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Day CJ, Favuzza P, Bielfeld S, Haselhorst T, Seefeldt L, Hauser J, Shewell LK, Flueck C, Poole J, Jen FEC, Schäfer A, Dangy JP, Gilberger TW, França CT, Duraisingh MT, Tamborrini M, Brancucci NMB, Grüring C, Filarsky M, Jennings MP, Pluschke G. The essential malaria protein PfCyRPA targets glycans to invade erythrocytes. Cell Rep 2024; 43:114012. [PMID: 38573856 DOI: 10.1016/j.celrep.2024.114012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 12/15/2023] [Accepted: 03/13/2024] [Indexed: 04/06/2024] Open
Abstract
Plasmodium falciparum is a human-adapted apicomplexan parasite that causes the most dangerous form of malaria. P. falciparum cysteine-rich protective antigen (PfCyRPA) is an invasion complex protein essential for erythrocyte invasion. The precise role of PfCyRPA in this process has not been resolved. Here, we show that PfCyRPA is a lectin targeting glycans terminating with α2-6-linked N-acetylneuraminic acid (Neu5Ac). PfCyRPA has a >50-fold binding preference for human, α2-6-linked Neu5Ac over non-human, α2-6-linked N-glycolylneuraminic acid. PfCyRPA lectin sites were predicted by molecular modeling and validated by mutagenesis studies. Transgenic parasite lines expressing endogenous PfCyRPA with single amino acid exchange mutants indicated that the lectin activity of PfCyRPA has an important role in parasite invasion. Blocking PfCyRPA lectin activity with small molecules or with lectin-site-specific monoclonal antibodies can inhibit blood-stage parasite multiplication. Therefore, targeting PfCyRPA lectin activity with drugs, immunotherapy, or a vaccine-primed immune response is a promising strategy to prevent and treat malaria.
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Affiliation(s)
- Christopher J Day
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
| | - Paola Favuzza
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Sabrina Bielfeld
- Centre for Structural Systems Biology (CSSB), Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Thomas Haselhorst
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
| | - Leonie Seefeldt
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Julia Hauser
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Lucy K Shewell
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
| | - Christian Flueck
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Jessica Poole
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
| | - Freda E-C Jen
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
| | - Anja Schäfer
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Tim-W Gilberger
- Centre for Structural Systems Biology (CSSB), Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany; Department of Cellular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Camila Tenorio França
- Department of Immunology & Infectious Diseases, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Manoj T Duraisingh
- Department of Immunology & Infectious Diseases, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Marco Tamborrini
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Nicolas M B Brancucci
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Christof Grüring
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland
| | - Michael Filarsky
- Centre for Structural Systems Biology (CSSB), Hamburg, Germany; Department of Biology, University of Hamburg, Hamburg, Germany
| | - Michael P Jennings
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia.
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland; University of Basel, Basel, Switzerland.
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Pluschke G, Warryn L. How our molecular understanding of the pathogenesis of Mycobacterium ulcerans infection can improve diagnosis of Buruli ulcer. Expert Rev Mol Diagn 2024; 24:1-4. [PMID: 38073533 DOI: 10.1080/14737159.2023.2294333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 12/09/2023] [Indexed: 02/22/2024]
Affiliation(s)
- Gerd Pluschke
- Department of Medicine, Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Louisa Warryn
- Department of Medicine, Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
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Mäser P, Bernhard S, Brun R, Burri C, Gagneux S, Hetzel MW, Kaiser M, Lengeler C, Pluschke G, Reus E, Rottmann M, Utzinger J, Warryn L, Wittlin S, Keiser J. Key Contributions by the Swiss Tropical and Public Health Institute Towards New and Better Drugs for Tropical Diseases. Chimia (Aarau) 2023; 77:593-602. [PMID: 38047835 DOI: 10.2533/chimia.2023.593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 08/08/2023] [Indexed: 12/05/2023] Open
Abstract
Thanks to its expertise in clinical research, epidemiology, infectious diseases, microbiology, parasitology, public health, translational research and tropical medicine, coupled with deeply rooted partnerships with institutions in low- and middle-income countries (LMICs), the Swiss Tropical and Public Health Institute (Swiss TPH) has been a key contributor in many drug research and development consortia involving academia, pharma and product development partnerships. Our know-how of the maintenance of parasites and their life-cycles in the laboratory, plus our strong ties to research centres and disease control programme managers in LMICs with access to field sites and laboratories, have enabled systems for drug efficacy testing in vitro and in vivo, clinical research, and modelling to support the experimental approaches. Thus, Swiss TPH has made fundamental contributions towards the development of new drugs - and the better use of old drugs - for neglected tropical diseases and infectious diseases of poverty, such as Buruli ulcer, Chagas disease, food-borne trematodiasis (e.g. clonorchiasis, fascioliasis and opisthorchiasis), human African trypanosomiasis, leishmaniasis, malaria, schistosomiasis, soil-transmitted helminthiasis and tuberculosis. In this article, we show case the success stories of molecules to which Swiss TPH has made a substantial contribution regarding their use as anti-infective compounds with the ultimate aim to improve people's health and well-being.
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Affiliation(s)
- Pascal Mäser
- Dept. Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Sonja Bernhard
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Reto Brun
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Christian Burri
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Sébastien Gagneux
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Manuel W Hetzel
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Marcel Kaiser
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Christian Lengeler
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Elisabeth Reus
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Matthias Rottmann
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Louisa Warryn
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Sergio Wittlin
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
| | - Jennifer Keiser
- Swiss Tropical and Public Health Institute, CH-4123 Allschwil, Switzerland.
- University of Basel, CH-4001 Basel, Switzerland
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Warryn L, Pluschke G. Repurposing of Tuberculosis Drug Candidates for the Treatment of Mycobacterium ulcerans Disease. Chimia (Aarau) 2023; 77:577-581. [PMID: 38047833 DOI: 10.2533/chimia.2023.577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 12/05/2023] Open
Abstract
Buruli ulcer (BU) is a chronic necrotizing skin disease caused by Mycobacterium ulcerans. Historically, the disease was treated by surgical excision of the skin lesions, until an 8-week combination therapy of rifampicin and streptomycin was introduced in 2004. This treatment modality was effective and reduced recurrence rates. Rifampicin is the most efficacious antibiotic for the treatment of BU and, should rifampicin-resistant M. ulcerans strains emerge, there is currently no replacement for it. As for mycobacterial diseases in general, there is a pressing need for the development of novel, fast-acting drugs. Under market economy conditions, repurposing of new tuberculosis drug candidates is the most promising avenue for alternative BU treatments. Our drug repurposing activities have led to the identification of several actives against M. ulcerans. In particular, the cytochrome bc1 complex inhibitor telacebec (Q203) is a promising drug candidate for the treatment of BU in Africa and Australia. While an active cytochrome-bd oxidase bypass limits the potency of the cytochrome-bc1-specific inhibitor telacebec against M. tuberculosis, classical lineage M. ulcerans strains rely exclusively on cytochrome-bc1 to respire. Hence, telacebec is effective at nanomolar concentration against M. ulcerans, and a high treatment efficacy in an experimental mouse infection model indicates that treatment of BU could be substantially shortened and simplified by telacebec.
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Affiliation(s)
- Louisa Warryn
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, CH-4123 Allschwil, Switzerland.
- University of Basel, Basel, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, CH-4123 Allschwil, Switzerland.
- University of Basel, Basel, Switzerland
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Jen FEC, Abrahams JL, Schulz BL, Lamelas A, Pluschke G, Jennings MP. High-Frequency Changes in Pilin Glycosylation Patterns during Neisseria meningitidis Serogroup a Meningitis Outbreaks in the African Meningitis Belt. ACS Infect Dis 2023; 9:1451-1457. [PMID: 37467082 PMCID: PMC10425976 DOI: 10.1021/acsinfecdis.3c00149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Indexed: 07/21/2023]
Abstract
In the meningitis belt of sub-Saharan Africa, there are cyclic meningococcal epidemics that coincide with clonal waves of Neisseria meningitidis carriage and invasive disease. In the framework of longitudinal colonization and disease studies in Ghana and Burkina Faso, meningococcal isolates belonging to the closely related hypervirulent A:ST-5, A:ST-7, and A:ST-2859 clones have been collected from 1998 to 2011 during meningococcal outbreaks. A comparative whole-genome sequencing study with 100 of these isolates identified the pilin glycosylation (pgl) locus as one hot spot of recombination. Frequent exchange of pgl genes in N. meningitidis by lateral gene transfer results in differences in the glycosylation patterns of pilin and other cell surface glycoproteins. In this study, we looked at both recombination and phase variation of the pgl genes of these clinical isolates and analyzed the glycan structures resulting from different pgl alleles and their variable expression. Our results indicate that the basal O-linked sugar of the glycans expressed by these isolates is masked by various additional mono- or disaccharide structures whose expression is highly variable due to the phase-variable expression of pgl genes. We also observed a distinct glycoform in two isolates with pgl loci that were modified by recombination. These data suggest that variation in N. meningitidis protein glycosylation could be crucial for bacterial adaptation to evade herd immunity in semi-immune populations. Investigating pilin glycosylation in N. meningitidis can shed light on the mechanisms by which this pathogen evades the host immune response, and may help identify potential targets for novel therapies and vaccines.
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Affiliation(s)
- Freda E-C Jen
- Institute for Glycomics, Griffith University, Gold Coast, QLD 4222, Australia
| | - Jodie L Abrahams
- Institute for Glycomics, Griffith University, Gold Coast, QLD 4222, Australia
| | - Benjamin L Schulz
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Araceli Lamelas
- Swiss Tropical and Public Health Institute, Basel 4051, Switzerland
- University of Basel, Basel 4051, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel 4051, Switzerland
- University of Basel, Basel 4051, Switzerland
| | - Michael P Jennings
- Institute for Glycomics, Griffith University, Gold Coast, QLD 4222, Australia
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Tamborrini M, Schäfer A, Hauser J, Zou L, Paris DH, Pluschke G. The malaria blood stage antigen PfCyRPA formulated with the TLR-4 agonist adjuvant GLA-SE elicits parasite growth inhibitory antibodies in experimental animals. Malar J 2023; 22:210. [PMID: 37454145 DOI: 10.1186/s12936-023-04638-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 07/01/2023] [Indexed: 07/18/2023] Open
Abstract
BACKGROUND Plasmodium falciparum cysteine-rich protective antigen (PfCyRPA) is an invasion complex protein essential for erythrocyte invasion. In contrast to several previously clinically tested merozoite vaccine candidate antigens, PfCyRPA is not polymorphic, making it a promising candidate antigen for blood stage vaccine development. METHODS Mice and rabbits were immunized with vaccine formulations of recombinantly expressed PfCyRPA adjuvanted either with the glucopyranosyl lipid A (GLA) containing adjuvants GLA-LSQ, GLA-SE, GLA-Alum or with Nanoalum. ELISA and indirect immunofluorescence assays (IFA) were used to analyse elicited IgG titers and the P. falciparum growth inhibitory activity was determined with a standardized in vitro [3H]-hypoxanthine incorporation assay. RESULTS In the mouse experiments, the GLA adjuvanted formulations were superior to the Nanoalum formulation with respect to antibody titer development, IFA sero-conversion rates and in vitro parasite growth-inhibitory activity. In rabbits, the highest titers of parasite growth inhibitory antibodies were obtained with the GLA-SE formulation. Comparable mean ELISA IgG endpoint titers were reached in rabbits after three immunizations with GLA-SE adjuvanted PfCyRPA doses of 5, 25 and 100 µg, but with 100 µg of antigen, only two immunizations were required to reach this titer. CONCLUSION PfCyRPA formulated with the human-compatible adjuvant GLA-SE represents an attractive vaccine candidate for early clinical testing in a controlled P. falciparum blood stage challenge trial.
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Affiliation(s)
- Marco Tamborrini
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Anja Schäfer
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Julia Hauser
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Linghui Zou
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Daniel H Paris
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland.
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland.
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Ispasanie E, Muri L, Schmid M, Schubart A, Thorburn C, Zamurovic N, Holbro T, Kammüller M, Pluschke G. In vaccinated individuals serum bactericidal activity against B meningococci is abrogated by C5 inhibition but not by inhibition of the alternative complement pathway. Front Immunol 2023; 14:1180833. [PMID: 37457736 PMCID: PMC10349132 DOI: 10.3389/fimmu.2023.1180833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 06/05/2023] [Indexed: 07/18/2023] Open
Abstract
Introduction Several diseases caused by the dysregulation of complement activation can be treated with inhibitors of the complement components C5 and/or C3. However, complement is required for serum bactericidal activity (SBA) against encapsulated Gram-negative bacteria. Therefore, C3 and C5 inhibition increases the risk of invasive disease, in particular by Neisseria meningitidis. As inhibitors against complement components other than C3 and C5 may carry a reduced risk of infection, we compared the effect of inhibitors targeting the terminal pathway (C5), the central complement component C3, the alternative pathway (FB and FD), and the lectin pathway (MASP-2) on SBA against serogroup B meningococci. Methods Serum from adults was collected before and after vaccination with the meningococcal serogroup B vaccine 4CMenB and tested for meningococcal killing. Since the B capsular polysaccharide is structurally similar to certain human polysaccharides, 4CMenB was designed to elicit antibodies against meningococcal outer membrane proteins. Results While only a few pre-vaccination sera showed SBA against the tested B meningococcal isolates, 4CMenB vaccination induced potent complement-activating IgG titers against isolates expressing a matching allele of the bacterial cell surface-exposed factor H-binding protein (fHbp). SBA triggered by these cell surface protein-specific antibodies was blocked by C5 and reduced by C3 inhibition, whereas alternative (factor B and D) and lectin (MASP-2) pathway inhibitors had no effect on the SBA of post-4CMenB vaccination sera. Discussion Compared to the SBA triggered by A,C,W,Y capsule polysaccharide conjugate vaccination, SBA against B meningococci expressing a matching fHbp allele was remarkably resilient against the alternative pathway inhibition.
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Affiliation(s)
- Emma Ispasanie
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Lukas Muri
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Marc Schmid
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Anna Schubart
- Novartis Institutes for Biomedical Research, Department Autoimmunity, Transplantation and Inflammation, Basel, Switzerland
| | | | - Natasa Zamurovic
- Novartis Institutes for Biomedical Research, Translational Medicine-Preclinical Safety, Basel, Switzerland
| | - Thomas Holbro
- Global Drug Development, Novartis Pharma AG, Basel, Switzerland
| | - Michael Kammüller
- Novartis Institutes for Biomedical Research, Translational Medicine-Preclinical Safety, Basel, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
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Leuenberger A, Koné BV, N’krumah RTAS, Koffi DY, Bonfoh B, Utzinger J, Pluschke G. Perceived water-related risk factors of Buruli ulcer in two villages of south-central Côte d'Ivoire. PLoS Negl Trop Dis 2022; 16:e0010927. [PMID: 36516125 PMCID: PMC9750022 DOI: 10.1371/journal.pntd.0010927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 11/01/2022] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Buruli ulcer, caused by Mycobacterium ulcerans, is a neglected tropical skin disease that is primarily endemic in West and Central Africa, including Côte d'Ivoire. Studies indicate that M. ulcerans infections are caused by contact with an environmental reservoir of the bacteria, governed by specific human biological conditions. Yet, the nature of this reservoir and the exact mode of transmission remain unknown. METHODOLOGY To identify ecologic risk factors of Buruli ulcer in south-central Côte d'Ivoire, we pursued a qualitative study matched with geo-referencing inquiry. Embedded in a broader integrated wound management research project, we (i) mapped households and water sources of laboratory confirmed Buruli ulcer cases and (ii) interviewed 12 patients and four health care workers to assess exposure to surface water and to deepen the understanding of perceived transmission pathways. PRINCIPAL FINDINGS Water availability, accessibility, and affordability were reported as key determinants for choosing water resources. Furthermore, perceived risks were related to environmental, structural, and individual factors. Despite the presence of improved water sources (e.g., drilled wells), communities heavily relied on unprotected surface water for a multitude of activities. The nearby Bandama River and seasonal waterbodies were frequently used for washing, bathing, and collection of water for drinking and cooking. Many residents also reported to cross the river on a daily basis for agricultural chores, and hence, are exposed to stagnant water during farming activities. CONCLUSIONS/SIGNIFICANCE Our study in two Buruli ulcer endemic villages in south-central Côte d'Ivoire revealed a wide range of water-related domestic activities that might expose people to an increased risk of contracting the disease. Environmental, biological, social, and cultural risk factors are closely interlinked and should be considered in future investigations of Buruli ulcer transmission. Active participation of the communities is key to better understand their circumstances to advance research and fight against Buruli ulcer and other neglected tropical diseases.
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Affiliation(s)
- Andrea Leuenberger
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail:
| | - Bognan V. Koné
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Raymond T. A. S. N’krumah
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Université Peleforo Gon Coulibaly de Korhogo, Korhogo, Côte d’Ivoire
| | - Didier Y. Koffi
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Programme National de Lutte contre l’Ulcère de Buruli, Abidjan, Côte d’Ivoire
| | - Bassirou Bonfoh
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Jürg Utzinger
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland
- University of Basel, Basel, Switzerland
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Muri L, Schubart A, Thorburn C, Zamurovic N, Holbro T, Kammüller M, Pluschke G, Ispasanie E. Inhibition of the different complement pathways has varying impacts on the serum bactericidal activity and opsonophagocytosis against Haemophilus influenzae type b. Front Immunol 2022; 13:1020580. [PMID: 36578495 PMCID: PMC9791579 DOI: 10.3389/fimmu.2022.1020580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 10/25/2022] [Indexed: 12/14/2022] Open
Abstract
Defense against Haemophilus influenzae type b (Hib) is dependent on antibodies and complement, which mediate both serum bactericidal activity (SBA) and opsonophagocytosis. Here we evaluated the influence of capsule-specific antibodies and complement inhibitors targeting the central component C3, the alternative pathway (AP; fB, fD), the lectin pathway (LP; MASP-2) and the terminal pathway (C5) on both effector functions. Findings may be relevant for the treatment of certain diseases caused by dysregulation of the complement system, where inhibitors of complement factors C3 or C5 are used. Inhibitors against other complement components are being evaluated as potential alternative treatment options that may carry a reduced risk of infection by encapsulated bacteria. Serum and reconstituted blood of healthy adults were tested for bactericidal activity before and after vaccination with the Hib capsule-conjugate vaccine ActHIB. Most sera had bactericidal activity prior to vaccination, but vaccination significantly enhanced SBA titers. Independently of the vaccination status, both C3 and C5 inhibition abrogated SBA, whereas inhibition of the LP had no effect. AP inhibition had a major inhibitory effect on SBA of pre- vaccination serum, but vaccination mitigated this inhibition for all disease isolates tested. Despite this, SBA-mediated killing of some Hib isolates remained retarded. Even for the most serum-resistant isolate, SBA was the dominating defense mechanism in reconstituted whole blood, as addition of blood cells to the serum did not enhance bacterial killing. Limited Fc receptor-mediated opsonophagocytosis was unmasked when bacterial killing by the membrane attack complex was blocked. In the presence of C3 or C5 inhibitors, addition of post-vaccination, but not of pre-vaccination serum to the blood cells triggered opsonophagocytosis, leading to suppression of bacterial multiplication. Taken together, our data indicate that for host defense against Hib, killing by SBA is more efficient than by blood cell opsonophagocytosis. However, additional defense mechanisms, such as bacterial clearance by spleen and liver, may play an important role in preventing Hib-mediated sepsis, in particular for Hib isolates with increased serum-resistance. Results indicate potentially improved safety profile of AP inhibitors over C3 and C5 inhibitors as alternative therapeutic agents in patients with increased susceptibility to Hib infection.
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Affiliation(s)
- Lukas Muri
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland,University of Basel, Basel, Switzerland
| | - Anna Schubart
- Department Autoimmunity, Transplantation and Inflammation, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | | | - Natasa Zamurovic
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Thomas Holbro
- Global Drug Development, Novartis Pharma AG, Basel, Switzerland
| | - Michael Kammüller
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Gerd Pluschke
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland,University of Basel, Basel, Switzerland,*Correspondence: Gerd Pluschke,
| | - Emma Ispasanie
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland,University of Basel, Basel, Switzerland
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10
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Toppino S, Koffi DY, Kone BV, N’Krumah RTAS, Coulibaly ID, Tobian F, Pluschke G, Stojkovic M, Bonfoh B, Junghanss T. Community-based wound management in a rural setting of Côte d'Ivoire. PLoS Negl Trop Dis 2022; 16:e0010730. [PMID: 36227844 PMCID: PMC9560516 DOI: 10.1371/journal.pntd.0010730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 08/10/2022] [Indexed: 11/05/2022] Open
Abstract
Background Wounds are a neglected health problem in rural communities of low-income countries, mostly caused by trauma and ulcerative skin diseases including Neglected Tropical Diseases (NTDs) and associated with systemic complications and disability. Rural communities have limited access to high quality health services-based wound care. Methods We conducted a prospective observational study on wound management at three levels–community (C), health centre (HC), district hospital (DH)—in a rural community of Côte d’Ivoire. Patients with skin wounds actively identified in a house-to-house survey and passively in the health services in a defined area of the Taabo Health and Demographic Surveillance System were asked to participate and followed-up longitudinally. Endpoints were proportion of wounds closed, time to wound closure, wound size over time, frequency of secondary bacterial infection, need for recapturing after follow-up interruption, and duration of treatment stratified by health service level and wound aetiology. Results We enrolled 561 patients with 923 wounds between May 2019 and March 2020. The observation period ended in March 2021. Median age was 10 years (IQR 7–15), 63.0% of patients were male. Almost all (99.5%, 870/874) wounds closed within the observation period, 5.3% (49/923) were lost to follow-up. Wounds primarily treated in C, HC and DH closed within a median time of 10, 16 and 170 days, respectively. Median time to acute wound and chronic wound closure was 13 and 72 days, respectively. Wounds treated in C, HC and DH presented with secondary bacterial infections in 10.3% (36/350), 31.0% (133/429) and 100% (5/5) of cases, respectively. Recapturing was required in 68.3% (630/923) of wounds with participants reporting wound closure as the main reason for not attending follow-up. Conclusions We describe a wound management model based on national and WHO recommendations focusing on early identification and treatment in the community with potential for broad implementation in low-income countries. Trial registration Registration at ClinicalTrials.gov (NCT03957447). Wounds are a neglected health problem in rural communities of low-income countries, mostly caused by trauma and ulcerative skin diseases including Neglected Tropical Diseases (NTDs) and associated with systemic complications and disability. Rural communities have limited access to high quality health services-based wound care. We conducted a prospective observational study on WHO recommendation-based wound management at three levels–community, health centre, district hospital—in a rural community of Côte d’Ivoire. The healthcare personnel were trained in wound identification and treatment. Patients with skin wounds of all causes identified actively in a house-to-house survey and passively in the health services in a defined area of a Health and Demographic Surveillance System were included in the study and followed-up longitudinally. Most wounds could be treated with basic wound care in the community or at the health centre by local healthcare personnel and closed within 2 to 3 weeks. Few wounds required referral to the district hospital or specific treatment. The results of our study indicate that a community-centred wound management model based on WHO recommendations and focusing on early identification and treatment of all wounds independent of the cause has potential for broad implementation in low-income countries.
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Affiliation(s)
- Simone Toppino
- Division Infectious Diseases and Tropical Medicine, Heidelberg University Hospital, Heidelberg, Germany
- * E-mail:
| | - Didier Yao Koffi
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Programme National de Lutte contre l’Ulcère de Buruli, Abidjan, Côte d’Ivoire
- Université Félix Houphouët-Boigny d’Abidjan, Abidjan, Côte d’Ivoire
| | - Bognan Valentin Kone
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Raymond T. A. S. N’Krumah
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Université Peleforo Gon Coulibaly de Korhogo, Korhogo, Côte d’Ivoire
| | - Ismaël Dognimin Coulibaly
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
- Université Peleforo Gon Coulibaly de Korhogo, Korhogo, Côte d’Ivoire
| | - Frank Tobian
- Division Infectious Diseases and Tropical Medicine, Heidelberg University Hospital, Heidelberg, Germany
| | - Gerd Pluschke
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Marija Stojkovic
- Division Infectious Diseases and Tropical Medicine, Heidelberg University Hospital, Heidelberg, Germany
| | - Bassirou Bonfoh
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire
| | - Thomas Junghanss
- Division Infectious Diseases and Tropical Medicine, Heidelberg University Hospital, Heidelberg, Germany
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11
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Fernandes B, Sousa M, Castro R, Schäfer A, Hauser J, Schulze K, Amacker M, Tamborrini M, Pluschke G, Alves PM, Fleury S, Roldão A. Scalable Process for High-Yield Production of PfCyRPA Using Insect Cells for Inclusion in a Malaria Virosome-Based Vaccine Candidate. Front Bioeng Biotechnol 2022; 10:879078. [PMID: 35669054 PMCID: PMC9163744 DOI: 10.3389/fbioe.2022.879078] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 04/05/2022] [Indexed: 11/13/2022] Open
Abstract
Plasmodium falciparum cysteine-rich protective antigen (PfCyRPA) has been identified as a promising blood-stage candidate antigen to include in a broadly cross-reactive malaria vaccine. In the last couple of decades, substantial effort has been committed to the development of scalable cost-effective, robust, and high-yield PfCyRPA production processes. Despite insect cells being a suitable expression system due to their track record for protein production (including vaccine antigens), these are yet to be explored to produce this antigen. In this study, different insect cell lines, culture conditions (baculovirus infection strategy, supplementation schemes, culture temperature modulation), and purification strategies (affinity tags) were explored aiming to develop a scalable, high-yield, and high-quality PfCyRPA for inclusion in a virosome-based malaria vaccine candidate. Supplements with antioxidants improved PfCyRPA volumetric titers by 50% when added at the time of infection. In addition, from three different affinity tags (6x-His, 4x-His, and C-tag) evaluated, the 4x-His affinity tag was the one leading to the highest PfCyRPA purification recovery yields (61%) and production yield (26 mg/L vs. 21 mg/L and 13 mg/L for 6x-His and C-tag, respectively). Noteworthy, PfCyRPA expressed using High Five cells did not show differences in protein quality or stability when compared to its human HEK293 cell counterpart. When formulated in a lipid-based virosome nanoparticle, immunized rabbits developed functional anti-PfCyRPA antibodies that impeded the multiplication of P. falciparum in vitro. This work demonstrates the potential of using IC-BEVS as a qualified platform to produce functional recombinant PfCyRPA protein with the added benefit of being a non-human expression system with short bioprocessing times and high expression levels.
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Affiliation(s)
- Bárbara Fernandes
- iBET-Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal
- ITQB NOVA-Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Marcos Sousa
- iBET-Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal
- ITQB NOVA-Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | - Rute Castro
- iBET-Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal
| | - Anja Schäfer
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Julia Hauser
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Kai Schulze
- Helmhotz Center for Infecion Research, Braunschweig, Germany
| | - Mario Amacker
- Mymetics SA, Épalinges, Switzerland
- Department of Pulmonary Medicine, Bern University Hospital, University of Bern, Bern, Switzerland
| | - Marco Tamborrini
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Paula M Alves
- iBET-Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal
- ITQB NOVA-Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
| | | | - António Roldão
- iBET-Instituto de Biologia Experimental e Tecnológica, Oeiras, Portugal
- ITQB NOVA-Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal
- *Correspondence: António Roldão,
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12
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Pluschke G, Röltgen K. Overview: Development of Drugs Against Mycobacterium ulcerans. Methods Mol Biol 2022; 2387:185-187. [PMID: 34643912 DOI: 10.1007/978-1-0716-1779-3_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023]
Abstract
For many years, wide margin surgical excision of Buruli ulcer lesions has been the main approach for the treatment of Mycobacterium ulcerans disease. The WHO now recommends an eight-week course of oral antibiotics with a combination of rifampicin and clarithromycin in Africa. However, disease management is complicated by social stigma, lack of awareness, and limited access to healthcare facilities, resulting in underreporting and frequently late initiation of medical treatment. Inadequate initial treatment can drive permanent disabilities and also limited compliance to the eight-week therapy is a limitation. Therefore, search for a faster and more simple treatment modality is ongoing, focusing primarily on the testing of new tuberculosis drug candidates for the treatment of M. ulcerans disease.
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Affiliation(s)
- Gerd Pluschke
- Molecular Immunology, Swiss Tropical and Public Health Institute, Basel, Switzerland.
- University of Basel, Basel, Switzerland.
| | - Katharina Röltgen
- Molecular Immunology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- Department of Pathology, Stanford School of Medicine, Stanford University, Stanford, CA, USA
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13
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Muri L, Ispasanie E, Schubart A, Thorburn C, Zamurovic N, Holbro T, Kammüller M, Pluschke G. Alternative Complement Pathway Inhibition Abrogates Pneumococcal Opsonophagocytosis in Vaccine-Naïve, but Not in Vaccinated Individuals. Front Immunol 2021; 12:732146. [PMID: 34707606 PMCID: PMC8543009 DOI: 10.3389/fimmu.2021.732146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 09/23/2021] [Indexed: 01/19/2023] Open
Abstract
To assess the relative contribution of opsonisation by antibodies, classical and alternative complement pathways to pneumococcal phagocytosis, we analyzed killing of pneumococci by human blood leukocytes collected from vaccine-naïve and PCV13-vaccinated subjects. With serotype 4 pneumococci as model, two different physiologic opsonophagocytosis assays based on either hirudin-anticoagulated whole blood or on washed cells from EDTA-anticoagulated blood reconstituted with active serum, were compared. Pneumococcal killing was measured in the presence of inhibitors targeting the complement components C3, C5, MASP-2, factor B or factor D. The two assay formats yielded highly consistent and comparable results. They highlighted the importance of alternative complement pathway activation for efficient opsonophagocytic killing in blood of vaccine-naïve subjects. In contrast, alternative complement pathway inhibition did not affect pneumococcal killing in PCV13-vaccinated individuals. Independent of amplification by the alternative pathway, even low capsule-specific antibody concentrations were sufficient to efficiently trigger classical pathway mediated opsonophagocytosis. In heat-inactivated or C3-inhibited serum, high concentrations of capsule-specific antibodies were required to trigger complement-independent opsonophagocytosis. Our findings suggest that treatment with alternative complement pathway inhibitors will increase susceptibility for invasive pneumococcal infection in non-immune subjects, but it will not impede pneumococcal clearance in vaccinated individuals.
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Affiliation(s)
- Lukas Muri
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Emma Ispasanie
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Anna Schubart
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | | | - Natasa Zamurovic
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Thomas Holbro
- Novartis Pharma AG, Global Drug Development, Basel, Switzerland
| | - Michael Kammüller
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Gerd Pluschke
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
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14
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Ispasanie E, Muri L, Schubart A, Thorburn C, Zamurovic N, Holbro T, Kammüller M, Pluschke G. Alternative Complement Pathway Inhibition Does Not Abrogate Meningococcal Killing by Serum of Vaccinated Individuals. Front Immunol 2021; 12:747594. [PMID: 34691058 PMCID: PMC8531814 DOI: 10.3389/fimmu.2021.747594] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 09/21/2021] [Indexed: 11/13/2022] Open
Abstract
Dysregulation of complement activation causes a number of diseases, including paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome. These conditions can be treated with monoclonal antibodies (mAbs) that bind to the complement component C5 and prevent formation of the membrane attack complex (MAC). While MAC is involved in uncontrolled lysis of erythrocytes in these patients, it is also required for serum bactericidal activity (SBA), i.e. clearance of encapsulated bacteria. Therefore, terminal complement blockage in these patients increases the risk of invasive disease by Neisseria meningitidis more than 1000-fold compared to the general population, despite obligatory vaccination. It is assumed that alternative instead of terminal pathway inhibition reduces the risk of meningococcal disease in vaccinated individuals. To address this, we investigated the SBA with alternative pathway inhibitors. Serum was collected from adults before and after vaccination with a meningococcal serogroup A, C, W, Y capsule conjugate vaccine and tested for meningococcal killing in the presence of factor B and D, C3, C5 and MASP-2 inhibitors. B meningococci were not included in this study since the immune response against protein-based vaccines is more complex. Unsurprisingly, inhibition of C5 abrogated killing of meningococci by all sera. In contrast, both factor B and D inhibitors affected meningococcal killing in sera from individuals with low, but not with high bactericidal anti-capsular titers. While the anti-MASP-2 mAb did not impair SBA, inhibition of C3 impeded meningococcal killing in most, but not in all sera. These data provide evidence that vaccination can provide protection against invasive meningococcal disease in patients treated with alternative pathway inhibitors.
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Affiliation(s)
- Emma Ispasanie
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Lukas Muri
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Anna Schubart
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | | | - Natasa Zamurovic
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Thomas Holbro
- Global Drug Development, Novartis Pharma AG, Basel, Switzerland
| | - Michael Kammüller
- Translational Medicine-Preclinical Safety, Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Gerd Pluschke
- Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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15
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Hall BS, Dos Santos SJ, Hsieh LTH, Manifava M, Ruf MT, Pluschke G, Ktistakis N, Simmonds RE. Inhibition of the SEC61 translocon by mycolactone induces a protective autophagic response controlled by EIF2S1-dependent translation that does not require ULK1 activity. Autophagy 2021; 18:841-859. [PMID: 34424124 PMCID: PMC9037441 DOI: 10.1080/15548627.2021.1961067] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The Mycobacterium ulcerans exotoxin, mycolactone, is responsible for the immunosuppression and tissue necrosis that characterizes Buruli ulcer. Mycolactone inhibits SEC61-dependent co-translational translocation of proteins into the endoplasmic reticulum and the resultant cytosolic translation triggers degradation of mislocalized proteins by the ubiquitin-proteasome system. Inhibition of SEC61 by mycolactone also activates multiple EIF2S1/eIF2α kinases in the integrated stress response (ISR). Here we show mycolactone increased canonical markers of selective macroautophagy/autophagy LC3B-II, ubiquitin and SQSTM1/p62 in diverse disease-relevant primary cells and cell lines. Increased formation of puncta positive for the early autophagy markers WIPI2, RB1CC1/FIP200 and ATG16L1 indicates increased initiation of autophagy. The mycolactone response was SEC61A1-dependent and involved a pathway that required RB1CC1 but not ULK. Deletion of Sqstm1 reduced cell survival in the presence of mycolactone, suggesting this response protects against the increased cytosolic protein burden caused by the toxin. However, reconstitution of baseline SQSTM1 expression in cells lacking all autophagy receptor proteins could not rescue viability. Translational regulation by EIF2S1 in the ISR plays a key role in the autophagic response to mycolactone. Mycolactone-dependent induction of SQSTM1 was reduced in eif2ak3−/-/perk−/- cells while the p-EIF2S1 antagonist ISRIB reversed the upregulation of SQSTM1 and reduced RB1CC1, WIPI2 and LC3B puncta formation. Increased SQSTM1 staining could be seen in Buruli ulcer patient skin biopsy samples, reinforcing genetic data that suggests autophagy is relevant to disease pathology. Since selective autophagy and the ISR are both implicated in neurodegeneration, cancer and inflammation, the pathway uncovered here may have a broad relevance to human disease. Abbreviations: ATF4: activating transcription factor 4; ATG: autophagy related; BAF: bafilomycin A1; ATG16L1: autophagy related 16 like 1; BU: Buruli ulcer; CQ: chloroquine; EIF2AK3: eukaryotic translation initiation factor 2 alpha kinase 3; CALCOCO2: calcium binding and coiled-coil domain 2; DMSO: dimethyl sulfoxide; EIF2S1: eukaryotic translation initiation factor 2 subunit alpha; ER: endoplasmic reticulum; GFP: green fluorescent protein; HDMEC: human dermal microvascular endothelial cells; HFFF: human fetal foreskin fibroblasts; ISR: integrated stress response; ISRIB: integrated stress response inhibitor; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MEF: mouse embryonic fibroblast; Myco: mycolactone; NBR1: NBR1 autophagy cargo receptor; NFE2L2: nuclear factor, erythroid 2 like 2; OPTN: optineurin; PFA: paraformaldehyde; PtdIns3P: phosphatidylinositol-3-phosphate; RB1CC1: RB1-inducible coiled coil 1; SQSTM1: sequestosome 1; TAX1BP1: Tax1 binding protein 1; ULK: unc-51 like autophagy activating kinase; UPS: ubiquitin-proteasome system; WIPI: WD repeat domain, phosphoinositide interacting; WT: wild type.
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Affiliation(s)
- Belinda S Hall
- Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, UK
| | - Scott J Dos Santos
- Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, UK
| | - Louise Tzung-Harn Hsieh
- Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, UK
| | | | - Marie-Thérèse Ruf
- Molecular Immunology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,Medical Parasitology and Infection Biology Department, University of Basel, Basel, Switzerland
| | - Gerd Pluschke
- Molecular Immunology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,Medical Parasitology and Infection Biology Department, University of Basel, Basel, Switzerland
| | | | - Rachel E Simmonds
- Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, UK
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16
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Warryn L, Dangy JP, Gersbach P, Gehringer M, Altmann KH, Pluschke G. An Antigen Capture Assay for the Detection of Mycolactone, the Polyketide Toxin of Mycobacterium ulcerans. J Immunol 2021; 206:2753-2762. [PMID: 34031146 DOI: 10.4049/jimmunol.2001232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/29/2021] [Indexed: 11/19/2022]
Abstract
Mycolactone is a cytotoxin responsible for most of the chronic necrotizing pathology of Mycobacterium ulcerans disease (Buruli ulcer). The polyketide toxin consists of a 12-membered lactone ring with a lower O-linked polyunsaturated acyl side chain and an upper C-linked side chain. Mycolactone is unique to M. ulcerans and an immunological Ag capture assay would represent an important tool for the study of Buruli ulcer pathogenesis and for laboratory diagnosis. When testing sets of mycolactone-specific mouse mAbs, we found that Abs against the hydrophobic lower side chain only bind mycolactone immobilized on a solid support but not when present in solution. This observation supports previous findings that mycolactone forms micellar structures in aqueous solution with the hydrophobic region sequestered into the inner core of the aggregates. Although an Ag capture assay typically requires two Abs that recognize nonoverlapping epitopes, our search for matching pairs of mAbs showed that the same mAb could be used both as capture and as detecting reagent for the detection of the mycolactone aggregates. However, the combination of a core-specific and a core/upper side chain-specific mAb constituted the most sensitive ELISA with a sensitivity in the low nanogram range. The results of a pilot experiment showed that the sensitivity of the assay is sufficient to detect mycolactone in swab samples from Buruli ulcer lesions. Although the described capture ELISA can serve as a tool for research on the biology of mycolactone, the assay system will have to be adapted for use as a diagnostic tool.
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Affiliation(s)
- Louisa Warryn
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland; and
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland; and
| | - Philipp Gersbach
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zürich, Zürich, Switzerland
| | - Matthias Gehringer
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zürich, Zürich, Switzerland
| | - Karl-Heinz Altmann
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology Zürich, Zürich, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland; .,University of Basel, Basel, Switzerland; and
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17
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Day CJ, Röltgen K, Pluschke G, Jennings MP. The cell surface protein MUL_3720 confers binding of the skin pathogen Mycobacterium ulcerans to sulfated glycans and keratin. PLoS Negl Trop Dis 2021; 15:e0009136. [PMID: 33630844 PMCID: PMC7906334 DOI: 10.1371/journal.pntd.0009136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 01/13/2021] [Indexed: 11/19/2022] Open
Abstract
Mycobacterium ulcerans is the causative agent of the chronic, necrotizing skin disease Buruli ulcer. Modes of transmission and molecular mechanisms involved in the establishment of M. ulcerans infections are poorly understood. Interactions with host glycans are often crucial in bacterial pathogenesis and the 22 kDa M. ulcerans protein MUL_3720 has a putative role in host cell attachment. It has a predicted N-terminal lectin domain and a C-terminal peptidoglycan-binding domain and is highly expressed on the surface of the bacilli. Here we report the glycan-binding repertoire of whole, fixed M. ulcerans bacteria and of purified, recombinant MUL_3720. On an array comprising 368 diverse biologically relevant glycan structures, M. ulcerans cells showed binding to 64 glycan structures, representing several distinct classes of glycans, including sulfated structures. MUL_3720 bound only to glycans containing sulfated galactose and GalNAc, such as glycans known to be associated with keratins isolated from human skin. Surface plasmon resonance studies demonstrated that both whole, fixed M. ulcerans cells and MUL_3720 show high affinity interactions with both glycans and human skin keratin extracts. This MUL_3720-mediated interaction with glycans associated with human skin keratin may contribute to the pathobiology of Buruli ulcer. Mycobacterium ulcerans causes a skin-based disease known as Buruli ulcer. How the bacteria are transmitted and what mechanisms they use to establish the infection of the skin is poorly understood. The only well characterized bacterial factor in Buruli ulcer pathogenesis is mycolactone, a toxin produced by the bacteria. Mycolactone causes apoptosis in human cells, leading to destruction of the skin around extracellular clusters of the mycobacteria. Human cells, like cells of all orders of life, are coated in complex sugar structures and these glycans are one of the major targets of bacteria and viruses for the interaction with host cells. Here we describe the glycan binding of whole Mycobacterium ulcerans cells and a mycobacterial protein, MUL_3720, thought to be involved in glycan binding. We show that both the bacterial cells and MUL_3720 bind to glycans known to be associated with human skin keratin and to skin keratin extracts. This binding of keratin extracts may explain initial bacterial attachment and clustering of the bacteria in the skin, ultimately leading to tissue destruction and ulceration caused by a cloud of secreted mycolactone at the site of infection.
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Affiliation(s)
- Christopher J. Day
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Katharina Röltgen
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- * E-mail: (GP); (MPJ)
| | - Michael P. Jennings
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
- * E-mail: (GP); (MPJ)
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18
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Brunetti G, Padovani F, De Pastina A, Rotella C, Monahan A, Hoffman SL, Jongo SA, Abdulla S, Corradin G, Pluschke G, Daubenberger C, Hegner M. Nanotechnological immunoassay for rapid label-free analysis of candidate malaria vaccines. Nanoscale 2021; 13:2338-2349. [PMID: 33438712 DOI: 10.1039/d0nr08083g] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Malaria is a life-threatening epidemic disease with half of the world's population at risk. Although its incidence rate has fallen since 2010, this ratio dramatically stalled between 2014 and 2018. New fast and optimized tools in vaccine analysis and seroconversion testing are critically needed. We developed a clinical diagnostic device based on piezo-actuated nanoresonators that perform as quantitative in situ calibrated nano-bio sensors for specific detection of multiple target molecules in serum samples. The immunoassay successfully diagnoses humoral immune responses induced by malaria vaccine candidates and reveals the timeline and stage of the infection. We applied the newly developed strategy to a variety of different samples, from pure antibody/vaccine solutions, to blood samples from clinical trials on both naïve and pre-exposed malaria volunteers from sub-Saharan countries. Our nanomechanical assay provides a direct one-step label-free quantitative immunoassay that is on par with the gold-standard, multi-step enzyme-linked immunosorbent assay (ELISA). We achieve a limit of detection of few pg ml-1, or sub-pM concentrations. The 6 μl sample volume allows more than 50 experiments from one finger prick. Furthermore, we simultaneously detected multiple analytes by differential functionalization of multiple sensors in parallel. The inherent differential read-out with in situ controls reduces false positive results. Due to the faster turnaround time, the minimal volume required and the automatized handling system, this technique has great potential for miniaturization and routine diagnostics in pandemic emergencies.
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Affiliation(s)
- Giulio Brunetti
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), School of Physics, Trinity College Dublin, Dublin, Ireland.
| | - Francesco Padovani
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), School of Physics, Trinity College Dublin, Dublin, Ireland. and Institute of Functional Epigenetics, Helmholtz Zentrum München (HMGU), Neuherberg 85764, Germany
| | - Annalisa De Pastina
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), School of Physics, Trinity College Dublin, Dublin, Ireland.
| | - Chiara Rotella
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), School of Physics, Trinity College Dublin, Dublin, Ireland.
| | - Amy Monahan
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), School of Physics, Trinity College Dublin, Dublin, Ireland.
| | | | - Said A Jongo
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, Tanzania
| | - Salim Abdulla
- Bagamoyo Research and Training Centre, Ifakara Health Institute, Bagamoyo, Tanzania
| | | | - Gerd Pluschke
- Medical Parasitology and Infection Biology Department, Molecular Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland and University of Basel, Switzerland
| | - Claudia Daubenberger
- University of Basel, Switzerland and Medical Parasitology and Infection Biology Department, Clinical Immunology Unit, Swiss Tropical and Public Health Institute, Basel, Switzerland.
| | - Martin Hegner
- Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), School of Physics, Trinity College Dublin, Dublin, Ireland.
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19
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Borel N, Sauer-Durand AM, Hartel M, Kuratli J, Vaupel P, Scherr N, Pluschke G. wIRA: hyperthermia as a treatment option for intracellular bacteria, with special focus on Chlamydiae and Mycobacteria. Int J Hyperthermia 2020; 37:373-383. [PMID: 32319834 DOI: 10.1080/02656736.2020.1751312] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The emergence of antibiotic-resistant bacteria in the last century is alarming and calls for alternative, nonchemical treatment strategies. Thermal medicine uses heat for the treatment of infectious diseases but its use in facultative and obligate intracellular bacteria remains poorly studied. In this review, we summarize previous research on reducing the infectious burden of Mycobacterium ulcerans and Chlamydia trachomatis by using water-filtered infrared A-radiation (wIRA), a special form of heat radiation with high tissue penetration and low thermal load on the skin surface. Mycobacterium ulcerans is a thermosensitive bacterium causing chronic necrotizing skin disease. Therefore, previous data on wIRA-induced improvement of wound healing and reduction of wound infections is summarized first. Then, pathogenesis and treatment of infections with M. ulcerans causing Buruli ulcer and of those with C. trachomatis infecting the ocular conjunctiva and resulting in blinding trachoma are discussed. Both bacteria cause neglected tropical diseases and have similar geographical distributions. Results of previous in vitro and in vivo studies using wIRA on M. ulcerans and C. trachomatis infections are presented. Finally, technical aspects of using wIRA in patients are critically reviewed and open questions driving future research are highlighted. In conclusion, wIRA is a promising tool for reducing infectious burden due to intracellular bacteria such as M. ulcerans and C. trachomatis.
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Affiliation(s)
- Nicole Borel
- Infection Pathology Unit, Department of Pathobiology, Vetsuisse Faculty and Center for Applied Biotechnology and Molecular Medicine (CABMM), Institute of Veterinary Pathology, University of Zurich, Zurich, Switzerland
| | | | - Mark Hartel
- Clinic for Visceral Surgery, Cantonal Hospital Aarau, Aarau, Switzerland
| | - Jasmin Kuratli
- Infection Pathology Unit, Department of Pathobiology, Vetsuisse Faculty and Center for Applied Biotechnology and Molecular Medicine (CABMM), Institute of Veterinary Pathology, University of Zurich, Zurich, Switzerland
| | - Peter Vaupel
- Department of Radiation Oncology, Medical Center, University of Freiburg, Freiburg i.B, Germany
| | - Nicole Scherr
- Molecular Immunology Unit, Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Gerd Pluschke
- Molecular Immunology Unit, Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
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20
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Chaguza C, Yang M, Cornick JE, du Plessis M, Gladstone RA, Kwambana-Adams BA, Lo SW, Ebruke C, Tonkin-Hill G, Peno C, Senghore M, Obaro SK, Ousmane S, Pluschke G, Collard JM, Sigaùque B, French N, Klugman KP, Heyderman RS, McGee L, Antonio M, Breiman RF, von Gottberg A, Everett DB, Kadioglu A, Bentley SD. Bacterial genome-wide association study of hyper-virulent pneumococcal serotype 1 identifies genetic variation associated with neurotropism. Commun Biol 2020; 3:559. [PMID: 33033372 PMCID: PMC7545184 DOI: 10.1038/s42003-020-01290-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/11/2020] [Indexed: 12/19/2022] Open
Abstract
Hyper-virulent Streptococcus pneumoniae serotype 1 strains are endemic in Sub-Saharan Africa and frequently cause lethal meningitis outbreaks. It remains unknown whether genetic variation in serotype 1 strains modulates tropism into cerebrospinal fluid to cause central nervous system (CNS) infections, particularly meningitis. Here, we address this question through a large-scale linear mixed model genome-wide association study of 909 African pneumococcal serotype 1 isolates collected from CNS and non-CNS human samples. By controlling for host age, geography, and strain population structure, we identify genome-wide statistically significant genotype-phenotype associations in surface-exposed choline-binding (P = 5.00 × 10-08) and helicase proteins (P = 1.32 × 10-06) important for invasion, immune evasion and pneumococcal tropism to CNS. The small effect sizes and negligible heritability indicated that causation of CNS infection requires multiple genetic and other factors reflecting a complex and polygenic aetiology. Our findings suggest that certain pathogen genetic variation modulate pneumococcal survival and tropism to CNS tissue, and therefore, virulence for meningitis.
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Affiliation(s)
- Chrispin Chaguza
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK.
- Darwin College, University of Cambridge, Silver Street, Cambridge, UK.
| | - Marie Yang
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Jennifer E Cornick
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Mignon du Plessis
- Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa
- School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Rebecca A Gladstone
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Brenda A Kwambana-Adams
- NIHR Global Health Research Unit on Mucosal Pathogens, Division of Infection and Immunity, University College London, London, UK
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Stephanie W Lo
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Chinelo Ebruke
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Gerry Tonkin-Hill
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK
| | - Chikondi Peno
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- MRC Centre for Inflammation Research, Queens Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Madikay Senghore
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
- Center for Communicable Disease Dynamics, Department of Epidemiology, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Stephen K Obaro
- Division of Pediatric Infectious Disease, University of Nebraska Medical Center Omaha, Omaha, NE, USA
- International Foundation against Infectious Diseases in Nigeria, Abuja, Nigeria
| | - Sani Ousmane
- Centre de Recherche Médicale et Sanitaire, Niamey, Niger
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | | | - Betuel Sigaùque
- Centro de Investigação em Saúde da Manhiça, Maputo, Mozambique
| | - Neil French
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Keith P Klugman
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Robert S Heyderman
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- NIHR Global Health Research Unit on Mucosal Pathogens, Division of Infection and Immunity, University College London, London, UK
| | - Lesley McGee
- Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Martin Antonio
- Medical Research Council (MRC) Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Robert F Breiman
- Emory Global Health Institute, Emory University, Atlanta, GA, USA
| | - Anne von Gottberg
- Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa
- School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Dean B Everett
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
- MRC Centre for Inflammation Research, Queens Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Aras Kadioglu
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Stephen D Bentley
- Parasites and Microbes Programme, Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge, UK.
- Department of Pathology, University of Cambridge, Cambridge, UK.
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21
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Vandelannoote K, Pluschke G, Bolz M, Bratschi MW, Kerber S, Stinear TP, de Jong BC. Introduction of Mycobacterium ulcerans disease in the Bankim Health District of Cameroon follows damming of the Mapé River. PLoS Negl Trop Dis 2020; 14:e0008501. [PMID: 32886658 PMCID: PMC7473558 DOI: 10.1371/journal.pntd.0008501] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 06/19/2020] [Indexed: 11/18/2022] Open
Abstract
Buruli ulcer (BU) is an emerging ulcerative skin disease caused by infection with Mycobacterium ulcerans. Efforts to control its spread have been hampered by our limited understanding of M. ulcerans reservoirs and transmission, and the factors leading to the emergence of BU disease in a particular region. In this report we investigate an anecdotal link between damming the Mapé River in Cameroon and the emergence of BU in the Health Districts bordering Lake Bankim, the impoundment created by the Mapé dam. We used bacterial population genomics and molecular dating to find compelling support for a 2000 M. ulcerans introduction event that followed about 10 years after the filling of the newly created impoundment in 1988. We compared the genomic reconstructions with high-resolution satellite imagery to investigate what major environmental alterations might have driven the emergence of the new focus.
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Affiliation(s)
- Koen Vandelannoote
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Microbiology and Immunology, The University of Melbourne at the Doherty Institute for Infection & Immunity, Melbourne, Australia
| | - Gerd Pluschke
- Molecular Immunology, Swiss Tropical Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Miriam Bolz
- Molecular Immunology, Swiss Tropical Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Martin W. Bratschi
- Molecular Immunology, Swiss Tropical Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Sarah Kerber
- Molecular Immunology, Swiss Tropical Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Timothy P. Stinear
- Department of Microbiology and Immunology, The University of Melbourne at the Doherty Institute for Infection & Immunity, Melbourne, Australia
| | - Bouke C. de Jong
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
- * E-mail:
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22
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Abstract
Mycobacterial pathogens can be categorized into three broad groups: Mycobacterium tuberculosis complex causing tuberculosis, M. leprae and M. lepromatosis causing leprosy, and atypical mycobacteria, or non-tuberculous mycobacteria (NTM), responsible for a wide range of diseases. Among the NTMs, M. ulcerans is responsible for the neglected tropical skin disease Buruli ulcer (BU). Most pathogenic mycobacteria, including M. leprae, evade effector mechanisms of the humoral immune system by hiding and replicating inside host cells and are furthermore excellent modulators of host immune responses. In contrast, M. ulcerans replicates predominantly extracellularly, sheltered from host immune responses through the cytotoxic and immunosuppressive effects of mycolactone, a macrolide produced by the bacteria. In the year 2018, 208,613 new cases of leprosy and 2713 new cases of BU were reported to WHO, figures which are notoriously skewed by vast underreporting of these diseases.
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Affiliation(s)
- Katharina Röltgen
- Department of Pathology, Stanford School of Medicine, Stanford University, Stanford, CA, USA
| | - Gerd Pluschke
- Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.
- University of Basel, Basel, Switzerland.
| | - John Stewart Spencer
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Patrick Joseph Brennan
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Charlotte Avanzi
- Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
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23
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Warryn L, Dangy JP, Gersbach P, Gehringer M, Schäfer A, Ruf MT, Ruggli N, Altmann KH, Pluschke G. Development of an ELISA for the quantification of mycolactone, the cytotoxic macrolide toxin of Mycobacterium ulcerans. PLoS Negl Trop Dis 2020; 14:e0008357. [PMID: 32589646 PMCID: PMC7347236 DOI: 10.1371/journal.pntd.0008357] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 07/09/2020] [Accepted: 05/04/2020] [Indexed: 01/04/2023] Open
Abstract
Mycolactones, macrolide cytotoxins, are key virulence factors of Mycobacterium ulcerans, the etiological agent of the chronic necrotizing skin disease Buruli ulcer. There is urgent need for a simple point-of-care laboratory test for Buruli ulcer and mycolactone represents a promising target for the development of an immunological assay. However, for a long time, all efforts to generate mycolactone-specific antibodies have failed. By using a protein conjugate of a truncated non-toxic synthetic mycolactone derivative, we recently described generation of a set of mycolactone-specific monoclonal antibodies. Using the first mycolactone-specific monoclonal antibodies that we have described before, we were able to develop an antigen competition assay that detects mycolactones. By the systematic selection of a capturing antibody and a reporter molecule, and the optimization of assay conditions, we developed an ELISA that detects common natural variants of mycolactone with a limit of detection in the low nanomolar range. The mycolactone-specific ELISA described here will be a very useful tool for research on the biology of this macrolide toxin. After conversion into a simple point-of-care test format, the competition assay may have great potential as laboratory assay for both the diagnosis of Buruli ulcer and for the monitoring of treatment efficacy.
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Affiliation(s)
- Louisa Warryn
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Philipp Gersbach
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Zürich, Switzerland
| | - Matthias Gehringer
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Zürich, Switzerland
| | - Anja Schäfer
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Marie-Thérèse Ruf
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Nicolas Ruggli
- The Institute of Virology and Immunology IVI, Mittelhäusern, Switzerland
| | - Karl-Heinz Altmann
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Zürich, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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24
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Röltgen K, Pluschke G. Buruli ulcer: The Efficacy of Innate Immune Defense May Be a Key Determinant for the Outcome of Infection With Mycobacterium ulcerans. Front Microbiol 2020; 11:1018. [PMID: 32523571 PMCID: PMC7261859 DOI: 10.3389/fmicb.2020.01018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/24/2020] [Indexed: 12/18/2022] Open
Abstract
Buruli ulcer (BU) is a neglected, tropical infectious disease of the skin and the subcutaneous tissue caused by Mycobacterium ulcerans. This pathogen has emerged as a new species from a common ancestor with Mycobacterium marinum by acquisition of the virulence plasmid pMUM. The plasmid encodes enzymes required for the synthesis of the macrolide toxin mycolactone, which has cytotoxic and immunosuppressive activities. In advanced BU lesions, extracellular clusters of M. ulcerans reside in necrotic subcutaneous tissue and are protected from infiltrating leukocytes by the cytotoxic activity of secreted mycolactone. Several lines of evidence indicate that elements of the innate immune system eliminate in many cases the initial inoculum before bacterial clusters can form and that therefore exposure to M. ulcerans leads only in a minority of individuals to the characteristic chronic necrotizing BU lesions. It is assumed that phagocytes play a key role in early host defense against M. ulcerans. Antibodies against bacterial surface structures seem to have less potential to enhance innate immunity than TH1 cell responses. Precise innate and adaptive immune effector mechanisms leading to protective immunity are however unclear, complicating the development of effective vaccines, the most desired solution to control BU. The tuberculosis vaccine Mycobacterium bovis Bacillus Calmette–Guérin (BCG) has limited short-term protective activity against BU. Whether this effect is due to the broad antigenic cross-reactivity between M. bovis and M. ulcerans or is at least partly mediated by a non-specific enhanced responsiveness of innate immune cells to secondary stimulation, recently described as “trained immunity” or “innate immune memory” is unknown but has major implications for vaccine design. Current vaccine research and development activities are focusing on recombinant BCG, subunit vaccines with selected M. ulcerans proteins, and the neutralization of mycolactone.
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Affiliation(s)
- Katharina Röltgen
- Department of Pathology, Stanford School of Medicine, Stanford University, Stanford, CA, United States
| | - Gerd Pluschke
- Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
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25
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Piazena H, Müller W, Pendl W, von Ah S, Cap VH, Hug PJ, Sidler X, Pluschke G, Vaupel P. Thermal field formation during wIRA-hyperthermia: temperature measurements in skin and subcutis of piglets as a basis for thermotherapy of superficial tumors and local skin infections caused by thermosensitive microbial pathogens. Int J Hyperthermia 2020; 36:938-952. [PMID: 31535588 DOI: 10.1080/02656736.2019.1655594] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Purpose: The temporal and spatial formation of the temperature field and its changes during/upon water-filtered infrared-A (wIRA)-irradiation in porcine skin and subcutis were investigated in vivo in order to get a detailed physical basis for thermotherapy of superficial tumors and infections caused by thermosensitive microbial pathogens (e.g., Mycobacterium ulcerans causing Buruli ulcer). Methods: Local wIRA-hyperthermia was performed in 11 anesthetized piglets using 85.0 mW cm-2, 103.2 mW cm-2 and 126.5 mW cm-2, respectively. Invasive temperature measurements were carried out simultaneously in 1-min intervals using eight fiber-optical probes at different tissue depths between 2 and 20 mm, and by an IR thermometer at the skin surface. Results: Tissue temperature distribution depended on incident irradiance, exposure time, tissue depths and individual 'physiologies' of the animals. Temperature maxima were found at depths between 4 and 7 mm, exceeding skin surface temperatures by about 1-2 K. Tissue temperatures above 37 °C, necessary to eradicate M. ulcerans at depths <20 mm, were reached reliably. Conclusions: wIRA-hyperthermia may be considered as a novel therapeutic option for treatment of local skin infections caused by thermosensitive pathogens (e.g., in Buruli ulcer). To ensure temperatures required for heat treatment of superficial tumors deeper than 4 mm, the incident irradiance needed can be controlled either by (a) invasive temperature measurements or (b) control of skin surface temperature and considering possible temperature increases up to 1-2 K in underlying tissue.
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Affiliation(s)
- Helmut Piazena
- Medical Photobiology Group, Department of Internal Medicine, Charité-University Medicine Berlin , Berlin , Germany
| | - Werner Müller
- Physical Optics Consultant Office , Wetzlar , Germany
| | - Wolfgang Pendl
- Department of Farm Animals, Division of Swine Medicine, Vetsuisse Faculty, University of Zürich , Zürich , Switzerland
| | - Sereina von Ah
- Department of Farm Animals, Division of Swine Medicine, Vetsuisse Faculty, University of Zürich , Zürich , Switzerland
| | - Veronika H Cap
- Section of Anaesthesiology, Equine Department, Vetsuisse Faculty, University of Zürich , Zürich , Switzerland
| | - Petra J Hug
- Section of Anaesthesiology, Equine Department, Vetsuisse Faculty, University of Zürich , Zürich , Switzerland
| | - Xaver Sidler
- Department of Farm Animals, Division of Swine Medicine, Vetsuisse Faculty, University of Zürich , Zürich , Switzerland
| | - Gerd Pluschke
- Department of Medical Parasitology and Infection Biology, Molecular Immunology Unit, Swiss Tropical and Public Health Institute , Basel , Switzerland
| | - Peter Vaupel
- Department of Radiation Oncology, University Medical Center , Freiburg i. Breisgau , Germany
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26
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Gehringer M, Mäder P, Gersbach P, Pfeiffer B, Scherr N, Dangy JP, Pluschke G, Altmann KH. Configurationally Stabilized Analogs of M. ulcerans Exotoxins Mycolactones A and B Reveal the Importance of Side Chain Geometry for Mycolactone Virulence. Org Lett 2019; 21:5853-5857. [PMID: 31295000 DOI: 10.1021/acs.orglett.9b01947] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Mycolactones A/B (1a/b) are exotoxins of Mycobacterium ulcerans that are the molecular cause of Buruli ulcer. 1a/b represent a rapidly equilibrating mixture of Z/E isomers about the C4'═C5' double bond of the C5-side chain. Here, we describe the syntheses of mycolactone analogs with configurationally stable C5-side chains (2a, E mimetic; 2b/c, Z mimetics). Based on the cytotoxicity of 2a-c, the Δ4',5'-trans isomer of mycolactones A/B (1b) appears to be the major virulence factor.
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Affiliation(s)
- Matthias Gehringer
- Swiss Federal Institute of Technology (ETH) Zürich , Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences , Vladimir-Prelog-Weg 4 , 8093 Zürich , Switzerland
| | - Patrick Mäder
- Swiss Federal Institute of Technology (ETH) Zürich , Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences , Vladimir-Prelog-Weg 4 , 8093 Zürich , Switzerland
| | - Philipp Gersbach
- Swiss Federal Institute of Technology (ETH) Zürich , Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences , Vladimir-Prelog-Weg 4 , 8093 Zürich , Switzerland
| | - Bernhard Pfeiffer
- Swiss Federal Institute of Technology (ETH) Zürich , Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences , Vladimir-Prelog-Weg 4 , 8093 Zürich , Switzerland
| | - Nicole Scherr
- Swiss Tropical and Public Health Institute , Socinstrasse 57 , 4002 Basel , Switzerland
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute , Socinstrasse 57 , 4002 Basel , Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute , Socinstrasse 57 , 4002 Basel , Switzerland
| | - Karl-Heinz Altmann
- Swiss Federal Institute of Technology (ETH) Zürich , Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences , Vladimir-Prelog-Weg 4 , 8093 Zürich , Switzerland
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27
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Scherr N, Bieri R, Thomas SS, Chauffour A, Kalia NP, Schneide P, Ruf MT, Lamelas A, Manimekalai MSS, Grüber G, Ishii N, Suzuki K, Tanner M, Moraski GC, Miller MJ, Witschel M, Jarlier V, Pluschke G, Pethe K. Targeting the Mycobacterium ulcerans cytochrome bc 1:aa 3 for the treatment of Buruli ulcer. Nat Commun 2018; 9:5370. [PMID: 30560872 PMCID: PMC6299076 DOI: 10.1038/s41467-018-07804-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Accepted: 11/26/2018] [Indexed: 11/21/2022] Open
Abstract
Mycobacterium ulcerans is the causative agent of Buruli ulcer, a neglected tropical skin disease that is most commonly found in children from West and Central Africa. Despite the severity of the infection, therapeutic options are limited to antibiotics with severe side effects. Here, we show that M. ulcerans is susceptible to the anti-tubercular drug Q203 and related compounds targeting the respiratory cytochrome bc1:aa3. While the cytochrome bc1:aa3 is the primary terminal oxidase in Mycobacterium tuberculosis, the presence of an alternate bd-type terminal oxidase limits the bactericidal and sterilizing potency of Q203 against this bacterium. M. ulcerans strains found in Buruli ulcer patients from Africa and Australia lost all alternate terminal electron acceptors and rely exclusively on the cytochrome bc1:aa3 to respire. As a result, Q203 is bactericidal at low dose against M. ulcerans replicating in vitro and in mice, making the drug a promising candidate for Buruli ulcer treatment. Mycobacterium ulcerans is the causative agent of Buruli ulcer (BU). Existing anti-tubercular drugs have been used to treat the condition with varying success. Here, the authors show that a clinical-stage drug candidate for tuberculosis, Q203, is effective at killing M. ulcerans and is a promising therapeutic candidate for BU.
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Affiliation(s)
- Nicole Scherr
- Swiss Tropical and Public Health Institute, Basel, 4051, Switzerland.,University of Basel, Basel, 4001, Switzerland
| | - Raphael Bieri
- Swiss Tropical and Public Health Institute, Basel, 4051, Switzerland.,University of Basel, Basel, 4001, Switzerland
| | - Sangeeta S Thomas
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, Singapore, 636921, Singapore
| | - Aurélie Chauffour
- CR7, INSERM, U1135, Centre d'Immunologie et des Maladies Infectieuses, CIMI, Team E13 (Bactériologie), Sorbonne Universités, UPMC Université Paris 06, Paris, 75005, France
| | - Nitin Pal Kalia
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, Singapore, 636921, Singapore
| | | | - Marie-Thérèse Ruf
- Swiss Tropical and Public Health Institute, Basel, 4051, Switzerland.,University of Basel, Basel, 4001, Switzerland
| | - Araceli Lamelas
- Swiss Tropical and Public Health Institute, Basel, 4051, Switzerland.,University of Basel, Basel, 4001, Switzerland.,Red de Estudios Moleculares, AvanzadosInstituto de Ecología A. C., Xalapa, 91000, Veracruz, Mexico
| | - Malathy S S Manimekalai
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Gerhard Grüber
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Norihisa Ishii
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, 189-0002, Japan
| | - Koichi Suzuki
- Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Tokyo, 189-0002, Japan.,Department of Clinical Laboratory Science, Faculty of Medical Technology, Teikyo University, Tokyo, 173-8605, Japan
| | - Marcel Tanner
- Swiss Tropical and Public Health Institute, Basel, 4051, Switzerland.,University of Basel, Basel, 4001, Switzerland
| | - Garrett C Moraski
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59715, USA
| | - Marvin J Miller
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN, 46556, USA
| | | | - Vincent Jarlier
- CR7, INSERM, U1135, Centre d'Immunologie et des Maladies Infectieuses, CIMI, Team E13 (Bactériologie), Sorbonne Universités, UPMC Université Paris 06, Paris, 75005, France.,CNR-MyRMA, Bactériologie Hygiène, Hôpitaux Universitaires Pitie Salpêtrière-Charles Foix, Paris, 75013, France
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, 4051, Switzerland. .,University of Basel, Basel, 4001, Switzerland.
| | - Kevin Pethe
- Lee Kong Chian School of Medicine, Nanyang Technological University, Experimental Medicine Building, Singapore, 636921, Singapore. .,School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore.
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Lamelas A, Hamid AWM, Dangy JP, Hauser J, Jud M, Röltgen K, Hodgson A, Junghanss T, Harris SR, Parkhill J, Bentley SD, Pluschke G. Loss of Genomic Diversity in a Neisseria meningitidis Clone Through a Colonization Bottleneck. Genome Biol Evol 2018; 10:2102-2109. [PMID: 30060167 PMCID: PMC6110524 DOI: 10.1093/gbe/evy152] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/26/2018] [Indexed: 01/11/2023] Open
Abstract
Neisseria meningitidis is the leading cause of epidemic meningitis in the "meningitis belt" of Africa, where clonal waves of colonization and disease are observed. Point mutations and horizontal gene exchange lead to constant diversification of meningococcal populations during clonal spread. Maintaining a high genomic diversity may be an evolutionary strategy of meningococci that increases chances of fixing occasionally new highly successful "fit genotypes". We have performed a longitudinal study of meningococcal carriage and disease in northern Ghana by analyzing cerebrospinal fluid samples from all suspected meningitis cases and monitoring carriage of meningococci by twice yearly colonization surveys. In the framework of this study, we observed complete replacement of an A: sequence types (ST)-2859 clone by a W: ST-2881 clone. However, after a gap of 1 year, A: ST-2859 meningococci re-emerged both as colonizer and meningitis causing agent. Our whole genome sequencing analyses compared the A population isolated prior to the W colonization and disease wave with the re-emerging A meningococci. This analysis revealed expansion of one clone differing in only one nonsynonymous SNP from several isolates already present in the original A: ST-2859 population. The colonization bottleneck caused by the competing W meningococci thus resulted in a profound reduction in genomic diversity of the A meningococcal population.
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Affiliation(s)
- Araceli Lamelas
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Switzerland
- Red de Estudios Moleculares Avanzados, Instituto de Ecología A. C., Xalapa, Veracruz, México
| | - Abdul-Wahab M Hamid
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Switzerland
- Navrongo Health Research Centre, Ministry of Health, Navrongo, Ghana
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Switzerland
| | - Julia Hauser
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Switzerland
| | - Maja Jud
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Switzerland
| | - Katharina Röltgen
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Switzerland
| | - Abraham Hodgson
- Navrongo Health Research Centre, Ministry of Health, Navrongo, Ghana
- Research and Development Division, Ghana Health Service, Accra, Ghana
| | - Thomas Junghanss
- Section of Clinical Tropical Medicine, University Hospital Heidelberg, Germany
| | - Simon R Harris
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Julian Parkhill
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Stephen D Bentley
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Switzerland
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Röltgen K, Pluschke G, Johnson PDR, Fyfe J. Mycobacterium ulcerans DNA in Bandicoot Excreta in Buruli Ulcer-Endemic Area, Northern Queensland, Australia. Emerg Infect Dis 2018; 23:2042-2045. [PMID: 29148373 PMCID: PMC5708234 DOI: 10.3201/eid2312.170780] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
To identify potential reservoirs/vectors of Mycobacterium ulcerans in northern Queensland, Australia, we analyzed environmental samples collected from the Daintree River catchment area, to which Buruli ulcer is endemic, and adjacent coastal lowlands by species-specific PCR. We detected M. ulcerans DNA in soil, mosquitoes, and excreta of bandicoots, which are small terrestrial marsupials.
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30
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Röltgen K, Rose N, Ruggieri A, Warryn L, Scherr N, Pinho-Nascimento CA, Tamborrini M, Jaenisch T, Pluschke G. Development of Dengue Virus Serotype-Specific NS1 Capture Assays for the Rapid and Highly Sensitive Identification of the Infecting Serotype in Human Sera. J Immunol 2018; 200:3857-3866. [PMID: 29661824 DOI: 10.4049/jimmunol.1701790] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 03/26/2018] [Indexed: 12/29/2022]
Abstract
Dengue fever can be caused by one of four distinct dengue virus (DENV) serotypes that cocirculate in many parts of the world. Point of care serotype-specific nonstructural protein-1 (NS1) capture assays for the rapid serotyping of DENV in human sera would greatly support epidemiological surveillance and potentially also prognosis in individual patients. To ensure both serotype specificity and broad coverage of variants within serotypes, we have applied an innovative approach for the generation and selection of serotype-specific anti-NS1 mAbs. To elicit mAbs against conformational epitopes, NMRI mice were immunized with living HEK 293 transfectants expressing the native target Ags in multiple display on the cell surface. For each serotype, three different NS1 sequence variants were sequentially used for immunization of mice, hybridoma selection, and capture assay development, respectively. Selection of optimal combinations of capturing and detecting mAbs yielded highly sensitive and specific NS1 serotyping ELISAs (st-ELISAs) for the four serotypes. st-ELISA testing of 41 dengue patient sera showed a 100% concordance with the serotype determined by serotype-specific reverse transcriptase real-time quantitative PCR. The respective NS1 variants could be detected for ∼10 d after the onset of illness. Ab-dependent enhancement of DENV infections may be associated with a specific range of pre-existing anti-DENV serological Ab titers. Testing of patient sera with the developed st-ELISAs will not only be useful for epidemiological studies and surveillance, but it may also help to develop and validate assays that can distinguish protective versus enhancing Ab responses for risk assessment for the development of severe dengue disease in individual patients.
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Affiliation(s)
- Katharina Röltgen
- Molecular Immunology, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland; .,University of Basel, 4001 Basel, Switzerland
| | - Natalie Rose
- Molecular Immunology, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland.,University of Basel, 4001 Basel, Switzerland
| | - Alessia Ruggieri
- Department of Infectious Diseases, Molecular Virology, University of Heidelberg, 69120 Heidelberg, Germany
| | - Louisa Warryn
- Molecular Immunology, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland.,University of Basel, 4001 Basel, Switzerland
| | - Nicole Scherr
- Molecular Immunology, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland.,University of Basel, 4001 Basel, Switzerland
| | | | - Marco Tamborrini
- Molecular Immunology, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland.,University of Basel, 4001 Basel, Switzerland
| | - Thomas Jaenisch
- Department of Infectious Diseases, Section Clinical Tropical Medicine, Heidelberg University Hospital, 69120 Heidelberg, Germany
| | - Gerd Pluschke
- Molecular Immunology, Swiss Tropical and Public Health Institute, 4002 Basel, Switzerland.,University of Basel, 4001 Basel, Switzerland
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31
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Hardman N, Murray B, Zwickl M, Kolbinger F, Pluschke G. Application of Genetically-Engineered Anti-CEA Antibodies for Potential Immunotherapy of Colorectal Cancer. Int J Biol Markers 2018; 7:203-9. [PMID: 1431347 DOI: 10.1177/172460089200700315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Hitherto anti-CEA monoclonal antibodies (MAbs), normally of mouse origin, have been used primarily for clinical diagnosis of colorectal cancer, either as a tumor marker in serum to monitor tumor recurrence, or latterly as a means to localize in vivo CEA-bearing tumors and metastases in patients. In vivo diagnosis using mouse anti-CEA MAbs has so far had limited clinical utility because the antibodies elicit a strong anti-mouse immunoglobulin immune response on repeated administration in man. This problem has been addressed by the development of various strategies for “humanization” of mouse anti-CEA MAbs by genetic manipulation of immunoglobulin genes. Such humanized, engineered antibodies markedly attenuate the antigenic response directed against the MAb, such that safe, repeated administration to patients has become feasible. Such humanized anti-CEA antibodies can thus be radioactively-labelled and applied for in vivo monitoring and detection of recurrent malignant disease, or used for therapeutic strategies which similarly take advantage of the ability of the antibodies to target cytotoxic agents selectively to tumor cells. The application of these novel procedures for manipulating MAb structure presents entirely new opportunities for diagnosis and treatment of human colorectal cancer.
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Affiliation(s)
- N Hardman
- Department of Molecular Biology, CIBA-GEIGY Ltd., Basle-Switzerland
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32
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Tabah EN, Nsagha DS, Bissek ACZK, Njamnshi TN, Njih INN, Pluschke G, Njamnshi AK. Community knowledge, perceptions and attitudes regarding leprosy in rural Cameroon: The case of Ekondotiti and Mbonge health districts in the South-west Region. PLoS Negl Trop Dis 2018; 12:e0006233. [PMID: 29432474 PMCID: PMC5825164 DOI: 10.1371/journal.pntd.0006233] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 02/23/2018] [Accepted: 01/11/2018] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Although leprosy is one of the oldest diseases known to humanity, it remains largely misunderstood. Misconceptions about leprosy lead to stigma towards people with the disease. This study aimed at exploring the knowledge, perceptions and attitudes regarding leprosy in rural Cameroon. METHODS We carried out a cross-sectional community survey of 233 respondents aged 15-75 years, free from leprosy, and living in two rural health districts of the South-west Region of Cameroon. A questionnaire designed to evaluate knowledge, perceptions and attitudes about leprosy was used. Binary logistic regression was used to determine independent predictors of negative attitudes. RESULTS About 82% of respondents had heard about, and 64.4% knew someone with leprosy. Information on leprosy was mainly from community volunteers (40.6%), friends (38.0%), and the media (24%). Only 19.7% of respondents knew the cause of leprosy, and a considerable proportion linked it to a spell (25.3%), unclean blood (15.5%) and heredity (14.6%). About 72% knew that leprosy is curable and 86.3% would advise medical treatment. Attitudes towards leprosy patients were generally negative. Only 42% would shake hands, 32.6% would share the same plate, and 28.3% and 27% respectively, would allow their child to play or marry a person with leprosy. Furthermore, only 33.9% approved of participation of leprosy patients, and 42.9% of their employment. Independent predictors of negative attitudes were: the belief that leprosy is a curse; is caused by a germ; and having seen a leprosy patient. The negative attitudes were dampened by: the beliefs that leprosy is a punishment, is hereditary and is due to poor personal hygiene. CONCLUSION An awareness intervention using community volunteers and the media, with information on the cause of leprosy, its clinical manifestations and curability, and sensitization messages correcting the misconceptions and beliefs regarding leprosy, could improve the community knowledge and attitudes towards leprosy. This would ultimately contribute to the reduction of leprosy burden in the community.
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Affiliation(s)
- Earnest Njih Tabah
- National Yaws, Leishmaniasis, Leprosy and Buruli ulcer Control Programme, Department of disease, epidemics and pandemics control, Ministry of Public Health, Yaounde, Cameroon
- Department of Internal Medicine and Specialties, Faculty of Medicine and Biomedical Sciences, The University of Yaounde 1, Yaounde, Cameroon
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- Faculty of Science, University of Basel, Basel, Switzerland
| | - Dickson Shey Nsagha
- Department of Public Health and Hygiene, Faculty of Health Sciences, University of Buea, Buea, Cameroon
- Brain Research Africa Initiative (BRAIN), Yaounde, Cameroon
| | - Anne-Cécile Zoung-Kanyi Bissek
- Department of Internal Medicine and Specialties, Faculty of Medicine and Biomedical Sciences, The University of Yaounde 1, Yaounde, Cameroon
- Division of Operational Research in Health, Ministry of Public Health, Yaounde, Cameroon
| | - Theophilus Ngeh Njamnshi
- Department of Medical Laboratory Sciences, School of Health and Medical Sciences, Catholic University of Cameroon, Bamenda
| | | | - Gerd Pluschke
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- Faculty of Science, University of Basel, Basel, Switzerland
| | - Alfred Kongnyu Njamnshi
- Department of Internal Medicine and Specialties, Faculty of Medicine and Biomedical Sciences, The University of Yaounde 1, Yaounde, Cameroon
- Brain Research Africa Initiative (BRAIN), Yaounde, Cameroon
- Department of Neurology, Central Hospital Yaounde, Yaounde, Cameroon
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33
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Ispasanie E, Micoli F, Lamelas A, Keller D, Berti F, De Riccio R, Di Benedettoi R, Rondini S, Pluschke G. Spontaneous point mutations in the capsule synthesis locus leading to structural and functional changes of the capsule in serogroup A meningococcal populations. Virulence 2018; 9:1138-1149. [PMID: 30067453 PMCID: PMC6086313 DOI: 10.1080/21505594.2018.1467710] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 04/13/2018] [Indexed: 01/09/2023] Open
Abstract
Whole genome sequencing analysis of 100 Neisseria meningitidis serogroup A isolates has revealed that the csaABCD-ctrABCD-ctrEF capsule polysaccharide synthesis locus represents a spontaneous point mutation hotspot. Structural and functional properties of the capsule of 11 carriage and two disease isolates with non-synonymous point mutations or stop codons in capsule synthesis genes were analyzed for their capsular polysaccharide expression, recognition by antibodies and sensitivity to bactericidal killing. Eight of eleven carriage isolates presenting capsule locus mutations expressed no or reduced amounts of capsule. One isolate with a stop codon in the O-acetyltransferase gene expressed non-O-acetylated polysaccharide, and was not recognized by anti-capsule antibodies. Capsule and O-acetylation deficient mutants were resistant to complement deposition and killing mediated by anti-capsular antibodies, but not by anti-lipopolysaccharide antibodies. Two capsule polymerase mutants, one carriage and one case isolate, showed capsule over-expression and increased resistance against bactericidal activity of both capsule- and lipopolysaccharide-specific antibodies. Meningococci have developed multiple strategies for changing capsule expression and structure, which is relevant both for colonization and virulence. Here we show that point mutations in the capsule synthesis genes substantially contribute to the repertoire of genetic mechanisms in natural populations leading to variability in capsule expression.
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Affiliation(s)
- Emma Ispasanie
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | - Araceli Lamelas
- Red de Estudios Moleculares Avanzados, Instituto de Ecologia, A.C., Veracruz, México
| | - Dominique Keller
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | | | | | | | | | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Molecular Immunology Unit, Basel, Switzerland
- University of Basel, Basel, Switzerland
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34
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N’krumah RT, Koné B, Cissé G, Tanner M, Utzinger J, Pluschke G, Tiembré I. Characteristics and epidemiological profile of Buruli ulcer in the district of Tiassalé, south Côte d'Ivoire. Acta Trop 2017; 175:138-144. [PMID: 28034768 DOI: 10.1016/j.actatropica.2016.12.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 12/17/2016] [Accepted: 12/17/2016] [Indexed: 01/30/2023]
Abstract
Buruli ulcer (BU) is a cutaneous infectious disease caused by Mycobacterium ulcerans. It is the third most common mycobacterial disease in the world in the immunocompetent patient and second in Côte d'Ivoire after tuberculosis. This study aimed to assess the characteristics and epidemiological profile of BU in the district of Tiassalé, an important focus of the disease in south Côte d'Ivoire, in order to better direct actions for prevention and control. Retrospective clinical data of BU cases in the period 2005-2010 from all 19 district health centres were collected and linked with geographical and environmental survey data. A total of 1145 cases of BU were recorded between 2005 and 2010 in the district of Tiassalé. Children under the age of 15 years were the most affected (53.0%) with a higher prevalence among males compared to females (54.7% versus 45.3%). Among individuals aged 15-49 years, females had a higher prevalence than males (54.2% versus 45.8%). The villages of Ahondo, Léléblé and Taabo, located in close proximity to the man-made Lake Taabo that was constructed in the late 1970s by damming the Bandama River, and the village of Sokrogbo located downstream of the dam, showed the highest BU rates in the sub-prefecture of Taabo. In the sub-prefecture of Tiassalé, the villages of Affikro, Morokro and N'Zianouan, located near N'Zi River, a tributary of the Bandama River, were the most affected. The distribution of BU is associated with environmental patterns (i.e. distance between village and Lake Taabo or Bandama River and its tributary N'Zi River). Awareness campaigns, coupled with early diagnosis and improved clinical management of BU, have been implemented in the district of Tiassalé and the incidence of BU has declined.
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35
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Ruf MT, Steffen C, Bolz M, Schmid P, Pluschke G. Infiltrating leukocytes surround early Buruli ulcer lesions, but are unable to reach the mycolactone producing mycobacteria. Virulence 2017; 8:1918-1926. [PMID: 28873327 PMCID: PMC5810495 DOI: 10.1080/21505594.2017.1370530] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Affiliation(s)
- Marie-Thérèse Ruf
- a Swiss Tropical and Public Health Institute , Basel , Switzerland.,b University of Basel , Basel , Switzerland
| | - Christina Steffen
- c Department of Surgery , Cairns Hospital , Cairns , QLD , Australia
| | - Miriam Bolz
- a Swiss Tropical and Public Health Institute , Basel , Switzerland.,b University of Basel , Basel , Switzerland
| | - Peter Schmid
- a Swiss Tropical and Public Health Institute , Basel , Switzerland.,b University of Basel , Basel , Switzerland
| | - Gerd Pluschke
- a Swiss Tropical and Public Health Institute , Basel , Switzerland.,b University of Basel , Basel , Switzerland
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36
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Bibert S, Bratschi MW, Aboagye SY, Collinet E, Scherr N, Yeboah-Manu D, Beuret C, Pluschke G, Bochud PY. Susceptibility to Mycobacterium ulcerans Disease (Buruli ulcer) Is Associated with IFNG and iNOS Gene Polymorphisms. Front Microbiol 2017; 8:1903. [PMID: 29046669 PMCID: PMC5632961 DOI: 10.3389/fmicb.2017.01903] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/19/2017] [Indexed: 01/10/2023] Open
Abstract
Buruli ulcer (BU) is a chronic necrotizing disease of the skin and subcutaneous fat tissue. The causative agent, Mycobacterium ulcerans, produces mycolactone, a macrolide toxin, which causes apoptosis of mammalian cells. Only a small proportion of individuals exposed to M. ulcerans develop clinical disease, as surrounding macrophages may control the infection by bacterial killing at an early stage, while mycolactone concentration is still low. Otherwise, bacterial multiplication leads to in higher concentrations of mycolactone, with formation of necrotizing lesions that are no more accessible to immune cells. By typing a cohort of 96 Ghanaian BU patients and 384 endemic controls without BU, we show an association between BU and single nucleotide polymorphisms (SNPs) in iNOS (rs9282799) and IFNG (rs2069705). Both polymorphisms influence promoter activity in vitro. A previously reported SNP in SLC11A1 (NRAMP, rs17235409) tended to be associated with BU. Altogether, these data reflect the importance of IFNG signaling in early defense against M. ulcerans infection.
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Affiliation(s)
- Stéphanie Bibert
- Infectious Diseases Service, Department of Medicine, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland
| | - Martin W Bratschi
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Samuel Y Aboagye
- Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Emilie Collinet
- Infectious Diseases Service, Department of Medicine, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland
| | - Nicole Scherr
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Dorothy Yeboah-Manu
- Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Christian Beuret
- Spiez Laboratory, Federal Office for Civil Protection, Spiez, Switzerland
| | - Gerd Pluschke
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Pierre-Yves Bochud
- Infectious Diseases Service, Department of Medicine, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland
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37
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Lamelas A, Hauser J, Dangy JP, Hamid AWM, Röltgen K, Abdul Sater MR, Hodgson A, Sie A, Junghanss T, Harris SR, Parkhill J, Bentley SD, Pluschke G. Emergence and genomic diversification of a virulent serogroup W:ST-2881(CC175) Neisseria meningitidis clone in the African meningitis belt. Microb Genom 2017; 3:e000120. [PMID: 29026659 PMCID: PMC5610715 DOI: 10.1099/mgen.0.000120] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 05/10/2017] [Indexed: 12/21/2022] Open
Abstract
Countries of the African 'meningitis belt' are susceptible to meningococcal meningitis outbreaks. While in the past major epidemics have been primarily caused by serogroup A meningococci, W strains are currently responsible for most of the cases. After an epidemic in Mecca in 2000, W:ST-11 strains have caused many outbreaks worldwide. An unrelated W:ST-2881 clone was described for the first time in 2002, with the first meningitis cases caused by these bacteria reported in 2003. Here we describe results of a comparative whole-genome analysis of 74 W:ST-2881 strains isolated within the framework of two longitudinal colonization and disease studies conducted in Ghana and Burkina Faso. Genomic data indicate that the W:ST-2881 clone has emerged from Y:ST-175(CC175) bacteria by capsule switching. The circulating W:ST-2881 populations were composed of a variety of closely related but distinct genomic variants with no systematic differences between colonization and disease isolates. Two distinct and geographically clustered phylogenetic clonal variants were identified in Burkina Faso and a third in Ghana. On the basis of the presence or absence of 17 recombination fragments, the Ghanaian variant could be differentiated into five clusters. All 25 Ghanaian disease isolates clustered together with 23 out of 40 Ghanaian isolates associated with carriage within one cluster, indicating that W:ST-2881 clusters differ in virulence. More than half of the genes affected by horizontal gene transfer encoded proteins of the 'cell envelope' and the 'transport/binding protein' categories, which indicates that exchange of non-capsular antigens plays an important role in immune evasion.
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Affiliation(s)
- Araceli Lamelas
- 1Swiss Tropical and Public Health Institute, Socinstrasse 57, 4051 Basel, Switzerland.,2Red de Estudios Moleculares Avanzados, Instituto de Ecologia, Veracruz, Mexico
| | - Julia Hauser
- 1Swiss Tropical and Public Health Institute, Socinstrasse 57, 4051 Basel, Switzerland.,3University of Basel, Basel, Switzerland
| | - Jean-Pierre Dangy
- 1Swiss Tropical and Public Health Institute, Socinstrasse 57, 4051 Basel, Switzerland.,3University of Basel, Basel, Switzerland
| | - Abdul-Wahab M Hamid
- 3University of Basel, Basel, Switzerland.,4Navrongo Health Research Centre, Navrongo, Ghana
| | - Katharina Röltgen
- 1Swiss Tropical and Public Health Institute, Socinstrasse 57, 4051 Basel, Switzerland.,3University of Basel, Basel, Switzerland
| | - Mohamad R Abdul Sater
- 1Swiss Tropical and Public Health Institute, Socinstrasse 57, 4051 Basel, Switzerland.,3University of Basel, Basel, Switzerland
| | | | - Ali Sie
- 5Center de Recherche en Sante de Nouna, Nouna, Burkina Faso
| | - Thomas Junghanss
- 6Section of Clinical Tropical Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Simon R Harris
- 7Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
| | - Julian Parkhill
- 7Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
| | - Stephen D Bentley
- 7Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
| | - Gerd Pluschke
- 1Swiss Tropical and Public Health Institute, Socinstrasse 57, 4051 Basel, Switzerland.,3University of Basel, Basel, Switzerland
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Bieri R, Scherr N, Ruf MT, Dangy JP, Gersbach P, Gehringer M, Altmann KH, Pluschke G. The Macrolide Toxin Mycolactone Promotes Bim-Dependent Apoptosis in Buruli Ulcer through Inhibition of mTOR. ACS Chem Biol 2017; 12:1297-1307. [PMID: 28294596 DOI: 10.1021/acschembio.7b00053] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Mycolactone, the macrolide exotoxin produced by Mycobacterium ulcerans, is central to the pathogenesis of the chronic necrotizing skin disease Buruli ulcer (BU). Here we show that mycolactone acts as an inhibitor of the mechanistic Target of Rapamycin (mTOR) signaling pathway by interfering with the assembly of the two distinct mTOR protein complexes mTORC1 and mTORC2, which regulate different cellular processes. Inhibition of the assembly of the rictor containing mTORC2 complex by mycolactone prevents phosphorylation of the serine/threonine protein kinase Akt. The associated inactivation of Akt leads to the dephosphorylation and activation of the Akt-targeted transcription factor FoxO3. Subsequent up-regulation of the FoxO3 target gene BCL2L11 (Bim) increases expression of the pro-apoptotic regulator Bim, driving mycolactone treated mammalian cells into apoptosis. The central role of Bim-dependent apoptosis in BU pathogenesis deduced from our experiments with cultured mammalian cells was further verified in an experimental M. ulcerans infection model. As predicted by the model, M. ulcerans infected Bim knockout mice did not develop necrotic BU lesions with large clusters of extracellular bacteria, but were able to contain the mycobacterial multiplication. Our findings provide a new coherent and comprehensive concept of BU pathogenesis.
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Affiliation(s)
- Raphael Bieri
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland
- University of Basel, Petersplatz
1, 4003 Basel, Switzerland
| | - Nicole Scherr
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland
- University of Basel, Petersplatz
1, 4003 Basel, Switzerland
| | - Marie-Thérèse Ruf
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland
- University of Basel, Petersplatz
1, 4003 Basel, Switzerland
| | - Jean-Pierre Dangy
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland
- University of Basel, Petersplatz
1, 4003 Basel, Switzerland
| | - Philipp Gersbach
- Department
of Chemistry and Applied Biosciences, Institute of Pharmaceutical
Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Vladimir-Prelog-Weg 1-5/10, 8093 Zürich, Switzerland
| | - Matthias Gehringer
- Department
of Chemistry and Applied Biosciences, Institute of Pharmaceutical
Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Vladimir-Prelog-Weg 1-5/10, 8093 Zürich, Switzerland
| | - Karl-Heinz Altmann
- Department
of Chemistry and Applied Biosciences, Institute of Pharmaceutical
Sciences, Swiss Federal Institute of Technology (ETH) Zürich, Vladimir-Prelog-Weg 1-5/10, 8093 Zürich, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland
- University of Basel, Petersplatz
1, 4003 Basel, Switzerland
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Ruf MT, Andreoli A, Vujic G, Itin P, Pluschke G, Schmid P. Exudate collection using wound sponges-An easy, non-invasive and reliable method to explore protease activities in ulcers. Wound Repair Regen 2017; 25:320-326. [PMID: 28370804 DOI: 10.1111/wrr.12517] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 01/19/2017] [Accepted: 02/01/2017] [Indexed: 12/22/2022]
Abstract
Proteases are important for wound healing, but in excessive amounts or left uncontrolled, they may cause healing impairment or other severe wound complications. Point-of-care testing for protease activities in wounds may be useful for monitoring the effectiveness of treatment, and for early identification of wounds that potentially fail to heal. Here we describe an easy, noninvasive method to collect wound fluid for evaluating the protease milieu of wounds. Wound fluids were collected using sterile sponges applied between wound surface and normal wound dressing. Wound fluid could be easily squeezed or centrifuged out of the sponges and was tested for gelatinase (MMP-2 and MMP-9) activities by gel zymography. In addition, we measured polymorphonuclear granulocyte elastase levels by ELISA. Both gelatinases were remarkably stable in sponge derived fluids, as no significant loss was observed even when samples were stored for 3 days at room temperature. Protease levels were highly diverse amongst patients and, in some cases, showed substantial variations in the course of the treatment. The here described wound sponge approach represents a patient-friendly and reliable method to collect wound fluid for evaluating wound healing relevant biomarkers, such as matrix metalloproteinases.
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Affiliation(s)
- Marie-Thérèse Ruf
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Arianna Andreoli
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Gabriel Vujic
- Department of Dermatology, University Hospital Basel, Basel, Switzerland
| | - Peter Itin
- Department of Dermatology, University Hospital Basel, Basel, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Peter Schmid
- Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
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Kpeli G, Buultjens AH, Giulieri S, Owusu-Mireku E, Aboagye SY, Baines SL, Seemann T, Bulach D, Gonçalves da Silva A, Monk IR, Howden BP, Pluschke G, Yeboah-Manu D, Stinear T. Genomic analysis of ST88 community-acquired methicillin resistant Staphylococcus aureus in Ghana. PeerJ 2017; 5:e3047. [PMID: 28265515 PMCID: PMC5333547 DOI: 10.7717/peerj.3047] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 01/30/2017] [Indexed: 01/11/2023] Open
Abstract
Background The emergence and evolution of community-acquired methicillin resistant Staphylococcus aureus (CA-MRSA) strains in Africa is poorly understood. However, one particular MRSA lineage called ST88, appears to be rapidly establishing itself as an “African” CA-MRSA clone. In this study, we employed whole genome sequencing to provide more information on the genetic background of ST88 CA-MRSA isolates from Ghana and to describe in detail ST88 CA-MRSA isolates in comparison with other MRSA lineages worldwide. Methods We first established a complete ST88 reference genome (AUS0325) using PacBio SMRT sequencing. We then used comparative genomics to assess relatedness among 17 ST88 CA-MRSA isolates recovered from patients attending Buruli ulcer treatment centres in Ghana, three non-African ST88s and 15 other MRSA lineages. Results We show that Ghanaian ST88 forms a discrete MRSA lineage (harbouring SCCmec-IV [2B]). Gene content analysis identified five distinct genomic regions enriched among ST88 isolates compared with the other S. aureus lineages. The Ghanaian ST88 isolates had only 658 core genome SNPs and there was no correlation between phylogeny and geography, suggesting the recent spread of this clone. The lineage was also resistant to multiple classes of antibiotics including β-lactams, tetracycline and chloramphenicol. Discussion This study reveals that S. aureus ST88-IV is a recently emerging and rapidly spreading CA-MRSA clone in Ghana. The study highlights the capacity of small snapshot genomic studies to provide actionable public health information in resource limited settings. To our knowledge this is the first genomic assessment of the ST88 CA-MRSA clone.
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Affiliation(s)
- Grace Kpeli
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana; Department of Molecular Parasitology and Immunology, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Andrew H Buultjens
- Department of Microbiology and Immunology, Doherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne , Melbourne, VIC , Australia
| | - Stefano Giulieri
- Department of Microbiology and Immunology, Doherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne , Melbourne, VIC , Australia
| | - Evelyn Owusu-Mireku
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana , Accra , Ghana
| | - Samuel Y Aboagye
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana , Accra , Ghana
| | - Sarah L Baines
- Department of Microbiology and Immunology, Doherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne , Melbourne, VIC , Australia
| | - Torsten Seemann
- Department of Microbiology and Immunology, Doherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia; University of Melbourne, Victorian Life Sciences Computation Initiative, Melbourne, VIC, Australia
| | - Dieter Bulach
- Department of Microbiology and Immunology, Doherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia; University of Melbourne, Victorian Life Sciences Computation Initiative, Melbourne, VIC, Australia
| | - Anders Gonçalves da Silva
- Department of Microbiology and Immunology, Doherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne , Melbourne, VIC , Australia
| | - Ian R Monk
- Department of Microbiology and Immunology, Doherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne , Melbourne, VIC , Australia
| | - Benjamin P Howden
- Department of Microbiology and Immunology, Doherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, VIC, Australia; Department of Microbiology and Immunology, Microbiological Diagnostic Unit Public Health Laboratory, Doherty Institute for Infection & Immunity, University of Melbourne, Melbourne, VIC, Australia; Department of Infectious Diseases, Austin Health, Heidelberg, VIC, Australia
| | - Gerd Pluschke
- Department of Molecular Parasitology and Immunology, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Dorothy Yeboah-Manu
- Department of Bacteriology, Noguchi Memorial Institute for Medical Research, University of Ghana , Accra , Ghana
| | - Timothy Stinear
- Department of Microbiology and Immunology, Doherty Applied Microbial Genomics, Doherty Institute for Infection and Immunity, University of Melbourne , Melbourne, VIC , Australia
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Favuzza P, Guffart E, Tamborrini M, Scherer B, Dreyer AM, Rufer AC, Erny J, Hoernschemeyer J, Thoma R, Schmid G, Gsell B, Lamelas A, Benz J, Joseph C, Matile H, Pluschke G, Rudolph MG. Structure of the malaria vaccine candidate antigen CyRPA and its complex with a parasite invasion inhibitory antibody. eLife 2017; 6. [PMID: 28195038 PMCID: PMC5349852 DOI: 10.7554/elife.20383] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 02/06/2017] [Indexed: 12/02/2022] Open
Abstract
Invasion of erythrocytes by Plasmodial merozoites is a composite process involving the interplay of several proteins. Among them, the Plasmodium falciparum Cysteine-Rich Protective Antigen (PfCyRPA) is a crucial component of a ternary complex, including Reticulocyte binding-like Homologous protein 5 (PfRH5) and the RH5-interacting protein (PfRipr), essential for erythrocyte invasion. Here, we present the crystal structures of PfCyRPA and its complex with the antigen-binding fragment of a parasite growth inhibitory antibody. PfCyRPA adopts a 6-bladed β-propeller structure with similarity to the classic sialidase fold, but it has no sialidase activity and fulfills a purely non-enzymatic function. Characterization of the epitope recognized by protective antibodies may facilitate design of peptidomimetics to focus vaccine responses on protective epitopes. Both in vitro and in vivo anti-PfCyRPA and anti-PfRH5 antibodies showed more potent parasite growth inhibitory activity in combination than on their own, supporting a combined delivery of PfCyRPA and PfRH5 in vaccines. DOI:http://dx.doi.org/10.7554/eLife.20383.001 Malaria is one of the deadliest infectious diseases worldwide, killing over 400,000 people a year. About 200 million people are infected every year, placing a huge social and medical burden especially on developing countries. Microscopic parasites known as Plasmodium are responsible for causing this disease. Plasmodium parasites have a complex life cycle involving both mosquito and mammal hosts. This includes a stage where the parasites infect the mammal’s red blood cells, which causes the symptoms of the disease. In 2012, a team of researchers discovered that a protein called CyRPA forms a group (or ‘complex’) with several other proteins to allow the parasites to enter red blood cells. Developing a vaccine is one of the most promising approaches to prevent malaria. Vaccines help the body to recognise and fight an invading microbe by triggering an immune response that results in the production of proteins called antibodies, which can bind to specific molecules on the surface of the microbe. If the microbe later enters the body, these antibodies can be produced quickly to eliminate the microbe before it causes disease. However, efforts to develop a highly effective vaccine against malaria have so far been unsuccessful. Favuzza et al. – including some of the researchers involved in the 2012 work – used a technique called X-ray crystallography to investigate the three-dimensional structure of the CyRPA protein. The experiments show that an antibody is able to bind to a region of CyRPA – a designated ‘protective epitope’ – that is similar in the CyRPA proteins of all Plasmodium falciparum strains. These antibodies can prevent the parasite from entering the red blood cells, and vaccines containing CyRPA may therefore be effective at protecting individuals from malaria. The findings of Favuzza et al. also suggest that using CyRPA in combination with another protein in the complex called RH5 could make the vaccine more powerful as it would make it harder for the parasite to become resistant. The next step following on from this work is to design a vaccine containing protective CyRPA epitopes that triggers an immune response in mammals that is strong enough to reduce the numbers of parasites in the blood. A future challenge will be to develop a vaccine that combines several proteins involved in different stages of the parasite’s life cycle to provide full protection against malaria. DOI:http://dx.doi.org/10.7554/eLife.20383.002
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Affiliation(s)
- Paola Favuzza
- Medical Parasitology and Infection Biology Department, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Elena Guffart
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Marco Tamborrini
- Medical Parasitology and Infection Biology Department, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Bianca Scherer
- Medical Parasitology and Infection Biology Department, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Anita M Dreyer
- Medical Parasitology and Infection Biology Department, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Arne C Rufer
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Johannes Erny
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Joerg Hoernschemeyer
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Ralf Thoma
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Georg Schmid
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Bernard Gsell
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Araceli Lamelas
- Medical Parasitology and Infection Biology Department, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Joerg Benz
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Catherine Joseph
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Hugues Matile
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Gerd Pluschke
- Medical Parasitology and Infection Biology Department, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Markus G Rudolph
- Roche Pharmaceutical Research and Early Development, Small Molecule Research, Roche Innovation Center Basel, F Hoffmann-La Roche Ltd., Basel, Switzerland
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Cornick JE, Tastan Bishop Ö, Yalcin F, Kiran AM, Kumwenda B, Chaguza C, Govindpershad S, Ousmane S, Senghore M, du Plessis M, Pluschke G, Ebruke C, McGee L, Sigaùque B, Collard JM, Bentley SD, Kadioglu A, Antonio M, von Gottberg A, French N, Klugman KP, Heyderman RS, Alderson M, Everett DB. The global distribution and diversity of protein vaccine candidate antigens in the highly virulent Streptococcus pnuemoniae serotype 1. Vaccine 2017; 35:972-980. [PMID: 28081968 PMCID: PMC5287219 DOI: 10.1016/j.vaccine.2016.12.037] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 11/29/2016] [Accepted: 12/15/2016] [Indexed: 11/28/2022]
Abstract
Serotype 1 is one of the most common causes of pneumococcal disease worldwide. Pneumococcal protein vaccines are currently being developed as an alternate intervention strategy to pneumococcal conjugate vaccines. Pre-requisites for an efficacious pneumococcal protein vaccine are universal presence and minimal variation of the target antigen in the pneumococcal population, and the capability to induce a robust human immune response. We used in silico analysis to assess the prevalence of seven protein vaccine candidates (CbpA, PcpA, PhtD, PspA, SP0148, SP1912, SP2108) among 445 serotype 1 pneumococci from 26 different countries, across four continents. CbpA (76%), PspA (68%), PhtD (28%), PcpA (11%) were not universally encoded in the study population, and would not provide full coverage against serotype 1. PcpA was widely present in the European (82%), but not in the African (2%) population. A multi-valent vaccine incorporating CbpA, PcpA, PhtD and PspA was predicted to provide coverage against 86% of the global population. SP0148, SP1912 and SP2108 were universally encoded and we further assessed their predicted amino acid, antigenic and structural variation. Multiple allelic variants of these proteins were identified, different allelic variants dominated in different continents; the observed variation was predicted to impact the antigenicity and structure of two SP0148 variants, one SP1912 variant and four SP2108 variants, however these variants were each only present in a small fraction of the global population (<2%). The vast majority of the observed variation was predicted to have no impact on the efficaciousness of a protein vaccine incorporating a single variant of SP0148, SP1912 and/or SP2108 from S. pneumoniae TIGR4. Our findings emphasise the importance of taking geographic differences into account when designing global vaccine interventions and support the continued development of SP0148, SP1912 and SP2108 as protein vaccine candidates against this important pneumococcal serotype.
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Affiliation(s)
- Jennifer E Cornick
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi; Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool L69 7BE, UK.
| | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa
| | - Feyruz Yalcin
- Pathogen Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
| | - Anmol M Kiran
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi; Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool L69 7BE, UK
| | - Benjamin Kumwenda
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | - Chrispin Chaguza
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi; Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool L69 7BE, UK
| | - Shanil Govindpershad
- Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, A Division of the National Health Laboratory Service, Johannesburg, South Africa; School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Sani Ousmane
- Centre de Recherche Médicale et Sanitaire, Niamey, Niger
| | - Madikay Senghore
- Medical Research Council, Banjul, Gambia; Division of Translational and Systems Medicine, Microbiology and Infection Unit, The University of Warwick, UK
| | - Mignon du Plessis
- Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, A Division of the National Health Laboratory Service, Johannesburg, South Africa; School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | | | - Lesley McGee
- Centers for Disease Control and Prevention, Atlanta, USA
| | - Beutel Sigaùque
- Centro de Investigação em Saúde da Manhiça, Maputo, Mozambique
| | | | - Stephen D Bentley
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, South Africa
| | - Aras Kadioglu
- Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool L69 7BE, UK
| | - Martin Antonio
- Medical Research Council, Banjul, Gambia; Division of Translational and Systems Medicine, Microbiology and Infection Unit, The University of Warwick, UK; Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Anne von Gottberg
- Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, A Division of the National Health Laboratory Service, Johannesburg, South Africa; School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Neil French
- Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool L69 7BE, UK
| | - Keith P Klugman
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, USA
| | - Robert S Heyderman
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | | | - Dean B Everett
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi; Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool L69 7BE, UK
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Kpeli G, Otchere I, Lamelas A, Buultjens A, Bulach D, Baines S, Seemann T, Giulieri S, Nakobu Z, Aboagye S, Owusu-Mireku E, Danso E, Hauser J, Hinic V, Pluschke G, Stinear T, Yeboah-Manu D. DRUG RESISTANCE AND GENETIC PROFILE OF BACTERIAL SPECIES ASSOCIATED WITH BURULI ULCER WOUND INFECTIONS IN TWO DISTRICTS OF GHANA. BMJ Glob Health 2017. [DOI: 10.1136/bmjgh-2016-000260.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Tabah EN, Nsagha DS, Bissek ACZK, Bratschi MW, Njamnshi TN, Pluschke G, Njamnshi AK. Correction: The Burden of Leprosy in Cameroon: Fifteen Years into the Post-elimination Era. PLoS Negl Trop Dis 2017; 11:e0005305. [PMID: 28099459 PMCID: PMC5242423 DOI: 10.1371/journal.pntd.0005305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pntd.0005012.].
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Owusu E, Newman MJ, Akumwena A, Bannerman E, Pluschke G. Evaluating decontamination protocols for the isolation of Mycobacterium ulcerans from swabs. BMC Microbiol 2017; 17:2. [PMID: 28056807 PMCID: PMC5217313 DOI: 10.1186/s12866-016-0918-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 12/20/2016] [Indexed: 11/22/2022] Open
Abstract
Background Mycobacterium ulcerans (M. ulcerans) is the causative agent of Buruli Ulcer (BU) disease. In order to inhibit the growth of the microbial contaminants during culture of M. ulcerans, it is necessary to decontaminate BU samples with effective chemical agents. This study aimed at investigating some selected chemicals as potential decontamination agents for the isolation of M. ulcerans from swabs. Results Povidone iodine at 0.5 and 1% exhibited the lowest contamination and recovery rate for microbial contaminants and M. ulcerans. The most effective decontamination method was the protocol using 2% cetylpyridinium chloride/4% sodium chloride (recovery rate = 53%, contamination rate = 14%). The observed difference between the recovery rate of 2% CPC/4% NaC and the other protocols was however not statistically significant (p = 0.76). Conclusions Two percent (2%) cetylpyridinium chloride/4% sodium chloride can be conveniently used as an alternative decontamination method for the isolation of M. ulcerans from swabs.
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Affiliation(s)
- Enid Owusu
- Department of Medical Laboratory Sciences, School of Biomedical and Allied Health Sciences, University of Ghana, Accra, Ghana.
| | - Mercy J Newman
- Department of Medical Microbiology, School of Biomedical and Allied Health Sciences, University of Ghana, Accra, Ghana
| | - Amos Akumwena
- Department of Medical Microbiology, School of Biomedical and Allied Health Sciences, University of Ghana, Accra, Ghana
| | - Elizabeth Bannerman
- Department of Medical Microbiology, School of Biomedical and Allied Health Sciences, University of Ghana, Accra, Ghana
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Yeboah-Manu D, Kpeli G, Owusu-Mireku E, Hauser J, Pluschke G. Longitudinal assessment of the bacterial burden of buruli ulcer wounds during treatment. Biomed Biotechnol Res J 2017. [DOI: 10.4103/bbrj.bbrj_37_17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Bénard A, Sala C, Pluschke G. Mycobacterium ulcerans Mouse Model Refinement for Pre-Clinical Profiling of Vaccine Candidates. PLoS One 2016; 11:e0167059. [PMID: 27893778 PMCID: PMC5125663 DOI: 10.1371/journal.pone.0167059] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 11/08/2016] [Indexed: 11/30/2022] Open
Abstract
Buruli Ulcer is a neglected tropical disease leading to extensive disabilities and morbidity in West Africa. In this paper we sought to characterize various strains of Mycobacterium ulcerans (M.ulcerans) with different origins and laboratory passage records while refining a mouse model for Buruli ulcer. We described, compared and followed the kinetics of the histo-pathological outcome of infection of a collection of strains at various anatomical sites of infection in order to find a suitable model for further immunization studies. Moreover we compared the outcome of infection in C57Bl/6 and Balbc/J mice. Specifically we described thoroughly one M. ulcerans strain characterized by slow growth rate and limited tissue necrosis, which presents close ressemblance with the infection kinetics in humans. This strain caused macrophages as well as T and B cells infiltration, correlating with mycobacterial proliferation at the site of infection as well as in the draining lymph nodes, making it a suitable strain to screen vaccine candidates efficacy.
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Affiliation(s)
- Angèle Bénard
- Swiss Tropical and Public Health Institute, Basel, Switzerland
- * E-mail:
| | - Claudia Sala
- Global Health Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
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Rose N, Pinho-Nascimento CA, Ruggieri A, Favuzza P, Tamborrini M, Roth H, Baroni de Moraes MT, Matile H, Jänisch T, Pluschke G, Röltgen K. Generation of monoclonal antibodies against native viral proteins using antigen-expressing mammalian cells for mouse immunization. BMC Biotechnol 2016; 16:83. [PMID: 27876044 PMCID: PMC5120561 DOI: 10.1186/s12896-016-0314-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/01/2016] [Indexed: 01/02/2023] Open
Abstract
Background Due to their rising incidence and progressive geographical spread, infections with mosquito-borne viruses, such as dengue (DENV), chikungunya and zika virus, have developed into major public health challenges. Since all of these viruses may cause similar symptoms and can occur in concurrent epidemics, tools for their differential diagnosis and epidemiological monitoring are of urgent need. Results Here we report the application of a novel strategy to rapidly generate monoclonal antibodies (mAbs) against native viral antigens, exemplified for the DENV nonstructural glycoprotein 1 (NS1). The described system is based on the immunization of mice with transfected mammalian cells expressing the target antigens in multiple displays on their cell surface and thereby presenting them efficiently to the host immune system in their native conformation. By applying this cell-based approach to the DENV NS1 protein of serotypes 1 (D1NS1) and 4 (D4NS1), we were able to rapidly generate panels of DENV NS1 serotype cross-reactive, as well as D1NS1- and D4NS1 serotype-specific mAbs. Our data show that the generated mAbs were capable of recognizing the endogenous NS1 protein in DENV-containing biological samples. Conclusion The use of this novel immunization strategy, allows for a fast and efficient generation of hybridoma cell lines, producing mAbs against native viral antigens. Envisaged applications of the mAbs include the development of test platforms enabling a differentiation of the DENV serotypes and high resolution immunotyping for epidemiological studies. Electronic supplementary material The online version of this article (doi:10.1186/s12896-016-0314-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Natalie Rose
- Swiss Tropical and Public Health Institute, Molecular Immunology, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | - Alessia Ruggieri
- Department of Infectious Diseases, University of Heidelberg, Molecular Virology, Heidelberg, Germany
| | - Paola Favuzza
- Swiss Tropical and Public Health Institute, Molecular Immunology, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Marco Tamborrini
- Swiss Tropical and Public Health Institute, Molecular Immunology, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Hanna Roth
- Department of Infectious Diseases, University of Heidelberg, Molecular Virology, Heidelberg, Germany
| | | | - Hugues Matile
- Swiss Tropical and Public Health Institute, Molecular Immunology, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Thomas Jänisch
- Section Clinical Tropical Medicine, Department of Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Molecular Immunology, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Katharina Röltgen
- Swiss Tropical and Public Health Institute, Molecular Immunology, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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Chaguza C, Cornick JE, Harris SR, Andam CP, Bricio-Moreno L, Yang M, Yalcin F, Ousmane S, Govindpersad S, Senghore M, Ebruke C, Du Plessis M, Kiran AM, Pluschke G, Sigauque B, McGee L, Klugman KP, Turner P, Corander J, Parkhill J, Collard JM, Antonio M, von Gottberg A, Heyderman RS, French N, Kadioglu A, Hanage WP, Everett DB, Bentley SD. Understanding pneumococcal serotype 1 biology through population genomic analysis. BMC Infect Dis 2016; 16:649. [PMID: 27821148 PMCID: PMC5100261 DOI: 10.1186/s12879-016-1987-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 10/30/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pneumococcus kills over one million children annually and over 90 % of these deaths occur in low-income countries especially in Sub-Saharan Africa (SSA) where HIV exacerbates the disease burden. In SSA, serotype 1 pneumococci particularly the endemic ST217 clone, causes majority of the pneumococcal disease burden. To understand the evolution of the virulent ST217 clone, we analysed ST217 whole genomes from isolates sampled from African and Asian countries. METHODS We analysed 226 whole genome sequences from the ST217 lineage sampled from 9 African and 4 Asian countries. We constructed a whole genome alignment and used it for phylogenetic and coalescent analyses. We also screened the genomes to determine presence of antibiotic resistance conferring genes. RESULTS Population structure analysis grouped the ST217 isolates into five sequence clusters (SCs), which were highly associated with different geographical regions and showed limited intracontinental and intercontinental spread. The SCs showed lower than expected genomic sequence, which suggested strong purifying selection and small population sizes caused by bottlenecks. Recombination rates varied between the SCs but were lower than in other successful clones such as PMEN1. African isolates showed higher prevalence of antibiotic resistance genes than Asian isolates. Interestingly, certain West African isolates harbored a defective chloramphenicol and tetracycline resistance-conferring element (Tn5253) with a deletion in the loci encoding the chloramphenicol resistance gene (cat pC194), which caused lower chloramphenicol than tetracycline resistance. Furthermore, certain genes that promote colonisation were absent in the isolates, which may contribute to serotype 1's rarity in carriage and consequently its lower recombination rates. CONCLUSIONS The high phylogeographic diversity of the ST217 clone shows that this clone has been in circulation globally for a long time, which allowed its diversification and adaptation in different geographical regions. Such geographic adaptation reflects local variations in selection pressures in different locales. Further studies will be required to fully understand the biological mechanisms which makes the ST217 clone highly invasive but unable to successfully colonise the human nasopharynx for long durations which results in lower recombination rates.
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Affiliation(s)
- Chrispin Chaguza
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | - Jennifer E. Cornick
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | - Simon R. Harris
- Pathogen Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, CB10 1SA UK
| | - Cheryl P. Andam
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
- Department of Epidemiology, Center for Communicable Disease Dynamics, Harvard T. H. Chan School of Public Health, Massachusetts, MA 02115 USA
| | - Laura Bricio-Moreno
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
| | - Marie Yang
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
| | - Feyruz Yalcin
- Pathogen Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, CB10 1SA UK
| | - Sani Ousmane
- Unité de Biologie, Centre de Recherche Médicale et Sanitaire (CERMES), Niamey, Niger
| | - Shanil Govindpersad
- National Institute for Communicable Diseases (NICD), Johannesburg, South Africa
| | - Madikay Senghore
- Bacterial Diseases Programme, Medical Research Council (MRC), Banjul, The Gambia
- Division of Translational and Systems Medicine, Warwick Medical School, University of Warwick, Coventry, CV4 7AL UK
| | - Chinelo Ebruke
- Bacterial Diseases Programme, Medical Research Council (MRC), Banjul, The Gambia
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT UK
| | - Mignon Du Plessis
- National Institute for Communicable Diseases (NICD), Johannesburg, South Africa
| | - Anmol M. Kiran
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | - Gerd Pluschke
- Swiss Tropical and Public Health Institute, Basel, Switzerland
| | - Betuel Sigauque
- Centro de Investigação em Saúde da Manhiça, Maputo, Mozambique
| | - Lesley McGee
- Respiratory Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia GA 30329 USA
| | - Keith P. Klugman
- Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322 USA
- Bill and Melinda Gates Foundation, Seattle, WA 98109 USA
| | - Paul Turner
- Cambodia Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7FZ UK
| | - Jukka Corander
- Department of Mathematics and Statistics, University of Helsinki, Helsinki, Finland
| | - Julian Parkhill
- Pathogen Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, CB10 1SA UK
| | - Jean-Marc Collard
- Unité de Biologie, Centre de Recherche Médicale et Sanitaire (CERMES), Niamey, Niger
| | - Martin Antonio
- Bacterial Diseases Programme, Medical Research Council (MRC), Banjul, The Gambia
- Division of Translational and Systems Medicine, Warwick Medical School, University of Warwick, Coventry, CV4 7AL UK
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT UK
| | - Anne von Gottberg
- National Institute for Communicable Diseases (NICD), Johannesburg, South Africa
- School of Pathology, University of the Witwatersrand, Johannesburg, South Africa
| | - Robert S. Heyderman
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi
- Division of Infection and Immunity, University College London, London, WC1E 6BT UK
| | - Neil French
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | - Aras Kadioglu
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
| | - William P. Hanage
- Department of Epidemiology, Center for Communicable Disease Dynamics, Harvard T. H. Chan School of Public Health, Massachusetts, MA 02115 USA
| | - Dean B. Everett
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, Blantyre, Malawi
| | - Stephen D. Bentley
- Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L69 7BE UK
- Pathogen Genomics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, CB10 1SA UK
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Owusu E, Newman MJ, Akumwena A, Ofosu-Appiah L, Pluschke G. Maximizing microscopy as a diagnostic tool in peripheral health centres of BU endemic areas in Ghana. Int J Mycobacteriol 2016; 4:184-90. [PMID: 27649864 DOI: 10.1016/j.ijmyco.2015.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Accepted: 03/14/2015] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Buruli ulcer (BU) disease, a skin condition caused by Mycobacterium ulcerans (M. ulcerans) is endemic in remote rural areas. Disease diagnosis on clinical basis alone can be misleading, requiring definitive diagnosis based on laboratory tests. Resource constraints in BU endemic areas make microscopy for the detection of acid fast bacilli (AFB) an important and useful method. It is rapid, user-friendly, convenient and cheap. Despite its usefulness, its performance is relatively low. This study investigated modifications of the current method aimed at improving its performance. Forty (IS) 2404 polymerase chain reactions (PCR) positive BU samples were processed by eight physical (centrifugation and overnight sedimentation) and chemical (phenol ammonium sulphate and sodium hypochlorite) modifications of the current direct method. Assessments were based on standard AFB evaluation coupled with in house criteria; positivity (P), clarity and contrast (C) release of bacilli from specimen (R). Overall AFB positivity rate was 64% (409/640). Each protocol had 80 smears. The percentage positivity (P) for the conventional method was 58% (46/80) smears. The highest positivity rate of 57/80 (%) was by protocol 7 (5% phenol in 4% ammonium sulphate (PhAS) and concentrated by overnight gravitational sedimentation). The least positivity rate at 35% (28/80) was by protocol 1 (smears from direct application of swab tips). The differences in performance between the two chemical tested; 5% phenol in 4% ammonium sulphate (PhAS) and 3.5% NaHOCl was significant (p<0.05). The differences between the two physical methods were however not significant (p>0.05). This study concluded that BU samples treated with a solution of 5% phenol in 4% ammonium sulphate and concentrated by either centrifugation or overnight sedimentation is useful for maximizing AFB detection by bright field microscopy. This can be useful in rural health facilities with resource constraints.
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Affiliation(s)
- Enid Owusu
- School of Biomedical and Allied Health Sciences, University of Ghana, Ghana
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