1
|
Colón Pérez J, Villarino Fernández RA, Domínguez Lago A, Treviño Castellano MM, Pérez del Molino Bernal ML, Sánchez Poza S, Torres-Sangiao E. Addressing Sexually Transmitted Infections Due to Neisseria gonorrhoeae in the Present and Future. Microorganisms 2024; 12:884. [PMID: 38792714 PMCID: PMC11124187 DOI: 10.3390/microorganisms12050884] [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: 03/19/2024] [Revised: 04/16/2024] [Accepted: 04/22/2024] [Indexed: 05/26/2024] Open
Abstract
It was in the 1800s when the first public publications about the infection and treatment of gonorrhoea were released. However, the first prevention programmes were only published a hundred years later. In the 1940s, the concept of vaccination was introduced into clinical prevention programmes to address early sulphonamide resistance. Since then, tons of publications on Neisseria gonorrhoeae are undisputed, around 30,000 publications today. Currently, the situation seems to be just as it was in the last century, nothing has changed or improved. So, what are we doing wrong? And more importantly, what might we do? The review presented here aims to review the current situation regarding the resistance mechanisms, prevention programmes, treatments, and vaccines, with the challenge of better understanding this special pathogen. The authors have reviewed the last five years of advancements, knowledge, and perspectives for addressing the Neisseria gonorrhoeae issue, focusing on new therapeutic alternatives.
Collapse
Affiliation(s)
- Julia Colón Pérez
- Servicio de Microbiología y Parasitología Clínica, Complexo Hospitalario Universitario de Santiago de Compostela, 15706 Santiago de Compostela, Spain; (J.C.P.); (A.D.L.); (M.M.T.C.); (M.L.P.d.M.B.)
- Grupo Microbiología, Instituto de Investigación Sanitaria de Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - Rosa-Antía Villarino Fernández
- Departamento de Microbiología, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain;
| | - Adrián Domínguez Lago
- Servicio de Microbiología y Parasitología Clínica, Complexo Hospitalario Universitario de Santiago de Compostela, 15706 Santiago de Compostela, Spain; (J.C.P.); (A.D.L.); (M.M.T.C.); (M.L.P.d.M.B.)
- Grupo Microbiología, Instituto de Investigación Sanitaria de Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - María Mercedes Treviño Castellano
- Servicio de Microbiología y Parasitología Clínica, Complexo Hospitalario Universitario de Santiago de Compostela, 15706 Santiago de Compostela, Spain; (J.C.P.); (A.D.L.); (M.M.T.C.); (M.L.P.d.M.B.)
- Grupo Microbiología, Instituto de Investigación Sanitaria de Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - María Luisa Pérez del Molino Bernal
- Servicio de Microbiología y Parasitología Clínica, Complexo Hospitalario Universitario de Santiago de Compostela, 15706 Santiago de Compostela, Spain; (J.C.P.); (A.D.L.); (M.M.T.C.); (M.L.P.d.M.B.)
- Grupo Microbiología, Instituto de Investigación Sanitaria de Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| | - Sandra Sánchez Poza
- Departamento de Microbiología, Facultad de Farmacia, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain;
| | - Eva Torres-Sangiao
- Servicio de Microbiología y Parasitología Clínica, Complexo Hospitalario Universitario de Santiago de Compostela, 15706 Santiago de Compostela, Spain; (J.C.P.); (A.D.L.); (M.M.T.C.); (M.L.P.d.M.B.)
- Grupo Microbiología, Instituto de Investigación Sanitaria de Santiago de Compostela (IDIS), 15706 Santiago de Compostela, Spain
| |
Collapse
|
2
|
Sándor N, Schneider AE, Matola AT, Barbai VH, Bencze D, Hammad HH, Papp A, Kövesdi D, Uzonyi B, Józsi M. The human factor H protein family - an update. Front Immunol 2024; 15:1135490. [PMID: 38410512 PMCID: PMC10894998 DOI: 10.3389/fimmu.2024.1135490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 01/08/2024] [Indexed: 02/28/2024] Open
Abstract
Complement is an ancient and complex network of the immune system and, as such, it plays vital physiological roles, but it is also involved in numerous pathological processes. The proper regulation of the complement system is important to allow its sufficient and targeted activity without deleterious side-effects. Factor H is a major complement regulator, and together with its splice variant factor H-like protein 1 and the five human factor H-related (FHR) proteins, they have been linked to various diseases. The role of factor H in inhibiting complement activation is well studied, but the function of the FHRs is less characterized. Current evidence supports the main role of the FHRs as enhancers of complement activation and opsonization, i.e., counter-balancing the inhibitory effect of factor H. FHRs emerge as soluble pattern recognition molecules and positive regulators of the complement system. In addition, factor H and some of the FHR proteins were shown to modulate the activity of immune cells, a non-canonical function outside the complement cascade. Recent efforts have intensified to study factor H and the FHRs and develop new tools for the distinction, quantification and functional characterization of members of this protein family. Here, we provide an update and overview on the versatile roles of factor H family proteins, what we know about their biological functions in healthy conditions and in diseases.
Collapse
Affiliation(s)
- Noémi Sándor
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
- HUN-REN-ELTE Complement Research Group, Hungarian Research Network, Budapest, Hungary
| | | | | | - Veronika H. Barbai
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Dániel Bencze
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Hani Hashim Hammad
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Alexandra Papp
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Dorottya Kövesdi
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
- HUN-REN-ELTE Complement Research Group, Hungarian Research Network, Budapest, Hungary
| | - Barbara Uzonyi
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
- HUN-REN-ELTE Complement Research Group, Hungarian Research Network, Budapest, Hungary
| | - Mihály Józsi
- Department of Immunology, ELTE Eötvös Loránd University, Budapest, Hungary
- HUN-REN-ELTE Complement Research Group, Hungarian Research Network, Budapest, Hungary
| |
Collapse
|
3
|
Heggi MT, Nour El-Din HT, Morsy DI, Abdelaziz NI, Attia AS. Microbial evasion of the complement system: a continuous and evolving story. Front Immunol 2024; 14:1281096. [PMID: 38239357 PMCID: PMC10794618 DOI: 10.3389/fimmu.2023.1281096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 11/30/2023] [Indexed: 01/22/2024] Open
Abstract
The complement system is a fundamental part of the innate immune system that plays a key role in the battle of the human body against invading pathogens. Through its three pathways, represented by the classical, alternative, and lectin pathways, the complement system forms a tightly regulated network of soluble proteins, membrane-expressed receptors, and regulators with versatile protective and killing mechanisms. However, ingenious pathogens have developed strategies over the years to protect themselves from this complex part of the immune system. This review briefly discusses the sequence of the complement activation pathways. Then, we present a comprehensive updated overview of how the major four pathogenic groups, namely, bacteria, viruses, fungi, and parasites, control, modulate, and block the complement attacks at different steps of the complement cascade. We shed more light on the ability of those pathogens to deploy more than one mechanism to tackle the complement system in their path to establish infection within the human host.
Collapse
Affiliation(s)
- Mariam T. Heggi
- Clinical Pharmacy Undergraduate Program, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Hanzada T. Nour El-Din
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | | | | | - Ahmed S. Attia
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| |
Collapse
|
4
|
Zhao M, Zhu Y, Wang H, Zhang W, Mu W. Recent advances on N-acetylneuraminic acid: Physiological roles, applications, and biosynthesis. Synth Syst Biotechnol 2023; 8:509-519. [PMID: 37502821 PMCID: PMC10369400 DOI: 10.1016/j.synbio.2023.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 06/22/2023] [Accepted: 06/27/2023] [Indexed: 07/29/2023] Open
Abstract
N-Acetylneuraminic acid (Neu5Ac), the most common type of Sia, generally acts as the terminal sugar in cell surface glycans, glycoconjugates, oligosaccharides, lipo-oligosaccharides, and polysaccharides, thus exerting numerous physiological functions. The extensive applications of Neu5Ac in the food, cosmetic, and pharmaceutical industries make large-scale production of this chemical desirable. Biosynthesis which is associated with important application potential and environmental friendliness has become an indispensable approach for large-scale synthesis of Neu5Ac. In this review, the physiological roles of Neu5Ac was first summarized in detail. Second, the safety evaluation, regulatory status, and applications of Neu5Ac were discussed. Third, enzyme-catalyzed preparation, whole-cell biocatalysis, and microbial de novo synthesis of Neu5Ac were comprehensively reviewed. In addition, we discussed the main challenges of Neu5Ac de novo biosynthesis, such as screening and engineering of key enzymes, identifying exporters of intermediates and Neu5Ac, and balancing cell growth and biosynthesis. The corresponding strategies and systematic strategies were proposed to overcome these challenges and facilitate Neu5Ac industrial-scale production.
Collapse
Affiliation(s)
- Mingli Zhao
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, PR China
| | - Yingying Zhu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, PR China
| | - Hao Wang
- Bloomage Biotechnology Corp., Ltd., Jinan, Shandong, 250010, PR China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, PR China
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu, 214122, PR China
| |
Collapse
|
5
|
Girgis MM, Christodoulides M. Vertebrate and Invertebrate Animal and New In Vitro Models for Studying Neisseria Biology. Pathogens 2023; 12:782. [PMID: 37375472 DOI: 10.3390/pathogens12060782] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/03/2023] [Accepted: 05/18/2023] [Indexed: 06/29/2023] Open
Abstract
The history of Neisseria research has involved the use of a wide variety of vertebrate and invertebrate animal models, from insects to humans. In this review, we itemise these models and describe how they have made significant contributions to understanding the pathophysiology of Neisseria infections and to the development and testing of vaccines and antimicrobials. We also look ahead, briefly, to their potential replacement by complex in vitro cellular models.
Collapse
Affiliation(s)
- Michael M Girgis
- Neisseria Research Group, Molecular Microbiology, School of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
- Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt
| | - Myron Christodoulides
- Neisseria Research Group, Molecular Microbiology, School of Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
| |
Collapse
|
6
|
Shaughnessy J, Chabeda A, Tran Y, Zheng B, Nowak N, Steffens C, DeOliveira RB, Gulati S, Lewis LA, Maclean J, Moss JA, Wycoff KL, Ram S. An optimized Factor H-Fc fusion protein against multidrug-resistant Neisseria gonorrhoeae. Front Immunol 2022; 13:975676. [PMID: 36110842 PMCID: PMC9468773 DOI: 10.3389/fimmu.2022.975676] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
Novel therapeutics against the global threat of multidrug-resistant Neisseria gonorrhoeae are urgently needed. Gonococci evade killing by complement by binding factor H (FH), a key inhibitor of the alternative pathway. FH comprises 20 short consensus repeat (SCR) domains organized as a single chain. Gonococci bind FH through domains 6 and 7, and C-terminal domains 18 through 20. Previously, we showed that a chimeric protein comprising (from the N- to C-terminus) FH domains 18-20 (containing a point mutation in domain 19 to prevent lysis of host cells) fused to human IgG1 Fc (called FH*/Fc1) killed gonococci in a complement-dependent manner and reduced the duration and bacterial burden in the mouse vaginal colonization model of gonorrhea. Considering the N. gonorrhoeae-binding FH domains 18-20 are C-terminal in native FH, we reasoned that positioning Fc N-terminal to FH* (Fc1/FH*) would improve binding and bactericidal activity. Although both molecules bound gonococci similarly, Fc1/FH* displayed a 5-fold lower IC50 (the concentration required for 50% killing in complement-dependent bactericidal assays) than FH*/Fc1. To further increase complement activation, we replaced human IgG1 Fc in Fc1/FH* with Fc from human IgG3, the most potent complement-activating IgG subclass, to obtain Fc3/FH*. Bactericidal activity was further increased ~2.3-fold in Fc3/FH* compared to Fc1/FH*. Fc3/FH* killed (defined by <50% survival) 45/45 (100%) diverse PorB1B-expessing gonococci, but only 2/15 PorB1A-expressing isolates, in a complement-dependent manner. Decreased Fc3/FH* binding accounted for the limited activity against PorB1A strains. Fc3/FH* was efficacious against all four tested PorB1B gonococcal strains in the mouse vaginal colonization model when administered at a dose of 5 µg intravaginally, daily. Furthermore, Fc3/FH* retained bactericidal activity when reconstituted following lyophilization or spray-drying, suggesting feasibility for formulation into intravaginal rings. In conclusion, Fc3/FH* represents a promising prophylactic immunotherapeutic against multidrug-resistant gonococci.
Collapse
Affiliation(s)
- Jutamas Shaughnessy
- Division of Infectious Diseases and Immunology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Aleyo Chabeda
- Division of Infectious Diseases and Immunology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Y. Tran
- Planet Biotechnology, Inc., Hayward, CA, United States
| | - Bo Zheng
- Division of Infectious Diseases and Immunology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Nancy Nowak
- Division of Infectious Diseases and Immunology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Carolynn Steffens
- Division of Infectious Diseases and Immunology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Rosane B. DeOliveira
- Division of Infectious Diseases and Immunology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Sunita Gulati
- Division of Infectious Diseases and Immunology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - Lisa A. Lewis
- Division of Infectious Diseases and Immunology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| | - James Maclean
- Planet Biotechnology, Inc., Hayward, CA, United States
| | - John A. Moss
- Oak Crest Institute of Science, Monrovia, CA, United States
| | | | - Sanjay Ram
- Division of Infectious Diseases and Immunology, University of Massachusetts Chan Medical School, Worcester, MA, United States
| |
Collapse
|
7
|
Hota S, Hussain MS, Kumar M. ErpY-like Lipoprotein of Leptospira Outsmarts Host Complement Regulation by Acquiring Complement Regulators, Activating Alternative Pathways, and Intervening in the Membrane Attack Complex. ACS Infect Dis 2022; 8:982-997. [PMID: 35422118 DOI: 10.1021/acsinfecdis.1c00602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The survival of pathogenic Leptospira in the host depends on its proficiency to circumvent the immune response. These pathogens evade the complement system in serum by enticing and amassing the serum complement regulators onto their surface. ErpY-like lipoprotein, a surface-exposed protein of Leptospira spp., is conserved in the pathogenic Leptospira serovars. The recombinant form of this protein interacts with multiple extracellular matrix (ECM) components and serum proteins such as soluble complement regulators factor H (FH) and factor I (FI). Here, we document that the supplementation of rErpY-like protein (10 μg/mL) in human serum inhibits complement-mediated bacterial cell lysis and augments the viability of Escherichia coli and saprophytic Leptospira biflexa by more than two-fold. Complement regulators FH and FI, when bound to rErpY-like protein, preserve their respective cofactor and protease activity and cleave the complement component C3b. The supplementation of rErpY-like protein (40 μg/mL) in serum ensued in an ∼90% reduction of membrane attack complex (C5b-9/MAC) deposition through the alternative pathway (AP) of complement activation. However, rErpY-like protein could moderately reduce (∼16%) MAC deposition in serum through the classical pathway (CP). In addition, the rErpY-like protein solely initiated the AP, suggesting its role in the rapid consumption and depletion of the complement components. Blocking the pathogenic Leptospira interrogans surface with anti-rErpY-like antibodies resulted in an increase in MAC formation on the bacterial surface, indicating a specific role of the ErpY-like lipoprotein in complement-mediated immune evasion. This study underscores the role of the ErpY-like lipoprotein of Leptospira in complement evasion.
Collapse
Affiliation(s)
- Saswat Hota
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Md Saddam Hussain
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Manish Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| |
Collapse
|
8
|
A Factor H-Fc fusion protein increases complement-mediated opsonophagocytosis and killing of community associated methicillin-resistant Staphylococcus aureus. PLoS One 2022; 17:e0265774. [PMID: 35324969 PMCID: PMC8946749 DOI: 10.1371/journal.pone.0265774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 03/07/2022] [Indexed: 11/19/2022] Open
Abstract
Staphylococcus aureus employs a multitude of immune-evasive tactics to circumvent host defenses including the complement system, a component of innate immunity central to controlling bacterial infections. With antibiotic resistance becoming increasingly common, there is a dire need for novel therapies. Previously, we have shown that S. aureus binds the complement regulator factor H (FH) via surface protein SdrE to inhibit complement. To address the need for novel therapeutics and take advantage of the FH:SdrE interaction, we examined the effect of a fusion protein comprised of the SdrE-interacting domain of FH coupled with IgG Fc on complement-mediated opsonophagocytosis and bacterial killing of community associated methicillin-resistant S. aureus. S. aureus bound significantly more FH-Fc compared to Fc-control proteins and FH-Fc competed with serum FH for S. aureus binding. FH-Fc treatment increased C3-fragment opsonization of S. aureus for both C3b and iC3b, and boosted generation of the anaphylatoxin C5a. In 5 and 10% serum, FH-Fc treatment significantly increased S. aureus killing by polymorphonuclear cells. This anti-staphylococcal effect was evident in 75% (3/4) of clinical isolates tested. This study demonstrates that FH-Fc fusion proteins have the potential to mitigate the protective effects of bound serum FH rendering S. aureus more vulnerable to the host immune system. Thus, we report the promise of virulence-factor-targeted fusion-proteins as an avenue for prospective anti-staphylococcal therapeutic development.
Collapse
|
9
|
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.
Collapse
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.
| |
Collapse
|
10
|
Gulati S, Schoenhofen IC, Lindhout-Djukic T, Lewis LA, Moustafa IY, Saha S, Zheng B, Nowak N, Rice PA, Varki A, Ram S. Efficacy of Antigonococcal CMP-Nonulosonate Therapeutics Require Cathelicidins. J Infect Dis 2021; 222:1641-1650. [PMID: 32692363 DOI: 10.1093/infdis/jiaa438] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 07/15/2020] [Indexed: 12/21/2022] Open
Abstract
Novel therapies to counteract multidrug-resistant gonorrhea are urgently needed. A unique gonococcal immune evasion strategy involves capping of lipooligosaccharide (LOS) with sialic acid by gonococcal sialyltransferase (Lst), utilizing host-derived CMP-sialic acid (CMP-Neu5Ac in humans). LOS sialylation renders gonococci resistant to complement and cationic peptides, and down-regulates the inflammatory response by engaging siglecs. CMP-sialic acid analogs (CMP-nonulosonates [CMP-NulOs]) such as CMP-Leg5,7Ac2 and CMP-Kdn are also utilized by Lst. Incorporation of these NulO analogs into LOS maintains gonococci susceptible to complement. Intravaginal administration of CMP-Kdn or CMP-Leg5,7Ac2 attenuates gonococcal colonization of mouse vaginas. Here, we identify a key mechanism of action for the efficacy of CMP-NulOs. Surprisingly, CMP-NulOs remained effective in complement C1q-/- and C3-/- mice. LOS Neu5Ac, but not Leg5,7Ac2 or Kdn, conferred resistance to the cathelicidins LL-37 (human) and mouse cathelicidin-related antimicrobial peptide in vitro. CMP-NulOs were ineffective in Camp-/- mice, revealing that cathelicidins largely mediate the efficacy of therapeutic CMP-NulOs.
Collapse
Affiliation(s)
- Sunita Gulati
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Ian C Schoenhofen
- Human Health Therapeutics Research Centre, National Research Council of Canada, Ottawa, Ontario, Canada
| | - Theresa Lindhout-Djukic
- Human Health Therapeutics Research Centre, National Research Council of Canada, Ottawa, Ontario, Canada
| | - Lisa A Lewis
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Iesha Y Moustafa
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Sudeshna Saha
- Department of Medicine and Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, California, USA
| | - Bo Zheng
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Nancy Nowak
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Peter A Rice
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Ajit Varki
- Department of Medicine and Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, California, USA
| | - Sanjay Ram
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| |
Collapse
|
11
|
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: 44] [Impact Index Per Article: 14.7] [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.
Collapse
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
| |
Collapse
|
12
|
Gulati S, Schoenhofen IC, Lindhout-Djukic T, Schur MJ, Landig CS, Saha S, Deng L, Lewis LA, Zheng B, Varki A, Ram S. Therapeutic CMP-Nonulosonates against Multidrug-Resistant Neisseria gonorrhoeae. THE JOURNAL OF IMMUNOLOGY 2020; 204:3283-3295. [PMID: 32434942 DOI: 10.4049/jimmunol.1901398] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 04/08/2020] [Indexed: 12/29/2022]
Abstract
Neisseria gonorrhoeae deploys a unique immune evasion strategy wherein the lacto-N-neotetraose termini of lipooligosaccharide (LOS) are "capped" by a surface LOS sialyltransferase (Lst), using extracellular host-derived CMP-sialic acid (CMP-Neu5Ac in humans). LOS sialylation enhances complement resistance by recruiting factor H (FH; alternative complement pathway inhibitor) and also by limiting classical pathway activation. Sialylated LOS also engages inhibitory Siglecs on host leukocytes, dampening innate immunity. Previously, we showed that analogues of CMP-sialic acids (CMP-nonulosonates [CMP-NulOs]), such as CMP-Leg5,7Ac2 and CMP-Neu5Ac9N3, are also substrates for Lst. Incorporation of Leg5,7Ac2 and Neu5Ac9N3 into LOS results in N. gonorrhoeae being fully serum sensitive. Importantly, intravaginal administration of CMP-Leg5,7Ac2 attenuated N. gonorrhoeae colonization of mouse vaginas. In this study, we characterize and develop additional candidate therapeutic CMP-NulOs. CMP-ketodeoxynonulosonate (CMP-Kdn) and CMP-Kdn7N3, but not CMP-Neu4,5Ac2, were substrates for Lst, further elucidating gonococcal Lst specificity. Lacto-N-neotetraose LOS capped with Kdn and Kdn7N3 bound FH to levels ∼60% of that seen with Neu5Ac and enabled gonococci to resist low (3.3%) but not higher (10%) concentrations of human complement. CMP-Kdn, CMP-Neu5Ac9N3, and CMP-Leg5,7Ac2 administered intravaginally (10 μg/d) to N. gonorrhoeae-colonized mice were equally efficacious. Of the three CMP-NulOs above, CMP-Leg5,7Ac2 was the most pH and temperature stable. In addition, Leg5,7Ac2-fed human cells did not display this NulO on their surface. Moreover, CMP-Leg5,7Ac2 was efficacious against several multidrug-resistant gonococci in mice with a humanized sialome (Cmah-/- mice) or humanized complement system (FH/C4b-binding protein transgenic mice). CMP-Leg5,7Ac2 and CMP-Kdn remain viable leads as topical preventive/therapeutic agents against the global threat of multidrug-resistant N. gonorrhoeae.
Collapse
Affiliation(s)
- Sunita Gulati
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Ian C Schoenhofen
- Human Health Therapeutics Research Centre, National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada;
| | - Theresa Lindhout-Djukic
- Human Health Therapeutics Research Centre, National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada
| | - Melissa J Schur
- Human Health Therapeutics Research Centre, National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada
| | - Corinna S Landig
- Department of Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093; and.,Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093
| | - Sudeshna Saha
- Department of Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093; and.,Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093
| | - Lingquan Deng
- Department of Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093; and.,Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093
| | - Lisa A Lewis
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Bo Zheng
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605
| | - Ajit Varki
- Department of Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093; and.,Department of Cellular and Molecular Medicine, Glycobiology Research and Training Center, University of California, San Diego, La Jolla, CA 92093
| | - Sanjay Ram
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605;
| |
Collapse
|
13
|
Complement Evasion Strategies of Human Pathogenic Bacteria. Indian J Microbiol 2020; 60:283-296. [PMID: 32655196 DOI: 10.1007/s12088-020-00872-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 04/07/2020] [Indexed: 12/21/2022] Open
Abstract
Human pathogens need to overcome an elaborate network of host defense mechanisms in order to establish their infection, colonization, proliferation and eventual dissemination. The interaction of pathogens with different effector molecules of the immune system results in their neutralization and elimination from the host. The complement system is one such integral component of innate immunity that is critically involved in the early recognition and elimination of the pathogen. Hence, under this immune pressure, all virulent pathogens capable of inducing active infections have evolved immune evasive strategies that primarily target the complement system, which plays an essential and central role for host defense. Recent reports on several bacterial pathogens have elucidated the molecular mechanisms underlying complement evasion, inhibition of opsonic phagocytosis and cell lysis. This review aims to comprehensively summarize the recent findings on the various strategies adopted by pathogenic bacteria to escape complement-mediated clearance.
Collapse
|
14
|
Lewis LA, Ram S. Complement interactions with the pathogenic Neisseriae: clinical features, deficiency states, and evasion mechanisms. FEBS Lett 2020; 594:2670-2694. [PMID: 32058583 DOI: 10.1002/1873-3468.13760] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 02/04/2020] [Accepted: 02/09/2020] [Indexed: 02/06/2023]
Abstract
Neisseria gonorrhoeae causes the sexually transmitted infection gonorrhea, while Neisseria meningitidis is an important cause of bacterial meningitis and sepsis. Complement is a central arm of innate immune defenses and plays an important role in combating Neisserial infections. Persons with congenital and acquired defects in complement are at a significantly higher risk for invasive Neisserial infections such as invasive meningococcal disease and disseminated gonococcal infection compared to the general population. Of note, Neisseria gonorrhoeae and Neisseria meningitidis can only infect humans, which in part may be related to their ability to evade only human complement. This review summarizes the epidemiologic and clinical aspects of Neisserial infections in persons with defects in the complement system. Mechanisms used by these pathogens to subvert killing by complement and preclinical studies showing how these complement evasion strategies may be used to counteract the global threat of meningococcal and gonococcal infections are discussed.
Collapse
Affiliation(s)
- Lisa A Lewis
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Sanjay Ram
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, USA
| |
Collapse
|
15
|
Dopler A, Guntau L, Harder MJ, Palmer A, Höchsmann B, Schrezenmeier H, Simmet T, Huber-Lang M, Schmidt CQ. Response to Comment on "Self versus Nonself Discrimination by the Soluble Complement Regulators Factor H and FHL-1". JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2019; 203:2029-2030. [PMID: 31591258 DOI: 10.4049/jimmunol.1900994] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Affiliation(s)
- Arthur Dopler
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, 89081 Ulm, Germany
| | - Leonie Guntau
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, 89081 Ulm, Germany
| | - Markus J Harder
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, 89081 Ulm, Germany
| | - Annette Palmer
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital Ulm, 89081 Ulm, Germany
| | - Britta Höchsmann
- Institute of Transfusion Medicine, University of Ulm, 89081 Ulm, Germany; and
- Institute for Clinical Transfusion Medicine and Immunogenetics, German Red Cross Blood Transfusion Service Baden-Wurttemberg-Hessen and University Hospital, 89081 Ulm, Germany
| | - Hubert Schrezenmeier
- Institute of Transfusion Medicine, University of Ulm, 89081 Ulm, Germany; and
- Institute for Clinical Transfusion Medicine and Immunogenetics, German Red Cross Blood Transfusion Service Baden-Wurttemberg-Hessen and University Hospital, 89081 Ulm, Germany
| | - Thomas Simmet
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, 89081 Ulm, Germany
| | - Markus Huber-Lang
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital Ulm, 89081 Ulm, Germany
| | - Christoph Q Schmidt
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, 89081 Ulm, Germany;
| |
Collapse
|
16
|
Ermert D, Ram S, Laabei M. The hijackers guide to escaping complement: Lessons learned from pathogens. Mol Immunol 2019; 114:49-61. [PMID: 31336249 DOI: 10.1016/j.molimm.2019.07.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 07/15/2019] [Accepted: 07/16/2019] [Indexed: 02/07/2023]
Abstract
Pathogens that invade the human host are confronted by a multitude of defence mechanisms aimed at preventing colonization, dissemination and proliferation. The most frequent outcome of this interaction is microbial elimination, in which the complement system plays a major role. Complement, an essential feature of the innate immune machinery, rapidly identifies and marks pathogens for efficient removal. Consequently, this creates a selective pressure for microbes to evolve strategies to combat complement, permitting host colonization and access to resources. All successful pathogens have developed mechanisms to resist complement activity which are intimately aligned with their capacity to cause disease. In this review, we describe the successful methods various pathogens use to evade complement activation, shut down inflammatory signalling through complement, circumvent opsonisation and override terminal pathway lysis. This review summarizes how pathogens undermine innate immunity: 'The Hijackers Guide to Complement'.
Collapse
Affiliation(s)
- David Ermert
- Department of Preclinical Research, BioInvent International AB, Lund, Sweden; Department of Translational Medicine, Division of Medical Protein Chemistry, Lund University, Malmö, Sweden
| | - Sanjay Ram
- Department of Medicine, Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Maisem Laabei
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom.
| |
Collapse
|
17
|
Allen LAH, Criss AK. Cell intrinsic functions of neutrophils and their manipulation by pathogens. Curr Opin Immunol 2019; 60:124-129. [PMID: 31302568 DOI: 10.1016/j.coi.2019.05.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/30/2019] [Accepted: 05/11/2019] [Indexed: 12/13/2022]
Abstract
Neutrophils are a crucial first line of defense against infection, migrating rapidly into tissues where they deploy granule components and toxic oxidants for efficient phagocytosis and microbe killing. Subsequent apoptosis and clearance of dying neutrophils are essential for control of infection and resolution of the inflammatory response. A subset of microbial pathogens survive exposure to neutrophils by manipulating phagocytosis, phagosome-granule fusion, oxidant production, and lifespan. Elucidating how they accomplish this unusual feat provides new insights into normal neutrophil function. In this review, we highlight recent discoveries about the ways in which neutrophils use cell-intrinsic mechanisms to control infection, and how these defenses are subverted by pathogens.
Collapse
Affiliation(s)
- Lee-Ann H Allen
- Department of Microbiology and Immunology and Department of Medicine, University of Iowa, Iowa City, IA 52242, United States; The Iowa City VA Health Care System, Iowa City, IA 52246, United States
| | - Alison K Criss
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA 22908-0734, United States.
| |
Collapse
|
18
|
Cristillo AD, Bristow CC, Torrone E, Dillon JA, Kirkcaldy RD, Dong H, Grad YH, Nicholas RA, Rice PA, Lawrence K, Oldach D, Shafer WM, Zhou P, Wi TE, Morris SR, Klausner JD. Antimicrobial Resistance in Neisseria gonorrhoeae: Proceedings of the STAR Sexually Transmitted Infection-Clinical Trial Group Programmatic Meeting. Sex Transm Dis 2019; 46:e18-e25. [PMID: 30363025 PMCID: PMC6370498 DOI: 10.1097/olq.0000000000000929] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 10/01/2018] [Indexed: 11/27/2022]
Abstract
The goal of the Sexually Transmitted Infection Clinical Trial Group's Antimicrobial Resistance (AMR) in Neisseria gonorrhoeae (NG) meeting was to assemble experts from academia, government, nonprofit and industry to discuss the current state of research, gaps and challenges in research and technology and priorities and new directions to address the continued emergence of multidrug-resistant NG infections. Topics discussed at the meeting, which will be the focus of this article, include AMR NG global surveillance initiatives, the use of whole genome sequencing and bioinformatics to understand mutations associated with AMR, mechanisms of AMR, and novel antibiotics, vaccines and other methods to treat AMR NG. Key points highlighted during the meeting include: (i) US and International surveillance programs to understand AMR in NG; (ii) the US National Strategy for combating antimicrobial-resistant bacteria; (iii) surveillance needs, challenges, and novel technologies; (iv) plasmid-mediated and chromosomally mediated mechanisms of AMR in NG; (v) novel therapeutic (eg, sialic acid analogs, factor H [FH]/Fc fusion molecule, monoclonal antibodies, topoisomerase inhibitors, fluoroketolides, LpxC inhibitors) and preventative (eg, peptide mimic) strategies to combat infection. The way forward will require renewed political will, new funding initiatives, and collaborations across academic and commercial research and public health programs.
Collapse
Affiliation(s)
- Anthony D. Cristillo
- From the Department of Clinical Research and Bioscience Social & Scientific Systems, Inc., Silver Spring, MD
| | - Claire C. Bristow
- Department of Medicine, University of California San Diego School of Medicine, La Jolla, CA
| | - Elizabeth Torrone
- Division of STD Prevention, US Centers for Disease Control and Prevention (CDC), Atlanta, GA
| | - Jo-Anne Dillon
- Department of Microbiology and Immunology, College of Medicine, University of Saskatchewan, Saskatchewan, Canada
| | - Robert D. Kirkcaldy
- Division of STD Prevention, US Centers for Disease Control and Prevention (CDC), Atlanta, GA
| | - Huan Dong
- Charles R. Drew University of Medicine and Sciences, Los Angeles, CA
- David Geffen School of Medicine at University of California, Los Angeles, CA
| | - Yonatan H. Grad
- Department of Immunology and Infectious Diseases, Harvard University T.H. Chan School of Public Health, Boston, MA
| | - Robert A. Nicholas
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Peter A. Rice
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA
| | | | | | - William Maurice Shafer
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta
- Veterans Affairs Medical Center, Decatur, GA
| | - Pei Zhou
- Department of Biochemistry, Duke University Medical Center, Durham, NC; and
| | - Teodora E. Wi
- Department of Reproductive Health and Research, World Health Organization, Geneva, Switzerland; and
| | - Sheldon R. Morris
- Department of Medicine, University of California San Diego School of Medicine, La Jolla, CA
| | - Jeffrey D. Klausner
- Division of Infectious Diseases, University of California, Los Angeles, Los Angeles, CA
| |
Collapse
|
19
|
Role of Gonococcal Neisserial Surface Protein A (NspA) in Serum Resistance and Comparison of Its Factor H Binding Properties with Those of Its Meningococcal Counterpart. Infect Immun 2019; 87:IAI.00658-18. [PMID: 30510105 DOI: 10.1128/iai.00658-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Accepted: 11/25/2018] [Indexed: 01/15/2023] Open
Abstract
Neisseria gonorrhoeae, the causative agent of gonorrhea, has evolved several mechanisms to subvert complement, including binding of the complement inhibitor factor H (FH). We previously reported FH binding to N. gonorrhoeae independently of lipooligosaccharide (LOS) sialylation. Here we report that factor H-like protein 1 (FHL-1), which contains FH domains 1 through 7 and possesses complement-inhibitory activity, also binds to N. gonorrhoeae The ligand for both FH and FHL-1 was identified as neisserial surface protein A (NspA), which has previously been identified as a ligand for these molecules on Neisseria meningitidis As with N. meningitidis NspA (Nm-NspA), N. gonorrhoeae NspA (Ng-NspA) bound FH/FHL-1 through FH domains 6 and 7. Binding of FH/FHL-1 to NspA was human specific; the histidine (H) at position 337 of domain 6 contributed to human-specific FH binding to both Ng- and Nm-NspA. FH/FHL-1 bound Nm-NspA better than Ng-NspA; introducing Q at position 73 (loop 2, present in Ng-NspA) or replacing V and D at positions 112 and 113 in Nm-NspA loop 3 with A and H (Ng-NspA), respectively, reduced FH/FHL-1 binding. The converse Ng-NspA to Nm-NspA mutations increased FH/FHL-1 binding. Binding of FH/FHL-1 through domains 6 and 7 to N. gonorrhoeae increased with truncation of the heptose I (HepI) chain of LOS and decreased with LOS sialylation. Loss of NspA significantly decreased serum resistance of N. gonorrhoeae with either wild-type or truncated LOS. This report highlights the role for NspA in enabling N. gonorrhoeae to subvert complement despite LOS phase variation. Knowledge of FH-NspA interactions will inform the design of vaccines and immunotherapies against the global threat of multidrug-resistant gonorrhea.
Collapse
|
20
|
Abstract
Neisseria gonorrhoeae infection is a major public health problem worldwide. The increasing incidence of gonorrhea coupled with global spread of multidrug-resistant isolates of gonococci has ushered in an era of potentially untreatable infection. Gonococcal disease elicits limited immunity, and individuals are susceptible to repeated infections. In this chapter, we describe gonococcal disease and epidemiology and the structure and function of major surface components involved in pathogenesis. We also discuss the mechanisms that gonococci use to evade host immune responses and the immune responses following immunization with selected bacterial components that may overcome evasion. Understanding the biology of the gonococcus may aid in preventing the spread of gonorrhea and also facilitate the development of gonococcal vaccines and treatments.
Collapse
Affiliation(s)
- Jutamas Shaughnessy
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Sanjay Ram
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Peter A Rice
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA.
| |
Collapse
|
21
|
Shaughnessy J, Lewis LA, Zheng B, Carr C, Bass I, Gulati S, DeOliveira RB, Gose S, Reed GW, Botto M, Rice PA, Ram S. Human Factor H Domains 6 and 7 Fused to IgG1 Fc Are Immunotherapeutic against Neisseria gonorrhoeae. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2018; 201:2700-2709. [PMID: 30266769 PMCID: PMC6200640 DOI: 10.4049/jimmunol.1701666] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 08/27/2018] [Indexed: 01/15/2023]
Abstract
Novel therapeutics against multidrug-resistant Neisseria gonorrhoeae are urgently needed. Gonococcal lipooligosaccharide often expresses lacto-N-neotetraose (LNnT), which becomes sialylated in vivo, enhancing factor H (FH) binding and contributing to the organism's ability to resist killing by complement. We previously showed that FH domains 18-20 (with a D-to-G mutation at position 1119 in domain 19) fused to Fc (FHD1119G/Fc) displayed complement-dependent bactericidal activity in vitro and attenuated gonococcal vaginal colonization of mice. Gonococcal lipooligosaccharide phase variation can result in loss of LNnT expression. Loss of sialylated LNnT, although associated with a considerable fitness cost, could decrease efficacy of FHD1119G/Fc. Similar to N. meningitidis, gonococci also bind FH domains 6 and 7 through Neisserial surface protein A (NspA). In this study, we show that a fusion protein comprising FH domains 6 and 7 fused to human IgG1 Fc (FH6,7/Fc) bound to 15 wild-type antimicrobial resistant isolates of N. gonorrhoeae and to each of six lgtA gonococcal deletion mutants. FH6,7/Fc mediated complement-dependent killing of 8 of the 15 wild-type gonococcal isolates and effectively reduced the duration and burden of vaginal colonization of three gonococcal strains tested in wild-type mice, including two strains that resisted complement-dependent killing but on which FH6,7/Fc enhanced C3 deposition. FH/Fc lost efficacy when Fc was mutated to abrogate C1q binding and in C1q-/- mice, highlighting the requirement of the classical pathway for its activity. Targeting gonococci with FH6,7/Fc provides an additional immunotherapeutic approach against multidrug-resistant gonorrhea.
Collapse
Affiliation(s)
- Jutamas Shaughnessy
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Lisa A Lewis
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Bo Zheng
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Caleb Carr
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Isaac Bass
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Sunita Gulati
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Rosane B DeOliveira
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Severin Gose
- San Francisco Department of Public Health, San Francisco, CA 94102; and
| | - George W Reed
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Marina Botto
- Faculty of Medicine, Imperial College London, London SW7 2AZ, United Kingdom
| | - Peter A Rice
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605
| | - Sanjay Ram
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605;
| |
Collapse
|
22
|
Saphire EO, Schendel SL, Gunn BM, Milligan JC, Alter G. Antibody-mediated protection against Ebola virus. Nat Immunol 2018; 19:1169-1178. [PMID: 30333617 DOI: 10.1038/s41590-018-0233-9] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 09/04/2018] [Indexed: 01/30/2023]
Abstract
Recent Ebola virus disease epidemics have highlighted the need for effective vaccines and therapeutics to prevent future outbreaks. Antibodies are clearly critical for control of this deadly disease; however, the specific mechanisms of action of protective antibodies have yet to be defined. In this Perspective we discuss the antibody features that correlate with in vivo protection during infection with Ebola virus, based on the results of a systematic and comprehensive study of antibodies directed against this virus. Although neutralization activity mediated by the Fab domains of the antibody is strongly correlated with protection, recruitment of immune effector functions by the Fc domain has also emerged as a complementary, and sometimes alternative, route to protection. For a subset of antibodies, Fc-mediated clearance and killing of infected cells seems to be the main driver of protection after exposure and mirrors observations in vaccination studies. Continued analysis of antibodies that achieve protection partially or wholly through Fc-mediated functions, the precise functions required, the intersection with specificity and the importance of these functions in different animal models is needed to identify and begin to capitalize on Fc-mediated protection in vaccines and therapeutics alike.
Collapse
Affiliation(s)
- Erica Ollmann Saphire
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA. .,Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA.
| | - Sharon L Schendel
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Bronwyn M Gunn
- The Ragon Institute of MIT, MGH and Harvard, Cambridge, MA, USA
| | - Jacob C Milligan
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, USA
| | - Galit Alter
- The Ragon Institute of MIT, MGH and Harvard, Cambridge, MA, USA.
| |
Collapse
|
23
|
Laabei M, Ermert D. Catch Me if You Can: Streptococcus pyogenes Complement Evasion Strategies. J Innate Immun 2018; 11:3-12. [PMID: 30269134 DOI: 10.1159/000492944] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 08/16/2018] [Indexed: 12/27/2022] Open
Abstract
The human host has evolved elaborate protection mechanisms to prevent infection from the billions of microorganisms to which it host is exposed and is home. One of these systems, complement, is an evolutionary ancient arm of innate immunity essential for combatting bacterial infection. Complement permits the efficient labelling of bacteria with opsonins, supports phagocytosis, and facilitates phagocyte recruitment to the site of infection through the production of chemoattractants. However, it is by no means perfect, and certain organisms engage in an evolutionary arms race with the host where complement has become a major target to promote immune evasion. Streptococcus pyogenes is a major human pathogen that causes significant morbidity and mortality globally. S. pyogenes is also a member of an elite group of bacterial pathogens possessing a sophisticated arsenal of virulence determinants capable of interfering with complement. In this review, we focus on these complement evasins, their mechanism of action, and their importance in disease progression. Finally, we highlight new therapeutic options for fighting S. pyogenes, by interfering with one of its main mechanisms of complement evasion.
Collapse
|
24
|
Kahler CM, Nawrocki KL, Anandan A, Vrielink A, Shafer WM. Structure-Function Relationships of the Neisserial EptA Enzyme Responsible for Phosphoethanolamine Decoration of Lipid A: Rationale for Drug Targeting. Front Microbiol 2018; 9:1922. [PMID: 30186254 PMCID: PMC6111236 DOI: 10.3389/fmicb.2018.01922] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 07/30/2018] [Indexed: 11/13/2022] Open
Abstract
Bacteria cause disease by two general mechanisms: the action of their toxins on host cells and induction of a pro-inflammatory response that can lead to a deleterious cytokine/chemokine response (e.g., the so-called cytokine storm) often seen in bacteremia/septicemia. These major mechanisms may overlap due to the action of surface structures that can have direct and indirect actions on phagocytic or non-phagocytic cells. In this respect, the lipid A (endotoxin) component of lipopolysaccharide (LPS) possessed by Gram-negative bacteria has been the subject of literally thousands of studies over the past century that clearly identified it as a key virulence factor in endotoxic shock. In addition to its capacity to modulate inflammatory responses, endotoxin can also modulate bacterial susceptibility to host antimicrobials, such as the host defense peptides termed cationic antimicrobial peptides. This review concentrates on the phosphoethanolamine (PEA) decoration of lipid A in the pathogenic species of the genus Neisseria [N. gonorrhoeae and N. meningitidis]. PEA decoration of lipid A is mediated by the enzyme EptA (formerly termed LptA) and promotes resistance to innate defense systems, induces the pro-inflammatory response and can influence the in vivo fitness of bacteria during infection. These important biological properties have driven efforts dealing with the biochemistry and structural biology of EptA that will facilitate the development of potential inhibitors that block PEA addition to lipid A.
Collapse
Affiliation(s)
- Charlene M Kahler
- The Marshall Center for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA, Australia.,Perth Children's Hospital, Telethon Kids Institute, Subiaco, WA, Australia
| | - K L Nawrocki
- Department of Microbiology and Immunology, The Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA, United States.,Laboratories of Bacterial Pathogenesis, VA Medical Center, Decatur, GA, United States
| | - A Anandan
- School of Molecular Sciences, University of Western Australia, Crawley, WA, Australia
| | - Alice Vrielink
- The Marshall Center for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA, Australia.,School of Molecular Sciences, University of Western Australia, Crawley, WA, Australia
| | - William M Shafer
- Department of Microbiology and Immunology, The Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA, United States.,Laboratories of Bacterial Pathogenesis, VA Medical Center, Decatur, GA, United States
| |
Collapse
|
25
|
Rice PA, Shafer WM, Ram S, Jerse AE. Neisseria gonorrhoeae: Drug Resistance, Mouse Models, and Vaccine Development. Annu Rev Microbiol 2018; 71:665-686. [PMID: 28886683 DOI: 10.1146/annurev-micro-090816-093530] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Gonorrhea, an obligate human infection, is on the rise worldwide and gonococcal strains resistant to many antibiotics are emerging. Appropriate antimicrobial treatment and prevention, including effective vaccines, are urgently needed. To guide investigation, an experimental model of genital tract infection has been developed in female mice to study mechanisms by which Neisseria gonorrhoeae evades host-derived antimicrobial factors and to identify protective and immunosuppressive pathways. Refinements of the animal model have also improved its use as a surrogate host of human infection and accelerated the testing of novel therapeutic and prophylactic compounds against gonococcal infection. Reviewed herein are the (a) history of antibiotic usage and resistance against gonorrhea and the consequences of resistance mechanisms that may increase gonococcal fitness and therefore the potential for spread, (b) use of gonococcal infection in the animal model system to study mechanisms of pathogenesis and host defenses, and
Collapse
Affiliation(s)
- Peter A Rice
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605-4321; ,
| | - William M Shafer
- Department of Microbiology and Immunology and Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, Georgia 30322.,Laboratories of Bacterial Pathogenesis, Veterans Affairs Medical Center, Decatur, Georgia 30033;
| | - Sanjay Ram
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605-4321; ,
| | - Ann E Jerse
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University, Bethesda, Maryland 20814-4799;
| |
Collapse
|
26
|
Blom AM, Magda M, Kohl L, Shaughnessy J, Lambris JD, Ram S, Ermert D. Factor H-IgG Chimeric Proteins as a Therapeutic Approach against the Gram-Positive Bacterial Pathogen Streptococcus pyogenes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2017; 199:3828-3839. [PMID: 29084837 PMCID: PMC5698128 DOI: 10.4049/jimmunol.1700426] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 09/30/2017] [Indexed: 11/19/2022]
Abstract
Bacteria can cause life-threatening infections, such as pneumonia, meningitis, or sepsis. Antibiotic therapy is a mainstay of treatment, although antimicrobial resistance has drastically increased over the years. Unfortunately, safe and effective vaccines against most pathogens have not yet been approved, and thus developing alternative treatments is important. We analyzed the efficiency of factor H (FH)6-7/Fc, a novel antibacterial immunotherapeutic protein against the Gram-positive bacterium Streptococcus pyogenes This protein is composed of two domains of complement inhibitor human FH (FH complement control protein modules 6 and 7) that bind to S. pyogenes, linked to the Fc region of IgG (FH6-7/Fc). FH6-7/Fc has previously been shown to enhance complement-dependent killing of, and facilitate bacterial clearance in, animal models of the Gram-negative pathogens Haemophilus influenzae and Neisseria meningitidis We hypothesized that activation of complement by FH6-7/Fc on the surface of Gram-positive bacteria such as S. pyogenes will enable professional phagocytes to eliminate the pathogen. We found that FH6-7/Fc alleviated S. pyogenes-induced sepsis in a transgenic mouse model expressing human FH (S. pyogenes binds FH in a human-specific manner). Furthermore, FH6-7/Fc, which binds to protein H and selected M proteins, displaced FH from the bacterial surface, enhanced alternative pathway activation, and reduced bacterial blood burden by opsonophagocytosis in a C3-dependent manner in an ex vivo human whole-blood model. In conclusion, FH-Fc chimeric proteins could serve as adjunctive treatments against multidrug-resistant bacterial infections.
Collapse
Affiliation(s)
- Anna M Blom
- Department of Translational Medicine, Medical Protein Chemistry, Lund University, Skåne County Council, Malmö 20502, Sweden
| | - Michal Magda
- Department of Translational Medicine, Medical Protein Chemistry, Lund University, Skåne County Council, Malmö 20502, Sweden
| | - Lisa Kohl
- Department of Translational Medicine, Medical Protein Chemistry, Lund University, Skåne County Council, Malmö 20502, Sweden
| | - Jutamas Shaughnessy
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605; and
| | - John D Lambris
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Sanjay Ram
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605; and
| | - David Ermert
- Department of Translational Medicine, Medical Protein Chemistry, Lund University, Skåne County Council, Malmö 20502, Sweden;
- Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01605; and
| |
Collapse
|
27
|
Ram S, Shaughnessy J, de Oliveira RB, Lewis LA, Gulati S, Rice PA. Gonococcal lipooligosaccharide sialylation: virulence factor and target for novel immunotherapeutics. Pathog Dis 2017; 75:3777971. [PMID: 28460033 PMCID: PMC5449626 DOI: 10.1093/femspd/ftx049] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2017] [Accepted: 04/26/2017] [Indexed: 12/13/2022] Open
Abstract
Gonorrhea has become resistant to most conventional antimicrobials used in clinical practice. The global spread of multidrug-resistant isolates of Neisseria gonorrhoeae could lead to an era of untreatable gonorrhea. New therapeutic modalities with novel mechanisms of action that do not lend themselves to the development of resistance are urgently needed. Gonococcal lipooligosaccharide (LOS) sialylation is critical for complement resistance and for establishing infection in humans and experimental mouse models. Here we describe two immunotherapeutic approaches that target LOS sialic acid: (i) a fusion protein that comprises the region in the complement inhibitor factor H (FH) that binds to sialylated gonococci and IgG Fc (FH/Fc fusion protein) and (ii) analogs of sialic acid that are incorporated into LOS but fail to protect the bacterium against killing. Both molecules showed efficacy in the mouse vaginal colonization model of gonorrhea and may represent promising immunotherapeutic approaches to target multidrug-resistant isolates. Disabling key gonococcal virulence mechanisms is an effective therapeutic strategy because the reduction of virulence is likely to be accompanied by a loss of fitness, rapid elimination by host immunity and consequently, decreased transmission.
Collapse
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. de Oliveira
- 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
| |
Collapse
|
28
|
Józsi M. Factor H Family Proteins in Complement Evasion of Microorganisms. Front Immunol 2017; 8:571. [PMID: 28572805 PMCID: PMC5435753 DOI: 10.3389/fimmu.2017.00571] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 04/28/2017] [Indexed: 01/08/2023] Open
Abstract
Human-pathogenic microbes possess various means to avoid destruction by our immune system. These include interactions with the host complement system that may facilitate pathogen entry into cells and tissues, expression of molecules that defuse the effector complement components and complexes, and acquisition of host complement inhibitors to downregulate complement activity on the surface of the pathogen. A growing number of pathogenic microorganisms have acquired the ability to bind the complement inhibitor factor H (FH) from body fluids and thus hijack its host protecting function. In addition to FH, binding of FH-related (FHR) proteins was also demonstrated for several microbes. Initial studies assumed that these proteins are complement inhibitors similar to FH. However, recent evidence suggests that FHR proteins may rather enhance complement activation both directly and also by competing with the inhibitor FH for binding to certain ligands and surfaces. This mini review focuses on the role of the main alternative pathway regulator FH in host–pathogen interactions, as well as on the emerging role of the FHR proteins as enhancers of complement activation.
Collapse
Affiliation(s)
- Mihály Józsi
- MTA-ELTE "Lendület" Complement Research Group, Department of Immunology, Eötvös Loránd University, Budapest, Hungary
| |
Collapse
|
29
|
Abstract
Simple and complex carbohydrates (glycans) have long been known to play major metabolic, structural and physical roles in biological systems. Targeted microbial binding to host glycans has also been studied for decades. But such biological roles can only explain some of the remarkable complexity and organismal diversity of glycans in nature. Reviewing the subject about two decades ago, one could find very few clear-cut instances of glycan-recognition-specific biological roles of glycans that were of intrinsic value to the organism expressing them. In striking contrast there is now a profusion of examples, such that this updated review cannot be comprehensive. Instead, a historical overview is presented, broad principles outlined and a few examples cited, representing diverse types of roles, mediated by various glycan classes, in different evolutionary lineages. What remains unchanged is the fact that while all theories regarding biological roles of glycans are supported by compelling evidence, exceptions to each can be found. In retrospect, this is not surprising. Complex and diverse glycans appear to be ubiquitous to all cells in nature, and essential to all life forms. Thus, >3 billion years of evolution consistently generated organisms that use these molecules for many key biological roles, even while sometimes coopting them for minor functions. In this respect, glycans are no different from other major macromolecular building blocks of life (nucleic acids, proteins and lipids), simply more rapidly evolving and complex. It is time for the diverse functional roles of glycans to be fully incorporated into the mainstream of biological sciences.
Collapse
Affiliation(s)
- Ajit Varki
- Departments of Medicine and Cellular & Molecular Medicine, Glycobiology Research and Training Center, University of California at San Diego, La Jolla, CA 92093-0687, USA
| |
Collapse
|
30
|
Ricklin D, Reis ES, Mastellos DC, Gros P, Lambris JD. Complement component C3 - The "Swiss Army Knife" of innate immunity and host defense. Immunol Rev 2016; 274:33-58. [PMID: 27782325 PMCID: PMC5427221 DOI: 10.1111/imr.12500] [Citation(s) in RCA: 273] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
As a preformed defense system, complement faces a delicate challenge in providing an immediate, forceful response to pathogens even at first encounter, while sparing host cells in the process. For this purpose, it engages a tightly regulated network of plasma proteins, cell surface receptors, and regulators. Complement component C3 plays a particularly versatile role in this process by keeping the cascade alert, acting as a point of convergence of activation pathways, fueling the amplification of the complement response, exerting direct effector functions, and helping to coordinate downstream immune responses. In recent years, it has become evident that nature engages the power of C3 not only to clear pathogens but also for a variety of homeostatic processes ranging from tissue regeneration and synapse pruning to clearing debris and controlling tumor cell progression. At the same time, its central position in immune surveillance makes C3 a target for microbial immune evasion and, if improperly engaged, a trigger point for various clinical conditions. In our review, we look at the versatile roles and evolutionary journey of C3, discuss new insights into the molecular basis for C3 function, provide examples of disease involvement, and summarize the emerging potential of C3 as a therapeutic target.
Collapse
Affiliation(s)
- Daniel Ricklin
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Edimara S Reis
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Dimitrios C Mastellos
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
- National Center for Scientific Research 'Demokritos', Athens, Greece
| | - Piet Gros
- Utrecht University, Utrecht, The Netherlands
| | - John D Lambris
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| |
Collapse
|