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Haslund-Gourley BS, Hou J, Woloszczuk K, Horn EJ, Dempsey G, Haddad EK, Wigdahl B, Comunale MA. Host glycosylation of immunoglobulins impairs the immune response to acute Lyme disease. EBioMedicine 2024; 100:104979. [PMID: 38266555 PMCID: PMC10818078 DOI: 10.1016/j.ebiom.2024.104979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 01/02/2024] [Accepted: 01/09/2024] [Indexed: 01/26/2024] Open
Abstract
BACKGROUND Lyme disease is caused by the bacteria Borreliella burgdorferi sensu lato (Bb) transmitted to humans from the bite of an infected Ixodes tick. Current diagnostics for Lyme disease are insensitive at the early disease stage and they cannot differentiate between active infections and people with a recent history of antibiotic-treated Lyme disease. METHODS Machine learning technology was utilized to improve the prediction of acute Lyme disease and identify sialic acid and galactose sugar structures (N-glycans) on immunoglobulins associated specifically at time points during acute Lyme disease time. A plate-based approach was developed to analyze sialylated N-glycans associated with anti-Bb immunoglobulins. This multiplexed approach quantitates the abundance of Bb-specific IgG and the associated sialic acid, yielding an accuracy of 90% in a powered study. FINDINGS It was demonstrated that immunoglobulin sialic acid levels increase during acute Lyme disease and following antibiotic therapy and a 3-month convalescence, the sialic acid level returned to that found in healthy control subjects (p < 0.001). Furthermore, the abundance of sialic acid on Bb-specific IgG during acute Lyme disease impaired the host's ability to combat Lyme disease via lymphocytic receptor FcγRIIIa signaling. After enzymatically removing the sialic acid present on Bb-specific antibodies, the induction of cytotoxicity from acute Lyme disease patient antigen-specific IgG was significantly improved. INTERPRETATION Taken together, Bb-specific immunoglobulins contain increased sialylation which impairs the host immune response during acute Lyme disease. Furthermore, this Bb-specific immunoglobulin sialyation found in acute Lyme disease begins to resolve following antibiotic therapy and convalescence. FUNDING Funding for this study was provided by the Coulter-Drexel Translational Research Partnership Program as well as from a Faculty Development Award from the Drexel University College of Medicine Institute for Molecular Medicine and Infectious Disease and the Department of Microbiology and Immunology.
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Affiliation(s)
- Benjamin S Haslund-Gourley
- Department of Microbiology and Immunology and the Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Jintong Hou
- Department of Microbiology and Immunology and the Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Kyra Woloszczuk
- Department of Microbiology and Immunology and the Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | | | - George Dempsey
- East Hampton Family Medicine, East Hampton North, New York, USA
| | - Elias K Haddad
- Department of Microbiology and Immunology and the Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Brian Wigdahl
- Department of Microbiology and Immunology and the Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA
| | - Mary Ann Comunale
- Department of Microbiology and Immunology and the Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA.
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Klukowski P, Damberger FF, Allain FHT, Iwai H, Kadavath H, Ramelot TA, Montelione GT, Riek R, Güntert P. The 100-protein NMR spectra dataset: A resource for biomolecular NMR data analysis. Sci Data 2024; 11:30. [PMID: 38177162 PMCID: PMC10767026 DOI: 10.1038/s41597-023-02879-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 12/22/2023] [Indexed: 01/06/2024] Open
Abstract
Multidimensional NMR spectra are the basis for studying proteins by NMR spectroscopy and crucial for the development and evaluation of methods for biomolecular NMR data analysis. Nevertheless, in contrast to derived data such as chemical shift assignments in the BMRB and protein structures in the PDB databases, this primary data is in general not publicly archived. To change this unsatisfactory situation, we present a standardized set of solution NMR data comprising 1329 2-4-dimensional NMR spectra and associated reference (chemical shift assignments, structures) and derived (peak lists, restraints for structure calculation, etc.) annotations. With the 100-protein NMR spectra dataset that was originally compiled for the development of the ARTINA deep learning-based spectra analysis method, 100 protein structures can be reproduced from their original experimental data. The 100-protein NMR spectra dataset is expected to help the development of computational methods for NMR spectroscopy, in particular machine learning approaches, and enable consistent and objective comparisons of these methods.
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Affiliation(s)
- Piotr Klukowski
- Institute of Molecular Physical Science, ETH Zurich, 8093, Zurich, Switzerland.
| | - Fred F Damberger
- Institute of Biochemistry, ETH Zurich, 8093, Zurich, Switzerland
| | | | - Hideo Iwai
- Institute of Biotechnology, University of Helsinki, 00100, Helsinki, Finland
| | | | - Theresa A Ramelot
- Department of Chemistry and Chemical Biology, and Center for Biotechnology and Interdisciplinary Sciences, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Gaetano T Montelione
- Department of Chemistry and Chemical Biology, and Center for Biotechnology and Interdisciplinary Sciences, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Roland Riek
- Institute of Molecular Physical Science, ETH Zurich, 8093, Zurich, Switzerland.
| | - Peter Güntert
- Institute of Molecular Physical Science, ETH Zurich, 8093, Zurich, Switzerland.
- Institute of Biophysical Chemistry, Goethe University, 60438, Frankfurt am Main, Germany.
- Department of Chemistry, Tokyo Metropolitan University, Hachioji, 192-0397, Tokyo, Japan.
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Zhang S, He Y, Wu Z, Wang M, Jia R, Zhu D, Liu M, Zhao X, Yang Q, Wu Y, Zhang S, Huang J, Ou X, Gao Q, Sun D, Zhang L, Yu Y, Chen S, Cheng A. Secretory pathways and multiple functions of nonstructural protein 1 in flavivirus infection. Front Immunol 2023; 14:1205002. [PMID: 37520540 PMCID: PMC10372224 DOI: 10.3389/fimmu.2023.1205002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 06/27/2023] [Indexed: 08/01/2023] Open
Abstract
The genus Flavivirus contains a wide variety of viruses that cause severe disease in humans, including dengue virus, yellow fever virus, Zika virus, West Nile virus, Japanese encephalitis virus and tick-borne encephalitis virus. Nonstructural protein 1 (NS1) is a glycoprotein that encodes a 352-amino-acid polypeptide and has a molecular weight of 46-55 kDa depending on its glycosylation status. NS1 is highly conserved among multiple flaviviruses and occurs in distinct forms, including a dimeric form within the endoplasmic reticulum, a cell-associated form on the plasma membrane, or a secreted hexameric form (sNS1) trafficked to the extracellular matrix. Intracellular dimeric NS1 interacts with other NSs to participate in viral replication and virion maturation, while extracellular sNS1 plays a critical role in immune evasion, flavivirus pathogenesis and interactions with natural vectors. In this review, we provide an overview of recent research progress on flavivirus NS1, including research on the structural details, the secretory pathways in mammalian and mosquito cells and the multiple functions in viral replication, immune evasion, pathogenesis and interaction with natural hosts, drawing together the previous data to determine the properties of this protein.
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Affiliation(s)
- Senzhao Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Yu He
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Zhen Wu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Mingshu Wang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Renyong Jia
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Dekang Zhu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Mafeng Liu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Xinxin Zhao
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Qiao Yang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Ying Wu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Shaqiu Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Juan Huang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Xumin Ou
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Qun Gao
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Di Sun
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Ling Zhang
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Yanling Yu
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
| | - Shun Chen
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
| | - Anchun Cheng
- Research Center of Avian Disease, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan, China
- Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Chengdu, Sichuan, China
- Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People’s Republic of China, Chengdu, China
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Stevenson B, Brissette CA. Erp and Rev Adhesins of the Lyme Disease Spirochete's Ubiquitous cp32 Prophages Assist the Bacterium during Vertebrate Infection. Infect Immun 2023; 91:e0025022. [PMID: 36853019 PMCID: PMC10016077 DOI: 10.1128/iai.00250-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
Almost all spirochetes in the genus Borrelia (sensu lato) naturally contain multiple variants of closely related prophages. In the Lyme disease borreliae, these prophages are maintained as circular episomes that are called circular plasmid 32 kb (cp32s). The cp32s of Lyme agents are particularly unique in that they encode two distinct families of lipoproteins, namely, Erp and Rev, that are expressed on the bacterial outer surface during infection of vertebrate hosts. All identified functions of those outer surface proteins involve interactions between the spirochetes and host molecules, as follows: Erp proteins bind plasmin(ogen), laminin, glycosaminoglycans, and/or components of complement and Rev proteins bind fibronectin. Thus, cp32 prophages provide their bacterial hosts with surface proteins that can enhance infection processes, thereby facilitating their own survival. Horizontal transfer via bacteriophage particles increases the spread of beneficial alleles and creates diversity among Erp and Rev proteins.
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Affiliation(s)
- Brian Stevenson
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky, Lexington, Kentucky, USA
- Department of Entomology, University of Kentucky, Lexington, Kentucky, USA
| | - Catherine A. Brissette
- Department of Biomedical Sciences, University of North Dakota, Grand Forks, North Dakota, USA
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5
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Outer surface protein E (OspE) mediates Borrelia burgdorferi sensu stricto strain-specific complement evasion in the eastern fence lizard, Sceloporus undulatus. Ticks Tick Borne Dis 2023; 14:102081. [PMID: 36403322 DOI: 10.1016/j.ttbdis.2022.102081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 10/31/2022] [Accepted: 11/01/2022] [Indexed: 11/11/2022]
Abstract
In North America, Lyme disease is primarily caused by the spirochetal bacterium Borrelia burgdorferi sensu stricto (Bb), which is transmitted between multiple vertebrate hosts and ixodid ticks, and is a model commonly used to study host-pathogen interactions. While Bb is consistently observed in its mammalian and avian reservoirs, the bacterium is rarely isolated from North American reptiles. Two closely related lizard species, the eastern fence lizard (Sceloporus undulatus) and the western fence lizard (Sceloporus occidentalis), are examples of reptiles parasitized by Ixodes ticks. Vertebrates are known to generate complement as an innate defense mechanism, which can be activated before Bb disseminate to distal tissues. Complement from western fence lizards has proven lethal against one Bb strain, implying the role of complement in making those lizards unable to serve as hosts to Bb. However, Bb DNA is occasionally identified in distal tissues of field-collected eastern fence lizards, suggesting some Bb strains may overcome complement-mediated clearance in these lizards. These findings raise questions regarding the role of complement and its impact on Bb interactions with North American lizards. In this study, we found Bb seropositivity in a small population of wild-caught eastern fence lizards and observed Bb strain-specific survivability in lizard sera. We also found that a Bb outer surface protein, OspE, from Bb strains viable in sera, promotes lizard serum survivability and binds to a complement inhibitor, factor H, from eastern fence lizards. Our data thus identify bacterial and host determinants of eastern fence lizard complement evasion, providing insights into the role of complement influencing Bb interactions with North American lizards.
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Garrigues RJ, Thomas S, Leong JM, Garcia BL. Outer surface lipoproteins from the Lyme disease spirochete exploit the molecular switch mechanism of the complement protease C1s. J Biol Chem 2022; 298:102557. [PMID: 36183830 PMCID: PMC9637899 DOI: 10.1016/j.jbc.2022.102557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 09/23/2022] [Accepted: 09/26/2022] [Indexed: 10/14/2022] Open
Abstract
Proteolytic cascades comprise several important physiological systems, including a primary arm of innate immunity called the complement cascade. To safeguard against complement-mediated attack, the etiologic agent of Lyme disease, Borreliella burgdorferi, produces numerous outer surface-localized lipoproteins that contribute to successful complement evasion. Recently, we discovered a pair of B. burgdorferi surface lipoproteins of the OspEF-related protein family-termed ElpB and ElpQ-that inhibit antibody-mediated complement activation. In this study, we investigate the molecular mechanism of ElpB and ElpQ complement inhibition using an array of biochemical and biophysical approaches. In vitro assays of complement activation show that an independently folded homologous C-terminal domain of each Elp protein maintains full complement inhibitory activity and selectively inhibits the classical pathway. Using binding assays and complement component C1s enzyme assays, we show that binding of Elp proteins to activated C1s blocks complement component C4 cleavage by competing with C1s-C4 binding without occluding the active site. C1s-mediated C4 cleavage is dependent on activation-induced binding sites, termed exosites. To test whether these exosites are involved in Elp-C1s binding, we performed site-directed mutagenesis, which showed that ElpB and ElpQ binding require C1s residues in the anion-binding exosite located on the serine protease domain of C1s. Based on these results, we propose a model whereby ElpB and ElpQ exploit activation-induced conformational changes that are normally important for C1s-mediated C4 cleavage. Our study expands the known complement evasion mechanisms of microbial pathogens and reveals a novel molecular mechanism for selective C1s inhibition by Lyme disease spirochetes.
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7
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Kogan K, Haapasalo K, Kotila T, Moore R, Lappalainen P, Goldman A, Meri T. Mechanism of Borrelia immune evasion by FhbA-related proteins. PLoS Pathog 2022; 18:e1010338. [PMID: 35303742 PMCID: PMC8967061 DOI: 10.1371/journal.ppat.1010338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/30/2022] [Accepted: 02/03/2022] [Indexed: 11/18/2022] Open
Abstract
Immune evasion facilitates survival of Borrelia, leading to infections like relapsing fever and Lyme disease. Important mechanism for complement evasion is acquisition of the main host complement inhibitor, factor H (FH). By determining the 2.2 Å crystal structure of Factor H binding protein A (FhbA) from Borrelia hermsii in complex with FH domains 19–20, combined with extensive mutagenesis, we identified the structural mechanism by which B. hermsii utilizes FhbA in immune evasion. Moreover, structure-guided sequence database analysis identified a new family of FhbA-related immune evasion molecules from Lyme disease and relapsing fever Borrelia. Conserved FH-binding mechanism within the FhbA-family was verified by analysis of a novel FH-binding protein from B. duttonii. By sequence analysis, we were able to group FH-binding proteins of Borrelia into four distinct phyletic types and identified novel putative FH-binding proteins. The conserved FH-binding mechanism of the FhbA-related proteins could aid in developing new approaches to inhibit virulence and complement resistance in Borrelia. Relapsing fever and Lyme Disease are infectious diseases caused by borrelia bacteria. Relapsing fever occurs sporadically worldwide, whereas distribution of Lyme Disease is restricted to the Northern Hemisphere. Both infections are transmitted to humans by blood eating ticks or lice. These infections are often difficult to diagnose due to nonspecific symptoms. To be able to cause infection, borrelia must circumvent the human immune responses. Here we describe a mechanism, how borrelia bacteria protect themselves in the human host by utilizing host proteins. By using X-ray crystallography, we solved the structure of an outer membrane protein FhbA from a relapsing fever causing borreliae, Borrelia hermsii, in complex with human complement regulator factor H. FhbA has a unique alpha-helical fold that has not been reported earlier. The structure of the complex revealed how FhbA binds factor H in a very specific manner. Factor H bound to FhbA on the surface of borrelia protects bacteria from the complement system and lysis. Based on the structure, we performed structure-guided sequence database analysis, which suggests that similar proteins are present in all relapsing fever causing borrelia and possibly in some Lyme disease agents.
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Affiliation(s)
- Konstantin Kogan
- HiLife Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Karita Haapasalo
- Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
| | - Tommi Kotila
- HiLife Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Robin Moore
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Pekka Lappalainen
- HiLife Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Adrian Goldman
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
- Astbury Center for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Taru Meri
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
- * E-mail:
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Xu X, Marffy ALL, Keightley A, McCarthy AJ, Geisbrecht BV. Group B Streptococcus Surface Protein β: Structural Characterization of a Complement Factor H-Binding Motif and Its Contribution to Immune Evasion. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:1232-1247. [PMID: 35110419 PMCID: PMC8881398 DOI: 10.4049/jimmunol.2101078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 12/10/2021] [Indexed: 11/19/2022]
Abstract
The β protein from group B Streptococcus (GBS) is a ∼132-kDa, cell-surface exposed molecule that binds to multiple host-derived ligands, including complement factor H (FH). Many details regarding this interaction and its significance to immune evasion by GBS remain unclear. In this study, we identified a three-helix bundle domain within the C-terminal half of the B75KN region of β as the major FH-binding determinant and determined its crystal structure at 2.5 Å resolution. Analysis of this structure suggested a role in FH binding for a loop region connecting helices α1 and α2, which we confirmed by mutagenesis and direct binding studies. Using a combination of protein cross-linking and mass spectrometry, we observed that B75KN bound to complement control protein (CCP)3 and CCP4 domains of FH. Although this binding site lies within a complement regulatory region of FH, we determined that FH bound by β retained its decay acceleration and cofactor activities. Heterologous expression of β by Lactococcus lactis resulted in recruitment of FH to the bacterial surface and a significant reduction of C3b deposition following exposure to human serum. Surprisingly, we found that FH binding by β was not required for bacterial resistance to phagocytosis by neutrophils or killing of bacteria by whole human blood. However, loss of the B75KN region significantly diminished bacterial survival in both assays. Although our results show that FH recruited to the bacterial surface through a high-affinity interaction maintains key complement-regulatory functions, they raise questions about the importance of FH binding to immune evasion by GBS as a whole.
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Affiliation(s)
- Xin Xu
- Department of Biochemistry & Molecular Biophysics, Kansas State University; Manhattan, KS U.S.A
| | - Alexander L. Lewis Marffy
- Department of Infectious Diseases, Section of Molecular Microbiology, MRC Centre for Molecular Bacteriology & Infection, Imperial College London; London, U.K
| | - Andrew Keightley
- Department of Opthamology, School of Medicine, University of Missouri-Kansas City; Kansas City, MO U.S.A
| | - Alex J. McCarthy
- Department of Infectious Diseases, Section of Molecular Microbiology, MRC Centre for Molecular Bacteriology & Infection, Imperial College London; London, U.K
| | - Brian V. Geisbrecht
- Department of Biochemistry & Molecular Biophysics, Kansas State University; Manhattan, KS U.S.A.,To whom correspondence should be addressed: Brian V. Geisbrecht, Ph.D., Kansas State University, 141 Chalmers Hall, 1711 Claflin Road, Manhattan, KS 66506, PH: 785.532.3154,
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Cortes C, Desler C, Mazzoli A, Chen JY, Ferreira VP. The role of properdin and Factor H in disease. Adv Immunol 2022; 153:1-90. [PMID: 35469595 DOI: 10.1016/bs.ai.2021.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The complement system consists of three pathways (alternative, classical, and lectin) that play a fundamental role in immunity and homeostasis. The multifunctional role of the complement system includes direct lysis of pathogens, tagging pathogens for phagocytosis, promotion of inflammatory responses to control infection, regulation of adaptive cellular immune responses, and removal of apoptotic/dead cells and immune complexes from circulation. A tight regulation of the complement system is essential to avoid unwanted complement-mediated damage to the host. This regulation is ensured by a set of proteins called complement regulatory proteins. Deficiencies or malfunction of these regulatory proteins may lead to pro-thrombotic hematological diseases, renal and ocular diseases, and autoimmune diseases, among others. This review focuses on the importance of two complement regulatory proteins of the alternative pathway, Factor H and properdin, and their role in human diseases with an emphasis on: (a) characterizing the main mechanism of action of Factor H and properdin in regulating the complement system and protecting the host from complement-mediated attack, (b) describing the dysregulation of the alternative pathway as a result of deficiencies, or mutations, in Factor H and properdin, (c) outlining the clinical findings, management and treatment of diseases associated with mutations and deficiencies in Factor H, and (d) defining the unwanted and inadequate functioning of properdin in disease, through a discussion of various experimental research findings utilizing in vitro, mouse and human models.
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Affiliation(s)
- Claudio Cortes
- Department of Foundational Medical Studies, Oakland University William Beaumont School of Medicine, Rochester, MI, United States.
| | - Caroline Desler
- Oakland University William Beaumont School of Medicine, Rochester, MI, United States
| | - Amanda Mazzoli
- Oakland University William Beaumont School of Medicine, Rochester, MI, United States
| | - Jin Y Chen
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States
| | - Viviana P Ferreira
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH, United States.
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Moore SR, Menon SS, Cortes C, Ferreira VP. Hijacking Factor H for Complement Immune Evasion. Front Immunol 2021; 12:602277. [PMID: 33717083 PMCID: PMC7947212 DOI: 10.3389/fimmu.2021.602277] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 01/15/2021] [Indexed: 12/15/2022] Open
Abstract
The complement system is an essential player in innate and adaptive immunity. It consists of three pathways (alternative, classical, and lectin) that initiate either spontaneously (alternative) or in response to danger (all pathways). Complement leads to numerous outcomes detrimental to invaders, including direct killing by formation of the pore-forming membrane attack complex, recruitment of immune cells to sites of invasion, facilitation of phagocytosis, and enhancement of cellular immune responses. Pathogens must overcome the complement system to survive in the host. A common strategy used by pathogens to evade complement is hijacking host complement regulators. Complement regulators prevent attack of host cells and include a collection of membrane-bound and fluid phase proteins. Factor H (FH), a fluid phase complement regulatory protein, controls the alternative pathway (AP) both in the fluid phase of the human body and on cell surfaces. In order to prevent complement activation and amplification on host cells and tissues, FH recognizes host cell-specific polyanionic markers in combination with complement C3 fragments. FH suppresses AP complement-mediated attack by accelerating decay of convertases and by helping to inactivate C3 fragments on host cells. Pathogens, most of which do not have polyanionic markers, are not recognized by FH. Numerous pathogens, including certain bacteria, viruses, protozoa, helminths, and fungi, can recruit FH to protect themselves against host-mediated complement attack, using either specific receptors and/or molecular mimicry to appear more like a host cell. This review will explore pathogen complement evasion mechanisms involving FH recruitment with an emphasis on: (a) characterizing the structural properties and expression patterns of pathogen FH binding proteins, as well as other strategies used by pathogens to capture FH; (b) classifying domains of FH important in pathogen interaction; and (c) discussing existing and potential treatment strategies that target FH interactions with pathogens. Overall, many pathogens use FH to avoid complement attack and appreciating the commonalities across these diverse microorganisms deepens the understanding of complement in microbiology.
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Affiliation(s)
- Sara R Moore
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH, United States
| | - Smrithi S Menon
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH, United States
| | - Claudio Cortes
- Department of Foundational Medical Sciences, Oakland University William Beaumont School of Medicine, Rochester, MI, United States
| | - Viviana P Ferreira
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH, United States
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11
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Cole GB, Bateman TJ, Moraes TF. The surface lipoproteins of gram-negative bacteria: Protectors and foragers in harsh environments. J Biol Chem 2021; 296:100147. [PMID: 33277359 PMCID: PMC7857515 DOI: 10.1074/jbc.rev120.008745] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 12/02/2020] [Accepted: 12/04/2020] [Indexed: 11/06/2022] Open
Abstract
Gram-negative pathogens are enveloped by an outer membrane that serves as a double-edged sword: On the one hand, it provides a layer of protection for the bacterium from environmental insults, including other bacteria and the host immune system. On the other hand, it restricts movement of vital nutrients into the cell and provides a plethora of antigens that can be detected by host immune systems. One strategy used to overcome these limitations is the decoration of the outer surface of gram-negative bacteria with proteins tethered to the outer membrane through a lipid anchor. These surface lipoproteins (SLPs) fulfill critical roles in immune evasion and nutrient acquisition, but as more bacterial genomes are sequenced, we are beginning to discover their prevalence and their different roles and mechanisms and importantly how we can exploit them as antimicrobial targets. This review will focus on representative SLPs that gram-negative bacteria use to overcome host innate immunity, specifically the areas of nutritional immunity and complement system evasion. We elaborate on the structures of some notable SLPs required for binding target molecules in hosts and how this information can be used alongside bioinformatics to understand mechanisms of binding and in the discovery of new SLPs. This information provides a foundation for the development of therapeutics and the design of vaccine antigens.
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Affiliation(s)
- Gregory B Cole
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Thomas J Bateman
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Trevor F Moraes
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada.
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12
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Samuels DS, Lybecker MC, Yang XF, Ouyang Z, Bourret TJ, Boyle WK, Stevenson B, Drecktrah D, Caimano MJ. Gene Regulation and Transcriptomics. Curr Issues Mol Biol 2020; 42:223-266. [PMID: 33300497 DOI: 10.21775/cimb.042.223] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Borrelia (Borreliella) burgdorferi, along with closely related species, is the etiologic agent of Lyme disease. The spirochete subsists in an enzootic cycle that encompasses acquisition from a vertebrate host to a tick vector and transmission from a tick vector to a vertebrate host. To adapt to its environment and persist in each phase of its enzootic cycle, B. burgdorferi wields three systems to regulate the expression of genes: the RpoN-RpoS alternative sigma factor cascade, the Hk1/Rrp1 two-component system and its product c-di-GMP, and the stringent response mediated by RelBbu and DksA. These regulatory systems respond to enzootic phase-specific signals and are controlled or fine- tuned by transcription factors, including BosR and BadR, as well as small RNAs, including DsrABb and Bb6S RNA. In addition, several other DNA-binding and RNA-binding proteins have been identified, although their functions have not all been defined. Global changes in gene expression revealed by high-throughput transcriptomic studies have elucidated various regulons, albeit technical obstacles have mostly limited this experimental approach to cultivated spirochetes. Regardless, we know that the spirochete, which carries a relatively small genome, regulates the expression of a considerable number of genes required for the transitions between the tick vector and the vertebrate host as well as the adaptation to each.
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Affiliation(s)
- D Scott Samuels
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Meghan C Lybecker
- Department of Biology, University of Colorado, Colorado Springs, CO 80918, USA
| | - X Frank Yang
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Zhiming Ouyang
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Travis J Bourret
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE, 68105 USA
| | - William K Boyle
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE, 68105 USA
| | - Brian Stevenson
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky School of Medicine, Lexington, KY 40536, USA
| | - Dan Drecktrah
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Melissa J Caimano
- Departments of Medicine, Pediatrics, and Molecular Biology and Biophysics, UConn Health, Farmington, CT, USA
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13
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Dulipati V, Meri S, Panelius J. Complement evasion strategies of Borrelia burgdorferi sensu lato. FEBS Lett 2020; 594:2645-2656. [PMID: 32748966 DOI: 10.1002/1873-3468.13894] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 07/15/2020] [Accepted: 07/22/2020] [Indexed: 01/12/2023]
Abstract
Borreliosis (Lyme disease) is a spirochetal disease caused by the species complex of Borrelia burgdorferi transmitted by Ixodes spp. ticks. Recorded to be the most common tick-borne disease in the world, the last two decades have seen an increase in disease incidence and distribution, exceeding 360 000 cases in Europe alone. If untreated, infection may cause skin symptoms, arthritis, and neurological or cardiac complications. Borrelia spirochetes have developed strategies to evade the mammalian host immune system. These include the complement system, which is an important first-line defense mechanism against invading microbes. To evade the complement, spirochetes bind soluble complement regulators factor H (FH), factor H-like protein, and C4bp to their outer surfaces. B. burgdorferi spirochetes can inhibit the classical pathway of complement by the outer surface protein (Osp) BBK32, which blocks the activation of the C1 complex, composed of C1q, C1r, and C1s. The FH-binding proteins of borreliae include Osps OspE, CspA, and CspZ. Following repeated infections, antibodies against these proteins develop and may provide functional immunity against borreliosis. This review discusses critical immune evasion strategies, focusing on complement evasion by borreliae.
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Affiliation(s)
- Vinaya Dulipati
- Department of Bacteriology and Immunology and Translational Immunology Research Program, University of Helsinki, Helsinki, Finland
| | - Seppo Meri
- Department of Bacteriology and Immunology and Translational Immunology Research Program, University of Helsinki, Helsinki, Finland.,HUSLAB, Helsinki University Hospital, Helsinki, Finland
| | - Jaana Panelius
- Department of Dermatology and Allergology, University of Helsinki, Helsinki University Hospital, Helsinki, Finland
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14
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Skare JT, Garcia BL. Complement Evasion by Lyme Disease Spirochetes. Trends Microbiol 2020; 28:889-899. [PMID: 32482556 DOI: 10.1016/j.tim.2020.05.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 04/26/2020] [Accepted: 05/05/2020] [Indexed: 01/12/2023]
Abstract
The complement system is an ancient arm of the innate immune system that plays important roles in pathogen recognition and elimination. Upon activation by microbes, complement opsonizes bacterial surfaces, recruits professional phagocytes, and causes bacteriolysis. Borreliella species are spirochetal bacteria that are transmitted to vertebrate hosts via infected Ixodes ticks and are the etiologic agents of Lyme disease. Pathogens that traffic in blood and other body fluids, like Borreliella, have evolved means to evade complement. Lyme disease spirochetes interfere with complement by producing a small arsenal of outer-surface lipoproteins that bind host complement components and manipulate their native activities. Here we review the current landscape of complement evasion by Lyme disease spirochetes and provide an update on recent discoveries.
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Affiliation(s)
- Jon T Skare
- Department of Microbial Pathogenesis and Immunology, College of Medicine, Texas A&M University, Bryan/College Station, TX, USA.
| | - Brandon L Garcia
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC, USA.
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15
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Macleod OJS, Bart JM, MacGregor P, Peacock L, Savill NJ, Hester S, Ravel S, Sunter JD, Trevor C, Rust S, Vaughan TJ, Minter R, Mohammed S, Gibson W, Taylor MC, Higgins MK, Carrington M. A receptor for the complement regulator factor H increases transmission of trypanosomes to tsetse flies. Nat Commun 2020; 11:1326. [PMID: 32165615 PMCID: PMC7067766 DOI: 10.1038/s41467-020-15125-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 02/15/2020] [Indexed: 11/09/2022] Open
Abstract
Persistent pathogens have evolved to avoid elimination by the mammalian immune system including mechanisms to evade complement. Infections with African trypanosomes can persist for years and cause human and animal disease throughout sub-Saharan Africa. It is not known how trypanosomes limit the action of the alternative complement pathway. Here we identify an African trypanosome receptor for mammalian factor H, a negative regulator of the alternative pathway. Structural studies show how the receptor binds ligand, leaving inhibitory domains of factor H free to inactivate complement C3b deposited on the trypanosome surface. Receptor expression is highest in developmental stages transmitted to the tsetse fly vector and those exposed to blood meals in the tsetse gut. Receptor gene deletion reduced tsetse infection, identifying this receptor as a virulence factor for transmission. This demonstrates how a pathogen evolved a molecular mechanism to increase transmission to an insect vector by exploitation of a mammalian complement regulator.
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Affiliation(s)
- Olivia J S Macleod
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Jean-Mathieu Bart
- Intertryp, IRD, Cirad, University of Montpellier, Montpellier, France
| | - Paula MacGregor
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Lori Peacock
- School of Biological Sciences, University of Bristol, Bristol, BS8 1UG, UK
| | - Nicholas J Savill
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh, EH9 3JT, UK
| | - Svenja Hester
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Sophie Ravel
- Intertryp, IRD, Cirad, University of Montpellier, Montpellier, France
| | - Jack D Sunter
- Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, UK
| | - Camilla Trevor
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
- Department of Antibody Discovery and Protein Engineering, AstraZeneca R&D, Granta Park, Cambridge, CB21 6GH, UK
| | - Steven Rust
- Department of Antibody Discovery and Protein Engineering, AstraZeneca R&D, Granta Park, Cambridge, CB21 6GH, UK
| | - Tristan J Vaughan
- Department of Antibody Discovery and Protein Engineering, AstraZeneca R&D, Granta Park, Cambridge, CB21 6GH, UK
| | - Ralph Minter
- Department of Antibody Discovery and Protein Engineering, AstraZeneca R&D, Granta Park, Cambridge, CB21 6GH, UK
| | - Shabaz Mohammed
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Wendy Gibson
- School of Biological Sciences, University of Bristol, Bristol, BS8 1UG, UK
| | - Martin C Taylor
- Faculty of Infectious and Tropical diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Matthew K Higgins
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK.
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16
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Lin YP, Frye AM, Nowak TA, Kraiczy P. New Insights Into CRASP-Mediated Complement Evasion in the Lyme Disease Enzootic Cycle. Front Cell Infect Microbiol 2020; 10:1. [PMID: 32083019 PMCID: PMC7002432 DOI: 10.3389/fcimb.2020.00001] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 01/06/2020] [Indexed: 12/23/2022] Open
Abstract
Lyme disease (LD), which is caused by genospecies of the Borrelia burgdorferi sensu lato complex, is the most common vector-borne disease in the Northern hemisphere. Spirochetes are transmitted by Ixodes ticks and maintained in diverse vertebrate animal hosts. Following tick bite, spirochetes initially establish a localized infection in the skin. However, they may also disseminate hematogenously to several distal sites, including heart, joints, or the CNS. Because they need to survive in diverse microenvironments, from tick vector to mammalian hosts, spirochetes have developed multiple strategies to combat the numerous host defense mechanisms. One of these strategies includes the production of a number of complement-regulator acquiring surface proteins (CRASPs) which encompass CspA, CspZ, and OspE paralogs to blunt the complement pathway. These proteins are capable of preventing complement activation on the spirochete surface by binding to complement regulator Factor H. The genes encoding these CRASPs differ in their expression patterns during the tick-to-host infection cycle, implying that these proteins may exhibit different functions during infection. This review summarizes the recent published reports which investigated the roles that each of these molecules plays in conferring tick-borne transmission and dissemination in vertebrate hosts. These findings offer novel mechanistic insights into LD pathobiology and may facilitate the identification of new targets for preventive strategies against Lyme borreliosis.
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Affiliation(s)
- Yi-Pin Lin
- Department of Biomedical Sciences, State University of New York at Albany, Albany, NY, United States.,Division of Infectious Diseases, New York State Department of Health, Wadsworth Center, Albany, NY, United States
| | - Amber M Frye
- Department of Biomedical Sciences, State University of New York at Albany, Albany, NY, United States.,Division of Infectious Diseases, New York State Department of Health, Wadsworth Center, Albany, NY, United States
| | - Tristan A Nowak
- Department of Biomedical Sciences, State University of New York at Albany, Albany, NY, United States.,Division of Infectious Diseases, New York State Department of Health, Wadsworth Center, Albany, NY, United States
| | - Peter Kraiczy
- Institute of Medical Microbiology and Infection Control, University Hospital, Goethe University Frankfurt, Frankfurt, Germany
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17
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Valoti E, Alberti M, Iatropoulos P, Piras R, Mele C, Breno M, Cremaschi A, Bresin E, Donadelli R, Alizzi S, Amoroso A, Benigni A, Remuzzi G, Noris M. Rare Functional Variants in Complement Genes and Anti-FH Autoantibodies-Associated aHUS. Front Immunol 2019; 10:853. [PMID: 31118930 PMCID: PMC6504697 DOI: 10.3389/fimmu.2019.00853] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 04/02/2019] [Indexed: 01/06/2023] Open
Abstract
Atypical hemolytic uremic syndrome (aHUS) is a rare disease characterized by microangiopathic hemolytic anemia, thrombocytopenia and renal failure. It is caused by genetic or acquired defects of the complement alternative pathway. Factor H autoantibodies (anti-FHs) have been reported in 10% of aHUS patients and are associated with the deficiency of factor H-related 1 (FHR1). However, FHR1 deficiency is not enough to cause aHUS, since it is also present in about 5% of Caucasian healthy subjects. In this study we evaluated the prevalence of genetic variants in CFH, CD46, CFI, CFB, C3, and THBD in aHUS patients with anti-FHs, using healthy subjects with FHR1 deficiency, here defined “supercontrols,” as a reference group. “Supercontrols” are more informative than general population because they share at least one risk factor (FHR1 deficiency) with aHUS patients. We analyzed anti-FHs in 305 patients and 30 were positive. The large majority were children (median age: 7.7 [IQR, 6.6–9.9] years) and 83% lacked FHR1 (n = 25, cases) due to the homozygous CFHR3-CFHR1 deletion (n = 20), or the compound heterozygous CFHR3-CFHR1 and CFHR1-CFHR4 deletions (n = 4), or the heterozygous CFHR3-CFHR1 deletion combined with a frameshift mutation in CFHR1 that generates a premature stop codon (n = 1). Of the 960 healthy adult subjects 48 had the FHR1 deficiency (“supercontrols”). Rare likely pathogenetic variants in CFH, THBD, and C3 were found in 24% of cases (n = 6) compared to 2.1% of the “supercontrols” (P-value = 0.005). We also found that the CFH H3 and the CD46GGAAC haplotypes are not associated with anti-FHs aHUS, whereas these haplotypes are enriched in aHUS patients without anti-FHs, which highlights the differences in the genetic basis of the two forms of the disease. Finally, we confirm that common infections are environmental factors that contribute to the development of anti-FHs aHUS in genetically predisposed individuals, which fits with the sharp peak of incidence during scholar-age. Further studies are needed to fully elucidate the complex genetic and environmental factors underlying anti-FHs aHUS and to establish whether the combination of anti-FHs with likely pathogenetic variants or other risk factors influences disease outcome and response to therapies.
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Affiliation(s)
- Elisabetta Valoti
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Marta Alberti
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Paraskevas Iatropoulos
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Rossella Piras
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Caterina Mele
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Matteo Breno
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Alessandra Cremaschi
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Elena Bresin
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Roberta Donadelli
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Silvia Alizzi
- Azienda Ospedaliera-Universitaria, Città della Salute e della Scienza and Department of Medical Sciences, University of Turin, Turin, Italy
| | - Antonio Amoroso
- Azienda Ospedaliera-Universitaria, Città della Salute e della Scienza and Department of Medical Sciences, University of Turin, Turin, Italy
| | - Ariela Benigni
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
| | - Giuseppe Remuzzi
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy.,'L. Sacco' Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy
| | - Marina Noris
- Clinical Research Center for Rare Diseases 'Aldo e Cele Daccò', Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Bergamo, Italy
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18
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Brangulis K, Akopjana I, Petrovskis I, Kazaks A, Kraiczy P, Tars K. Crystal structure of the membrane attack complex assembly inhibitor BGA71 from the Lyme disease agent Borrelia bavariensis. Sci Rep 2018; 8:11286. [PMID: 30050126 PMCID: PMC6062577 DOI: 10.1038/s41598-018-29651-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/14/2018] [Indexed: 11/09/2022] Open
Abstract
Borrelia (B.) bavariensis, B. burgdorferi, B. afzelii, B. garinii, B. spielmanii, and B. mayonii are the causative agents in Lyme disease. Lyme disease spirochetes reside in infected Ixodes ticks and are transferred to mammalian hosts during tick feeding. Once transmitted, spirochetes must overcome the first line of defense of the innate immune system either by binding complement regulators or by terminating the formation of the membrane attack complex (MAC). In B. bavariensis, the proteins BGA66 and BGA71 inhibit complement activation by interacting with the late complement components C7, C8, and C9, as well as with the formed MAC. In this study, we have determined the crystal structure of the potent MAC inhibitor BGA71 at 2.9 Ǻ resolution. The structure revealed a cysteine cross-linked homodimer. Based on the crystal structure of BGA71 and the structure-based sequence alignment with CspA from B. burgdorferi, we have proposed a potential binding site for C7 and C9, both of which are constituents of the formed MAC. Our results shed light on the molecular mechanism of immune evasion developed by the human pathogenic Borrelia species to overcome innate immunity. These results will aid in the understanding of Lyme disease pathogenesis and pave the way for the development of new strategies to prevent Lyme disease.
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Affiliation(s)
- Kalvis Brangulis
- Latvian Biomedical Research and Study Centre, Ratsupites 1 k-1, LV-1067, Riga, Latvia. .,Riga Stradins University, Department of Human Physiology and Biochemistry, Dzirciema 16, LV-1007, Riga, Latvia.
| | - Inara Akopjana
- Latvian Biomedical Research and Study Centre, Ratsupites 1 k-1, LV-1067, Riga, Latvia
| | - Ivars Petrovskis
- Latvian Biomedical Research and Study Centre, Ratsupites 1 k-1, LV-1067, Riga, Latvia
| | - Andris Kazaks
- Latvian Biomedical Research and Study Centre, Ratsupites 1 k-1, LV-1067, Riga, Latvia
| | - Peter Kraiczy
- Institute of Medical Microbiology and Infection Control, University Hospital Frankfurt, Paul-Ehrlich-Str. 40, D-60596, Frankfurt am Main, Germany
| | - Kaspars Tars
- Latvian Biomedical Research and Study Centre, Ratsupites 1 k-1, LV-1067, Riga, Latvia.,University of Latvia, Faculty of Biology, Jelgavas 1, LV-1004, Riga, Latvia
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19
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Fernández FJ, Gómez S, Vega MC. Pathogens' toolbox to manipulate human complement. Semin Cell Dev Biol 2017; 85:98-109. [PMID: 29221973 DOI: 10.1016/j.semcdb.2017.12.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/30/2017] [Accepted: 12/03/2017] [Indexed: 12/15/2022]
Abstract
The surveillance and pathogen fighting functions of the complement system have evolved to protect mammals from life-threatening infections. In turn, pathogens have developed complex molecular mechanisms to subvert, divert and evade the effector functions of the complement. The study of complement immunoevasion by pathogens sheds light on their infection drivers, knowledge that is essential to implement therapies. At the same time, complement evasion also acts as a discovery ground that reveals important aspects of how complement works under physiological conditions. In recent years, complex interrelationships between infection insults and the onset of autoimmune and complement dysregulation diseases have led to propose that encounters with pathogens can act as triggering factors for disease. The correct management of these diseases involves the recognition of their triggering factors and the development and administration of complement-associated molecular therapies. Even more recently, unsuspected proteins from pathogens have been shown to possess moonlighting functions as virulence factors, raising the possibility that behind the first line of virulence factors there be many more pathogen proteins playing secondary, helping and supporting roles for the pathogen to successfully establish infections. In an era where antibiotics have a progressively reduced effect on the management and control of infectious diseases worldwide, knowledge on the mechanisms of pathogenic invasion and evasion look more necessary and pressing than ever.
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Affiliation(s)
| | - Sara Gómez
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain.
| | - M Cristina Vega
- Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain.
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20
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Crystal structure of a tripartite complex between C3dg, C-terminal domains of factor H and OspE of Borrelia burgdorferi. PLoS One 2017; 12:e0188127. [PMID: 29190743 PMCID: PMC5708776 DOI: 10.1371/journal.pone.0188127] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 11/01/2017] [Indexed: 11/19/2022] Open
Abstract
Complement is an important part of innate immunity. The alternative pathway of complement is activated when the main opsonin, C3b coats non-protected surfaces leading to opsonisation, phagocytosis and cell lysis. The alternative pathway is tightly controlled to prevent autoactivation towards host cells. The main regulator of the alternative pathway is factor H (FH), a soluble glycoprotein that terminates complement activation in multiple ways. FH recognizes host cell surfaces via domains 19-20 (FH19-20). All microbes including Borrelia burgdorferi, the causative agent of Lyme borreliosis, must evade complement activation to allow the infectious agent to survive in its host. One major mechanism that Borrelia uses is to recruit FH from host. Several outer surface proteins (Osp) have been described to bind FH via the C-terminus, and OspE is one of them. Here we report the structure of the tripartite complex formed by OspE, FH19-20 and C3dg at 3.18 Å, showing that OspE and C3dg can bind simultaneously to FH19-20. This verifies that FH19-20 interacts via the "common microbial binding site" on domain 20 with OspE and simultaneously and independently via domain 19 with C3dg. The spatial organization of the tripartite complex explains how OspE on the bacterial surface binds FH19-20, leaving FH fully available to protect the bacteria against complement. Additionally, formation of tripartite complex between FH, microbial protein and C3dg might enable enhanced protection, particularly on those regions on the bacteria where previous complement activation led to deposition of C3d. This might be especially important for slow-growing bacteria that cause chronic disease like Borrelia burgdorferi.
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21
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Blaum BS. The lectin self of complement factor H. Curr Opin Struct Biol 2017; 44:111-118. [DOI: 10.1016/j.sbi.2017.01.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 01/08/2017] [Accepted: 01/12/2017] [Indexed: 01/15/2023]
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Hiding in plain sight: immune evasion by the staphylococcal protein SdrE. Biochem J 2017; 474:1803-1806. [PMID: 28490660 DOI: 10.1042/bcj20170132] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 04/12/2017] [Accepted: 04/18/2017] [Indexed: 11/17/2022]
Abstract
The human immune system is responsible for identification and destruction of invader cells, such as the bacterial pathogen Staphylococcus aureus In response, S. aureus brings to the fight a large number of virulence factors, including several that allow it to evade the host immune response. The staphylococcal surface protein SdrE was recently reported to bind to complement Factor H, an important regulator of complement activation. Factor H attaches to the surface of host cells to inhibit complement activation and amplification, preventing the destruction of the host cell. SdrE binding to Factor H allows S. aureus to mimic a host cell and reduces bacterial killing by granulocytes. In a new study published in Biochemical Journal, Zhang et al. describe crystal structures of SdrE and its complex with the C-terminal portion of Factor H. The structure of SdrE and its interaction with the Factor H peptide closely resemble a family of surface proteins that recognize extracellular matrix components such as fibrinogen. However, unbound SdrE forms a novel 'Closed' conformation with an occluded peptide-binding groove. These structures reveal a fascinating mechanism for immune evasion and provide a potential avenue for the development of novel antimicrobial agents to target SdrE.
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Zhang Y, Wu M, Hang T, Wang C, Yang Y, Pan W, Zang J, Zhang M, Zhang X. Staphylococcus aureus SdrE captures complement factor H's C-terminus via a novel 'close, dock, lock and latch' mechanism for complement evasion. Biochem J 2017; 474:1619-1631. [PMID: 28258151 PMCID: PMC5415847 DOI: 10.1042/bcj20170085] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 03/02/2017] [Accepted: 03/03/2017] [Indexed: 12/30/2022]
Abstract
Complement factor H (CFH) is a soluble complement regulatory protein essential for the down-regulation of the alternative pathway on interaction with specific markers on the host cell surface. It recognizes the complement component 3b (C3b) and 3d (C3d) fragments in addition to self cell markers (i.e. glycosaminoglycans, sialic acid) to distinguish host cells that deserve protection from pathogens that should be eliminated. The Staphylococcus aureus surface protein serine-aspartate repeat protein E (SdrE) was previously reported to bind human CFH as an immune-evasion tactic. However, the molecular mechanism underlying SdrE-CFH-mediated immune evasion remains unknown. In the present study, we identified a novel region at CFH's C-terminus (CFH1206-1226), which binds SdrE N2 and N3 domains (SdrEN2N3) with high affinity, and determined the crystal structures of apo-SdrEN2N3 and the SdrEN2N3-CFH1206-1226 complex. Comparison of the structure of the CFH-SdrE complex with other CFH structures reveals that CFH's C-terminal tail flips from the main body to insert into the ligand-binding groove of SdrE. In addition, SdrEN2N3 adopts a 'close' state in the absence of CFH, which undergoes a large conformational change on CFH binding, suggesting a novel 'close, dock, lock and latch' (CDLL) mechanism for SdrE to recognize its ligand. Our findings imply that SdrE functions as a 'clamp' to capture CFH's C-terminal tail via a unique CDLL mechanism and sequesters CFH on the surface of S. aureus for complement evasion.
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Affiliation(s)
- Yingjie Zhang
- School of Life Science, Anhui University, 111 Jiulong Road, Hefei 230601, China
| | - Minhao Wu
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Center for Excellence in Biomacromolecules, Collaborative Innovation Center of Chemistry for Life Sciences, and School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Key Laboratory of Structural Biology, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Tianrong Hang
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Center for Excellence in Biomacromolecules, Collaborative Innovation Center of Chemistry for Life Sciences, and School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Key Laboratory of Structural Biology, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Chengliang Wang
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Center for Excellence in Biomacromolecules, Collaborative Innovation Center of Chemistry for Life Sciences, and School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Key Laboratory of Structural Biology, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Ye Yang
- School of Life Science, Anhui University, 111 Jiulong Road, Hefei 230601, China
| | - Weimin Pan
- School of Life Science, Anhui University, 111 Jiulong Road, Hefei 230601, China
| | - Jianye Zang
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Center for Excellence in Biomacromolecules, Collaborative Innovation Center of Chemistry for Life Sciences, and School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Key Laboratory of Structural Biology, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Min Zhang
- School of Life Science, Anhui University, 111 Jiulong Road, Hefei 230601, China
| | - Xuan Zhang
- Hefei National Laboratory for Physical Sciences at Microscale, CAS Center for Excellence in Biomacromolecules, Collaborative Innovation Center of Chemistry for Life Sciences, and School of Life Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Key Laboratory of Structural Biology, Chinese Academy of Sciences, 96 Jinzhai Road, Hefei, Anhui 230026, China
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Conde JN, Silva EM, Barbosa AS, Mohana-Borges R. The Complement System in Flavivirus Infections. Front Microbiol 2017; 8:213. [PMID: 28261172 PMCID: PMC5306369 DOI: 10.3389/fmicb.2017.00213] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 01/30/2017] [Indexed: 01/29/2023] Open
Abstract
The incidence of flavivirus infections has increased dramatically in recent decades in tropical and sub-tropical climates worldwide, affecting hundreds of millions of people each year. The Flaviviridae family includes dengue, West Nile, Zika, Japanese encephalitis, and yellow fever viruses that are typically transmitted by mosquitoes or ticks, and cause a wide range of symptoms, such as fever, shock, meningitis, paralysis, birth defects, and death. The flavivirus genome is composed of a single positive-sense RNA molecule encoding a single viral polyprotein. This polyprotein is further processed by viral and host proteases into three structural proteins (C, prM/M, E) and seven non-structural proteins (NS1, NS2A, NS2B, NS3, NS4A, NS4B, NS5) that are involved in viral replication and pathogenicity. The complement system has been described to play an important role in flavivirus infection either by protecting the host and/or by influencing disease pathogenesis. In this mini-review, we will explore the role of complement system inhibition and/or activation against infection by the Flavivirus genus, with an emphasis on dengue and West Nile viruses.
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Affiliation(s)
- Jonas N Conde
- Laboratório de Genômica Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil
| | - Emiliana M Silva
- Laboratório de Genômica Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil
| | - Angela S Barbosa
- Laboratório de Bacteriologia, Instituto Butantan São Paulo, Brazil
| | - Ronaldo Mohana-Borges
- Laboratório de Genômica Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil
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25
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Hovingh ES, van den Broek B, Jongerius I. Hijacking Complement Regulatory Proteins for Bacterial Immune Evasion. Front Microbiol 2016; 7:2004. [PMID: 28066340 PMCID: PMC5167704 DOI: 10.3389/fmicb.2016.02004] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 11/30/2016] [Indexed: 12/11/2022] Open
Abstract
The human complement system plays an important role in the defense against invading pathogens, inflammation and homeostasis. Invading microbes, such as bacteria, directly activate the complement system resulting in the formation of chemoattractants and in effective labeling of the bacteria for phagocytosis. In addition, formation of the membrane attack complex is responsible for direct killing of Gram-negative bacteria. In turn, bacteria have evolved several ways to evade complement activation on their surface in order to be able to colonize and invade the human host. One important mechanism of bacterial escape is attraction of complement regulatory proteins to the microbial surface. These molecules are present in the human body for tight regulation of the complement system to prevent damage to host self-surfaces. Therefore, recruitment of complement regulatory proteins to the bacterial surface results in decreased complement activation on the microbial surface which favors bacterial survival. This review will discuss recent advances in understanding the binding of complement regulatory proteins to the bacterial surface at the molecular level. This includes, new insights that have become available concerning specific conserved motives on complement regulatory proteins that are favorable for microbial binding. Finally, complement evasion molecules are of high importance for vaccine development due to their dominant role in bacterial survival, high immunogenicity and homology as well as their presence on the bacterial surface. Here, the use of complement evasion molecules for vaccine development will be discussed.
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Affiliation(s)
- Elise S. Hovingh
- Department of Medical Microbiology, University Medical Center UtrechtUtrecht, Netherlands
- Centre for Infectious Disease Control, National Institute for Public Health and the EnvironmentBilthoven, Netherlands
| | - Bryan van den Broek
- Department of Medical Microbiology, University Medical Center UtrechtUtrecht, Netherlands
| | - Ilse Jongerius
- Department of Medical Microbiology, University Medical Center UtrechtUtrecht, Netherlands
- Centre for Infectious Disease Control, National Institute for Public Health and the EnvironmentBilthoven, Netherlands
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26
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Travelling between Two Worlds: Complement as a Gatekeeper for an Expanded Host Range of Lyme Disease Spirochetes. Vet Sci 2016; 3:vetsci3020012. [PMID: 29056721 PMCID: PMC5644625 DOI: 10.3390/vetsci3020012] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 06/03/2016] [Accepted: 06/06/2016] [Indexed: 01/21/2023] Open
Abstract
Evading innate immunity is a prerequisite for pathogenic microorganisms in order to survive in their respective hosts. Concerning Lyme disease spirochetes belonging to the Borrelia (B.) burgdorferi sensu lato group, a broad range of diverse vertebrates serve as reservoir or even as incidental hosts, including humans. The capability to infect multiple hosts implies that spirochetes have developed sophisticated means to counter the destructive effects of complement of humans and various animals. While the means by which spirochetes overcome the hosts immune defense are far from being completely understood, there is a growing body of evidence suggesting that binding of the key regulator of the alternative pathway, Factor H, plays a pivotal role for immune evasion and that Factor H is an important determinant of host specificity. This review covers (i) the contribution of complement in host-specificity and transmissibility of Lyme disease spirochetes; (ii) the involvement of borrelial-derived determinants to host specificity; (iii) the interplay of human and animal Factor H with complement-acquiring surface proteins of diverse borrelial species; and (iv) the potential role of additional animal complement proteins in the immune evasion of spirochetes.
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27
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Ram S, Shaughnessy J, DeOliveira RB, Lewis LA, Gulati S, Rice PA. Utilizing complement evasion strategies to design complement-based antibacterial immunotherapeutics: Lessons from the pathogenic Neisseriae. Immunobiology 2016; 221:1110-23. [PMID: 27297292 DOI: 10.1016/j.imbio.2016.05.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 05/27/2016] [Indexed: 12/30/2022]
Abstract
Novel therapies are urgently needed to combat the global threat of multidrug-resistant pathogens. Complement forms an important arm of innate defenses against infections. In physiological conditions, complement activation is tightly controlled by soluble and membrane-associated complement inhibitors, but must be selectively activated on invading pathogens to facilitate microbial clearance. Many pathogens, including Neisseria gonorrhoeae and N. meningitidis, express glycans, including N-acetylneuraminic acid (Neu5Ac), that mimic host structures to evade host immunity. Neu5Ac is a negatively charged 9-cabon sugar that inhibits complement, in part by enhancing binding of the complement inhibitor factor H (FH) through C-terminal domains (19 and 20) on FH. Other microbes also bind FH, in most instances through FH domains 6 and 7 or 18-20. Here we describe two strategies to target complement activation on Neisseriae. First, microbial binding domains of FH were fused to IgG Fc to create FH18-20/Fc (binds gonococci) and FH6,7/Fc (binds meningococci). A point mutation in FH domain 19 eliminated hemolysis caused by unmodified FH18-20, but retained binding to gonococci. FH18-20/Fc and FH6,7/Fc mediated complement-dependent killing in vitro and showed efficacy in animal models of gonorrhea and meningococcal bacteremia, respectively. The second strategy utilized CMP-nonulosonate (CMP-NulO) analogs of sialic acid that were incorporated into LOS and prevented complement inhibition by physiologic CMP-Neu5Ac and resulted in attenuated gonococcal infection in mice. While studies to establish the safety of these agents are needed, enhancing complement activation on microbes may represent a promising strategy to treat antimicrobial resistant organisms.
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Affiliation(s)
- Sanjay Ram
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
| | - Jutamas Shaughnessy
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Rosane B DeOliveira
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Lisa A Lewis
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Sunita Gulati
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Peter A Rice
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605, USA
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28
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Cagliani R, Forni D, Filippi G, Mozzi A, De Gioia L, Pontremoli C, Pozzoli U, Bresolin N, Clerici M, Sironi M. The mammalian complement system as an epitome of host-pathogen genetic conflicts. Mol Ecol 2016; 25:1324-39. [PMID: 26836579 DOI: 10.1111/mec.13558] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/29/2015] [Accepted: 01/27/2016] [Indexed: 12/11/2022]
Abstract
The complement system is an innate immunity effector mechanism; its action is antagonized by a wide array of pathogens and complement evasion determines the virulence of several infections. We investigated the evolutionary history of the complement system and of bacterial-encoded complement-interacting proteins. Complement components targeted by several pathogens evolved under strong selective pressure in primates, with selection acting on residues at the contact interface with microbial/viral proteins. Positively selected sites in CFH and C4BPA account for the human specificity of gonococcal infection. Bacterial interactors, evolved adaptively as well, with selected sites located at interaction surfaces with primate complement proteins. These results epitomize the expectation under a genetic conflict scenario whereby the host's and the pathogen's genes evolve within binding avoidance-binding seeking dynamics. In silico mutagenesis and protein-protein docking analyses supported this by showing that positively selected sites, both in the host's and in the pathogen's interacting partner, modulate binding.
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Affiliation(s)
- Rachele Cagliani
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Diego Forni
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Giulia Filippi
- Department of Biotechnology and Biosciences, University of Milan-Bicocca, 20126, Milan, Italy
| | - Alessandra Mozzi
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Luca De Gioia
- Department of Biotechnology and Biosciences, University of Milan-Bicocca, 20126, Milan, Italy
| | - Chiara Pontremoli
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Uberto Pozzoli
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
| | - Nereo Bresolin
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy.,Dino Ferrari Centre, Department of Physiopathology and Transplantation, University of Milan, Fondazione Ca' Granda IRCCS Ospedale Maggiore Policlinico, 20122, Milan, Italy
| | - Mario Clerici
- Department of Physiopathology and Transplantation, University of Milan, 20090, Milan, Italy.,Don C. Gnocchi Foundation ONLUS, IRCCS, 20148, Milan, Italy
| | - Manuela Sironi
- Bioinformatics, Scientific Institute IRCCS E. MEDEA, 23842, Bosisio Parini, Italy
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29
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Anti-complement activity of the Ixodes scapularis salivary protein Salp20. Mol Immunol 2015; 69:62-9. [PMID: 26675068 DOI: 10.1016/j.molimm.2015.11.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 11/17/2015] [Accepted: 11/18/2015] [Indexed: 02/06/2023]
Abstract
Complement, a major component of innate immunity, presents a rapid and robust defense of the intravascular space. While regulatory proteins protect host cells from complement attack, when these measures fail, unrestrained complement activation may trigger self-tissue injury, leading to pathologic conditions. Of the three complement activation pathways, the alternative pathway (AP) in particular has been implicated in numerous disease and injury states. Consequently, the AP components represent attractive targets for therapeutic intervention. The common hard-bodied ticks from the family Ixodidae derive nourishment from the blood of their mammalian hosts. During its blood meal the tick is exposed to host immune effectors, including the complement system. In defense, the tick produces salivary proteins that can inhibit host immune functions. The Salp20 salivary protein of Ixodes scapularis inhibits the host AP pathway by binding properdin and dissociating C3bBbP, the active C3 convertase. In these studies we examined Salp20 activity in various complement-mediated pathologies. Our results indicate that Salp20 can inhibit AP-dependent pathogenesis in the mouse. Its efficacy may be part in due to synergic effects it provides with the endogenous AP regulator, factor H. While Salp20 itself would be expected to be highly immunogenic and therefore inappropriate for therapeutic use, its emergence speaks for the potential development of a non-immunogenic Salp20 mimic that replicates its anti-properdin activity.
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30
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Human Coinfection with Borrelia burgdorferi and Babesia microti in the United States. J Parasitol Res 2015; 2015:587131. [PMID: 26697208 PMCID: PMC4677215 DOI: 10.1155/2015/587131] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 11/08/2015] [Indexed: 11/18/2022] Open
Abstract
Borrelia burgdorferi, the causative agent of Lyme disease, and Babesia microti, a causative agent of babesiosis, are increasingly implicated in the growing tick-borne disease burden in the northeastern United States. These pathogens are transmitted via the bite of an infected tick vector, Ixodes scapularis, which is capable of harboring and inoculating a host with multiple pathogens simultaneously. Clinical presentation of the diseases is heterogeneous and ranges from mild flu-like symptoms to near-fatal cardiac arrhythmias. While the reason for the variability is not known, the possibility exists that concomitant infection with both B. burgdorferi and B. microti may synergistically increase disease severity. In an effort to clarify the current state of understanding regarding coinfection with B. burgdorferi and B. microti, in this review, we discuss the geographical distribution and pathogenesis of Lyme disease and babesiosis in the United States, the immunological response of humans to B. burgdorferi or B. microti infection, the existing knowledge regarding coinfection disease pathology, and critical factors that have led to ambiguity in the literature regarding coinfection, in order to eliminate confusion in future experimental design and investigation.
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31
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Toledo A, Pérez A, Coleman JL, Benach JL. The lipid raft proteome of Borrelia burgdorferi. Proteomics 2015; 15:3662-75. [PMID: 26256460 DOI: 10.1002/pmic.201500093] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Revised: 07/09/2015] [Accepted: 08/03/2015] [Indexed: 12/15/2022]
Abstract
Eukaryotic lipid rafts are membrane microdomains that have significant amounts of cholesterol and a selective set of proteins that have been associated with multiple biological functions. The Lyme disease agent, Borrelia burgdorferi, is one of an increasing number of bacterial pathogens that incorporates cholesterol onto its membrane, and form cholesterol glycolipid domains that possess all the hallmarks of eukaryotic lipid rafts. In this study, we isolated lipid rafts from cultured B. burgdorferi as a detergent resistant membrane (DRM) fraction on density gradients, and characterized those molecules that partitioned exclusively or are highly enriched in these domains. Cholesterol glycolipids, the previously known raft-associated lipoproteins OspA and OpsB, and cholera toxin partitioned into the lipid rafts fraction indicating compatibility with components of the DRM. The proteome of lipid rafts was analyzed by a combination of LC-MS/MS or MudPIT. Identified proteins were analyzed in silico for parameters that included localization, isoelectric point, molecular mass and biological function. The proteome provided a consistent pattern of lipoproteins, proteases and their substrates, sensing molecules and prokaryotic homologs of eukaryotic lipid rafts. This study provides the first analysis of a prokaryotic lipid raft and has relevance for the biology of Borrelia, other pathogenic bacteria, as well as for the evolution of these structures. All MS data have been deposited in the ProteomeXchange with identifier PXD002365 (http://proteomecentral.proteomexchange.org/dataset/PXD002365).
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Affiliation(s)
- Alvaro Toledo
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Alberto Pérez
- Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, NY, USA
| | - James L Coleman
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA.,New York State Department of Health, Stony Brook University, Stony Brook, NY, USA
| | - Jorge L Benach
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
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32
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Morris G, Berk M, Walder K, Maes M. The Putative Role of Viruses, Bacteria, and Chronic Fungal Biotoxin Exposure in the Genesis of Intractable Fatigue Accompanied by Cognitive and Physical Disability. Mol Neurobiol 2015; 53:2550-71. [PMID: 26081141 DOI: 10.1007/s12035-015-9262-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 05/28/2015] [Indexed: 01/08/2023]
Abstract
Patients who present with severe intractable apparently idiopathic fatigue accompanied by profound physical and or cognitive disability present a significant therapeutic challenge. The effect of psychological counseling is limited, with significant but very slight improvements in psychometric measures of fatigue and disability but no improvement on scientific measures of physical impairment compared to controls. Similarly, exercise regimes either produce significant, but practically unimportant, benefit or provoke symptom exacerbation. Many such patients are afforded the exclusionary, non-specific diagnosis of chronic fatigue syndrome if rudimentary testing fails to discover the cause of their symptoms. More sophisticated investigations often reveal the presence of a range of pathogens capable of establishing life-long infections with sophisticated immune evasion strategies, including Parvoviruses, HHV6, variants of Epstein-Barr, Cytomegalovirus, Mycoplasma, and Borrelia burgdorferi. Other patients have a history of chronic fungal or other biotoxin exposure. Herein, we explain the epigenetic factors that may render such individuals susceptible to the chronic pathology induced by such agents, how such agents induce pathology, and, indeed, how such pathology can persist and even amplify even when infections have cleared or when biotoxin exposure has ceased. The presence of active, reactivated, or even latent Herpes virus could be a potential source of intractable fatigue accompanied by profound physical and or cognitive disability in some patients, and the same may be true of persistent Parvovirus B12 and mycoplasma infection. A history of chronic mold exposure is a feasible explanation for such symptoms, as is the presence of B. burgdorferi. The complex tropism, life cycles, genetic variability, and low titer of many of these pathogens makes their detection in blood a challenge. Examination of lymphoid tissue or CSF in such circumstances may be warranted.
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Affiliation(s)
- Gerwyn Morris
- Tir Na Nog, Bryn Road seaside 87, Llanelli, SA15 2LW, Wales, UK
| | - Michael Berk
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia.,Orygen, The National Centre of Excellence in Youth Mental Health, Department of Psychiatry and The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, Australia
| | - Ken Walder
- Centre for Molecular and Medical Research, School of Medicine, Deakin University, Geelong, Australia
| | - Michael Maes
- IMPACT Strategic Research Centre, School of Medicine, Deakin University, Geelong, Australia. .,Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
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33
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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: 628] [Impact Index Per Article: 69.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 05/09/2015] [Indexed: 12/14/2022] Open
Abstract
The complement system has been considered for a long time as a simple lytic cascade, aimed to kill bacteria infecting the host organism. Nowadays, this vision has changed and it is well accepted that complement is a complex innate immune surveillance system, playing a key role in host homeostasis, inflammation, and in the defense against pathogens. This review discusses recent advances in the understanding of the role of complement in physiology and pathology. It starts with a description of complement contribution to the normal physiology (homeostasis) of a healthy organism, including the silent clearance of apoptotic cells and maintenance of cell survival. In pathology, complement can be a friend or a foe. It acts as a friend in the defense against pathogens, by inducing opsonization and a direct killing by C5b–9 membrane attack complex and by triggering inflammatory responses with the anaphylatoxins C3a and C5a. Opsonization plays also a major role in the mounting of an adaptive immune response, involving antigen presenting cells, T-, and B-lymphocytes. Nevertheless, it can be also an enemy, when pathogens hijack complement regulators to protect themselves from the immune system. Inadequate complement activation becomes a disease cause, as in atypical hemolytic uremic syndrome, C3 glomerulopathies, and systemic lupus erythematosus. Age-related macular degeneration and cancer will be described as examples showing that complement contributes to a large variety of conditions, far exceeding the classical examples of diseases associated with complement deficiencies. Finally, we discuss complement as a therapeutic target.
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Affiliation(s)
- Nicolas S Merle
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France
| | - Remi Noe
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France ; Ecole Pratique des Hautes Études (EPHE) , Paris , France
| | - Lise Halbwachs-Mecarelli
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France
| | - Veronique Fremeaux-Bacchi
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France ; Service d'Immunologie Biologique, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou , Paris , France
| | - Lubka T Roumenina
- UMRS 1138, Centre de Recherche des Cordeliers, INSERM , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Paris Cité, Université Paris Descartes , Paris , France ; UMRS 1138, Centre de Recherche des Cordeliers, Sorbonne Universités, UPMC Université Paris 06 , Paris , France
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Cyclic di-GMP modulates gene expression in Lyme disease spirochetes at the tick-mammal interface to promote spirochete survival during the blood meal and tick-to-mammal transmission. Infect Immun 2015; 83:3043-60. [PMID: 25987708 DOI: 10.1128/iai.00315-15] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 05/11/2015] [Indexed: 01/02/2023] Open
Abstract
Borrelia burgdorferi, the Lyme disease spirochete, couples environmental sensing and gene regulation primarily via the Hk1/Rrp1 two-component system (TCS) and Rrp2/RpoN/RpoS pathways. Beginning with acquisition, we reevaluated the contribution of these pathways to spirochete survival and gene regulation throughout the enzootic cycle. Live imaging of B. burgdorferi caught in the act of being acquired revealed that the absence of RpoS and the consequent derepression of tick-phase genes impart a Stay signal required for midgut colonization. In addition to the behavioral changes brought on by the RpoS-off state, acquisition requires activation of cyclic di-GMP (c-di-GMP) synthesis by the Hk1/Rrp1 TCS; B. burgdorferi lacking either component is destroyed during the blood meal. Prior studies attributed this dramatic phenotype to a metabolic lesion stemming from reduced glycerol uptake and utilization. In a head-to-head comparison, however, the B. burgdorferi Δglp mutant had a markedly greater capacity to survive tick feeding than B. burgdorferi Δhk1 or Δrrp1 mutants, establishing unequivocally that glycerol metabolism is only one component of the protection afforded by c-di-GMP. Data presented herein suggest that the protective response mediated by c-di-GMP is multifactorial, involving chemotactic responses, utilization of alternate substrates for energy generation and intermediary metabolism, and remodeling of the cell envelope as a means of defending spirochetes against threats engendered during the blood meal. Expression profiling of c-di-GMP-regulated genes through the enzootic cycle supports our contention that the Hk1/Rrp1 TCS functions primarily, if not exclusively, in ticks. These data also raise the possibility that c-di-GMP enhances the expression of a subset of RpoS-dependent genes during nymphal transmission.
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Akey DL, Brown WC, Jose J, Kuhn RJ, Smith JL. Structure-guided insights on the role of NS1 in flavivirus infection. Bioessays 2015; 37:489-94. [PMID: 25761098 DOI: 10.1002/bies.201400182] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/22/2014] [Accepted: 01/28/2015] [Indexed: 12/20/2022]
Abstract
We highlight the various domains of the flavivirus virulence factor NS1 and speculate on potential implications of the NS1 3D structure in understanding its role in flavivirus pathogenesis. Flavivirus non-structural protein 1 (NS1) is a virulence factor with dual functions in genome replication and immune evasion. Crystal structures of NS1, combined with reconstructions from electron microscopy (EM), provide insight into the architecture of dimeric NS1 on cell membranes and the assembly of a secreted hexameric NS1-lipid complex found in patient sera. Three structural domains of NS1 likely have distinct roles in membrane association, replication complex assembly, and immune system avoidance. A conserved hydrophobic inner face is sequestered either on the membrane or in the interior of the secreted hexamer and contains regions implicated in viral replication. The exposed variable outer face is presented to cellular and secreted components of the immune system in infected patients and contains candidate regions for immune system modulation. We anticipate that knowledge of the distinct NS1 domains and assembly will lead to advances in elucidating virus-host interactions mediated through NS1 and in dissecting the role of NS1 in viral genome replication.
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Affiliation(s)
- David L Akey
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
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Bhattacharjee A, Reuter S, Trojnár E, Kolodziejczyk R, Seeberger H, Hyvärinen S, Uzonyi B, Szilágyi Á, Prohászka Z, Goldman A, Józsi M, Jokiranta TS. The major autoantibody epitope on factor H in atypical hemolytic uremic syndrome is structurally different from its homologous site in factor H-related protein 1, supporting a novel model for induction of autoimmunity in this disease. J Biol Chem 2015; 290:9500-10. [PMID: 25659429 PMCID: PMC4392255 DOI: 10.1074/jbc.m114.630871] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Indexed: 01/26/2023] Open
Abstract
Atypical hemolytic uremic syndrome (aHUS) is characterized by complement attack against host cells due to mutations in complement proteins or autoantibodies against complement factor H (CFH). It is unknown why nearly all patients with autoimmune aHUS lack CFHR1 (CFH-related protein-1). These patients have autoantibodies against CFH domains 19 and 20 (CFH19–20), which are nearly identical to CFHR1 domains 4 and 5 (CFHR14–5). Here, binding site mapping of autoantibodies from 17 patients using mutant CFH19–20 constructs revealed an autoantibody epitope cluster within a loop on domain 20, next to the two buried residues that are different in CFH19–20 and CFHR14–5. The crystal structure of CFHR14–5 revealed a difference in conformation of the autoantigenic loop in the C-terminal domains of CFH and CFHR1, explaining the variation in binding of autoantibodies from some aHUS patients to CFH19–20 and CFHR14–5. The autoantigenic loop on CFH seems to be generally flexible, as its conformation in previously published structures of CFH19–20 bound to the microbial protein OspE and a sialic acid glycan is somewhat altered. Cumulatively, our data suggest that association of CFHR1 deficiency with autoimmune aHUS could be due to the structural difference between CFHR1 and the autoantigenic CFH epitope, suggesting a novel explanation for CFHR1 deficiency in the pathogenesis of autoimmune aHUS.
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Affiliation(s)
- Arnab Bhattacharjee
- From the Department of Bacteriology and Immunology, Medicum, and Immunobiology Research Program Unit, University of Helsinki and Helsinki University Hospital, 00014 University of Helsinki, Finland, the Institute of Biotechnology and
| | - Stefanie Reuter
- the Junior Research Group for Cellular Immunobiology, Leibniz Institute for Natural Product, Research and Infection Biology-Hans Knöll Institute, 07745 Jena, Germany
| | - Eszter Trojnár
- the Research Laboratory, 3rd Department of Internal Medicine, Semmelweis University, 1125 Budapest, Hungary, and
| | - Robert Kolodziejczyk
- the Institute of Biotechnology and Division of Biochemistry and Biotechnology, Department of Biosciences, University of Helsinki, 00014 University of Helsinki, Finland
| | - Harald Seeberger
- the Junior Research Group for Cellular Immunobiology, Leibniz Institute for Natural Product, Research and Infection Biology-Hans Knöll Institute, 07745 Jena, Germany
| | - Satu Hyvärinen
- From the Department of Bacteriology and Immunology, Medicum, and Immunobiology Research Program Unit, University of Helsinki and Helsinki University Hospital, 00014 University of Helsinki, Finland
| | | | - Ágnes Szilágyi
- the Research Laboratory, 3rd Department of Internal Medicine, Semmelweis University, 1125 Budapest, Hungary, and
| | - Zoltán Prohászka
- the Research Laboratory, 3rd Department of Internal Medicine, Semmelweis University, 1125 Budapest, Hungary, and
| | - Adrian Goldman
- the Institute of Biotechnology and Division of Biochemistry and Biotechnology, Department of Biosciences, University of Helsinki, 00014 University of Helsinki, Finland
| | - Mihály Józsi
- the Junior Research Group for Cellular Immunobiology, Leibniz Institute for Natural Product, Research and Infection Biology-Hans Knöll Institute, 07745 Jena, Germany, MTA-ELTE "Lendület" Complement Research Group, Department of Immunology, Eötvös Loránd University, 1117 Budapest, Hungary
| | - T Sakari Jokiranta
- From the Department of Bacteriology and Immunology, Medicum, and Immunobiology Research Program Unit, University of Helsinki and Helsinki University Hospital, 00014 University of Helsinki, Finland
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Brangulis K, Petrovskis I, Kazaks A, Akopjana I, Tars K. Crystal structures of the Erp protein family members ErpP and ErpC from Borrelia burgdorferi reveal the reason for different affinities for complement regulator factor H. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2015; 1854:349-55. [PMID: 25582082 DOI: 10.1016/j.bbapap.2014.12.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 12/13/2014] [Accepted: 12/23/2014] [Indexed: 11/17/2022]
Abstract
Borrelia burgdorferi is the causative agent of Lyme disease, which can be acquired after the bite of an infected Ixodes tick. As a strategy to resist the innate immunity and to successfully spread and proliferate, B. burgdorferi expresses a set of outer membrane proteins that are capable of binding complement regulator factor H (CFH), factor H-like protein 1 (CFHL-1) and factor H-related proteins (CFHR) to avoid complement-mediated killing. B. burgdorferi B31 contains three proteins that belong to the Erp (OspE/F-related) protein family and are capable of binding CFH and some CFHRs, namely ErpA, ErpC and ErpP. We have determined the crystal structure of ErpP at 2.53Å resolution and the crystal structure of ErpC at 2.15Å resolution. Recently, the crystal structure of the Erp family member OspE from B. burgdorferi N40 was determined in complex with CFH domains 19-20, revealing the residues involved in the complex formation. Despite the high sequence conservation between ErpA, ErpC, ErpP and the homologous protein OspE (78-80%), the affinity for CFH and CFHRs differs markedly among the Erp family members, suggesting that ErpC may bind only CFHRs but not CFH. A comparison of the binding site in OspE with those of ErpC and ErpP revealed that the extended loop region, which is only observed in the potential binding site of ErpC, plays an important role by preventing the binding of CFH. These results can explain the inability of ErpC to bind CFH, whereas ErpP and ErpA still possess the ability to bind CFH.
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Affiliation(s)
- Kalvis Brangulis
- Latvian Institute of Organic Synthesis, Aizkraukles 21, LV-1006 Riga, Latvia; Latvian Biomedical Research and Study Centre, Ratsupites 1, LV-1067 Riga, Latvia; Riga Stradins University, Dzirciema 16, LV-1007 Riga, Latvia.
| | - Ivars Petrovskis
- Latvian Biomedical Research and Study Centre, Ratsupites 1, LV-1067 Riga, Latvia
| | - Andris Kazaks
- Latvian Biomedical Research and Study Centre, Ratsupites 1, LV-1067 Riga, Latvia
| | - Inara Akopjana
- Latvian Biomedical Research and Study Centre, Ratsupites 1, LV-1067 Riga, Latvia
| | - Kaspars Tars
- Latvian Biomedical Research and Study Centre, Ratsupites 1, LV-1067 Riga, Latvia; University of Latvia, Kronvalda bulv. 4, LV-1586, Riga, Latvia
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Blaum BS, Hannan JP, Herbert AP, Kavanagh D, Uhrín D, Stehle T. Structural basis for sialic acid-mediated self-recognition by complement factor H. Nat Chem Biol 2014; 11:77-82. [PMID: 25402769 DOI: 10.1038/nchembio.1696] [Citation(s) in RCA: 204] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 10/02/2014] [Indexed: 12/25/2022]
Abstract
The serum protein complement factor H (FH) ensures downregulation of the complement alternative pathway, a branch of innate immunity, upon interaction with specific glycans on host cell surfaces. Using ligand-based NMR, we screened a comprehensive set of sialylated glycans for binding to FH and solved the crystal structure of a ternary complex formed by the two C-terminal domains of FH, a sialylated trisaccharide and the complement C3b thioester-containing domain. Key residues in the sialic acid binding site are conserved from mice to men, and residues linked to atypical hemolytic uremic syndrome cluster within this binding site, suggesting a possible role for sialic acid as a host marker also in other mammals and a critical role in human renal complement homeostasis. Unexpectedly, the FH sialic acid binding site is structurally homologous to the binding sites of two evolutionarily unrelated proteins. The crystal structure also advances our understanding of bacterial immune evasion strategies.
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Affiliation(s)
- Bärbel S Blaum
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Jonathan P Hannan
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, USA
| | | | - David Kavanagh
- Institute of Genetic Medicine, International Centre for Life, Newcastle upon Tyne, UK
| | - Dušan Uhrín
- The School of Chemistry, University of Edinburgh, Scotland, UK
| | - Thilo Stehle
- 1] Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany. [2] Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
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Borgermans L, Goderis G, Vandevoorde J, Devroey D. Relevance of chronic lyme disease to family medicine as a complex multidimensional chronic disease construct: a systematic review. INTERNATIONAL JOURNAL OF FAMILY MEDICINE 2014; 2014:138016. [PMID: 25506429 PMCID: PMC4258916 DOI: 10.1155/2014/138016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 11/12/2014] [Indexed: 06/04/2023]
Abstract
Lyme disease has become a global public health problem and a prototype of an emerging infection. Both treatment-refractory infection and symptoms that are related to Borrelia burgdorferi infection remain subject to controversy. Because of the absence of solid evidence on prevalence, causes, diagnostic criteria, tools and treatment options, the role of autoimmunity to residual or persisting antigens, and the role of a toxin or other bacterial-associated products that are responsible for the symptoms and signs, chronic Lyme disease (CLD) remains a relatively poorly understood chronic disease construct. The role and performance of family medicine in the detection, integrative treatment, and follow-up of CLD are not well studied either. The purpose of this paper is to describe insights into the complexity of CLD as a multidimensional chronic disease construct and its relevance to family medicine by means of a systematic literature review.
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Affiliation(s)
- Liesbeth Borgermans
- Department of Family Medicine & Chronic Care, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Geert Goderis
- Department of General Practice and University Hospitals Leuven, Katholieke Universiteit Leuven (KUL), Kapucijnenvoer 33, 3000 Leuven, Belgium
| | - Jan Vandevoorde
- Department of Family Medicine & Chronic Care, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Dirk Devroey
- Department of Family Medicine & Chronic Care, Vrije Universiteit Brussel (VUB), Laarbeeklaan 103, 1090 Brussels, Belgium
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van Dissel D, Claessen D, van Wezel GP. Morphogenesis of Streptomyces in submerged cultures. ADVANCES IN APPLIED MICROBIOLOGY 2014; 89:1-45. [PMID: 25131399 DOI: 10.1016/b978-0-12-800259-9.00001-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Members of the genus Streptomyces are mycelial bacteria that undergo a complex multicellular life cycle and propagate via sporulation. Streptomycetes are important industrial microorganisms, as they produce a plethora of medically relevant natural products, including the majority of clinically important antibiotics, as well as a wide range of enzymes with industrial application. While development of Streptomyces in surface-grown cultures is well studied, relatively little is known of the parameters that determine morphogenesis in submerged cultures. Here, growth is characterized by the formation of mycelial networks and pellets. From the perspective of industrial fermentations, such mycelial growth is unattractive, as it is associated with slow growth, heterogeneous cultures, and high viscosity. Here, we review the current insights into the genetic and environmental factors that determine mycelial growth and morphology in liquid-grown cultures. The genetic factors include cell-matrix proteins and extracellular polymers, morphoproteins with specific roles in liquid-culture morphogenesis, with the SsgA-like proteins as well-studied examples, and programmed cell death. Environmental factors refer in particular to those dictated by process engineering, such as growth media and reactor set-up. These insights are then integrated to provide perspectives as to how this knowledge can be applied to improve streptomycetes for industrial applications.
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Affiliation(s)
- Dino van Dissel
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Leiden, The Netherlands
| | - Dennis Claessen
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Leiden, The Netherlands.
| | - Gilles P van Wezel
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Leiden, The Netherlands.
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Kelesidis T. The Cross-Talk between Spirochetal Lipoproteins and Immunity. Front Immunol 2014; 5:310. [PMID: 25071771 PMCID: PMC4075078 DOI: 10.3389/fimmu.2014.00310] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 06/17/2014] [Indexed: 12/11/2022] Open
Abstract
Spirochetal diseases such as syphilis, Lyme disease, and leptospirosis are major threats to public health. However, the immunopathogenesis of these diseases has not been fully elucidated. Spirochetes interact with the host through various structural components such as lipopolysaccharides (LPS), surface lipoproteins, and glycolipids. Although spirochetal antigens such as LPS and glycolipids may contribute to the inflammatory response during spirochetal infections, spirochetes such as Treponema pallidum and Borrelia burgdorferi lack LPS. Lipoproteins are most abundant proteins that are expressed in all spirochetes and often determine how spirochetes interact with their environment. Lipoproteins are pro-inflammatory, may regulate responses from both innate and adaptive immunity and enable the spirochetes to adhere to the host or the tick midgut or to evade the immune system. However, most of the spirochetal lipoproteins have unknown function. Herein, the immunomodulatory effects of spirochetal lipoproteins are reviewed and are grouped into two main categories: effects related to immune evasion and effects related to immune activation. Understanding lipoprotein-induced immunomodulation will aid in elucidating innate immunopathogenesis processes and subsequent adaptive mechanisms potentially relevant to spirochetal disease vaccine development and to inflammatory events associated with spirochetal diseases.
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Affiliation(s)
- Theodoros Kelesidis
- Division of Infectious Diseases, Department of Medicine, David Geffen School of Medicine, University of California Los Angeles , Los Angeles, CA , USA
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Fleury C, Su YC, Hallström T, Sandblad L, Zipfel PF, Riesbeck K. Identification of a Haemophilus influenzae factor H-Binding lipoprotein involved in serum resistance. THE JOURNAL OF IMMUNOLOGY 2014; 192:5913-23. [PMID: 24835392 DOI: 10.4049/jimmunol.1303449] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Haemophilus influenzae is a Gram-negative human pathogen that resides in the upper respiratory tract. Encapsulated H. influenzae type b (Hib) and type f (Hif) are the most common serotypes associated with invasive disease. H. influenzae displays various strategies to circumvent the host innate immune response, including the bactericidal effect of the complement system. In this study, we identified an H. influenzae lipoprotein having the ability to bind factor H (FH), the major regulator of the alternative pathway of complement activation. This protein, named protein H (PH), was surface exposed and was found in all clinical Hib and Hif isolates tested. Deletion of the gene encoding for PH (lph) in Hib and Hif significantly reduced the interaction between bacteria and FH. When Hib and Hif PH variants were separately expressed in nontypeable (unencapsulated) H. influenzae, which did not bind FH, an increased FH affinity was observed. We recombinantly expressed the two PH variants in Escherichia coli, and despite sharing only 56% identical amino acids, both FH-binding Haemophilus proteins similarly interacted with the complement regulator FH short consensus repeats 7 and 18-20. Importantly, Hib and Hif resistance against the bactericidal effect of human serum was significantly reduced when bacterial mutants devoid of PH were tested. In conclusion, we have characterized a hitherto unknown bacterial protein that is crucial for mediating an interaction between the human pathogen H. influenzae and FH. This novel interaction is important for H. influenzae resistance against complement activation and will consequently promote bacterial pathogenesis.
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Affiliation(s)
- Christophe Fleury
- Medical Microbiology, Department of Laboratory Medicine Malmö, Lund University, SE-205 02 Malmö, Sweden
| | - Yu-Ching Su
- Medical Microbiology, Department of Laboratory Medicine Malmö, Lund University, SE-205 02 Malmö, Sweden
| | - Teresia Hallström
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Faculty of Biology, Friedrich Schiller University, 07745 Jena, Germany; and
| | - Linda Sandblad
- Department of Molecular Biology, Umeå University, SE-901 87 Umea, Sweden
| | - Peter F Zipfel
- Department of Infection Biology, Leibniz Institute for Natural Product Research and Infection Biology, Faculty of Biology, Friedrich Schiller University, 07745 Jena, Germany; and
| | - Kristian Riesbeck
- Medical Microbiology, Department of Laboratory Medicine Malmö, Lund University, SE-205 02 Malmö, Sweden;
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Brangulis K, Petrovskis I, Kazaks A, Bogans J, Otikovs M, Jaudzems K, Ranka R, Tars K. Structural characterization of CspZ, a complement regulator factor H and FHL-1 binding protein from Borrelia burgdorferi. FEBS J 2014; 281:2613-22. [PMID: 24702793 DOI: 10.1111/febs.12808] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 03/29/2014] [Accepted: 04/04/2014] [Indexed: 01/10/2023]
Abstract
Borrelia burgdorferi is the causative agent of Lyme disease and is found in two different types of hosts in nature - Ixodes ticks and various mammalian organisms. To initiate disease and survive in mammalian host organisms, B. burgdorferi must be able to transfer to a new host, proliferate, attach to different tissue and resist the immune response. To resist the host's immune response, B. burgdorferi produces at least five different outer surface proteins that can bind complement regulator factor H (CFH) and/or factor H-like protein 1 (CFHL-1). The crystal structures of two uniquely folded complement binding proteins, which belong to two distinct gene families and are not found in other bacteria, have been previously described. The crystal structure of the CFH and CFHL-1 binding protein CspZ (also known as BbCRASP-2 or BBH06) from B. burgdorferi, which belongs to a third gene family, is reported in this study. The structure reveals that the overall fold is different from the known structures of the other complement binding proteins in B. burgdorferi or other bacteria; this structure does not resemble the fold of any known protein deposited in the Protein Data Bank. The N-terminal part of the CspZ protein forms a four-helix bundle and has features similar to the FAT domain (focal adhesion targeting domain) and a related domain found in the vinculin/α-catenin family. By combining our findings from the crystal structure of CspZ with previous mutagenesis studies, we have identified a likely binding surface on CspZ for CFH and CFHL-1.
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Affiliation(s)
- Kalvis Brangulis
- Latvian Biomedical Research and Study Centre, Riga, Latvia; Riga Stradins University, Latvia
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Brissette CA, Gaultney RA. That's my story, and I'm sticking to it--an update on B. burgdorferi adhesins. Front Cell Infect Microbiol 2014; 4:41. [PMID: 24772392 PMCID: PMC3982108 DOI: 10.3389/fcimb.2014.00041] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 03/18/2014] [Indexed: 11/25/2022] Open
Abstract
Adhesion is the initial event in the establishment of any infection. Borrelia burgdorferi, the etiological agent of Lyme disease, possesses myriad proteins termed adhesins that facilitate contact with its vertebrate hosts. B. burgdorferi adheres to host tissues through interactions with host cells and extracellular matrix, as well as other molecules present in serum and extracellular fluids. These interactions, both general and specific, are critical in the establishment of infection. Modulation of borrelial adhesion to host tissues affects the microorganisms's ability to colonize, disseminate, and persist. In this review, we update the current knowledge on structure, function, and role in pathogenesis of these “sticky” B. burgdorferi infection-associated proteins.
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Affiliation(s)
- Catherine A Brissette
- Department of Basic Sciences, University of North Dakota School of Medicine and Health Sciences Grand Forks, ND, USA
| | - Robert A Gaultney
- Department of Basic Sciences, University of North Dakota School of Medicine and Health Sciences Grand Forks, ND, USA
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Versatile roles of CspA orthologs in complement inactivation of serum-resistant Lyme disease spirochetes. Infect Immun 2013; 82:380-92. [PMID: 24191298 DOI: 10.1128/iai.01094-13] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
CspA of the Lyme disease spirochete Borrelia burgdorferi represents a key molecule in immune evasion, protecting borrelial cells from complement-mediated killing. As previous studies focused almost exclusively on CspA of B. burgdorferi, here we investigate the different binding capacities of CspA orthologs of Borrelia burgdorferi, B. afzelii, and B. spielmanii for complement regulator factor H and plasminogen and their ability to inhibit complement activation by either binding these host-derived plasma proteins or independently by direct interaction with components involved in formation of the lethal, pore-like terminal complement complex. To further examine their function in serum resistance in vivo, a serum-sensitive B. garinii strain was used to generate spirochetes, ectopically producing functional CspA orthologs. Irrespective of their species origin, all three CspA orthologs impart resistance to complement-mediated killing when produced in a serum-sensitive B. garinii surrogate strain. To analyze the inhibitory effect on complement activation and to assess the potential to inactivate C3b by binding of factor H and plasminogen, recombinant CspA orthologs were also investigated. All three CspA orthologs simultaneously bound factor H and plasminogen but differed in regard to their capacity to inactivate C3b via bound plasmin(ogen) and inhibit formation of the terminal complement complex. CspA of B. afzelii binds plasmin(ogen) and inhibits the terminal complement complex more efficiently than CspA of B. burgdorferi and B. spielmanii. Taken together, CspA orthologs of serum-resistant Lyme disease spirochetes act as multifunctional evasion molecules that inhibit complement on two central activation levels, C3b generation and assembly of the terminal complement complex.
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