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Liang X, Xiong X, Cao Y, Li Z, Chen J, Jiao Y, Deng Y, Du X. Globular C1q domain-containing protein from Pinctada fucata martensii participates in the immune defense process. FISH & SHELLFISH IMMUNOLOGY 2022; 123:521-527. [PMID: 35364260 DOI: 10.1016/j.fsi.2022.02.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/16/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
The globular C1q domain-containing (C1qDC) protein can recognize a variety of ligands, such as pathogen-associated molecular patterns, and plays an important role in the innate immune response. Our previous studies showed that a novel globular C1q domain-containing protein (PmC1qDC-1) is involved in the damage repair process of pearl oyster shells. However, the function of PmC1qDC-1 in pearl oyster innate immunity remains unknown. In the present study, the high-level structural analysis showed that PmC1qDC-1 was a spherical structure composed of 10 strands and was similar to the AiC1qDC-2 of bay scallop (Argopecten irradians). In situ hybridization indicated that PmC1qDC-1 had strong fluorescence signal in gills. Furthermore, the mRNA expression of PmC1qDC-1 was highly induced at 6-48 h in gill after lipopolysaccharide, peptidoglycan and polyinosinic-polycytidylic acid stimulation. Additionally, we obtained the recombinant protein of PmC1qDC-1 (rPmC1qDC-1) and found that rPmC1qDC-1 had antibacterial activity against Gram-negative (i.e., Pseudomonas aeruginosa, Vibrio parahaemolyticus, Escherichia coli, and Aeromonas hydrophila) and Gram-positive (i.e., Staphylococcus aureus and Bacillus subtilis) bacteria. These results indicated that PmC1qDC-1 might play an important role in the immune response against bacteria and viruses. This study provides clues for further studying the immune defense of Pinctada fucata martensii against pathogens and exploring the evolution of the classic pathway of complement system.
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Affiliation(s)
- Xueru Liang
- Fishery College, Guangdong Ocean University, Zhanjiang, 524025, China
| | - Xinwei Xiong
- Fishery College, Guangdong Ocean University, Zhanjiang, 524025, China
| | - Yanfei Cao
- Fishery College, Guangdong Ocean University, Zhanjiang, 524025, China
| | - Zhixin Li
- Fishery College, Guangdong Ocean University, Zhanjiang, 524025, China
| | - Jiayi Chen
- Fishery College, Guangdong Ocean University, Zhanjiang, 524025, China
| | - Yu Jiao
- Fishery College, Guangdong Ocean University, Zhanjiang, 524025, China; Pearl Breeding and Processing Engineering Technology Research Centre of Guangdong Province, Zhanjiang, 524088, China; Guangdong Science and Innovation Center for Pearl Culture, Zhanjiang, 524088, China
| | - Yuewen Deng
- Fishery College, Guangdong Ocean University, Zhanjiang, 524025, China; Pearl Breeding and Processing Engineering Technology Research Centre of Guangdong Province, Zhanjiang, 524088, China; Guangdong Science and Innovation Center for Pearl Culture, Zhanjiang, 524088, China; Guangdong Provincial Key Laboratory of Pathogenic Biology and Epidemiology for Aquatic Economic Animals, Zhanjiang, 524088, China
| | - Xiaodong Du
- Fishery College, Guangdong Ocean University, Zhanjiang, 524025, China; Pearl Breeding and Processing Engineering Technology Research Centre of Guangdong Province, Zhanjiang, 524088, China; Guangdong Science and Innovation Center for Pearl Culture, Zhanjiang, 524088, China.
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2
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Syed I, Wooten RM. Interactions Between Pathogenic Burkholderia and the Complement System: A Review of Potential Immune Evasion Mechanisms. Front Cell Infect Microbiol 2021; 11:701362. [PMID: 34660335 PMCID: PMC8515183 DOI: 10.3389/fcimb.2021.701362] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 09/15/2021] [Indexed: 12/12/2022] Open
Abstract
The genus Burkholderia contains over 80 different Gram-negative species including both plant and human pathogens, the latter of which can be classified into one of two groups: the Burkholderia pseudomallei complex (Bpc) or the Burkholderia cepacia complex (Bcc). Bpc pathogens Burkholderia pseudomallei and Burkholderia mallei are highly virulent, and both have considerable potential for use as Tier 1 bioterrorism agents; thus there is great interest in the development of novel vaccines and therapeutics for the prevention and treatment of these infections. While Bcc pathogens Burkholderia cenocepacia, Burkholderia multivorans, and Burkholderia cepacia are not considered bioterror threats, the incredible impact these infections have on the cystic fibrosis community inspires a similar demand for vaccines and therapeutics for the prevention and treatment of these infections as well. Understanding how these pathogens interact with and evade the host immune system will help uncover novel therapeutic targets within these organisms. Given the important role of the complement system in the clearance of bacterial pathogens, this arm of the immune response must be efficiently evaded for successful infection to occur. In this review, we will introduce the Burkholderia species to be discussed, followed by a summary of the complement system and known mechanisms by which pathogens interact with this critical system to evade clearance within the host. We will conclude with a review of literature relating to the interactions between the herein discussed Burkholderia species and the host complement system, with the goal of highlighting areas in this field that warrant further investigation.
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Affiliation(s)
- Irum Syed
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH, United States
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3
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Kovács RÁ, Vadászi H, Bulyáki É, Török G, Tóth V, Mátyás D, Kun J, Hunyadi-Gulyás É, Fedor FZ, Csincsi Á, Medzihradszky K, Homolya L, Juhász G, Kékesi KA, Józsi M, Györffy BA, Kardos J. Identification of Neuronal Pentraxins as Synaptic Binding Partners of C1q and the Involvement of NP1 in Synaptic Pruning in Adult Mice. Front Immunol 2021; 11:599771. [PMID: 33628204 PMCID: PMC7897678 DOI: 10.3389/fimmu.2020.599771] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 12/21/2020] [Indexed: 12/13/2022] Open
Abstract
Elements of the immune system particularly that of innate immunity, play important roles beyond their traditional tasks in host defense, including manifold roles in the nervous system. Complement-mediated synaptic pruning is essential in the developing and healthy functioning brain and becomes aberrant in neurodegenerative disorders. C1q, component of the classical complement pathway, plays a central role in tagging synapses for elimination; however, the underlying molecular mechanisms and interaction partners are mostly unknown. Neuronal pentraxins (NPs) are involved in synapse formation and plasticity, moreover, NP1 contributes to cell death and neurodegeneration under adverse conditions. Here, we investigated the potential interaction between C1q and NPs, and its role in microglial phagocytosis of synapses in adult mice. We verified in vitro that NPs interact with C1q, as well as activate the complement system. Flow cytometry, immunostaining and co-immunoprecipitation showed that synapse-bound C1q colocalizes and interacts with NPs. High-resolution confocal microscopy revealed that microglia-surrounded C1q-tagged synapses are NP1 positive. We have also observed the synaptic occurrence of C4 suggesting that activation of the classical pathway cannot be ruled out in synaptic plasticity in healthy adult animals. In summary, our results indicate that NPs play a regulatory role in the synaptic function of C1q. Whether this role can be intensified upon pathological conditions, such as in Alzheimer’s disease, is to be disclosed.
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Affiliation(s)
- Réka Á Kovács
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Henrietta Vadászi
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Éva Bulyáki
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - György Török
- Molecular Cell Biology Research Group, Institute of Enzymology, Research Center for Natural Sciences, Hungarian Academy of Sciences Centre of Excellence, Budapest, Hungary.,Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - Vilmos Tóth
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary.,Laboratory of Proteomics, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Dominik Mátyás
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary.,Laboratory of Proteomics, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Judit Kun
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Éva Hunyadi-Gulyás
- Laboratory of Proteomics Research, Biological Research Centre, Eötvös Loránd Research Network (ELKH), Szeged, Hungary
| | - Flóra Zsófia Fedor
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary.,Doctoral School of Chemical Engineering and Material Sciences, Pannon University, Veszprém, Hungary
| | - Ádám Csincsi
- Complement Research Group, Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Katalin Medzihradszky
- Laboratory of Proteomics Research, Biological Research Centre, Eötvös Loránd Research Network (ELKH), Szeged, Hungary
| | - László Homolya
- Molecular Cell Biology Research Group, Institute of Enzymology, Research Center for Natural Sciences, Hungarian Academy of Sciences Centre of Excellence, Budapest, Hungary
| | - Gábor Juhász
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary.,Laboratory of Proteomics, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Katalin A Kékesi
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary.,Laboratory of Proteomics, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary.,Department of Physiology and Neurobiology, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Mihály Józsi
- Complement Research Group, Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Balázs A Györffy
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary.,Laboratory of Proteomics, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - József Kardos
- ELTE NAP Neuroimmunology Research Group, Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
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Xiong X, Li C, Zheng Z, Du X. Novel globular C1q domain-containing protein (PmC1qDC-1) participates in shell formation and responses to pathogen-associated molecular patterns stimulation in Pinctada fucata martensii. Sci Rep 2021; 11:1105. [PMID: 33441832 PMCID: PMC7806589 DOI: 10.1038/s41598-020-80295-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 12/18/2020] [Indexed: 12/13/2022] Open
Abstract
The C1q protein, which contains the globular C1q (gC1q) domain, is involved in the innate immune response, and is found abundantly in the shell, and it participates in the shell formation. In this study, a novel gC1q domain-containing gene was identified from Pinctada fucata martensii (P. f. martensii) and designated as PmC1qDC-1. The full-length sequence of PmC1qDC-1 was 902 bp with a 534 bp open reading frame (ORF), encoding a polypeptide of 177 amino acids. Quantitative real-time PCR (qRT-PCR) result showed that PmC1qDC-1 was widely expressed in all tested tissues, including shell formation-associated tissue and immune-related tissue. PmC1qDC-1 expression was significantly high in the blastula and gastrula and especially among the juvenile stage, which is the most important stage of dissoconch shell formation. PmC1qDC-1 expression was located in the outer epithelial cells of mantle pallial and mantle edge and irregular crystal tablets were observed in the nacre upon knockdown of PmC1qDC-1 expression at mantle pallial. Moreover, the recombined protein PmC1qDC-1 increased the rate of calcium carbonate precipitation. Besides, PmC1qDC-1 expression was significantly up-regulated in the mantle pallial at 6 h and was significantly up-regulated in the mantle edge at 12 h and 24 h after shell notching. The expression level of PmC1qDC-1 in mantle edge was significantly up-regulated at 48 h after LPS stimulation and was significantly up-regulated at 12 h, 24 h and 48 h after poly I:C stimulation. Moreover, PmC1qDC-1 expression was significantly up-regulated in hemocytes at 6 h after lipopolysaccharide (LPS) and poly I:C challenge. These findings suggest that PmC1qDC-1 plays a crucial role both in the shell formation and the innate immune response in pearl oysters, providing new clues for understanding the shell formation and defense mechanism in mollusk.
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Affiliation(s)
- Xinwei Xiong
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China
| | - Chuyi Li
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China
| | - Zhe Zheng
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China.
- Pearl Breeding and Processing Engineering Technology Research Centre of Guangdong Province, Zhanjiang, 524088, China.
- Guangdong Science and Innovation Center for Pearl Culture, Zhanjiang, 524088, China.
- Guangdong Provincial Engineering Laboratory for Mariculture Organism Breeding, Zhanjiang, 524088, China.
| | - Xiaodong Du
- Fishery College, Guangdong Ocean University, Zhanjiang, 524088, China.
- Pearl Breeding and Processing Engineering Technology Research Centre of Guangdong Province, Zhanjiang, 524088, China.
- Guangdong Science and Innovation Center for Pearl Culture, Zhanjiang, 524088, China.
- Guangdong Provincial Engineering Laboratory for Mariculture Organism Breeding, Zhanjiang, 524088, China.
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5
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Syed I, Wooten RM. Interactions Between Pathogenic Burkholderia and the Complement System: A Review of Potential Immune Evasion Mechanisms. Front Cell Infect Microbiol 2021. [PMID: 34660335 DOI: 10.1086/69216810.3389/fcimb.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023] Open
Abstract
The genus Burkholderia contains over 80 different Gram-negative species including both plant and human pathogens, the latter of which can be classified into one of two groups: the Burkholderia pseudomallei complex (Bpc) or the Burkholderia cepacia complex (Bcc). Bpc pathogens Burkholderia pseudomallei and Burkholderia mallei are highly virulent, and both have considerable potential for use as Tier 1 bioterrorism agents; thus there is great interest in the development of novel vaccines and therapeutics for the prevention and treatment of these infections. While Bcc pathogens Burkholderia cenocepacia, Burkholderia multivorans, and Burkholderia cepacia are not considered bioterror threats, the incredible impact these infections have on the cystic fibrosis community inspires a similar demand for vaccines and therapeutics for the prevention and treatment of these infections as well. Understanding how these pathogens interact with and evade the host immune system will help uncover novel therapeutic targets within these organisms. Given the important role of the complement system in the clearance of bacterial pathogens, this arm of the immune response must be efficiently evaded for successful infection to occur. In this review, we will introduce the Burkholderia species to be discussed, followed by a summary of the complement system and known mechanisms by which pathogens interact with this critical system to evade clearance within the host. We will conclude with a review of literature relating to the interactions between the herein discussed Burkholderia species and the host complement system, with the goal of highlighting areas in this field that warrant further investigation.
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Affiliation(s)
- Irum Syed
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH, United States
| | - R Mark Wooten
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH, United States
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6
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Yan F, Zhou E, Liu S, Gao A, Kong L, Li B, Tu X, Guo Z, Mo J, Chen M, Ye J. Complement C1q subunit molecules from Xenopus laevis possess conserved function in C1q-immunoglobulin interaction. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2020; 103:103532. [PMID: 31678076 DOI: 10.1016/j.dci.2019.103532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 10/25/2019] [Accepted: 10/25/2019] [Indexed: 06/10/2023]
Abstract
Complement component 1q (C1q), together with C1r and C1s to form C1, recognize and bind immune complex to initiate the classical complement pathway. In this study, C1q subunit molecules (XlC1qA, XlC1qB, XlC1qC) were cloned and analyzed from Xenopus laevis (X. laevis). The open reading frame (ORF) of XlC1qA is 819 bp of nucleotide sequence encoding 272 amino acids, the ORF of XlC1qB is 711 bp encoding 236 aa, and the XlC1qC is consists of 732 bp encoding 243 aa. The deduced amino acid sequences contain a collagen-like region (CLR), Gly-X-Y repeats in the N-terminus and a C1q family domain at the C-terminus. Phylogenetic analysis revealed that the XlC1qs are clustered with the amphibian clade. Expression analysis indicated that the XlC1qs exhibited constitutive expression in all examined tissues, with the highest expression in liver. Additionally, XlC1q could interact with heat-aggregated mouse IgG and IgM, Xenopus IgM and Nile tilapia IgM, respectively, indicating the functional conservation of XlC1q binding to immunoglobulins. Further, XlC1qs can inhibit C1q-dependent hemolysis of sensitized sheep red blood cells with concentration-dependent manner. These data collectively suggest that the function of C1qs in X. laevis may be conserved in interaction with immunoglobulins, as that of mammals and teleosts.
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Affiliation(s)
- Fangfang Yan
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China
| | - Enxu Zhou
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China
| | - Shuo Liu
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China
| | - Along Gao
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China
| | - Linghe Kong
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China
| | - Bingxi Li
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China
| | - Xiao Tu
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China
| | - Zheng Guo
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China
| | - Jinfeng Mo
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China
| | - Meng Chen
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China.
| | - Jianmin Ye
- Institute of Modern Aquaculture Science and Engineering, School of Life Sciences, South China Normal University, Guangdong Provincial Key Laboratory for Healthy and Safe Aquaculture, Guangdong, 510631, PR China.
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7
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Datta D, Leslie SN, Morozov YM, Duque A, Rakic P, van Dyck CH, Nairn AC, Arnsten AFT. Classical complement cascade initiating C1q protein within neurons in the aged rhesus macaque dorsolateral prefrontal cortex. J Neuroinflammation 2020; 17:8. [PMID: 31906973 PMCID: PMC6945481 DOI: 10.1186/s12974-019-1683-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 12/17/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Cognitive impairment in schizophrenia, aging, and Alzheimer's disease is associated with spine and synapse loss from the dorsolateral prefrontal cortex (dlPFC) layer III. Complement cascade signaling is critical in driving spine loss and disease pathogenesis. Complement signaling is initiated by C1q, which tags synapses for elimination. C1q is thought to be expressed predominately by microglia, but its expression in primate dlPFC has never been examined. The current study assayed C1q levels in aging primate dlPFC and rat medial PFC (mPFC) and used immunoelectron microscopy (immunoEM), immunoblotting, and co-immunoprecipitation (co-IP) to reveal the precise anatomical distribution and interactions of C1q. METHODS Age-related changes in C1q levels in rhesus macaque dlPFC and rat mPFC were examined using immunoblotting. High-spatial resolution immunoEM was used to interrogate the subcellular localization of C1q in aged macaque layer III dlPFC and aged rat layer III mPFC. co-IP techniques quantified protein-protein interactions for C1q and proteins associated with excitatory and inhibitory synapses in macaque dlPFC. RESULTS C1q levels were markedly increased in the aged macaque dlPFC. Ultrastructural localization found the expected C1q localization in glia, including those ensheathing synapses, but also revealed extensive localization within neurons. C1q was found near synapses, within terminals and in spines, but was also observed in dendrites, often near abnormal mitochondria. Similar analyses in aging rat mPFC corroborated the findings in rhesus macaques. C1q protein increasingly associated with PSD95 with age in macaque, consistent with its synaptic localization as evidenced by EM. CONCLUSIONS These findings reveal novel, intra-neuronal distribution patterns for C1q in the aging primate cortex, including evidence of C1q in dendrites. They suggest that age-related changes in the dlPFC may increase C1q expression and synaptic tagging for glial phagocytosis, a possible mechanism for age-related degeneration.
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Affiliation(s)
- Dibyadeep Datta
- Department of Neuroscience, Yale University School of Medicine, 333 Cedar St., New Haven, CT, 06511, USA.
| | - Shannon N Leslie
- Department of Psychiatry, Yale University School of Medicine, New Haven, USA
- Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, USA
| | - Yury M Morozov
- Department of Neuroscience, Yale University School of Medicine, 333 Cedar St., New Haven, CT, 06511, USA
| | - Alvaro Duque
- Department of Neuroscience, Yale University School of Medicine, 333 Cedar St., New Haven, CT, 06511, USA
| | - Pasko Rakic
- Department of Neuroscience, Yale University School of Medicine, 333 Cedar St., New Haven, CT, 06511, USA
| | - Christopher H van Dyck
- Department of Neuroscience, Yale University School of Medicine, 333 Cedar St., New Haven, CT, 06511, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, USA
| | - Angus C Nairn
- Department of Psychiatry, Yale University School of Medicine, New Haven, USA
| | - Amy F T Arnsten
- Department of Neuroscience, Yale University School of Medicine, 333 Cedar St., New Haven, CT, 06511, USA.
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8
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Du X, Wang GH, Yue B, Wang JJ, Gu QQ, Zhou S, Zhang M, Hu YH. A novel C1q domain containing protein in black rockfish (Sebastes schlegelii) serves as a pattern recognition receptor with immunoregulatory properties and possesses binding activity to heat-aggregated IgG. FISH & SHELLFISH IMMUNOLOGY 2019; 87:73-81. [PMID: 30615989 DOI: 10.1016/j.fsi.2019.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 12/28/2018] [Accepted: 01/03/2019] [Indexed: 06/09/2023]
Abstract
C1q-domain-containing (C1qDC) proteins, which are involved in a series of immune responses, are important pattern recognition receptors in innate immunity in vertebrates and invertebrates. Functional studies of C1qDC proteins in vertebrates are scarce. In the present study, a C1qDC protein (SsC1qDC) from the teleost black rockfish (Sebastes schlegelii) was identified and examined at expression and functional levels. The open reading frame of SsC1qDC is 636 bp, and the predicted amino acid sequence of SsC1qDC shares 62%-69% overall identity with the C1qDC proteins of several fish species. SsC1qDC possesses conserved C1qDC features, including a signal sequence and a C1q domain. SsC1qDC was expressed in different tissues and its expression was up-regulated by bacterial and viral infection. Recombinant SsC1qDC (rSsC1qDC) exhibited apparent binding activities against PAMPs including LPS and PGN. rSsC1qDC had antibacterial activity against Vibrio parahaemolyticus, and was able to enhance the phagocytic activity of macrophages towards Vibrio anguillarum. rSsC1qDC interacted with human heat-aggregated IgG. Furthermore, in the presence of rSsC1qDC, fish exhibited enhanced resistance against bacterial infection. Collectively, these results indicated that SsC1qDC serves as a pattern recognition receptor and plays a vital role in the defense system of black rockfish.
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Affiliation(s)
- Xue Du
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China; Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, China
| | - Guang-Hua Wang
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Bin Yue
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Jing-Jing Wang
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Qin-Qin Gu
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Shun Zhou
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China
| | - Min Zhang
- Marine Science and Engineering College, Qingdao Agricultural University, Qingdao, 266109, China.
| | - Yong-Hua Hu
- Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China; Hainan Provincial Key Laboratory for Functional Components Research and Utilization of Marine Bio-resources, Haikou, 571101, China.
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9
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Zong Y, Liu Z, Wu Z, Han Z, Wang L, Song L. A novel globular C1q domain containing protein (C1qDC-7) from Crassostrea gigas acts as pattern recognition receptor with broad recognition spectrum. FISH & SHELLFISH IMMUNOLOGY 2019; 84:920-926. [PMID: 30385248 DOI: 10.1016/j.fsi.2018.10.079] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 10/23/2018] [Accepted: 10/28/2018] [Indexed: 06/08/2023]
Abstract
The globular C1q domain containing (C1qDC) proteins are a family of versatile pattern recognition receptors (PRRs) to bind various ligands by their globular C1q (gC1q) domain. In the present study, a novel globular C1qDC (CgC1qDC-7) was characterized from Pacific oyster Crassostrea gigas. The open reading frame of CgC1qDC-7 was of 555 bp, encoding a polypeptide of 185 amino acids. Phylogenetic analysis indicated that CgC1qDC-7 shared high homology with C1qDCs from Crassostrea virginica, Mytilus galloprovincialis, and Mizuhopecten yessoensis. The mRNA transcripts of CgC1qDC-7 were widely expressed in all the tested tissues including mantle, gonad, gills, adductor muscle, hemocytes, hepatopancreas and labial palps, with the highest expression level in hemocytes and gills. The recombinant protein of CgC1qDC-7 (rCgC1qDC-7) exhibited binding activity towards Gram-negative bacteria (Vibrio splendidus, V. anguillarum, Escherichia coli, V. alginolyticus, and Aeromonas hydrophila), Gram-positive bacteria (Micrococcus luteus and Staphylococcus aureus) and fungi (Pichia pastoris and Yarrowia lipolytica), and displayed strongest binding affinity towards Gram-negative bacteria V. splendidus and V. anguillarum. It also exhibited affinity to vital pathogen-associated molecular patterns (PAMPs), such as lipopolysaccharide (LPS), peptidoglycan (PGN), mannan (MAN) and Poly (I:C) with high affinity towards LPS and PGN, and low affinity to MAN and Poly (I:C). These results collectively indicated that CgC1qDC-7 was a novel PRR in C. gigas with high binding affinity towards LPS and PGN as well as Gram-negative bacteria.
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Affiliation(s)
- Yanan Zong
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China
| | - Zhaoqun Liu
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China
| | - Zhaojun Wu
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China
| | - Zirong Han
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China
| | - Lingling Wang
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China
| | - Linsheng Song
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China.
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Yadav S, Prakash J, Saxena JK. Metal binding study of calreticulin: An immunomodulatory protein of human filarial parasite Brugia malayi. Int J Biol Macromol 2018; 117:1157-1168. [DOI: 10.1016/j.ijbiomac.2018.06.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/28/2018] [Accepted: 06/02/2018] [Indexed: 01/02/2023]
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11
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Saint-Cricq M, Carrete J, Gaboriaud C, Gravel E, Doris E, Thielens N, Mingo N, Ling WL. Human Immune Protein C1q Selectively Disaggregates Carbon Nanotubes. NANO LETTERS 2017; 17:3409-3415. [PMID: 28530824 DOI: 10.1021/acs.nanolett.7b00189] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We atomistically compute the change in free energy upon binding of the globular domain of the complement protein C1q to carbon nanotubes (CNTs) and graphene in solution. Our modeling results imply that C1q is able to disaggregate and disperse bundles of large diameter multiwalled CNTs but not those of thin single-walled CNTs, and we validate this prediction with experimental observations. The results support the view of a strong binding with potential implications for the understanding of the immune response and biomedical applications of graphitic nanomaterials.
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Affiliation(s)
- M Saint-Cricq
- Université Grenoble Alpes, CEA LITEN , F-38000 Grenoble, France
| | - J Carrete
- Université Grenoble Alpes, CEA LITEN , F-38000 Grenoble, France
| | - C Gaboriaud
- Université Grenoble Alpes, CEA, CNRS, IBS , F-38000 Grenoble, France
| | - E Gravel
- Service de Chimie Bioorganique et de Marquage (SCBM), CEA, Université Paris-Saclay , 91191 Gif-sur-Yvette, France
| | - E Doris
- Service de Chimie Bioorganique et de Marquage (SCBM), CEA, Université Paris-Saclay , 91191 Gif-sur-Yvette, France
| | - N Thielens
- Université Grenoble Alpes, CEA, CNRS, IBS , F-38000 Grenoble, France
| | - N Mingo
- Université Grenoble Alpes, CEA LITEN , F-38000 Grenoble, France
| | - W L Ling
- Université Grenoble Alpes, CEA, CNRS, IBS , F-38000 Grenoble, France
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12
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Zhao LL, Jin M, Li XC, Ren Q, Lan JF. Four C1q domain-containing proteins involved in the innate immune response in Hyriopsis cumingii. FISH & SHELLFISH IMMUNOLOGY 2016; 55:323-331. [PMID: 27288256 DOI: 10.1016/j.fsi.2016.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 06/01/2016] [Accepted: 06/04/2016] [Indexed: 06/06/2023]
Abstract
C1q is a key subcomponent of the complement C1 complex. This subcomponent contains a globular C1q (gC1q) domain with remarkable ligand binding properties. C1q domain-containing (C1qDC) proteins are composed of all proteins with a gC1q domain. C1qDC proteins exist in many invertebrates and recognize non-self-ligands. In our study, four C1qDC genes, namely, HcC1qDC1-HcC1qDC4, were identified from Hyriopsis cumingii. HcC1qDC1-HcC1qDC4 encode a protein of 224, 204, 305, and 332 amino acids, respectively. All C1qDC proteins consist of a gC1q domain at the C terminal. In addition to the gC1q domain, a coiled-coil region is found in HcC1qDC4. Multiple alignments and phylogenetic tree analysis revealed that the C1qDC proteins highly differ from one another. Tissue distribution analysis demonstrated that HcC1qDC1-HcC1qDC4 are widely distributed in hemocytes, hepatopancreas, gills, mantle, and foot. These C1qDC genes are regulated by bacteria to varying degrees. These recombinant HcC1qDC proteins exhibit a binding activity against different bacterial species. Our results may suggest the roles of HcC1qDC genes in anti-bacterial immune defense.
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Affiliation(s)
- Ling-Ling Zhao
- College of Fisheries, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China; Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, Nanjing, 210046, PR China
| | - Min Jin
- State Key Laboratory Breeding Base of Marine Genetic Resource, Third Institute of Oceanography, SOA, Xiamen, 361005, PR China
| | - Xin-Cang Li
- East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, PR China
| | - Qian Ren
- Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University, Nanjing, 210046, PR China; Key Laboratory of Animal Virology of Ministry of Agriculture and College of Life Sciences, Zhejiang University, Hangzhou, 310058, PR China.
| | - Jiang-Feng Lan
- College of Fisheries, Huazhong Agricultural University, Wuhan, Hubei, 430070, PR China.
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Wang L, Wang L, Zhang D, Jiang Q, Sun R, Wang H, Zhang H, Song L. A novel multi-domain C1qDC protein from Zhikong scallop Chlamys farreri provides new insights into the function of invertebrate C1qDC proteins. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2015; 52:202-214. [PMID: 26049063 DOI: 10.1016/j.dci.2015.05.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 05/20/2015] [Accepted: 05/20/2015] [Indexed: 06/04/2023]
Abstract
The C1q domain containing (C1qDC) proteins are a family of proteins possessing globular C1q (gC1q) domains, and they rely on this domain to recognize various ligands such as PAMPs, immunoglobulins, ligands on apoptotic cell. In the present study, a novel multi-domain C1qDC protein (CfC1qDC-2) was identified from scallop Chlamys farreri, and its full length cDNA was composed of 1648 bp, encoding a signal peptide and three typical gC1q domains. BLAST analysis revealed significant sequence similarity between CfC1qDC-2 and C1qDC proteins from mollusks. Three gC1q domains were predicted in its tertiary structure to form a tightly packed bell-shaped trimer, and each one adopted a typical 10-stranded sandwich fold with a jelly-roll topology and contained six aromatic amino acids forming the hydrophobic core. The mRNA transcripts of CfC1qDC-2 were mainly detected in the tissues of hepatopancreas and gonad of adult scallops, and the expression level was up-regulated in hemocytes after stimulated by LPS, PGN and β-glucan. During the embryonic development of scallop, the mRNA transcripts of CfC1qDC-2 were presented in all the detected stages, and the expression level was up-regulated from D-hinged larvae and reached the highest at eye-spot larvae. The recombinant protein of MBP-CfC1qDC-2 (rCfC1qDC-2) could bind various PAMPs including LPS, PGN, LTA, β-glucan, mannan as well as polyI:C, and different microorganisms including three Gram-negative bacteria, three Gram-positive bacteria and two yeasts, as well as scallop apoptotic cells. Meanwhile, rCfC1qDC-2 could interact with human heat-aggregated IgG and IgM, and inhibit the C1q-dependent hemolysis of rabbit serum. All these results indicated that CfC1qDC-2 could recognize not only PAMPs as a PRR, but also the apoptotic cells. Moreover, the similar structures and functions shared by CfC1qDC-2 and complement C1q provided a new insight into the evolution of C1qDC proteins in complement system.
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Affiliation(s)
- Leilei Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China; Lianyungang Maternal and child Health Hospital, Lianyungang 222001, China
| | - Lingling Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
| | - Daoxiang Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiufen Jiang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hao Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Huan Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
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Merle NS, Church SE, Fremeaux-Bacchi V, Roumenina LT. Complement System Part I - Molecular Mechanisms of Activation and Regulation. Front Immunol 2015; 6:262. [PMID: 26082779 PMCID: PMC4451739 DOI: 10.3389/fimmu.2015.00262] [Citation(s) in RCA: 979] [Impact Index Per Article: 108.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 05/11/2015] [Indexed: 12/12/2022] Open
Abstract
Complement is a complex innate immune surveillance system, playing a key role in defense against pathogens and in host homeostasis. The complement system is initiated by conformational changes in recognition molecular complexes upon sensing danger signals. The subsequent cascade of enzymatic reactions is tightly regulated to assure that complement is activated only at specific locations requiring defense against pathogens, thus avoiding host tissue damage. Here, we discuss the recent advances describing the molecular and structural basis of activation and regulation of the complement pathways and their implication on physiology and pathology. This article will review the mechanisms of activation of alternative, classical, and lectin pathways, the formation of C3 and C5 convertases, the action of anaphylatoxins, and the membrane-attack-complex. We will also discuss the importance of structure-function relationships using the example of atypical hemolytic uremic syndrome. Lastly, we will discuss the development and benefits of therapies using complement inhibitors.
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Affiliation(s)
- Nicolas S Merle
- UMR_S 1138, Cordeliers Research Center, Complement and Diseases Team, INSERM , Paris , France ; UMR_S 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMR_S 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, Université Pierre et Marie Curie-Paris , Paris , France
| | - Sarah Elizabeth Church
- UMR_S 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMR_S 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, Université Pierre et Marie Curie-Paris , Paris , France ; UMR_S 1138, Cordeliers Research Center, Integrative Cancer Immunology Team, INSERM , Paris , France
| | - Veronique Fremeaux-Bacchi
- UMR_S 1138, Cordeliers Research Center, Complement and Diseases Team, INSERM , Paris , France ; UMR_S 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMR_S 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, Université Pierre et Marie Curie-Paris , Paris , France ; Service d'Immunologie Biologique, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou , Paris , France
| | - Lubka T Roumenina
- UMR_S 1138, Cordeliers Research Center, Complement and Diseases Team, INSERM , Paris , France ; UMR_S 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMR_S 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, Université Pierre et Marie Curie-Paris , Paris , France
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15
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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: 643] [Impact Index Per Article: 71.4] [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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Ressl S, Vu BK, Vivona S, Martinelli DC, Südhof TC, Brunger AT. Structures of C1q-like proteins reveal unique features among the C1q/TNF superfamily. Structure 2015; 23:688-99. [PMID: 25752542 DOI: 10.1016/j.str.2015.01.019] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 01/27/2015] [Accepted: 01/28/2015] [Indexed: 11/16/2022]
Abstract
C1q-like (C1QL) -1, -2, and -3 proteins are encoded by homologous genes that are highly expressed in brain. C1QLs bind to brain-specific angiogenesis inhibitor 3 (BAI3), an adhesion-type G-protein coupled receptor that may regulate dendritic morphology by organizing actin filaments. To begin to understand the function of C1QLs, we determined high-resolution crystal structures of the globular C1q-domains of C1QL1, C1QL2, and C1QL3. Each structure is a trimer, with each protomer forming a jelly-roll fold consisting of 10 β strands. Moreover, C1QL trimers may assemble into higher-order oligomers similar to adiponectin and contain four Ca(2+)-binding sites along the trimeric symmetry axis, as well as additional surface Ca(2+)-binding sites. Mutation of Ca(2+)-coordinating residues along the trimeric symmetry axis lowered the Ca(2+)-binding affinity and protein stability. Our results reveal unique structural features of C1QLs among C1q/TNF superfamily proteins that may be associated with their specific brain functions.
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Affiliation(s)
- Susanne Ressl
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA.
| | - Brandon K Vu
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA
| | - Sandro Vivona
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA
| | - David C Martinelli
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA
| | - Thomas C Südhof
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford, CA 94305, USA
| | - Axel T Brunger
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford, CA 94305, USA; Departments of Neurology and Neurological Sciences, Photon Science, and Structural Biology, Stanford University, Stanford, CA 94305, USA.
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17
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Wang X, Harimoto K, Fuji R, Liu J, Li L, Wang P, Akaike T, Wang Z. Pinctada fucata mantle gene 4 (PFMG4) from pearl oyster mantle enhances osteoblast differentiation. Biosci Biotechnol Biochem 2014; 79:558-65. [PMID: 25485793 DOI: 10.1080/09168451.2014.987206] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The organic matrix of nacre has been reported for its effect on osteogenesis. It was found that PFMG4 (Pinctada fucata mantle gene 4) with an N-terminal signal peptide could be secreted into nacre of Pinctada fucata (P. fucata). Here, we report that PFMG4 is highly expressed in mantle tissue and has high homology with C1q protein in different species. In MC3T3-E1 osteoblast cells, we found that highly expressed PFMG4 could suppress cell proliferation and type I collagen expression, but it could increase alkaline phosphatase activity and mineralized deposition. These results show that PFMG4 has potential ability in enhancing osteoblast differentiation, suggesting a new idea in developing medicine for the therapy of osteoporosis.
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Affiliation(s)
- Xiaoyan Wang
- a Protein Science Key Laboratory of the Ministry of Education, School of Medicine , Tsinghua University , Beijing , P.R. China
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Miao H, Jia Y, Xie S, Wang X, Zhao J, Chu Y, Zhou Z, Shi Z, Song X, Li L. Structural insights into the C1q domain of Caprin-2 in canonical Wnt signaling. J Biol Chem 2014; 289:34104-13. [PMID: 25331957 DOI: 10.1074/jbc.m114.591636] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Previously, we have identified Caprin-2 as a new regulator in canonical Wnt signaling through a mechanism of facilitating LRP5/6 phosphorylation; moreover, we found that its C-terminal C1q-related domain (Cap2_CRD) is required for this process. Here, we determined the crystal structures of Cap2_CRD from human and zebrafish, which both associate as a homotrimer with calcium located at the symmetric center. Surprisingly, the calcium binding-deficient mutant exists as a more stable trimer than its wild-type counterpart. Further studies showed that this Caprin-2 mutant disabled in binding calcium maintains the activity of promoting LRP5/6 phosphorylation, whereas the mutations disrupting Cap2_CRD homotrimer did impair such activity. Together, our findings suggested that the C-terminal CRD domain of Caprin-2 forms a flexible homotrimer mediated by calcium and that such trimeric assembly is required for Caprin-2 to regulate canonical Wnt signaling.
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Affiliation(s)
- Haofei Miao
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yingying Jia
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Sichun Xie
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xin Wang
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jianfei Zhao
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Youjun Chu
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Zhilei Zhou
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Zhubing Shi
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xiaomin Song
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Lin Li
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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Yadav S, Gupta S, Selvaraj C, Doharey PK, Verma A, Singh SK, Saxena JK. In silico and in vitro studies on the protein-protein interactions between Brugia malayi immunomodulatory protein calreticulin and human C1q. PLoS One 2014; 9:e106413. [PMID: 25184227 PMCID: PMC4153637 DOI: 10.1371/journal.pone.0106413] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 07/31/2014] [Indexed: 12/20/2022] Open
Abstract
Filarial parasites modulate effective immune response of their host by releasing a variety of immunomodulatory molecules, which help in the long persistence of the parasite within the host. The present study was aimed to characterize an immunomodulatory protein of Brugia malayi and its interaction with the host immune component at the structural and functional level. Our findings showed that Brugia malayi Calreticulin (BmCRT) is responsible for the prevention of classical complement pathway activation via its interaction with the first component C1q of the human host. This was confirmed by inhibition of C1q dependent lysis of immunoglobulin-sensitized Red Blood Cells (S-RBCs). This is possibly the first report which predicts CRT-C1q interaction on the structural content of proteins to explain how BmCRT inhibits this pathway. The molecular docking of BmCRT-C1q complex indicated that C1qB chain (IgG/M and CRP binding sites on C1q) played a major role in the interaction with conserved and non-conserved regions of N and P domain of BmCRT. Out of 37 amino acids of BmCRT involved in the interaction, nine amino acids (Pro(126), Glu(132), His(147), Arg(151), His(153), Met(154), Lys(156), Ala(196) and Lys(212)) are absent in human CRT. Both ELISA and in silico analysis showed the significant role of Ca(+2) in BmCRT-HuC1q complex formation and deactivation of C1r2-C1s2. Molecular dynamics studies of BmCRT-HuC1q complex showed a deviation from ∼ 0.4 nm to ∼ 1.0 nm. CD analyses indicated that BmCRT is composed of 49.6% α helix, 9.6% β sheet and 43.6% random coil. These findings provided valuable information on the architecture and chemistry of BmCRT-C1q interaction and supported the hypothesis that BmCRT binds with huC1q at their targets (IgG/M, CRP) binding sites. This interaction enables the parasite to interfere with the initial stage of host complement activation, which might be helpful in parasites establishment. These results might be utilized for help in blocking the C1q/CRT interaction and preventing parasite infection.
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Affiliation(s)
- Sunita Yadav
- Division of Biochemistry, CSIR-Central Drug Research Institute, BS10/1, Sector 10, Jankipuram extension, Lucknow, Uttar Pradesh, India
| | - Smita Gupta
- Division of Biochemistry, CSIR-Central Drug Research Institute, BS10/1, Sector 10, Jankipuram extension, Lucknow, Uttar Pradesh, India
| | - Chandrabose Selvaraj
- Computer Aided Drug Design and Molecular Modeling Lab, Department of Bioinformatics, Alagappa University, Karaikudi, Tamilnadu, India
| | - Pawan Kumar Doharey
- Division of Biochemistry, CSIR-Central Drug Research Institute, BS10/1, Sector 10, Jankipuram extension, Lucknow, Uttar Pradesh, India
| | - Anita Verma
- Division of Biochemistry, CSIR-Central Drug Research Institute, BS10/1, Sector 10, Jankipuram extension, Lucknow, Uttar Pradesh, India
| | - Sanjeev Kumar Singh
- Computer Aided Drug Design and Molecular Modeling Lab, Department of Bioinformatics, Alagappa University, Karaikudi, Tamilnadu, India
| | - Jitendra Kumar Saxena
- Division of Biochemistry, CSIR-Central Drug Research Institute, BS10/1, Sector 10, Jankipuram extension, Lucknow, Uttar Pradesh, India
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Wang L, Wang L, Kong P, Yang J, Zhang H, Wang M, Zhou Z, Qiu L, Song L. A novel C1qDC protein acting as pattern recognition receptor in scallop Argopecten irradians. FISH & SHELLFISH IMMUNOLOGY 2012; 33:427-35. [PMID: 22691582 DOI: 10.1016/j.fsi.2012.05.032] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 05/03/2012] [Accepted: 05/29/2012] [Indexed: 05/26/2023]
Abstract
The C1q domain containing (C1qDC) proteins refer to a family of proteins containing the versatile charge pattern recognition globular C1q domain in the C-terminus, which could bind various ligands including PAMPs and trigger a serial of immune response. In this study, a novel C1qDC protein was identified from Argopecten irradians (designated as AiC1qDC-2). Its full-length cDNA was of 1062 bp with an open reading frame of 720 bp encoding a polypeptide of 240 amino acids containing a typical gC1q domain. This gC1q domain possessed the typical 10-stranded β-sandwich fold with a jelly-roll topology common to all C1q family members, and shared high homology with most of the other identified gC1q domains. The mRNA transcripts of AiC1qDC-2 were mainly detected in hepatopancreas, and also marginally detectable in mantle, gonad, adductor, gill and hemocytes. Its relative expression level in hemocytes was significantly up-regulated after challenges of fungi Pichia pastoris GS115 (P < 0.05), Gram-positive bacteria Micrococcus luteus (P < 0.05) and Gram-negative bacteria Vibrio anguillarum (P < 0.05). The recombinant protein of AiC1qDC-2 (rAiC1qDC-2) could bind various PAMPs, including LPS, PGN, polyI:C, mannan, β-1,3-glucan as well as Yeast-glucan, and displayed agglutinating activity to fungi P. pastoris GS115, Gram-positive bacteria Bacillus subtilis and Gram-negative bacteria Escherichia coli TOP10F' as well as V. anguillarum. All these results indicated that AiC1qDC-2 could function as a pattern recognition receptor to recognize various PAMPs on different pathogens in the innate immune responses of scallop, and provided new clues to understand the role of invertebrate C1qDC proteins in the ancient complement system.
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Affiliation(s)
- Leilei Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
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21
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Kantardjiev AA. Quantum.Ligand.Dock: protein-ligand docking with quantum entanglement refinement on a GPU system. Nucleic Acids Res 2012; 40:W415-22. [PMID: 22669908 PMCID: PMC3394274 DOI: 10.1093/nar/gks515] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Quantum.Ligand.Dock (protein-ligand docking with graphic processing unit (GPU) quantum entanglement refinement on a GPU system) is an original modern method for in silico prediction of protein-ligand interactions via high-performance docking code. The main flavour of our approach is a combination of fast search with a special account for overlooked physical interactions. On the one hand, we take care of self-consistency and proton equilibria mutual effects of docking partners. On the other hand, Quantum.Ligand.Dock is the the only docking server offering such a subtle supplement to protein docking algorithms as quantum entanglement contributions. The motivation for development and proposition of the method to the community hinges upon two arguments-the fundamental importance of quantum entanglement contribution in molecular interaction and the realistic possibility to implement it by the availability of supercomputing power. The implementation of sophisticated quantum methods is made possible by parallelization at several bottlenecks on a GPU supercomputer. The high-performance implementation will be of use for large-scale virtual screening projects, structural bioinformatics, systems biology and fundamental research in understanding protein-ligand recognition. The design of the interface is focused on feasibility and ease of use. Protein and ligand molecule structures are supposed to be submitted as atomic coordinate files in PDB format. A customization section is offered for addition of user-specified charges, extra ionogenic groups with intrinsic pK(a) values or fixed ions. Final predicted complexes are ranked according to obtained scores and provided in PDB format as well as interactive visualization in a molecular viewer. Quantum.Ligand.Dock server can be accessed at http://87.116.85.141/LigandDock.html.
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Affiliation(s)
- Alexander A Kantardjiev
- Biophysical Chemistry Group, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Sofia 1113, Bulgaria.
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22
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Gu C, Jenkins SA, Xue Q, Xu Y. Activation of the classical complement pathway by Bacillus anthracis is the primary mechanism for spore phagocytosis and involves the spore surface protein BclA. THE JOURNAL OF IMMUNOLOGY 2012; 188:4421-31. [PMID: 22442442 DOI: 10.4049/jimmunol.1102092] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Interactions between spores of Bacillus anthracis and macrophages are critical for the development of anthrax infections, as spores are thought to use macrophages as vehicles to disseminate in the host. In this study, we report a novel mechanism for phagocytosis of B. anthracis spores. Murine macrophage-like cell line RAW264.7, bone marrow-derived macrophages, and primary peritoneal macrophages from mice were used. The results indicated that activation of the classical complement pathway (CCP) was a primary mechanism for spore phagocytosis. Phagocytosis was significantly reduced in the absence of C1q or C3. C3 fragments were found deposited on the spore surface, and the deposition was dependent on C1q and Ca(2+). C1q recruitment to the spore surface was mediated by the spore surface protein BclA, as recombinant BclA bound directly and specifically to C1q and inhibited C1q binding to spores in a dose-dependent manner. C1q binding to spores lacking BclA (ΔbclA) was also significantly reduced compared with wild-type spores. In addition, deposition of both C3 and C4 as well as phagocytosis of spores were significantly reduced when BclA was absent, but were not reduced in the absence of IgG, suggesting that BclA, but not IgG, is important in these processes. Taken together, these results support a model in which spores actively engage CCP primarily through BclA interaction with C1q, leading to CCP activation and opsonophagocytosis of spores in an IgG-independent manner. These findings are likely to have significant implications on B. anthracis pathogenesis and microbial manipulation of complement.
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Affiliation(s)
- Chunfang Gu
- Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
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23
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Gaboriaud C, Frachet P, Thielens NM, Arlaud GJ. The human c1q globular domain: structure and recognition of non-immune self ligands. Front Immunol 2012; 2:92. [PMID: 22566881 PMCID: PMC3342031 DOI: 10.3389/fimmu.2011.00092] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Accepted: 12/21/2011] [Indexed: 11/13/2022] Open
Abstract
C1q, the ligand-binding unit of the C1 complex of complement, is a pattern recognition molecule with the unique ability to sense an amazing variety of targets, including a number of altered structures from self, such as apoptotic cells. The three-dimensional structure of its C-terminal globular domain, responsible for its recognition function, has been solved by X-ray crystallography, revealing a tightly packed heterotrimeric assembly with marked differences in the surface patterns of the subunits, and yielding insights into its versatile binding properties. In conjunction with other approaches, this same technique has been used recently to decipher the mechanisms that allow this domain to interact with various non-immune self ligands, including molecules known to provide eat-me signals on apoptotic cells, such as phosphatidylserine and DNA. These investigations provide evidence for a common binding area for these ligands located in subunit C of the C1q globular domain, and suggest that ligand recognition through this area down-regulates C1 activation, hence contributing to the control of the inflammatory reaction. The purpose of this article is to give an overview of these advances which represent a first step toward understanding the recognition mechanisms of C1q and their biological implications.
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Characterization of factors influencing on-chip complement activation to optimize parallel measurement of antibody and complement proteins on antigen microarrays. J Immunol Methods 2012; 375:75-83. [DOI: 10.1016/j.jim.2011.09.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 09/14/2011] [Accepted: 09/21/2011] [Indexed: 12/20/2022]
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25
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Radanova M, Vasilev V, Deliyska B, Kishore U, Ikonomov V, Ivanova D. Anti-C1q autoantibodies specific against the globular domain of the C1qB-chain from patient with lupus nephritis inhibit C1q binding to IgG and CRP. Immunobiology 2011; 217:684-91. [PMID: 22209113 DOI: 10.1016/j.imbio.2011.11.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Revised: 06/29/2011] [Accepted: 11/22/2011] [Indexed: 01/27/2023]
Abstract
Lupus nephritis is one of the most severe manifestations of systemic lupus erythematosus. Higher titers of serum anti-C1q autoantibodies correlate with disease activity in patients with lupus nephritis. Anti-C1q autoantibodies have been shown to bind neo-epitopes within the collagen region of human C1q. In a preliminary study, we recently reported that the anti-C1q autoantibodies could also recognize epitopes within the globular domain (gC1q) of the C1q molecule. Here, 38 sera from patients with renal biopsy-proven lupus nephritis were screened for the presence of anti-gC1q autoantibodies, using recombinant globular head regions of individual A (ghA), B (ghB) and C (ghC) chains of human C1q. We isolated anti-gC1q autoantibodies from three selected patients. Human C1q was pre-incubated with increasing concentrations of the isolated anti-ghA, anti-ghB or anti-ghC autoantibodies and its binding to different C1q target molecules such as IgG and CRP was then evaluated. Anti-ghB, but not anti-ghA and anti-ghC autoantibodies, markedly inhibited C1q interaction with IgG as well as CRP. These results appear to suggest that the anti-ghB autoantibodies may partially induce acquired functional C1q deficiency and thus may interfere with the biological function of C1q.
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Affiliation(s)
- Maria Radanova
- Department of Biochemistry, Molecular Medicine and Nutrigenomics, Medical University - Varna, Varna, Bulgaria.
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26
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Kantardjiev AA. GPU.proton.DOCK: Genuine Protein Ultrafast proton equilibria consistent DOCKing. Nucleic Acids Res 2011; 39:W223-8. [PMID: 21666258 PMCID: PMC3125792 DOI: 10.1093/nar/gkr412] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
GPU.proton.DOCK (Genuine Protein Ultrafast proton equilibria consistent DOCKing) is a state of the art service for in silico prediction of protein–protein interactions via rigorous and ultrafast docking code. It is unique in providing stringent account of electrostatic interactions self-consistency and proton equilibria mutual effects of docking partners. GPU.proton.DOCK is the first server offering such a crucial supplement to protein docking algorithms—a step toward more reliable and high accuracy docking results. The code (especially the Fast Fourier Transform bottleneck and electrostatic fields computation) is parallelized to run on a GPU supercomputer. The high performance will be of use for large-scale structural bioinformatics and systems biology projects, thus bridging physics of the interactions with analysis of molecular networks. We propose workflows for exploring in silico charge mutagenesis effects. Special emphasis is given to the interface-intuitive and user-friendly. The input is comprised of the atomic coordinate files in PDB format. The advanced user is provided with a special input section for addition of non-polypeptide charges, extra ionogenic groups with intrinsic pKa values or fixed ions. The output is comprised of docked complexes in PDB format as well as interactive visualization in a molecular viewer. GPU.proton.DOCK server can be accessed at http://gpudock.orgchm.bas.bg/.
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Affiliation(s)
- Alexander A Kantardjiev
- Biophysical Chemistry Group, Institute of Organic Chemistry, Bulgarian Academy of Sciences, and Department of Physics, Sofia University, Sofia, Bulgaria.
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27
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Roumenina LT, Radanova M, Atanasov BP, Popov KT, Kaveri SV, Lacroix-Desmazes S, Frémeaux-Bacchi V, Dimitrov JD. Heme interacts with c1q and inhibits the classical complement pathway. J Biol Chem 2011; 286:16459-69. [PMID: 21454703 DOI: 10.1074/jbc.m110.206136] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
C1q is the recognition subunit of the first component of the classical complement pathway. It participates in clearance of immune complexes and apoptotic cells as well as in defense against pathogens. Inappropriate activation of the complement contributes to cellular and tissue damage in different pathologies, urging the need for the development of therapeutic agents that are able to inhibit the complement system. In this study, we report heme as an inhibitor of C1q. Exposure of C1q to heme significantly reduced the activation of the classical complement pathway, mediated by C-reactive protein (CRP) and IgG. Interaction analyses revealed that heme reduces the binding of C1q to CRP and IgG. Furthermore, we demonstrated that the inhibition of C1q interactions results from a direct binding of heme to C1q. Formation of complex of heme with C1q caused changes in the mechanism of recognition of IgG and CRP. Taken together, our data suggest that heme is a natural negative regulator of the classical complement pathway at the level of C1q. Heme may play a role at sites of excessive tissue damage and hemolysis where large amounts of free heme are released.
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Affiliation(s)
- Lubka T Roumenina
- Centre de Recherche des Cordeliers, Université Pierre et Marie Curie, Paris 6, UMR S 872, Paris, France.
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28
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Dimitrov JD, Roumenina LT, Plantier JL, Andre S, Saboulard D, Meslier Y, Planchais C, Jacquemin M, Saint-Remy JM, Atanasov BP, Kaveri SV, Lacroix-Desmazes S. A human FVIII inhibitor modulates FVIII surface electrostatics at a VWF-binding site distant from its epitope. J Thromb Haemost 2010; 8:1524-31. [PMID: 20374449 DOI: 10.1111/j.1538-7836.2010.03878.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
SUMMARY BACKGROUND BO2C11 is a human monoclonal factor (F) VIII inhibitor. When bound to the C2 domain of FVIII, the Fab fragment of BO2C11 (Fab(BO2C11)) buries a surface of C2 that contains residues participating in a binding site for von Willebrand factor (VWF). BO2C11 has thus been proposed to neutralize FVIII by steric hindrance. OBJECTIVES The BO2C11 epitope on C2 overlaps with residues located at the periphery of the putative VWF binding site; hence, most of the residues that constitute the VWF binding site on C2 and a3 remain accessible for VWF interaction following BO2C11/FVIII complex formation. We thus investigated the contribution of alternative molecular mechanisms to FVIII inactivation by BO2C11. METHODS Continuum electrostatic calculations were applied to the crystal structure of C2, free or Fab(BO2C11)-complexed. In silico predictions were confirmed by site-directed mutagenesis and VWF-binding assays of the mutated FVIII. RESULTS Binding of Fab(BO2C11) to C2 induced perturbations in the electrostatic potential of C2 and in the local electrostatic parameters of 18 charged residues in C2, which are distant from the BO2C11 epitope. Nine of the predicted electrostatic hotspots clustered on the VWF-binding site of C2. Mutation of some of the predicted electrostatic hotspots has been associated with hemophilia A and reduced VWF binding in vitro. CONCLUSIONS Inhibitors may neutralize FVIII by alteration of protein surface electrostatics at a long distance from their epitope. Perturbation of the electrostatic environment of C2, either upon binding by anti-FVIII antibodies or consecutive to missense mutations in the F8 gene, may lead to hampered VWF binding and reduced FVIII residence time in circulation.
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Affiliation(s)
- J D Dimitrov
- Centre de Recherche des Cordeliers, Université Pierre et Marie Curie - Paris6, UMR S 872, Paris, France
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29
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Kantardjiev AA, Atanasov BP. PHEMTO: protein pH-dependent electric moment tools. Nucleic Acids Res 2009; 37:W422-7. [PMID: 19420068 PMCID: PMC2703894 DOI: 10.1093/nar/gkp336] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2009] [Revised: 04/17/2009] [Accepted: 04/21/2009] [Indexed: 11/13/2022] Open
Abstract
PHEMTO (protein pH-dependent electric moment tools) is released in response to the high demand in protein science community for evaluation of electrostatic characteristics in relations to molecular recognition. PHEMTO will serve protein scientists with new advanced features for analysis of protein molecular interactions: Electric/dipole moments, their pH-dependence and in silico charge mutagenesis effects on these properties as well as alternative algorithms for electric/dipole moment computation--Singular value decomposition of electrostatic potential (EP) to account for reaction field. The implementation is based on long-term experience--PHEI mean field electrostatics and PHEPS server for evaluation of global and local pH-dependent properties. However, PHEMTO is not just an update of our PHEPS server. Besides standard electrostatics, we offer new, advanced and useful features for analysis of protein molecular interactions. In addition our algorithms are very fast. Special emphasis is given to the interface--intuitive and user-friendly. The input is comprised of the atomic coordinate file in Protein Data Bank format. The advanced user is provided with a special input section for addition of non-polypeptide charges. The output covers actually full electrostatic characteristics but special emphasis is given to electric/dipole moments and their interactive visualization. PHEMTO server can be accessed at http://phemto.orgchm.bas.bg/.
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Affiliation(s)
| | - Boris P. Atanasov
- Biophysical Chemistry Group, Institute of Organic Chemistry, Bulgarian Academy of Sciences, Sofia-1113, Bulgaria
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30
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Gadjeva MG, Rouseva MM, Zlatarova AS, Reid KBM, Kishore U, Kojouharova MS. Interaction of human C1q with IgG and IgM: revisited. Biochemistry 2009; 47:13093-102. [PMID: 19006321 DOI: 10.1021/bi801131h] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The first step of activation of the classical complement pathway involves the binding of the globular C1q domain (gC1q) to the antigen-bound IgG or IgM. To improve our understanding of the mechanism of interaction of gC1q with IgG and IgM, we compared the immunoglobulin binding properties of single-residue mutants of individual globular modules of A and C chains. We found that Lys(A200) and Lys(C170) are significant for binding with both immunoglobulins. In addition, two C1q-specific scFv antibodies known as potent inhibitors of C1q-IgG and -IgM interactions were used in the epitope mapping analysis. A set of important residues, which participate in the C1q epitopes for scFv, were identified: Lys(C170) for the scFv3(V) epitope and Arg(B108) and Arg(B109) for the scFv10(V) epitope. The ability of scFv3(V) and scFv10(V) to bind preformed C1q-IgG or C1q-IgM complexes differed: scFv3(V) retained its ability to bind C1q, while scFv10(V) lost it. Given the different locations of the epitopes and the varying abilities of both antibodies to bind C1q-IgG and C1q-IgM complexes, we found that residues from the apical surface of C1q [where the scFv3(V) epitope was located] were involved in the initial recognition of IgG and IgM, while Arg(B108) and Arg(B109) are able to interact during the initial recognition as well as during the final binding of immunoglobulins. The reported results provide the first experimental evidence supporting the notion that apical and equatorial surfaces of gC1q have consecutive involvement following the gC1q reorientation during the interaction with specific C1q ligands.
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Affiliation(s)
- Mihaela G Gadjeva
- Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
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31
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Kang YH, Tan LA, Carroll MV, Gentle ME, Sim RB. Target pattern recognition by complement proteins of the classical and alternative pathways. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 653:117-28. [PMID: 19799115 DOI: 10.1007/978-1-4419-0901-5_8] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
The complement system is a major component of the innate defence of animals against invading microorganisms, and is also essential for the recognition and clearance of damaged or structurally-altered host cells or macromolecules. The system is activated by three different pathways, each of which responds, using different recognition molecules, to a very wide range of activators. The recognition protein of the complement classical pathway, C1q is described in detail here, with comparisons to the alternative pathway.
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Affiliation(s)
- Yu-Hoi Kang
- MRC Immunochemistry Unit, Department of Biochemistry, University of Oxford, Oxford, UK
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32
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Yu Y, Huang H, Wang Y, Yu Y, Yuan S, Huang S, Pan M, Feng K, Xu A. A Novel C1q Family Member of Amphioxus Was Revealed to Have a Partial Function of Vertebrate C1q Molecule. THE JOURNAL OF IMMUNOLOGY 2008; 181:7024-32. [DOI: 10.4049/jimmunol.181.10.7024] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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33
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Roumenina L, Bureeva S, Kantardjiev A, Karlinsky D, Andia-Pravdivy JE, Sim R, Kaplun A, Popov M, Kishore U, Atanasov B. Complement C1q-target proteins recognition is inhibited by electric moment effectors. J Mol Recognit 2008; 20:405-15. [PMID: 17929239 DOI: 10.1002/jmr.853] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Classical complement pathway is an important innate immune mechanism, which is usually triggered by binding of C1q to immunoglobulins, pentraxins and other target molecules. Although the activation of the classical pathway is crucial in the host defence, its undesirable and uncontrolled activation can lead to tissue damage. Thus, understanding the molecular basis of complement activation and its inhibition are of great biomedical importance. Recently, we proposed a mechanism for target recognition and classical pathway activation by C1q, which is likely governed by calcium-controlled reorientation of macromolecular electric moment vectors. Here we sought to define the mechanism of C1q inhibition by low molecular weight disulphate compounds that bind to the globular (gC1q) domain, using experimental, computational docking and theoretical modelling approaches. Our experimental results demonstrate that betulin disulphate (B2S) and 9,9-bis(4'-hydroxyphenyl)fluorene disulphate (F2S) inhibit the interaction of C1q and its recombinant globular modules with target molecules IgG1, C-reactive protein (CRP) and long pentraxin 3 (PTX3). In most C1q-inhibitor docked complexes, there is a reduction of electric moment scalar values and similarly altered direction of electric/dipole moment vectors. This could explain the inhibitory effect by impaired electrostatic steering, lacking optimal target recognition and formation of functional complex. In the presence of the inhibitor, the tilt of gC1q domains is likely to be blocked by the altered direction of the electric moment vector. Thus, the transition from the inactive (closed) towards the active (open) conformation of C1q (i.e. the complement activation signal transmission) will be impaired and the cascade initiation disrupted. These results could serve as a starting point for the exploration of a new form of 'electric moment inhibitors/effectors'.
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Affiliation(s)
- Lubka Roumenina
- Department of Biochemistry, Sofia University, St. Kliment Ohridski, 8 Dragan Tsankov St., Sofia 1164, Bulgaria
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34
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Roumenina LT, Popov KT, Bureeva SV, Kojouharova M, Gadjeva M, Rabheru S, Thakrar R, Kaplun A, Kishore U. Interaction of the globular domain of human C1q with Salmonella typhimurium lipopolysaccharide. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1784:1271-6. [PMID: 18513495 DOI: 10.1016/j.bbapap.2008.04.029] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Revised: 04/25/2008] [Accepted: 04/29/2008] [Indexed: 12/29/2022]
Abstract
Gram-negative bacteria can bind complement protein C1q in an antibody-independent manner and activate classical pathway via their lipopolysaccharides (LPS). Earlier studies have implicated the collagen-like region of human C1q in binding LPS. In recent years, a number of C1q target molecules, previously considered to interact with collagen-like region of C1q, have been shown to bind via the globular domain (gC1q). Here we report, using recombinant forms of the globular head regions of C1q A, B and C chains, that LPS derived from Salmonella typhimurium interact specifically with the B-chain of the gC1q domain in a calcium-dependent manner. LPS and IgG-binding sites on the gC1q domain appear to be overlapping and this interaction can be inhibited by a synthetic C1q inhibitor, suggesting common interacting mechanisms.
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Affiliation(s)
- Lubka T Roumenina
- Department of Biochemistry, Sofia University, St. Kliment Ohridski, 8 Dragan Tsankov St., Sofia 1164, Bulgaria
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Baker VS, Imade GE, Molta NB, Tawde P, Pam SD, Obadofin MO, Sagay SA, Egah DZ, Iya D, Afolabi BB, Baker M, Ford K, Ford R, Roux KH, Keller TC. Cytokine-associated neutrophil extracellular traps and antinuclear antibodies in Plasmodium falciparum infected children under six years of age. Malar J 2008; 7:41. [PMID: 18312656 PMCID: PMC2275287 DOI: 10.1186/1475-2875-7-41] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Accepted: 02/29/2008] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND In Plasmodium falciparum-infected children, the relationships between blood cell histopathology, blood plasma components, development of immunocompetence and disease severity remain poorly understood. Blood from Nigerian children with uncomplicated malaria was analysed to gain insight into these relationships. This investigation presents evidence for circulating neutrophil extracellular traps (NETs) and antinuclear IgG antibodies (ANA). The presence of NETs and ANA to double-stranded DNA along with the cytokine profiles found suggests autoimmune mechanisms that could produce pathogenesis in children, but immunoprotection in adults. METHODS Peripheral blood smear slides and blood samples obtained from 21 Nigerian children under six years of age, presenting with uncomplicated malaria before and seven days after initiation of sulphadoxine-pyrimethamine (SP) treatment were analysed. The slides were stained with Giemsa and with DAPI. Levels of the pro-inflammatory cytokines IFN-gamma, IL-2, TNF, CRP, and IL-6, select anti-inflammatory cytokines TGF-beta and IL-10, and ANA were determined by immunoassay. RESULTS The children exhibited circulating NETs with adherent parasites and erythrocytes, elevated ANA levels, a Th2 dominated cytokine profile, and left-shifted leukocyte differential counts. Nonspecific ANA levels were significant in 86% of the children pretreatment and in 100% of the children seven days after SP treatment, but in only 33% of age-matched control samples collected during the season of low parasite transmission. Levels of ANA specific for dsDNA were significant in 81% of the children both pre-treatment and post treatment. CONCLUSION The results of this investigation suggest that NET formation and ANA to dsDNA may induce pathology in falciparum-infected children, but activate a protective mechanism against falciparum malaria in adults. The significance of in vivo circulating chromatin in NETs and dsDNA ANA as a causative factor in the hyporesponsiveness of CpG oligonucleotide-based malaria vaccines is discussed.
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Affiliation(s)
- Virginia S Baker
- Department of Biological Science, Florida State University, Tallahassee, Florida, USA.
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Peake PW, Shen Y, Walther A, Charlesworth JA. Adiponectin binds C1q and activates the classical pathway of complement. Biochem Biophys Res Commun 2008; 367:560-5. [PMID: 18179772 DOI: 10.1016/j.bbrc.2007.12.161] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Accepted: 12/21/2007] [Indexed: 02/06/2023]
Abstract
The adipose-specific protein adiponectin binds to a number of target molecules, including damaged endothelium and the surface of apoptotic cells. However, the significance of this binding remains unclear. This study demonstrates the binding of purified C1q to recombinant adiponectin under physiological conditions, and the dependence of this upon Ca(++) and Mg(++). Binding was enhanced by metaperiodate-mediated destruction of glucosylgalactosyl sugars on adiponectin. Adiponectin was bound by the globular domain of the A chain of collagenase-digested C1q, and C1q binding induced deposition of C4 and C3 through activation of the classical complement pathway. After Western blotting, affinity-purified adiponectin from human serum bound C1q, whereas adiponectin in whole serum did not, unless pre-treated with metaperiodate. These results suggest adiponectin is member of the pattern-recognition family of defence collagens, able to bind target molecules and activate complement. It may therefore play an important role in innate immunity and autoimmune phenomena.
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Affiliation(s)
- Philip W Peake
- Division of Medicine, Prince of Wales Hospital, High Street, Randwick, Sydney, NSW 2031, Australia
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Ghai R, Waters P, Roumenina LT, Gadjeva M, Kojouharova MS, Reid KBM, Sim RB, Kishore U. C1q and its growing family. Immunobiology 2007; 212:253-66. [PMID: 17544811 DOI: 10.1016/j.imbio.2006.11.001] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Accepted: 11/01/2006] [Indexed: 11/18/2022]
Abstract
C1q is the target recognition protein of the classical complement pathway and a major connecting link between innate and acquired immunity. As a charge pattern recognition molecule of innate immunity, C1q can engage a broad range of self and non-self ligands via its heterotrimeric globular (gC1q) domain and thus trigger the classical pathway. The trimeric gC1q signature domain has been identified in a variety of non-complement proteins that can be grouped together as a C1q family. The X-ray crystal structures of the gC1q domain of a few members of the C1q family reveal a compact jelly-roll beta-sandwich fold similar to that of the multifunctional tumor necrosis factor (TNF) ligand family, hence the C1q and TNF superfamily. This review is an update on the structural and functional aspects of the gC1q domain of human C1q. We also mention the diverse range of proteins that utilize a gC1q domain in order to reflect on its importance as a versatile scaffold to support a variety of functions.
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Affiliation(s)
- Rohit Ghai
- Institute of Medical Microbiology, Justus-Liebig-University, Frankfurter Strasse 107, 35392 Giessen, Germany
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38
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Dimitrov JD, Roumenina LT, Doltchinkova VR, Vassilev TL. Iron Ions and Haeme Modulate the Binding Properties of Complement Subcomponent C1q and of Immunoglobulins. Scand J Immunol 2007; 65:230-9. [PMID: 17309777 DOI: 10.1111/j.1365-3083.2006.01893.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The complement system and circulating antibodies play a major role in the defence against infection. They act at the sites of inflammation, where the harsh microenvironment and the oxidative stress lead to the release of free iron ions and haeme. The aim of this study was to analyse the consequences of the exposure of C1q and immunoglobulins to iron ions or haeme. The changes in target recognition by C1q and in the rheumatoid factor activity of the immunoglobulins were investigated. The exposure of C1q to ferrous ions increased its binding to IgG and to IgM. In contrast, haeme inhibited C1q binding to all studied targets, especially to IgG1 and C-reactive protein. Thus, the haeme released as a result of tissue damage and oxidative stress may act as a negative feedback regulator of an inappropriate complement triggering as seen in ischaemia-reperfusion tissue injury. The results also show that iron ions and haeme were able to reveal rheumatoid factor activity of IgG. The modulation of the C1q-target binding as well as the revealing of rheumatoid factor activity of IgG by exposure to redox-active agents released at the sites of inflammation may have important consequences for the understanding of the immunopathological mechanisms of inflammatory and autoimmune diseases.
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Affiliation(s)
- J D Dimitrov
- Department of Immunology, Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, Sofia, Bulgaria.
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Degn SE, Thiel S, Jensenius JC. New perspectives on mannan-binding lectin-mediated complement activation. Immunobiology 2007; 212:301-11. [PMID: 17544815 DOI: 10.1016/j.imbio.2006.12.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2006] [Revised: 11/24/2006] [Accepted: 12/05/2006] [Indexed: 01/02/2023]
Abstract
The complement system is an important part of the innate immune system, mediating several major effector functions and modulating adaptive immune responses. Three complement activation pathways exist: the classical pathway (CP), the alternative pathway (AP), and the lectin pathway (LP). The LP is the most recently discovered, and least characterized. The CP and the LP are generally viewed as working through the generation of the C3 convertase, C4bC2b, and are here referred to as the "standard" pathways. In addition to the standard CP and LP, so-called bypass pathways have also been reported, allowing C3 activation in the absence of components otherwise believed critical. The classical bypass pathways are dependent on C1 and components of the AP. A recent study has shown the existence also of a lectin bypass pathway dependent on mannan-binding lectin (MBL) and AP components. The emerging picture of the complement system is more that of a small "scale-free" network where C3 acts as the main hub, than that of three linear pathways converging in a common terminal pathway.
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Affiliation(s)
- Søren E Degn
- Department of Medical Microbiology and Immunology, University of Aarhus, Denmark.
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Abstract
PHEPS (pH-dependent Protein Electrostatics Server) is a web service for fast prediction and experiment planning support, as well as for correlation and analysis of experimentally obtained results, reflecting charge-dependent phenomena in globular proteins. Its implementation is based on long-term experience (PHEI package) and the need to explain measured physicochemical characteristics at the level of protein atomic structure. The approach is semi-empirical and based on a mean field scheme for description and evaluation of global and local pH-dependent electrostatic properties: protein proton binding; ionic sites proton population; free energy electrostatic term; ionic groups proton affinities (pKa,i) and their Coulomb interaction with whole charge multipole; electrostatic potential of whole molecule at fixed pH and pH-dependent local electrostatic potentials at user-defined set of points. The speed of calculation is based on fast determination of distance-dependent pair charge-charge interactions as empirical three exponential function that covers charge–charge, charge–dipole and dipole–dipole contributions. After atomic coordinates input, all standard parameters are used as defaults to facilitate non-experienced users. Special attention was given to interactive addition of non-polypeptide charges, extra ionizable groups with intrinsic pKas or fixed ions. The output information is given as plain-text, readable by ‘RasMol’, ‘Origin’ and the like. The PHEPS server is accessible at .
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Affiliation(s)
| | - Boris P. Atanasov
- To whom correspondence should be addressed. Tel: +359-2 960 6123; Fax: +359-2 870 0225;
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Roumenina LT, Ruseva MM, Zlatarova A, Ghai R, Kolev M, Olova N, Gadjeva M, Agrawal A, Bottazzi B, Mantovani A, Reid KBM, Kishore U, Kojouharova MS. Interaction of C1q with IgG1, C-reactive protein and pentraxin 3: mutational studies using recombinant globular head modules of human C1q A, B, and C chains. Biochemistry 2006; 45:4093-104. [PMID: 16566583 PMCID: PMC3874390 DOI: 10.1021/bi052646f] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
C1q is the first subcomponent of the classical complement pathway that can interact with a range of biochemically and structurally diverse self and nonself ligands. The globular domain of C1q (gC1q), which is the ligand-recognition domain, is a heterotrimeric structure composed of the C-terminal regions of A (ghA), B (ghB), and C (ghC) chains. The expression and functional characterization of ghA, ghB, and ghC modules have revealed that each chain has specific and differential binding properties toward C1q ligands. It is largely considered that C1q-ligand interactions are ionic in nature; however, the complementary ligand-binding sites on C1q and the mechanisms of interactions are still unclear. To identify the residues on the gC1q domain that are likely to be involved in ligand recognition, we have generated a number of substitution mutants of ghA, ghB, and ghC modules and examined their interactions with three selected ligands: IgG1, C-reactive protein (CRP), and pentraxin 3 (PTX3). Our results suggest that charged residues belonging to the apex of the gC1q heterotrimer (with participation of all three chains) as well as the side of the ghB are crucial for C1q binding to these ligands, and their contribution to each interaction is different. It is likely that a set of charged residues from the gC1q surface participate via different ionic and hydrogen bonds with corresponding residues from the ligand, instead of forming separate binding sites. Thus, a recently proposed model suggesting the rotation of the gC1q domain upon ligand recognition may be extended to C1q interaction with CRP and PTX3 in addition to IgG1.
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Affiliation(s)
- Lubka T. Roumenina
- Department of Biochemistry, Sofia University, St. Kliment Ohridski, 8 Dragan Tsankov Street, Sofia 1164, Bulgaria
| | - Marieta M. Ruseva
- Department of Biochemistry, Sofia University, St. Kliment Ohridski, 8 Dragan Tsankov Street, Sofia 1164, Bulgaria
| | - Alexandra Zlatarova
- Department of Biochemistry, Sofia University, St. Kliment Ohridski, 8 Dragan Tsankov Street, Sofia 1164, Bulgaria
| | - Rohit Ghai
- Institute of Medical Microbiology, Faculty of Medicine, Justus-Liebig-University, Frankfurter Strasse 107, 35392 Giessen, Germany
| | - Martin Kolev
- Department of Biochemistry, Sofia University, St. Kliment Ohridski, 8 Dragan Tsankov Street, Sofia 1164, Bulgaria
| | - Neli Olova
- Department of Biochemistry, Sofia University, St. Kliment Ohridski, 8 Dragan Tsankov Street, Sofia 1164, Bulgaria
| | - Mihaela Gadjeva
- Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts 02115
| | - Alok Agrawal
- Department of Pharmacology, East Tennessee State University, Johnson City, Tennessee 37614
| | - Barbara Bottazzi
- Istituto Clinico Humanitas, Rozzano Milan, and Institute of General Pathology, Faculty of Medicine, University of Milan, Italy
| | - Alberto Mantovani
- Istituto Clinico Humanitas, Rozzano Milan, and Institute of General Pathology, Faculty of Medicine, University of Milan, Italy
| | - Kenneth B. M. Reid
- Medical Research Council Immunochemistry Unit, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, U. K
| | - Uday Kishore
- Institute of Medical Microbiology, Faculty of Medicine, Justus-Liebig-University, Frankfurter Strasse 107, 35392 Giessen, Germany
- Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, U. K
- Corresponding author. Phone: +44-1865-222325. Fax: +44-1865-222402; +49-641-9941259.
| | - Mihaela S. Kojouharova
- Department of Biochemistry, Sofia University, St. Kliment Ohridski, 8 Dragan Tsankov Street, Sofia 1164, Bulgaria
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