) and matched with the Western blot results. CONCLUSIONS The relative expression of type I IFN-inducible genes in inactive SLE patients harboring the CD11b rs1143679 polymorphism was higher than that in other lupus patients. These findings suggest that the rs1143679 SNP can precipitate relapses in inactive SLE patients. KEY POINTS • The rs1143679 GA genotype was associated with SLE clinical features. • The rs1143679 GA genotype showed higher interferon-inducible gene expression relative to the GG genotype.
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Affiliation(s)
- Wenyu Xu
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Yueyue Zhang
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Xiaoqin Wang
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Peiyu Liu
- Department of Pharmacology, School of Basic Medical Science, Nanjing Medical University, Nanjing, 211166, China
| | - Dayu Gao
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Bingjie Gu
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Junyu Zhang
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Chunmei Li
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Qijie Ren
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Leilei Yang
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Hai Yuan
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Minning Shen
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China
| | - Xingguo Chen
- Department of Rheumatology and Immunology, Nanjing First Hospital, Nanjing Medical University, No. 68 Changle Road, Nanjing, 210006, China.
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13
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Skopelja-Gardner S, Colonna L, Hermanson P, Sun X, Tanaka L, Tai J, Nguyen Y, Snyder JM, Alpers CE, Hudkins KL, Salant DJ, Peng Y, Elkon KB. Complement Deficiencies Result in Surrogate Pathways of Complement Activation in Novel Polygenic Lupus-like Models of Kidney Injury. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2020; 204:2627-2640. [PMID: 32238460 PMCID: PMC7365257 DOI: 10.4049/jimmunol.1901473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/15/2020] [Indexed: 12/27/2022]
Abstract
Lupus nephritis (LN) is a major contributor to morbidity and mortality in lupus patients, but the mechanisms of kidney damage remain unclear. In this study, we introduce, to our knowledge, novel models of LN designed to resemble the polygenic nature of human lupus by embodying three key genetic alterations: the Sle1 interval leading to anti-chromatin autoantibodies; Mfge8-/- , leading to defective clearance of apoptotic cells; and either C1q-/- or C3-/- , leading to low complement levels. We report that proliferative glomerulonephritis arose only in the presence of all three abnormalities (i.e., in Sle1.Mfge8 -/- C1q -/- and Sle1.Mfge8 -/- C3 -/- triple-mutant [TM] strains [C1q -/-TM and C3-/- TM, respectively]), with structural kidney changes resembling those in LN patients. Unexpectedly, both TM strains had significant increases in autoantibody titers, Ag spread, and IgG deposition in the kidneys. Despite the early complement component deficiencies, we observed assembly of the pathogenic terminal complement membrane attack complex in both TM strains. In C1q-/- TM mice, colocalization of MASP-2 and C3 in both the glomeruli and tubules indicated that the lectin pathway likely contributed to complement activation and tissue injury in this strain. Interestingly, enhanced thrombin activation in C3-/- TM mice and reduction of kidney injury following attenuation of thrombin generation by argatroban in a serum-transfer nephrotoxic model identified thrombin as a surrogate pathway for complement activation in C3-deficient mice. These novel mouse models of human lupus inform the requirements for nephritis and provide targets for intervention.
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Affiliation(s)
| | - Lucrezia Colonna
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Payton Hermanson
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Xizhang Sun
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Lena Tanaka
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Joyce Tai
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Yenly Nguyen
- Division of Rheumatology, University of Washington, Seattle, WA 98109
| | - Jessica M Snyder
- Department of Comparative Medicine, University of Washington, Seattle, WA 98109
| | - Charles E Alpers
- Department of Nephrology, University of Washington, Seattle, WA 98109
| | - Kelly L Hudkins
- Department of Nephrology, University of Washington, Seattle, WA 98109
| | - David J Salant
- Division of Nephrology, Boston University, Boston, MA 02215; and
| | - YuFeng Peng
- Division of Rheumatology, University of Washington, Seattle, WA 98109;
| | - Keith B Elkon
- Division of Rheumatology, University of Washington, Seattle, WA 98109;
- Department of Immunology, University of Washington, Seattle, WA 98109
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14
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Makou E, Bailey RG, Johnston H, Parkin JD, Hulme AN, Hähner G, Barlow PN. Combining SPR with atomic-force microscopy enables single-molecule insights into activation and suppression of the complement cascade. J Biol Chem 2019; 294:20148-20163. [PMID: 31719147 PMCID: PMC6937562 DOI: 10.1074/jbc.ra119.010913] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 11/07/2019] [Indexed: 12/05/2022] Open
Abstract
Activation and suppression of the complement system compete on every serum-exposed surface, host or foreign. Potentially harmful outcomes of this competition depend on surface molecules through mechanisms that remain incompletely understood. Combining surface plasmon resonance (SPR) with atomic force microscopy (AFM), here we studied two complement system proteins at the single-molecule level: C3b, the proteolytically activated form of C3, and factor H (FH), the surface-sensing C3b-binding complement regulator. We used SPR to monitor complement initiation occurring through a positive-feedback loop wherein surface-deposited C3b participates in convertases that cleave C3, thereby depositing more C3b. Over multiple cycles of flowing factor B, factor D, and C3 over the SPR chip, we amplified C3b from ∼20 to ∼220 molecules·μm−2. AFM revealed C3b clusters of up to 20 molecules and solitary C3b molecules deposited up to 200 nm away from the clusters. A force of 0.17 ± 0.02 nanonewtons was needed to pull a single FH molecule, anchored to the AFM probe, from its complex with surface-attached C3b. The extent to which FH molecules stretched before detachment varied widely among complexes. Performing force-distance measurements with FH(D1119G), a variant lacking one of the C3b-binding sites and causing atypical hemolytic uremic syndrome, we found that it detached more uniformly and easily. In further SPR experiments, KD values between FH and C3b on a custom-made chip surface were 5-fold tighter than on commercial chips and similar to those on erythrocytes. These results suggest that the chemistry at the surface on which FH acts drives conformational adjustments that are functionally critical.
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Affiliation(s)
- Elisavet Makou
- EaStChem School of Chemistry, University of Edinburgh, Joseph Black Chemistry Building, Edinburgh, Scotland EH9 3FJ, United Kingdom
| | - Richard G Bailey
- EaStChem School of Chemistry, University of St. Andrews, St Andrews, Scotland KY16 9ST, United Kingdom
| | - Heather Johnston
- EaStChem School of Chemistry, University of Edinburgh, Joseph Black Chemistry Building, Edinburgh, Scotland EH9 3FJ, United Kingdom
| | - John D Parkin
- EaStChem School of Chemistry, University of St. Andrews, St Andrews, Scotland KY16 9ST, United Kingdom
| | - Alison N Hulme
- EaStChem School of Chemistry, University of Edinburgh, Joseph Black Chemistry Building, Edinburgh, Scotland EH9 3FJ, United Kingdom
| | - Georg Hähner
- EaStChem School of Chemistry, University of St. Andrews, St Andrews, Scotland KY16 9ST, United Kingdom
| | - Paul N Barlow
- EaStChem School of Chemistry, University of Edinburgh, Joseph Black Chemistry Building, Edinburgh, Scotland EH9 3FJ, United Kingdom .,School of Biological Sciences, University of Edinburgh, Edinburgh, Scotland EH9 3JY, United Kingdom
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15
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Regulation of the complement system and immunological tolerance in pregnancy. Semin Immunol 2019; 45:101337. [PMID: 31757607 DOI: 10.1016/j.smim.2019.101337] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 10/24/2019] [Indexed: 12/18/2022]
Abstract
Preeclampsia is a serious vascular complication of the human pregnancy, whose etiology is still poorly understood. In preeclampsia, exacerbated apoptosis and fragmentation of the placental tissue occurs due to developmental qualities of the placental trophoblast cells and/or mechanical and oxidative distress to the syncytiotrophoblast, which lines the placental villi. Dysregulation of the complement system is recognized as one of the mechanisms of the disease pathology. Complement has the ability to promote inflammation and facilitate phagocytosis of placenta-derived particles and apoptotic cells by macrophages. In preeclampsia, an overload of placental cell damage or dysregulated complement system may lead to insufficient clearance of apoptotic particles and placenta-derived debris. Excess placental damage may lead to sequestration of microparticles, such as placental vesicles, to capillaries in the glomeruli of the kidney and other vulnerable tissues. This phenomenon could contribute to the manifestations of typical diagnostic symptoms of preeclampsia: proteinuria and new-onset hypertension. In this review we propose that the complement system may serve as a regulator of the complex tolerance and clearance processes that are fundamental in healthy pregnancy. It is therefore recommended that further research be conducted to elucidate the interactions between components of the complement system and immune responses in the context of complicated and healthy pregnancy.
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16
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Bogomolova AM, Shavva VS, Nikitin AA, Nekrasova EV, Dizhe EB, Larionova EE, Kudriavtsev IV, Orlov SV. Hypoxia as a Factor Involved in the Regulation of the apoA-1, ABCA1, and Complement C3 Gene Expression in Human Macrophages. BIOCHEMISTRY (MOSCOW) 2019; 84:529-539. [DOI: 10.1134/s0006297919050079] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Ma Y, Liu Y, Zhang Z, Yang GY. Significance of Complement System in Ischemic Stroke: A Comprehensive Review. Aging Dis 2019; 10:429-462. [PMID: 31011487 PMCID: PMC6457046 DOI: 10.14336/ad.2019.0119] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/19/2019] [Indexed: 12/14/2022] Open
Abstract
The complement system is an essential part of innate immunity, typically conferring protection via eliminating pathogens and accumulating debris. However, the defensive function of the complement system can exacerbate immune, inflammatory, and degenerative responses in various pathological conditions. Cumulative evidence indicates that the complement system plays a critical role in the pathogenesis of ischemic brain injury, as the depletion of certain complement components or the inhibition of complement activation could reduce ischemic brain injury. Although multiple candidates modulating or inhibiting complement activation show massive potential for the treatment of ischemic stroke, the clinical availability of complement inhibitors remains limited. The complement system is also involved in neural plasticity and neurogenesis during cerebral ischemia. Thus, unexpected side effects could be induced if the systemic complement system is inhibited. In this review, we highlighted the recent concepts and discoveries of the roles of different kinds of complement components, such as C3a, C5a, and their receptors, in both normal brain physiology and the pathophysiology of brain ischemia. In addition, we comprehensively reviewed the current development of complement-targeted therapy for ischemic stroke and discussed the challenges of bringing these therapies into the clinic. The design of future experiments was also discussed to better characterize the role of complement in both tissue injury and recovery after cerebral ischemia. More studies are needed to elucidate the molecular and cellular mechanisms of how complement components exert their functions in different stages of ischemic stroke to optimize the intervention of targeting the complement system.
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Affiliation(s)
- Yuanyuan Ma
- 1Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Yanqun Liu
- 3Department of Neurology, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Zhijun Zhang
- 2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Guo-Yuan Yang
- 1Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
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18
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Fagerholm SC, Guenther C, Llort Asens M, Savinko T, Uotila LM. Beta2-Integrins and Interacting Proteins in Leukocyte Trafficking, Immune Suppression, and Immunodeficiency Disease. Front Immunol 2019; 10:254. [PMID: 30837997 PMCID: PMC6389632 DOI: 10.3389/fimmu.2019.00254] [Citation(s) in RCA: 97] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 01/29/2019] [Indexed: 12/21/2022] Open
Abstract
Beta2-integrins are complex leukocyte-specific adhesion molecules that are essential for leukocyte (e.g., neutrophil, lymphocyte) trafficking, as well as for other immunological processes such as neutrophil phagocytosis and ROS production, and T cell activation. Intriguingly, however, they have also been found to negatively regulate cytokine responses, maturation, and migratory responses in myeloid cells such as macrophages and dendritic cells, revealing new, and unexpected roles of these molecules in immunity. Because of their essential role in leukocyte function, a lack of expression or function of beta2-integrins causes rare immunodeficiency syndromes, Leukocyte adhesion deficiency type I, and type III (LAD-I and LAD-III). LAD-I is caused by reduced or lost expression of beta2-integrins, whilst in LAD-III, beta2-integrins are expressed but dysfunctional because a major integrin cytoplasmic regulator, kindlin-3, is mutated. Interestingly, some LAD-related phenotypes such as periodontitis have recently been shown to be due to an uncontrolled inflammatory response rather than to an uncontrolled infection, as was previously thought. This review will focus on the recent advances concerning the regulation and functions of beta2-integrins in leukocyte trafficking, immune suppression, and immune deficiency disease.
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Affiliation(s)
- Susanna C Fagerholm
- Molecular and Integrative Biosciences Research Program, Faculty of Bio- and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Carla Guenther
- Molecular and Integrative Biosciences Research Program, Faculty of Bio- and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Marc Llort Asens
- Molecular and Integrative Biosciences Research Program, Faculty of Bio- and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | | | - Liisa M Uotila
- Research Services, University of Helsinki, Helsinki, Finland
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19
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Thieblemont N, Witko-Sarsat V, Ariel A. Regulation of macrophage activation by proteins expressed on apoptotic neutrophils: Subversion towards autoimmunity by proteinase 3. Eur J Clin Invest 2018; 48 Suppl 2:e12990. [PMID: 30039869 DOI: 10.1111/eci.12990] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 06/27/2018] [Indexed: 12/13/2022]
Abstract
Neutrophils are critically involved in host defence and they also modulate the inflammatory process. Turning the inflammatory response towards a resolutive outcome requires a dialogue between apoptotic neutrophils and proresolving macrophages through complex key molecular interactions controlling efferocytosis, anti-inflammatory reprogramming and ultimately immune regulation. In this review, we will first focus on recent molecular analyses aiming at characterizing the role of proteins expressed on apoptotic neutrophils and their cognate partners expressed on macrophages in the resolution of inflammation. These will include chemokine receptors and their ligands and annexin A1 and its receptor FPR2. We will next depict how the structural and enzymatic properties of proteinase 3 (PR3), the autoantigen in vasculitis, allow its expression on apoptotic neutrophils, which in turn affects efferocytosis and immune response associated with the clearance of apoptotic cells. This example illustrates that the fate of apoptotic neutrophils directly influences the resolution of inflammation and immune responses thereby potentially contributing to systemic and nonresolving inflammation as well as autoimmunity.
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Affiliation(s)
- Nathalie Thieblemont
- INSERM U1016 Cochin Institute, Paris, France.,CNRS UMR 8104, Paris, France.,Université Paris-Descartes, Paris, France.,Center of Excellence LABEX Inflamex, Paris, France
| | - Véronique Witko-Sarsat
- INSERM U1016 Cochin Institute, Paris, France.,CNRS UMR 8104, Paris, France.,Université Paris-Descartes, Paris, France.,Center of Excellence LABEX Inflamex, Paris, France
| | - Amiram Ariel
- Department of Biology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
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20
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Nowatzky J, Manches O, Khan SA, Godefroy E, Bhardwaj N. Modulation of human Th17 cell responses through complement receptor 3 (CD11 b/CD18) ligation on monocyte-derived dendritic cells. J Autoimmun 2018; 92:57-66. [PMID: 29908907 DOI: 10.1016/j.jaut.2018.05.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 04/30/2018] [Accepted: 05/08/2018] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Apoptotic cell receptors contribute to the induction of tolerance by modulating dendritic cell function following the uptake of apoptotic cells or microparticles. Dendritic cells that have bound or ingested apoptotic cells produce only low amounts of pro-inflammatory cytokines and fail to prime effector T cell responses. Specifically, ligation of the apoptotic cell receptor CR3 (CD11 b/CD18) on human monocyte-derived dendritic cells (moDC) down-modates proinflammatory cytokine secretion, but the consequences for human Th17 cell homeostasis and effector responses remain unknown. Here, we aimed to establish whether CD11b-ligated moDC modulate Th17 cell effector reponses to assess their potential for future use in moDC-based suppressive immunotherapy. METHODS We generated a bead-based surrogate system to target CD11b on monocyte-derived human dendritic cells and examined the effects of CD11b ligation on Th17-skewing cytokine secretion, priming, expansion and functional plasticity in DC/T cell co-culture systems at the poly- and monoclonal level. RESULTS We show that Th17 cell expansion within the human memory CD4+ T cell compartment was efficiently constricted by targeting the CD11b receptor on moDC. This tolerogenic capacity was primarily dependent on cytokine skewing. Furthermore, ligation of CD11b on healthy homozygous carriers of the rs11143679 (ITGAM) variant - a strong genetic susceptibility marker for human systemic lupus erythematosus - also down-modulated the secretion of Th17-skewing cytokines. CONCLUSION Overall, our findings underline the potential of targeted CD11b ligation on human dendritic cells for the engineering of suppressive immunotherapy for Th17-related autoimmune disorders.
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Affiliation(s)
| | | | | | | | - Nina Bhardwaj
- New York University School of Medicine, New York, NY, USA.
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21
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Complement links platelets to innate immunity. Semin Immunol 2018; 37:43-52. [DOI: 10.1016/j.smim.2018.01.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 01/30/2018] [Accepted: 01/31/2018] [Indexed: 12/11/2022]
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22
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Khan SQ, Khan I, Gupta V. CD11b Activity Modulates Pathogenesis of Lupus Nephritis. Front Med (Lausanne) 2018; 5:52. [PMID: 29600248 PMCID: PMC5862812 DOI: 10.3389/fmed.2018.00052] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Accepted: 02/13/2018] [Indexed: 01/01/2023] Open
Abstract
Lupus nephritis (LN) is a common complication of systemic lupus erythematosus (SLE) with unclear etiology and limited treatment options. Immune cell infiltration into the kidneys, a hallmark of LN, triggers tissue damage and proteinuria. CD11b, the α-chain of integrin receptor CD11b/CD18 (also known as αMβ2, Mac-1, and CR3), is highly expressed on the surface of innate immune cells, including macrophages and neutrophils. Genetic variants in the human ITGAM gene, which encodes for CD11b, are strongly associated with susceptibility to SLE, LN, and other complications of SLE. CD11b modulates several key biological functions in innate immune cells, including cell adhesion, migration, and phagocytosis. CD11b also modulates other signaling pathways in these cells, such as the Toll-like receptor signaling pathways, that mediate generation of type I interferons, a key proinflammatory cytokine and circulating biomarker in SLE and LN patients. However, how variants in ITGAM gene contribute to disease pathogenesis has not been completely established. Here, we provide an overview of CD11b modulated mechanisms and the functional consequences of the genetic variants that can drive disease pathogenesis. We also present recent insights from studies after pharmacological activation of CD11b. These studies offer novel mechanisms for development of therapeutics for LN, SLE and other autoimmune diseases.
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Affiliation(s)
- Samia Q Khan
- Drug Discovery Center, Department of Internal Medicine, Rush University Medical School, Chicago, IL, United States
| | - Imran Khan
- Drug Discovery Center, Department of Internal Medicine, Rush University Medical School, Chicago, IL, United States
| | - Vineet Gupta
- Drug Discovery Center, Department of Internal Medicine, Rush University Medical School, Chicago, IL, United States
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23
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Liu CF, Min XY, Wang N, Wang JX, Ma N, Dong X, Zhang B, Wu W, Li ZF, Zhou W, Li K. Complement Receptor 3 Has Negative Impact on Tumor Surveillance through Suppression of Natural Killer Cell Function. Front Immunol 2017; 8:1602. [PMID: 29209332 PMCID: PMC5702005 DOI: 10.3389/fimmu.2017.01602] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 11/06/2017] [Indexed: 01/31/2023] Open
Abstract
Complement receptor 3 (CR3) is expressed abundantly on natural killer (NK) cells; however, whether it plays roles in NK cell-dependent tumor surveillance is largely unknown. Here, we show that CR3 is an important negative regulator of NK cell function, which has negative impact on tumor surveillance. Mice deficient in CR3 (CD11b-/- mice) exhibited a more activated NK phenotype and had enhanced NK-dependent tumor killing. In a B16-luc melanoma-induced lung tumor growth and metastasis model, mice deficient in CR3 had reduced tumor growth and metastases, compared with WT mice. In addition, adaptive transfer of NK cells lacking CR3 (into NK-deficient mice) mediated more efficient suppression of tumor growth and metastases, compared with the transfer of CR3 sufficient NK cells, suggesting that CR3 can impair tumor surveillance through suppression of NK cell function. In vitro analyses showed that engagement of CR3 with iC3b (classical CR3 ligand) on NK cells negatively regulated NK cell activity and effector functions (i.e. direct tumor cell killing, antibody-dependent NK-mediated tumor killing). Cell signaling analyses showed that iC3b stimulation caused activation of Src homology 2 domain-containing inositol-5-phosphatase-1 (SHIP-1) and JNK, and suppression of ERK in NK cells, supporting that iC3b mediates negative regulation of NK cell function through its effects on SHIP-1, JNK, and ERK signal transduction pathways. Thus, our findings demonstrate a previously unknown role for CR3 in dysregulation of NK-dependent tumor surveillance and suggest that the iC3b/CR3 signaling is a critical negative regulator of NK cell function and may represent a new target for preserving NK cell function in cancer patients and improving NK cell-based therapy.
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Affiliation(s)
- Cheng-Fei Liu
- Core Research Laboratory, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Xiao-Yun Min
- Core Research Laboratory, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Naiyin Wang
- Medical Research Council (MRC) Centre for Transplantation, King's College London, Guy's Hospital, London, United Kingdom
| | - Jia-Xing Wang
- Core Research Laboratory, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Ning Ma
- Core Research Laboratory, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Xia Dong
- Medical Research Council (MRC) Centre for Transplantation, King's College London, Guy's Hospital, London, United Kingdom
| | - Bing Zhang
- Core Research Laboratory, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China
| | - Weiju Wu
- Medical Research Council (MRC) Centre for Transplantation, King's College London, Guy's Hospital, London, United Kingdom
| | - Zong-Fang Li
- National Local Joint Engineering Research Centre of Biodiagnostics and Biotherapy, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China.,Shaanxi Provincial Clinical Research Center for Hepatic & Splenic Diseases, Xi'an, China
| | - Wuding Zhou
- Medical Research Council (MRC) Centre for Transplantation, King's College London, Guy's Hospital, London, United Kingdom
| | - Ke Li
- Core Research Laboratory, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China.,National Local Joint Engineering Research Centre of Biodiagnostics and Biotherapy, The Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, China
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24
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Trahtemberg U, Mevorach D. Apoptotic Cells Induced Signaling for Immune Homeostasis in Macrophages and Dendritic Cells. Front Immunol 2017; 8:1356. [PMID: 29118755 PMCID: PMC5661053 DOI: 10.3389/fimmu.2017.01356] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 10/03/2017] [Indexed: 12/24/2022] Open
Abstract
Inefficient and abnormal clearance of apoptotic cells (efferocytosis) contributes to systemic autoimmune disease in humans and mice, and inefficient chromosomal DNA degradation by DNAse II leads to systemic polyarthritis and a cytokine storm. By contrast, efficient clearance allows immune homeostasis, generally leads to a non-inflammatory state for both macrophages and dendritic cells (DCs), and contributes to maintenance of peripheral tolerance. As many as 3 × 108 cells undergo apoptosis every hour in our bodies, and one of the primary “eat me” signals expressed by apoptotic cells is phosphatidylserine (PtdSer). Apoptotic cells themselves are major contributors to the “anti-inflammatory” nature of the engulfment process, some by secreting thrombospondin-1 (TSP-1) or adenosine monophosphate and possibly other immune modulating “calm-down” signals that interact with macrophages and DCs. Apoptotic cells also produce “find me” and “tolerate me” signals to attract and immune modulate macrophages and DCs that express specific receptors for some of these signals. Neither macrophages nor DCs are uniform, and each cell type may variably express membrane proteins that function as receptors for PtdSer or for opsonins like complement or opsonins that bind to PtdSer, such as protein S and growth arrest-specific 6. Macrophages and DCs also express scavenger receptors, CD36, and integrins that function via bridging molecules such as TSP-1 or milk fat globule-EGF factor 8 protein and that differentially engage in various multi-ligand interactions between apoptotic cells and phagocytes. In this review, we describe the anti-inflammatory and pro-homeostatic nature of apoptotic cell interaction with the immune system. We do not review some forms of immunogenic cell death. We summarize the known apoptotic cell signaling events in macrophages and DCs that are related to toll-like receptors, nuclear factor kappa B, inflammasome, the lipid-activated nuclear receptors, Tyro3, Axl, and Mertk receptors, as well as induction of signal transducer and activator of transcription 1 and suppressor of cytokine signaling that lead to immune system silencing and DC tolerance. These properties of apoptotic cells are the mechanisms that enable their successful use as therapeutic modalities in mice and humans in various autoimmune diseases, organ transplantation, graft-versus-host disease, and sepsis.
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Affiliation(s)
- Uriel Trahtemberg
- General Intensive Care Unit, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Dror Mevorach
- Rheumatology Research Center, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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25
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Daigo K, Inforzato A, Barajon I, Garlanda C, Bottazzi B, Meri S, Mantovani A. Pentraxins in the activation and regulation of innate immunity. Immunol Rev 2017; 274:202-217. [PMID: 27782337 DOI: 10.1111/imr.12476] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Humoral fluid phase pattern recognition molecules (PRMs) are a key component of the activation and regulation of innate immunity. Humoral PRMs are diverse. We focused on the long pentraxin PTX3 as a paradigmatic example of fluid phase PRMs. PTX3 acts as a functional ancestor of antibodies and plays a non-redundant role in resistance against selected microbes in mouse and man and in the regulation of inflammation. This molecule interacts with complement components, thus modulating complement activation. In particular, PTX3 regulates complement-driven macrophage-mediated tumor progression, acting as an extrinsic oncosuppressor in preclinical models and selected human tumors. Evidence collected over the years suggests that PTX3 is a biomarker and potential therapeutic agent in humans, and pave the way to translation of this molecule into the clinic.
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Affiliation(s)
- Kenji Daigo
- Department of Inflammation and Immunology, Humanitas Clinical and Research Center, Rozzano (Milan), Italy
| | - Antonio Inforzato
- Department of Inflammation and Immunology, Humanitas Clinical and Research Center, Rozzano (Milan), Italy.,Department of Medical Biotechnologies and Translational Medicine, University of Milan, Italy
| | | | - Cecilia Garlanda
- Department of Inflammation and Immunology, Humanitas Clinical and Research Center, Rozzano (Milan), Italy
| | - Barbara Bottazzi
- Department of Inflammation and Immunology, Humanitas Clinical and Research Center, Rozzano (Milan), Italy
| | - Seppo Meri
- Immunobiology Research Program, Research Programs Unit, Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki , Helsinki , Finland
| | - Alberto Mantovani
- Department of Inflammation and Immunology, Humanitas Clinical and Research Center, Rozzano (Milan), Italy.,Humanitas University, Rozzano, Italy
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26
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Zhou H, Olsen H, So E, Mérigeon E, Rybin D, Owens J, LaRosa G, Block DS, Strome SE, Zhang X. A fully recombinant human IgG1 Fc multimer (GL-2045) inhibits complement-mediated cytotoxicity and induces iC3b. Blood Adv 2017; 1:504-515. [PMID: 29296968 PMCID: PMC5728453 DOI: 10.1182/bloodadvances.2016001917] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 02/15/2017] [Indexed: 12/16/2022] Open
Abstract
GL-2045 is a recombinant human immunoglobulin G1 (IgG1)-based Fc multimer designed to recapitulate the anti-inflammatory activities of intravenous immunoglobulin (IVIG) on the innate and adaptive immune responses. We used functional in vitro studies to determine if GL-2045 could mimic the modulatory activity of IVIG on complement activation. GL-2045, at log-order lower concentrations than heat-aggregated IgG (HAGG) and IVIG, protected antibody-opsonized cells from complement-dependent cytotoxicity. These protective effects were completely mediated by the higher order multimer fractions of GL-2045 and were partially dependent upon sequestration of C1q. Exposure of serum to GL-2045 and, to a lesser extent, IVIG, resulted in high levels of C4a, limited levels of C3a, and no C5a. In contrast, HAGG induced high levels of C4a, C3a, and C5a. The means by which GL-2045 governed complement activation was dependent on its ability to augment the function of factor H, alone and in combination with factor I, to indirectly limit the alternative form of C3 convertase, with resultant increases in the anti-inflammatory molecule, the "inactive" form of C3b, called iC3b. Although IVIG, like GL-2045, potentiated factor H function, it also directly inhibited the alternative form of C3 convertase. Our findings help elucidate how IVIG, GL-2045, and HAGG regulate complement function. Furthermore, the capacity of GL-2045 to sequester C1q and augment factor H activity, in combination with its ability to generate activation-induced immunomodulatory complement split products, such as iC3b, make it a viable drug candidate for the treatment of diverse complement-mediated diseases.
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Affiliation(s)
- Hua Zhou
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD
| | | | - Edward So
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD
| | | | | | | | | | | | - Scott E Strome
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD
| | - Xiaoyu Zhang
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Maryland School of Medicine, Baltimore, MD
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27
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Kourtzelis I, Mitroulis I, von Renesse J, Hajishengallis G, Chavakis T. From leukocyte recruitment to resolution of inflammation: the cardinal role of integrins. J Leukoc Biol 2017; 102:677-683. [PMID: 28292945 DOI: 10.1189/jlb.3mr0117-024r] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 02/21/2017] [Accepted: 02/23/2017] [Indexed: 12/23/2022] Open
Abstract
Integrins constitute a large group of adhesion receptors that are formed as heterodimers of α and β subunits. Their presence and activation status on the surface of leukocytes modulate a broad spectrum of processes in inflammation and immunity. This mini review critically outlines research advances with regard to the function of leukocyte integrins in regulating and integrating the onset and resolution of acute inflammation. Specifically, we summarize and discuss relevant, current literature that supports the multifunctional role of integrins and their partners. The latter include molecules that physically associate with integrins or regulate their activity in the context of the following: 1) leukocyte recruitment to an inflamed tissue, 2) recognition and phagocytosis of apoptotic neutrophils (efferocytosis), and 3) egress of efferocytic macrophages from the inflamed site to lymphoid tissues. The understanding of the fine-tuning mechanisms of the aforementioned processes by integrins and their functional partners may enable the design of therapeutic tools to counteract destructive inflammation and promote more efficient resolution of inflammation.
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Affiliation(s)
- Ioannis Kourtzelis
- Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany; and
| | - Ioannis Mitroulis
- Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany; and
| | - Janusz von Renesse
- Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany; and
| | - George Hajishengallis
- Department of Microbiology, University of Pennsylvania, School of Dental Medicine, Philadelphia, Pennsylvania, USA
| | - Triantafyllos Chavakis
- Institute for Clinical Chemistry and Laboratory Medicine, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany; and
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28
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Ferluga J, Kouser L, Murugaiah V, Sim RB, Kishore U. Potential influences of complement factor H in autoimmune inflammatory and thrombotic disorders. Mol Immunol 2017; 84:84-106. [PMID: 28216098 DOI: 10.1016/j.molimm.2017.01.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Revised: 01/11/2017] [Accepted: 01/13/2017] [Indexed: 01/01/2023]
Abstract
Complement system homeostasis is important for host self-protection and anti-microbial immune surveillance, and recent research indicates roles in tissue development and remodelling. Complement also appears to have several points of interaction with the blood coagulation system. Deficiency and altered function due to gene mutations and polymorphisms in complement effectors and regulators, including Factor H, have been associated with familial and sporadic autoimmune inflammatory - thrombotic disorders, in which autoantibodies play a part. These include systemic lupus erythematosus, rheumatoid arthritis, atypical haemolytic uremic syndrome, anti-phospholipid syndrome and age-related macular degeneration. Such diseases are generally complex - multigenic and heterogeneous in their symptoms and predisposition/susceptibility. They usually need to be triggered by vascular trauma, drugs or infection and non-complement genetic factors also play a part. Underlying events seem to include decline in peripheral regulatory T cells, dendritic cell, and B cell tolerance, associated with alterations in lymphoid organ microenvironment. Factor H is an abundant protein, synthesised in many cell types, and its reported binding to many different ligands, even if not of high affinity, may influence a large number of molecular interactions, together with the accepted role of Factor H within the complement system. Factor H is involved in mesenchymal stem cell mediated tolerance and also contributes to self-tolerance by augmenting iC3b production and opsonisation of apoptotic cells for their silent dendritic cell engulfment via complement receptor CR3, which mediates anti-inflammatory-tolerogenic effects in the apoptotic cell context. There may be co-operation with other phagocytic receptors, such as complement C1q receptors, and the Tim glycoprotein family, which specifically bind phosphatidylserine expressed on the apoptotic cell surface. Factor H is able to discriminate between self and nonself surfaces for self-protection and anti-microbe defence. Factor H, particularly as an abundant platelet protein, may also modulate blood coagulation, having an anti-thrombotic role. Here, we review a number of interaction pathways in coagulation and in immunity, together with associated diseases, and indicate where Factor H may be expected to exert an influence, based on reports of the diversity of ligands for Factor H.
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Affiliation(s)
- Janez Ferluga
- Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, United Kingdom
| | - Lubna Kouser
- Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, United Kingdom
| | - Valarmathy Murugaiah
- Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, United Kingdom
| | - Robert B Sim
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
| | - Uday Kishore
- Biosciences, College of Health and Life Sciences, Brunel University London, Uxbridge, UB8 3PH, United Kingdom.
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29
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McGaha TL, Karlsson MCI. Apoptotic cell responses in the splenic marginal zone: a paradigm for immunologic reactions to apoptotic antigens with implications for autoimmunity. Immunol Rev 2016; 269:26-43. [PMID: 26683143 DOI: 10.1111/imr.12382] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Apoptotic cells drive innate regulatory responses that result in tolerogenic immunity. This is a critical aspect of cell physiology as apoptotic cells expose potentially dangerous nuclear antigens on the surface in apoptotic blebs, and failure in their recognition, phagocytosis, or destruction can cause dramatic autoimmunity in experimental models and is linked to development and progression of systemic pathology in human. The marginal zone is a specialized splenic environment that serves as a transitional site from circulation to peripheral lymphoid structures. The marginal zone serves a key role in trapping of particulates and initiation of innate responses against systemic microbial pathogens. However in recent years, it has become clear the marginal zone is also important for initiation of immune tolerance to apoptotic cells, driving a coordinated response involving multiple phagocyte and lymphocyte subsets. Recent reports linking defects in splenic macrophage function to systemic lupus erythematosus in a manner analogous to marginal zone macrophages in lupus-prone mice provide an impetus to better understand the mechanistic basis of the apoptotic cell response in the marginal zone and its general applicability to apoptotic cell-driven tolerance at other tissue sites. In this review, we discuss immune responses to apoptotic cells in the spleen in general and the marginal zone in particular, the relationship of these responses to autoimmune disease, and comparisons to apoptotic cell immunity in humans.
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Affiliation(s)
- Tracy L McGaha
- Department of Immunology, Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Princess Margaret Cancer Center, University Health Network, Toronto, ON, Canada
| | - Mikael C I Karlsson
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
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30
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Handa JT, Cano M, Wang L, Datta S, Liu T. Lipids, oxidized lipids, oxidation-specific epitopes, and Age-related Macular Degeneration. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:430-440. [PMID: 27480216 DOI: 10.1016/j.bbalip.2016.07.013] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 12/25/2022]
Abstract
Age-related Macular Degeneration (AMD) is the leading cause of blindness among the elderly in western societies. While antioxidant micronutrient treatment is available for intermediate non-neovascular disease, and effective anti-vascular endothelial growth factor treatment is available for neovascular disease, treatment for early AMD is lacking due to an incomplete understanding of the early molecular events. The role of lipids, which accumulate in the macula, and their oxidation, has emerged as an important factor in disease development. These oxidized lipids can either directly contribute to tissue injury or react with amine on proteins to form oxidation-specific epitopes, which can induce an innate immune response. If inadequately neutralized, the inflammatory response from these epitopes can incite tissue injury during disease development. This review explores how the accumulation of lipids, their oxidation, and the ensuing inflammatory response might contribute to the pathogenesis of AMD. This article is part of a Special Issue entitled: Lipid modification and lipid peroxidation products in innate immunity and inflammation edited by Christoph J. Binder .
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Affiliation(s)
- James T Handa
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21287, United States.
| | - Marisol Cano
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21287, United States.
| | - Lei Wang
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21287, United States.
| | - Sayantan Datta
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21287, United States.
| | - Tongyun Liu
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21287, United States.
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31
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Meri S. Self-nonself discrimination by the complement system. FEBS Lett 2016; 590:2418-34. [PMID: 27393384 DOI: 10.1002/1873-3468.12284] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 06/29/2016] [Accepted: 07/06/2016] [Indexed: 01/09/2023]
Abstract
The alternative pathway (AP) of complement can recognize nonself structures by only two molecules, C3b and factor H. The AP deposits C3b covalently on nonself structures via an amplification system. The actual discrimination is performed by factor H, which has binding sites for polyanions (sialic acids, glycosaminoglycans, phospholipids). This robust recognition of 'self' protects our own intact viable cells and tissues, while activating structures are recognized by default. Foreign targets are opsonized for phagocytosis or killed. Mutations in factor H predispose to severe diseases. In hemolytic uremic syndrome, they promote complement attack against blood cells and vascular endothelial cells and lead, for example, to kidney and brain damage. Even pathogens can exploit factor H. In fact, the ability to bind factor H discriminates most pathogenic microbes from nonpathogenic ones.
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Affiliation(s)
- Seppo Meri
- Immunobiology, Research Programs Unit, Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Finland.,HUSLAB, Helsinki University Hospital, Finland.,Humanitas University, Milan, Italy
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32
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Abstract
Ageing, infections and inflammation result in oxidative stress that can irreversibly damage cellular structures. The oxidative damage of lipids in membranes or lipoproteins is one of these deleterious consequences that not only alters lipid function but also leads to the formation of neo-self epitopes - oxidation-specific epitopes (OSEs) - which are present on dying cells and damaged proteins. OSEs represent endogenous damage-associated molecular patterns that are recognized by pattern recognition receptors and the proteins of the innate immune system, and thereby enable the host to sense and remove dangerous biological waste and to maintain homeostasis. If this system is dysfunctional or overwhelmed, the accumulation of OSEs can trigger chronic inflammation and the development of diseases, such as atherosclerosis and age-related macular degeneration. Understanding the molecular components and mechanisms that are involved in this process will help to identify individuals with an increased risk of developing chronic inflammation, and will also help to indicate novel modes of therapeutic intervention.
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33
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Colonna L, Parry GC, Panicker S, Elkon KB. Uncoupling complement C1s activation from C1q binding in apoptotic cell phagocytosis and immunosuppressive capacity. Clin Immunol 2016; 163:84-90. [PMID: 26769276 DOI: 10.1016/j.clim.2015.12.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 12/30/2015] [Accepted: 12/31/2015] [Indexed: 12/19/2022]
Abstract
Complement activation contributes to inflammation in many diseases, yet it also supports physiologic apoptotic cells (AC) clearance and its downstream immunosuppressive effects. The roles of individual complement components in AC phagocytosis have been difficult to dissect with artificially depleted sera. Using human in vitro systems and the novel antibody complement C1s inhibitor TNT003, we uncoupled the role of the enzymatic activation of the classical pathway from the opsonizing role of C1q in mediating a) the phagocytosis of early and late AC, and b) the immunosuppressive capacity of early AC. We found that C1s inhibition had a small impact on the physiologic clearance of early AC, leaving their immunosuppressive properties entirely unaffected, while mainly inhibiting the phagocytosis of late apoptotic/secondary necrotic cells. Our data suggest that C1s inhibition may represent a valuable therapeutic strategy to control classical pathway activation without causing significant AC accumulation in diseases without defects in AC phagocytosis.
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Affiliation(s)
- Lucrezia Colonna
- University of Washington, Division of Rheumatology, 750 Republican Street, Box 358060, Seattle, WA 98109, USA.
| | - Graham C Parry
- True North Therapeutics, Inc, 951 Gateway Blvd, South San Francisco, CA 94080, USA.
| | - Sandip Panicker
- True North Therapeutics, Inc, 951 Gateway Blvd, South San Francisco, CA 94080, USA.
| | - Keith B Elkon
- University of Washington, Division of Rheumatology, 750 Republican Street, Box 358060, Seattle, WA 98109, USA.
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Merle NS, Noe R, Halbwachs-Mecarelli L, Fremeaux-Bacchi V, Roumenina LT. Complement System Part II: Role in Immunity. Front Immunol 2015; 6:257. [PMID: 26074922 PMCID: PMC4443744 DOI: 10.3389/fimmu.2015.00257] [Citation(s) in RCA: 655] [Impact Index Per Article: 72.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 05/09/2015] [Indexed: 12/14/2022] Open
Abstract
The complement system has been considered for a long time as a simple lytic cascade, aimed to kill bacteria infecting the host organism. Nowadays, this vision has changed and it is well accepted that complement is a complex innate immune surveillance system, playing a key role in host homeostasis, inflammation, and in the defense against pathogens. This review discusses recent advances in the understanding of the role of complement in physiology and pathology. It starts with a description of complement contribution to the normal physiology (homeostasis) of a healthy organism, including the silent clearance of apoptotic cells and maintenance of cell survival. In pathology, complement can be a friend or a foe. It acts as a friend in the defense against pathogens, by inducing opsonization and a direct killing by C5b–9 membrane attack complex and by triggering inflammatory responses with the anaphylatoxins C3a and C5a. Opsonization plays also a major role in the mounting of an adaptive immune response, involving antigen presenting cells, T-, and B-lymphocytes. Nevertheless, it can be also an enemy, when pathogens hijack complement regulators to protect themselves from the immune system. Inadequate complement activation becomes a disease cause, as in atypical hemolytic uremic syndrome, C3 glomerulopathies, and systemic lupus erythematosus. Age-related macular degeneration and cancer will be described as examples showing that complement contributes to a large variety of conditions, far exceeding the classical examples of diseases associated with complement deficiencies. Finally, we discuss complement as a therapeutic target.
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Affiliation(s)
- Nicolas S Merle
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France
| | - Remi Noe
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France ; Ecole Pratique des Hautes Études (EPHE) , Paris , France
| | - Lise Halbwachs-Mecarelli
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France
| | - Veronique Fremeaux-Bacchi
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France ; Service d'Immunologie Biologique, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou , Paris , France
| | - Lubka T Roumenina
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France
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Abstract
PURPOSE OF REVIEW Systemic lupus erythematosus (SLE) is characterized by autoantibodies directed against nuclear autoantigens normally concealed from immune recognition in healthy individuals. Here, we summarize recently identified mechanisms of abnormal cell death leading to exposure and aberrant processing of nucleoprotein self antigens, and discuss their role in the SLE pathogenesis. RECENT FINDINGS During the past few years, the unveiling of several new forms of cell death has expanded our understanding beyond the simple view of 'apoptotic' versus 'necrotic' cell death. SLE patients show abnormalities in cell death at several levels, including increased rates of apoptosis, necrosis, and autophagy, as well as reduced clearance of dying cells. These abnormalities lead to an increased autoantigen burden and antigen modifications, such as nucleic acid oxidation that increases the inflammatory properties of self antigens. Recent investigations have highlighted the role of opsonins in determining the immunogenic versus tolerogenic characteristics of self antigens. SUMMARY Dysregulation of different forms of programmed cell death contributes to increased exposure, availability, and immunogenic characteristics of intracellular self antigens, which all participate in development of lupus autoimmunity. As our understanding of abnormalities of cell death in SLE advances, potential therapeutic opportunities await human implementation.
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Grau A, Tabib A, Grau I, Reiner I, Mevorach D. Apoptotic cells induce NF-κB and inflammasome negative signaling. PLoS One 2015; 10:e0122440. [PMID: 25822487 PMCID: PMC4379019 DOI: 10.1371/journal.pone.0122440] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Accepted: 02/21/2015] [Indexed: 11/29/2022] Open
Abstract
As they undergo phagocytosis, most early apoptotic cells negatively regulate proinflammatory signaling and were suggested as a major mechanism in the resolution of inflammation. The dextran sulfate sodium model is generally viewed as an epithelial damage model suited to investigate innate immune responses. Macrophages primed with LPS and subsequently exposed to DSS secrete high levels of IL-1β in an NLRP3-, ASC-, and caspase-1-dependent manner. The aim of this research was to test the therapeutic effect of a single dose of apoptotic cells in a DSS-colitis model and to explore possible mechanisms. Primary peritoneal macrophages, the DSS mice model, and Nlrp3-deficient mice, were used to assess the effect apoptotic cells on colitis. Immunohistochemistry, flow-cytometer, and western blots helped to explore the effect and mechanisms. Using a variety of NLRP3 triggering mechanisms, we show that apoptotic cells negatively regulate NF-κB and NLRP3 activation in primary peritoneal macrophages, at pre- and post-transcription levels, via inhibition of reactive oxygen species, lysosomal stabilization, and blocking K+ efflux. This property of apoptotic cells is demonstrated in a dramatic clinical, histological, and immunological amelioration of DSS colitis in Balb/c and B6 mice following a single administration of apoptotic cells.
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Affiliation(s)
- Amir Grau
- The Laboratory for Cellular and Molecular Immunology, Rheumatology Research Center, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Adi Tabib
- The Laboratory for Cellular and Molecular Immunology, Rheumatology Research Center, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Inna Grau
- The Laboratory for Cellular and Molecular Immunology, Rheumatology Research Center, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Inna Reiner
- The Laboratory for Cellular and Molecular Immunology, Rheumatology Research Center, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Dror Mevorach
- The Laboratory for Cellular and Molecular Immunology, Rheumatology Research Center, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
- * E-mail:
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37
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Price PJR, Bánki Z, Scheideler A, Stoiber H, Verschoor A, Sutter G, Lehmann MH. Complement component C5 recruits neutrophils in the absence of C3 during respiratory infection with modified vaccinia virus Ankara. THE JOURNAL OF IMMUNOLOGY 2014; 194:1164-8. [PMID: 25548218 DOI: 10.4049/jimmunol.1301410] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Efficient leukocyte migration is important for an effective host response to viral infection and the development of adaptive immunity. The poxvirus strain modified vaccinia virus Ankara (MVA), a safe and efficient viral vector, rapidly induces chemokine expression and respiratory recruitment of leukocytes, which is unique among vaccinia viruses. In addition to chemokines, the complement system contributes to the attraction and activation of different types of leukocytes. Using a murine model of intranasal infection, we show in this study that MVA-induced neutrophil recruitment depends on complement component C5. Remarkably, we find that C5 mediates neutrophil recruitment to the lung, even in the absence of the central complement component C3. Our findings argue for complement C5 activation during MVA infection of the lung via a C3-independent pathway, which enables rapid recruitment of neutrophils.
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Affiliation(s)
- Philip J R Price
- Institut für Infektionsmedizin und Zoonosen, Ludwig-Maximilians-Universität München, Munich 80539, Germany; German Centre for Infection Research, Partner Site Munich, Munich 80539, Germany
| | - Zoltán Bánki
- Division of Virology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Angelika Scheideler
- Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt, Abteilung für Vergleichende Medizin, Neuherberg 85764, Germany; and
| | - Heribert Stoiber
- Division of Virology, Medical University of Innsbruck, Innsbruck 6020, Austria
| | - Admar Verschoor
- Institut für Medizinische Mikrobiologie, Immunologie und Hygiene, Technische Universität München, Munich 81675, Germany
| | - Gerd Sutter
- Institut für Infektionsmedizin und Zoonosen, Ludwig-Maximilians-Universität München, Munich 80539, Germany; German Centre for Infection Research, Partner Site Munich, Munich 80539, Germany
| | - Michael H Lehmann
- Institut für Infektionsmedizin und Zoonosen, Ludwig-Maximilians-Universität München, Munich 80539, Germany; German Centre for Infection Research, Partner Site Munich, Munich 80539, Germany;
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Ellegård R, Crisci E, Burgener A, Sjöwall C, Birse K, Westmacott G, Hinkula J, Lifson JD, Larsson M. Complement opsonization of HIV-1 results in decreased antiviral and inflammatory responses in immature dendritic cells via CR3. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2014; 193:4590-601. [PMID: 25252956 PMCID: PMC4201991 DOI: 10.4049/jimmunol.1401781] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Accepted: 08/25/2014] [Indexed: 11/19/2022]
Abstract
Immature dendritic cells (iDCs) in genital and rectal mucosa may be one of the first cells to come into contact with HIV-1 during sexual transmission of virus. HIV-1 activates the host complement system, which results in opsonization of virus by inactivated complement fragments, for example, iC3b. We investigated antiviral and inflammatory responses induced in human iDCs after exposure to free HIV-1 (F-HIV), complement-opsonized HIV-1 (C-HIV), and complement and Ab-opsonized HIV-1 (CI-HIV). F-HIV gave rise to a significantly higher expression of antiviral factors such as IFN-β, myxovirus resistance protein A, and IFN-stimulated genes, compared with C-HIV and CI-HIV. Additionally, F-HIV induced inflammatory factors such as IL-1β, IL-6, and TNF-α, whereas these responses were weakened or absent after C-HIV or CI-HIV exposure. The responses induced by F-HIV were TLR8-dependent with subsequent activation of IFN regulatory factor 1, p38, ERK, PI3K, and NF-κB pathways, whereas these responses were not induced by C-HIV, which instead induced activation of IFN regulatory factor 3 and Lyn. This modulation of TLR8 signaling was mediated by complement receptor 3 and led to enhanced infection. The impact that viral hijacking of the complement system has on iDC function could be an important immune evasion mechanism used by HIV-1 to establish infection in the host.
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Affiliation(s)
- Rada Ellegård
- Division of Molecular Virology, Department of Clinical and Experimental Medicine, Linköping University, 581 85 Linköping, Sweden
| | - Elisa Crisci
- Division of Molecular Virology, Department of Clinical and Experimental Medicine, Linköping University, 581 85 Linköping, Sweden
| | - Adam Burgener
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada; National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba R3E 3R2, Canada
| | - Christopher Sjöwall
- Division of Rheumatology/Autoimmunity and Immune Regulation Unit, Department of Clinical and Experimental Medicine, Linköping University, 581 85 Linköping, Sweden; and
| | - Kenzie Birse
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada; National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba R3E 3R2, Canada
| | - Garrett Westmacott
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba R3E 3R2, Canada
| | - Jorma Hinkula
- Division of Molecular Virology, Department of Clinical and Experimental Medicine, Linköping University, 581 85 Linköping, Sweden
| | - Jeffrey D Lifson
- Leidos Biomedical Research, Inc., Frederick National Laboratory, Frederick, MD 21702
| | - Marie Larsson
- Division of Molecular Virology, Department of Clinical and Experimental Medicine, Linköping University, 581 85 Linköping, Sweden;
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Smolny M, Rogers ML, Shafton A, Rush RA, Stebbing MJ. Development of non-viral vehicles for targeted gene transfer into microglia via the integrin receptor CD11b. Front Mol Neurosci 2014; 7:79. [PMID: 25346658 PMCID: PMC4191133 DOI: 10.3389/fnmol.2014.00079] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 09/16/2014] [Indexed: 12/12/2022] Open
Abstract
Microglial activation is a central event in neurodegeneration. Novel technologies are sought for that specifically manipulate microglial function in order to delineate their role in onset and progression of neuropathologies. We investigated for the first time whether non-viral gene delivery based on polyethyleneglycol-polyethyleneimine conjugated to the monoclonal anti-CD11b antibody OX42 ("OX42-immunogene") could be used to specifically target microglia. We first conducted immunofluorescence studies with the OX42 antibody and identified its microglial integrin receptor CD11b as a potential target for receptor-mediated gene transfer based on its cellular specificity in mixed glia culture and in vivo and found that the OX42 antibody is rapidly internalized and trafficked to acidic organelles in absence of activation of the respiratory burst. We then performed transfection experiments with the OX42-immunogene in vitro and in rat brain showing that the OX42-immunogene although internalized was degraded intracellularly and did not cause substantial gene expression in microglia. Investigation of specific barriers to microglial gene transfer revealed that aggregated OX42-immunogene polyplexes stimulated the respiratory burst that likely involved Fcγ-receptors. Transfections in the presence of the endosomolytic agent chloroquine improved transfection efficiency indicating that endosomal escape may be limited. This study identifies CD11b as an entry point for antibody-mediated gene transfer into microglia and takes important steps toward the further development of OX42-immunogenes.
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Affiliation(s)
- Markus Smolny
- School of Medical Sciences and Health Innovations Research Institute, Royal Melbourne Institute of Technology UniversityBundoora, VIC, Australia
| | - Mary-Louise Rogers
- Department of Human Physiology, Centre for Neuroscience, Flinders UniversityAdelaide, SA, Australia
| | - Anthony Shafton
- The Florey Institute of Neuroscience and Mental Health, The University of MelbourneParkville, VIC, Australia
| | - Robert A. Rush
- Department of Human Physiology, Centre for Neuroscience, Flinders UniversityAdelaide, SA, Australia
| | - Martin J. Stebbing
- School of Medical Sciences and Health Innovations Research Institute, Royal Melbourne Institute of Technology UniversityBundoora, VIC, Australia
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Clarke EV, Tenner AJ. Complement modulation of T cell immune responses during homeostasis and disease. J Leukoc Biol 2014; 96:745-56. [PMID: 25210145 DOI: 10.1189/jlb.3mr0214-109r] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The complement system is an ancient and critical effector mechanism of the innate immune system as it senses, kills, and clears infectious and/or dangerous particles and alerts the immune system to the presence of the infection and/or danger. Interestingly, an increasing number of reports have demonstrated a clear role for complement in the adaptive immune system as well. Of note, a number of recent studies have identified previously unknown roles for complement proteins, receptors, and regulators in T cell function. Here, we will review recent data demonstrating the influence of complement proteins C1q, C3b/iC3b, C3a (and C3aR), and C5a (and C5aR) and complement regulators DAF (CD55) and CD46 (MCP) on T cell function during homeostasis and disease. Although new concepts are beginning to emerge in the field of complement regulation of T cell function, future experiments should focus on whether complement is interacting directly with the T cell or is having an indirect effect on T cell function via APCs, the cytokine milieu, or downstream complement activation products. Importantly, the identification of the pivotal molecular pathways in the human systems will be beneficial in the translation of concepts derived from model systems to therapeutic targeting for treatment of human disorders.
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Affiliation(s)
- Elizabeth V Clarke
- Department of Molecular Biology and Biochemistry and Institute for Immunology, University of California, Irvine, California, USA
| | - Andrea J Tenner
- Department of Molecular Biology and Biochemistry and Institute for Immunology, University of California, Irvine, California, USA
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Abstract
Insights into the important contribution of inflammation and immune functions in the development and progression of atherosclerosis have greatly improved our understanding of this disease. Although the role of T cells has been extensively studied for decades, only recently has the role of B cells gained more attention. Recent studies have identified differential effects of different B-cell subsets and helped to clarify the still poorly understood mechanisms by which these act. B1 cells have been shown to prevent lesion formation, whereas B2 cells have been suggested to promote it. Natural IgM antibodies, mainly derived from B1 cells, have been shown to mediate atheroprotective effects, but the functional role of other immunoglobulin classes, particularly IgG, still remains elusive. In this review, we will focus on recent insights on the role of B cells and various immunoglobulin classes and how these may mediate their effects in atherosclerotic lesion formation. Moreover, we will highlight potential therapeutic approaches focusing on B-cell depletion that could be used to translate experimental evidence to human disease.
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Affiliation(s)
- Dimitrios Tsiantoulas
- From the Center for Molecular Medicine (CeMM) of the Austrian Academy of Sciences, Vienna, Austria (D.T., C.J.B.); Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (D.T., C.J.B.); and Department of Medicine, University of California San Diego, La Jolla (C.J.D., J.L.W.)
| | - Cody J Diehl
- From the Center for Molecular Medicine (CeMM) of the Austrian Academy of Sciences, Vienna, Austria (D.T., C.J.B.); Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (D.T., C.J.B.); and Department of Medicine, University of California San Diego, La Jolla (C.J.D., J.L.W.)
| | - Joseph L Witztum
- From the Center for Molecular Medicine (CeMM) of the Austrian Academy of Sciences, Vienna, Austria (D.T., C.J.B.); Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (D.T., C.J.B.); and Department of Medicine, University of California San Diego, La Jolla (C.J.D., J.L.W.)
| | - Christoph J Binder
- From the Center for Molecular Medicine (CeMM) of the Austrian Academy of Sciences, Vienna, Austria (D.T., C.J.B.); Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (D.T., C.J.B.); and Department of Medicine, University of California San Diego, La Jolla (C.J.D., J.L.W.).
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Wang L, Kondo N, Cano M, Ebrahimi K, Yoshida T, Barnett BP, Biswal S, Handa JT. Nrf2 signaling modulates cigarette smoke-induced complement activation in retinal pigmented epithelial cells. Free Radic Biol Med 2014; 70:155-66. [PMID: 24440594 PMCID: PMC4006310 DOI: 10.1016/j.freeradbiomed.2014.01.015] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 12/31/2013] [Accepted: 01/09/2014] [Indexed: 12/21/2022]
Abstract
Whereas cigarette smoking (CS) and dysregulated complement are thought to play central roles in age-related macular degeneration (AMD), their exact roles are unknown. The aim of this study was to determine if CS activates complement and if the antioxidant transcription factor Nrf2 modulates this response. In AMD specimens, Nrf2 immunolabeling was strong in the cytoplasm, with scattered nuclear labeling of macular retinal pigmented epithelial (RPE) cells that appeared normal, but was decreased and without nuclear labeling in dysmorphic cells overlying drusen, a hallmark AMD lesion. Cigarette smoke extract (CSE) induced Nrf2 nuclear translocation in RPE cells with increased antioxidant and complement gene expression. Whereas CFH protein was not altered by CSE, the cell membrane regulator proteins CD46, CD55, and CD59 were decreased, and C3a and C3b, but not iC3b, were increased compared to controls. C5b-9 was increased by CSE, but at sublytic levels, only after addition of normal human serum. Nrf2 knockdown enhanced the increase in C3a and C3b from CSE, but not iC3b, C5a, or C5b-9. CSE also increased IL-1b expression and secretion after C3a generation and was reduced by a C3aR antagonist. In contrast, the Nrf2 activator CDDO-Im restored complement gene expression in RPE cells exposed to CSE. We provide evidence of altered Nrf2 in human AMD and that CSE induces a proinflammatory environment specifically by generating C3a and C3b, and Nrf2 deficiency magnifies this specific complement response.
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Affiliation(s)
- Lei Wang
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Naoshi Kondo
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Marisol Cano
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Katayoon Ebrahimi
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Takeshi Yoshida
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Bradley P. Barnett
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Shyam Biswal
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - James T. Handa
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA
- Corresponding Author: James T. Handa, MD; Smith Building, Room 3015, 400 N. Broadway, Wilmer Eye Institute, Johns Hopkins School of Medicine, Johns Hopkins University, Baltimore, MD, USA. Tel: 410 614-421; Fax: 410 614-547;
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43
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Galectin-1 induces 12/15-lipoxygenase expression in murine macrophages and favors their conversion toward a pro-resolving phenotype. Prostaglandins Other Lipid Mediat 2013; 107:85-94. [DOI: 10.1016/j.prostaglandins.2013.08.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Revised: 08/01/2013] [Accepted: 08/06/2013] [Indexed: 02/05/2023]
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Mevorach D, Zuckerman T, Reiner I, Shimoni A, Samuel S, Nagler A, Rowe JM, Or R. Single infusion of donor mononuclear early apoptotic cells as prophylaxis for graft-versus-host disease in myeloablative HLA-matched allogeneic bone marrow transplantation: a phase I/IIa clinical trial. Biol Blood Marrow Transplant 2013; 20:58-65. [PMID: 24140121 DOI: 10.1016/j.bbmt.2013.10.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 10/08/2013] [Indexed: 12/20/2022]
Abstract
Because of its potent immunomodulatory effect, an infusion of donor mononuclear early apoptotic cells (ApoCell) was tested in addition to cyclosporine and methotrexate as prophylaxis for acute graft-versus-host disease (GVHD) after HLA-matched myeloablative allogeneic hematopoietic stem cell transplantation (HSCT) from a related donor. In a phase I/IIa clinical trial, we treated 13 patients (median age, 37 years; range, 20 to 59 years) with hematologic malignancies: 7 patients with acute lymphoblastic leukemia, 5 patients with acute myeloid leukemia, and 1 patient with chronic myeloid leukemia, who received conventional myeloablative conditioning, with 35, 70, 140, or 210 × 10(6) cell/kg of donor ApoCell, on day -1 of transplantation. Engraftment was successful in all patients with median time to neutrophil recovery of 13 days (range, 11 to 19), and platelet recovery of 15 days (range, 11 to 59). Serious adverse effects were reported on 10 occasions in the trial, all of which were considered unrelated (n = 7) or unlikely to be related (n = 3) to ApoCell infusion. The nonrelapse mortality at day 100 and 180 after transplantation was 7.7% and the overall survival at 100 and 180 days after transplantation was 92% and 85%, respectively. All ApoCell preparations showed an in vitro significant tolerogenic effect upon interaction with dendritic cells. The overall incidence of acute grades II to IV GVHD was 23%, whereas among those receiving the 2 higher doses (n = 6), the rate was 0%. These results suggest that a single infusion of donor ApoCell in HLA-matched allogeneic HSCT is a safe and potentially effective prophylaxis for acute GVHD occurring after myeloablative conditioning. No dose limiting toxicity was observed. (Clinicaltrials.gov no. NCT00524784).
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Affiliation(s)
- Dror Mevorach
- The Rheumatology Research Center, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
| | - Tsila Zuckerman
- Department of Hematology and Bone Marrow Transplantation, Rambam Medical Center, Haifa, Israel
| | - Inna Reiner
- The Rheumatology Research Center, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Avichai Shimoni
- Division of Hematology and Bone Marrow Transplantation, Chaim Sheba Medical Center, Tel-Hashomer, Israel
| | - Simcha Samuel
- Department of Bone Marrow Transplantation and Cancer Immunotherapy, Hadassah University Medical Center, Jerusalem, Israel
| | - Arnon Nagler
- Division of Hematology and Bone Marrow Transplantation, Chaim Sheba Medical Center, Tel-Hashomer, Israel
| | - Jacob M Rowe
- Department of Hematology, Shaare Zedek, Jerusalem, Israel
| | - Reuven Or
- Department of Bone Marrow Transplantation and Cancer Immunotherapy, Hadassah University Medical Center, Jerusalem, Israel
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45
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Barnett BP, Handa JT. Retinal microenvironment imbalance in dry age-related macular degeneration: a mini-review. Gerontology 2013; 59:297-306. [PMID: 23406680 DOI: 10.1159/000346169] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 11/29/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Age-related macular degeneration (AMD) is the leading cause of blindness in the western world. To prevent what will certainly be a tremendous health and economic burden, effective therapeutics for AMD are urgently needed. To develop these agents in a timely fashion, the molecular pathways that cause disease progression must be elucidated. OBJECTIVE To briefly describe the clinical features of AMD, and review the current understanding of the molecular basis of AMD. METHODS A literature review. RESULTS The discussion will primarily focus on the interplay of oxidative stress and complement dysregulation and the resulting chronic proinflammatory state thought to be central in AMD pathogenesis. CONCLUSIONS Oxidative stress and complement dysregulation play a substantive role in the development of AMD.
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Affiliation(s)
- Brad P Barnett
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA
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46
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Ariel A, Timor O. Hanging in the balance: endogenous anti-inflammatory mechanisms in tissue repair and fibrosis. J Pathol 2012; 229:250-63. [DOI: 10.1002/path.4108] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 09/05/2012] [Accepted: 09/12/2012] [Indexed: 02/06/2023]
Affiliation(s)
- Amiram Ariel
- Department of Biology, Faculty of Natural Sciences; University of Haifa; Haifa Israel
| | - Orly Timor
- Department of Biology, Faculty of Natural Sciences; University of Haifa; Haifa Israel
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Zhong K, Song W, Wang Q, Wang C, Liu X, Chen D, Zhu Z, Wu Y, Zhang W, Zhang M. Murine myeloid dendritic cells that phagocytose apoptotic T cells inhibit the immune response via NO. PLoS One 2012; 7:e49378. [PMID: 23166651 PMCID: PMC3499560 DOI: 10.1371/journal.pone.0049378] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 10/09/2012] [Indexed: 01/14/2023] Open
Abstract
The contraction phase of antigen-specific immune responses involves the apoptotic loss of numerous activated lymphocytes. While apoptotic cells are known to induce immune suppression, the mechanisms involved therein are still ambiguous. Some reports have speculated that macrophages can induce regulatory T cells (Tregs) after engulfing apoptotic cells. In this study, we showed that dendritic cells (DCs) that phagocytose apoptotic T cells acquire inhibitory function (named DCapos) toward CD4+ and CD8+ T cells. These inhibitory DCs could not induce the generation of Tregs, but they were found to directly inhibit mDCs that initiate CD4+ and CD8+ T cell proliferation both in vitro and in vivo. Soluble factors including NO play a role in the DCapos-induced suppression of CD4+ and CD8+ T cell proliferation. Further results showed that STAT3 phosphorylation and inducible nitric oxide synthase (iNOS) generation were enhanced when DCs were co-cultured with apoptotic cells. Both iNOS transcription and NO secretion were inhibited in the presence of the specific p-STAT3 inhibitor JSI-124. All the data indicated that apoptotic cells could turn DCs to inhibitory DCs, which might play important roles in the suppression of immune responses. STAT3 activation and the consequent release of NO are responsible for the inhibitory functions of DCapos.
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Affiliation(s)
- Kaili Zhong
- Department of Lymphoma, Affiliated Hospital of Academy of Military Medical Sciences, Beijing, People’s Republic of China
| | - Wengang Song
- Department of Immunology, Taishan Medical College, Tai’an, Shandong Province, People’s Republic of China
| | - Qian Wang
- Department of Immunology, Taishan Medical College, Tai’an, Shandong Province, People’s Republic of China
| | - Chao Wang
- Institute of Immunology, School of Medicine, Tsinghua University, Beijing, People’s Republic of China
| | - Xi Liu
- Institute of Immunology, School of Medicine, Tsinghua University, Beijing, People’s Republic of China
| | - Dongwei Chen
- Institute of Immunology, School of Medicine, Tsinghua University, Beijing, People’s Republic of China
| | - Zhongli Zhu
- Department of Immunology, Taishan Medical College, Tai’an, Shandong Province, People’s Republic of China
| | - Yiqing Wu
- Institute of Immunology, School of Medicine, Tsinghua University, Beijing, People’s Republic of China
| | - Weijing Zhang
- Department of Lymphoma, Affiliated Hospital of Academy of Military Medical Sciences, Beijing, People’s Republic of China
- * E-mail: (WZ); (MZ)
| | - Minghui Zhang
- Institute of Immunology, School of Medicine, Tsinghua University, Beijing, People’s Republic of China
- * E-mail: (WZ); (MZ)
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Ferenbach DA, Sheldrake TA, Dhaliwal K, Kipari TMJ, Marson LP, Kluth DC, Hughes J. Macrophage/monocyte depletion by clodronate, but not diphtheria toxin, improves renal ischemia/reperfusion injury in mice. Kidney Int 2012; 82:928-33. [PMID: 22673886 DOI: 10.1038/ki.2012.207] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The role of resident renal mononuclear phagocytes in acute kidney injury is controversial with experimental data suggesting both deleterious and protective functions. To help resolve this, we used mice transgenic for the human diphtheria toxin receptor under the control of the CD11b promoter and treated them with diphtheria toxin, or liposomal clodronate, or both to deplete monocyte/mononuclear phagocytes prior to renal ischemia/reperfusion injury. Although either system effectively depleted circulating monocytes and resident mononuclear phagocytes, depletion was most marked in diphtheria toxin-treated mice. Despite this, diphtheria toxin treatment did not protect from renal ischemia. In contrast, mice treated with clodronate exhibited reduced renal failure and acute tubular necrosis, suggesting key differences between these depletion strategies. Clodronate did not deplete CD206-positive renal macrophages and, unlike diphtheria toxin, left resident CD11c-positive cells unscathed while inducing dramatic apoptosis in hepatic and splenic mononuclear phagocyte populations. Abolition of the protected phenotype by administration of diphtheria toxin to clodronate-treated mice suggested that the protective effect of clodronate resulted from the presence of a cytoprotective intrarenal population of mononuclear phagocytes sensitive to diphtheria toxin-mediated ablation.
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Affiliation(s)
- David A Ferenbach
- MRC Centre for Inflammation Research, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK.
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Handa JT. How does the macula protect itself from oxidative stress? Mol Aspects Med 2012; 33:418-35. [PMID: 22503691 DOI: 10.1016/j.mam.2012.03.006] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 03/30/2012] [Indexed: 02/07/2023]
Abstract
Oxidative stress has been hypothesized to contribute to the development of age-related macular degeneration (AMD), the most common cause of blindness in the United States. At present, there is no treatment for early disease. Reactive oxygen species (ROS) play a physiological role in the retinal pigment epithelium (RPE), a key cell type in this disease, but with excessive ROS, oxidative damage or excessive innate immune system activation can result. The RPE has developed a robust antioxidant system driven by the transcription factor Nrf2. Impaired Nrf2 signaling can lead to oxidative damage or activate the innate immune response, both of which can lead to RPE apoptosis, a defining change in AMD. Several mouse models simulating environmental stressors or targeting specific antioxidant enzymes such as superoxide dismutase or Nrf2, have simulated some of the features of AMD. While ROS are short-lived, oxidatively damaged molecules termed oxidation specific epitopes (OSEs), can be long-lived and a source of chronic stress that activates the innate immune system through pattern recognition receptors (PRRs). The macula accumulates a number of OSEs including carboxyethylpyrrole, malondialdehyde, 4-hydroxynonenal, and advanced glycation endproducts, as well as their respective neutralizing PRRs. Excessive accumulation of OSEs results in pathologic immune activation. For example, mice immunized with the carboxyethylpyrrole develop cardinal features of AMD. Regulating ROS in the RPE by modulating antioxidant systems or neutralizing OSEs through an appropriate innate immune response are potential modalities to treat or prevent early AMD.
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Affiliation(s)
- James T Handa
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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50
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Cheung WY, Simmons CA, You L. Osteocyte apoptosis regulates osteoclast precursor adhesion via osteocytic IL-6 secretion and endothelial ICAM-1 expression. Bone 2012; 50:104-10. [PMID: 21986000 DOI: 10.1016/j.bone.2011.09.052] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 09/18/2011] [Accepted: 09/25/2011] [Indexed: 11/25/2022]
Abstract
Osteocyte apoptosis precedes osteoclast resorption, and may act as a critical signal to trigger bone remodeling. While osteoclast precursors are known to travel via the circulation, the specific mechanisms by which they accumulate at remodeling sites are unclear. We hypothesized that osteocyte apoptosis mediates osteoclast precursor adhesion to vascular endothelium by regulating osteocytic secretion of IL-6 and soluble IL-6 receptor (sIL-6R) to promote endothelial ICAM-1 expression. We found that conditioned media from TNF-α-induced apoptotic MLO-Y4 osteocytes promoted RAW264.7 osteoclast precursor adhesion onto D4T endothelial cells (P<0.05). Blocking osteocyte apoptosis with a pan-caspase inhibitor (ZVAD-FMK) reduced osteoclast precursor adhesion to baseline levels (P<0.001). Endothelial cells treated with apoptotic osteocyte conditioned media had elevated surface expression of ICAM-1 (P<0.05), and blocking ICAM-1 abolished apoptosis-induced osteoclast precursor adhesion. Apoptotic osteocyte conditioned media contained more IL-6 (P<0.05) and sIL-6R (P<0.05) than non-apoptotic osteocyte conditioned media. When added exogenously, both IL-6 and sIL-6R were required for endothelial activation, and blocking IL-6 reduced apoptosis-induced osteoclast precursor adhesion to baseline levels (P<0.05). Therefore, we conclude that osteocyte apoptosis can promote osteoclast precursor adhesion to endothelial cells via ICAM-1; this is likely through increased osteocytic IL-6 and sIL-6R secretion, both of which are indispensible to endothelial activation.
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Affiliation(s)
- Wing-Yee Cheung
- Institute of Biomaterials & Biomedical Engineering, 164 College Street, Room 407, University of Toronto, Toronto, Ontario M5S 3G9.
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