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Colebunders R, Hadermann A, Njamnshi AK, Mmbando BP, Kamoen O, Siewe Fodjo JN. Onchocerciasis-associated epilepsy and biomarkers. PLoS Negl Trop Dis 2024; 18:e0011808. [PMID: 38722830 PMCID: PMC11081238 DOI: 10.1371/journal.pntd.0011808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 11/20/2023] [Indexed: 05/13/2024] Open
Affiliation(s)
| | - Amber Hadermann
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - Alfred K. Njamnshi
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon
- Neuroscience Lab, Faculty of Medicine & Biomedical Sciences, The University of Yaoundé I, Yaoundé, Cameroon
| | - Bruno P. Mmbando
- National Institute for medical Research, Tanga Research Centre, Tanga, Tanzania
| | - Olivia Kamoen
- Department of Neurology, Heilig Hart Ziekenhuis, Lier, Belgium
| | - Joseph Nelson Siewe Fodjo
- Global Health Institute, University of Antwerp, Antwerp, Belgium
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon
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Arndts K, Kegele J, Massarani AS, Ritter M, Wagner T, Pfarr K, Lämmer C, Dörmann P, Peisker H, Menche D, Al-Bahra M, Prazeres da Costa C, Schmutzhard E, Matuja W, Hoerauf A, Layland-Heni LE, Winkler AS. Epilepsy and nodding syndrome in association with an Onchocerca volvulus infection drive distinct immune profile patterns. PLoS Negl Trop Dis 2023; 17:e0011503. [PMID: 37535695 PMCID: PMC10426931 DOI: 10.1371/journal.pntd.0011503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 08/15/2023] [Accepted: 07/05/2023] [Indexed: 08/05/2023] Open
Abstract
Previous studies have described the association of onchocerciasis (caused by Onchocerca volvulus) with epilepsy, including nodding syndrome, although a clear etiological link is still missing. Cases are found in different African countries (Tanzania, South Sudan, Uganda, Democratic Republic of the Congo, Central African Republic and Cameroon). In our study we investigated immunological parameters (cytokine, chemokine, immunoglobulin levels) in individuals from the Mahenge area, Tanzania, presenting with either epilepsy or nodding syndrome with or without O. volvulus infection and compared them to O. volvulus negative individuals from the same endemic area lacking neurological disorders. Additionally, cell differentiation was performed using blood smears and systemic levels of neurodegeneration markers, leiomodin-1 and N-acetyltyramine-O, β-glucuronide (NATOG) were determined. Our findings revealed that cytokines, most chemokines and neurodegeneration markers were comparable between both groups presenting with epilepsy or nodding syndrome. However, we observed elevated eosinophil percentages within the O. volvulus positive epilepsy/nodding syndrome patients accompanied with increased eosinophilic cationic protein (ECP) and antigen-specific IgG levels in comparison to those without an O. volvulus infection. Furthermore, highest levels of NATOG were found in O. volvulus positive nodding syndrome patients. These findings highlight that the detection of distinct biomarkers might be useful for a differential diagnosis of epilepsy and nodding syndrome in O. volvulus endemic areas. Trial-registration: NCT03653975.
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Affiliation(s)
- Kathrin Arndts
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, German
| | - Josua Kegele
- Hertie Institute for Clinical Brain Research, Department of Neurology and Epileptology, University of Tübingen, Tübingen, Germany
| | - Alain S. Massarani
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, German
| | - Manuel Ritter
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, German
| | - Thomas Wagner
- Center for Pediatric and Adolescent Medicine, University Heidelberg, Heidelberg, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
- German Center for Infection Research (DZIF), Partner Site Munich, Germany
| | - Kenneth Pfarr
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, German
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Christine Lämmer
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, German
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Peter Dörmann
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, Bonn, Germany
| | - Helga Peisker
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, Bonn, Germany
| | - Dirk Menche
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Bonn, Germany
| | - Mazen Al-Bahra
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Bonn, Germany
| | - Clarissa Prazeres da Costa
- German Center for Infection Research (DZIF), Partner Site Munich, Germany
- Institute of Medical Microbiology, Immunology and Hygiene, Technical University of Munich, Munich, Germany
- Center for Global Health, School of Medicine, Technical University of Munich, Munich, Germany
| | - Erich Schmutzhard
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - William Matuja
- Department of Neurology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Achim Hoerauf
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, German
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
- German-West African Centre for Global Health and Pandemic Prevention (G-WAC), Partner Site Bonn, Bonn, Germany
| | - Laura E. Layland-Heni
- Institute of Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, German
- German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Andrea S. Winkler
- Center for Global Health, School of Medicine, Technical University of Munich, Munich, Germany
- Department of Neurology, Technical University of Munich, Munich, Germany
- Department of Community Medicine and Global Health, Institute of Health and Society, University of Oslo, Oslo, Norway
- Department of Global Health and Social Medicine, Harvard Medical School, Boston, Massachusetts, USA
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Rosa BA, Curtis K, Erdmann Gilmore P, Martin J, Zhang Q, Sprung R, Weil GJ, Townsend RR, Fischer PU, Mitreva M. Direct Proteomic Detection and Prioritization of 19 Onchocerciasis Biomarker Candidates in Humans. Mol Cell Proteomics 2022; 22:100454. [PMID: 36435333 PMCID: PMC9792368 DOI: 10.1016/j.mcpro.2022.100454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/30/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022] Open
Abstract
Onchocerca volvulus, the causative agent of onchocerciasis, infects over 20 million people and can cause severe dermatitis and ocular conditions including blindness. Current treatments employed in mass drug administration programs do not kill adult female worms, and common diagnostic tests cannot reliably assess viability of adult worms. There is an urgent need for better diagnostic tests to facilitate monitoring the efficacy of new treatments and disease elimination efforts. Here, eight plasma samples collected from individuals infected with O. volvulus and seven from uninfected individuals were analyzed by MS/MS spectrometry to directly identify O. volvulus proteins present in infected but absent in uninfected control samples. This direct proteomic approach for biomarker discovery had not been previously employed for onchocerciasis. Among all detected proteins, 19 biomarker candidates were supported by two or more unique peptides, identified in the plasma of at least three O. volvulus-infected human samples and absent in all control samples. Comprehensive analysis and ranking of these candidates included detailed functional annotation and a review of RNA-seq gene expression profiles. Isotope-labeled standard peptides were run in parallel and validated MS/MS peptide identifications for 15 peptides from 11 of the 19 proteins, and two infected urine and one uninfected urine sample was used for additional validation. A major antigen/OVOC11613 was identified as the most promising candidate with eight unique peptides across five plasma samples and one urine sample. Additional strong candidates included OVOC1523/ATP synthase, OVOC247/laminin and OVOC11626/PLK5, and along with OVOC11613, and were also detected in urine samples from onchocerciasis patients. This study has identified a promising novel set of proteins that will be carried forward to develop assays that can be used for diagnosis of O. volvulus infections and for monitoring treatment efficacy.
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Affiliation(s)
- Bruce A. Rosa
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - Kurt Curtis
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - Petra Erdmann Gilmore
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - John Martin
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - Qiang Zhang
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - Robert Sprung
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - Gary J. Weil
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - R. Reid Townsend
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - Peter U. Fischer
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - Makedonka Mitreva
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA,Department of Genetics, Washington University School of Medicine, St Louis, Missouri, USA,McDonnell Genome Institute, Washington University School of Medicine, St Louis, Missouri, USA,For correspondence: Makedonka Mitreva
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Lagatie O, Njumbe Ediage E, Van Roosbroeck D, Van Asten S, Verheyen A, Batsa Debrah L, Debrah A, Odiere MR, T’Kindt R, Dumont E, Sandra K, Dillen L, Verhaeghe T, Vreeken R, Cuyckens F, Stuyver LJ. Multimodal biomarker discovery for active Onchocerca volvulus infection. PLoS Negl Trop Dis 2021; 15:e0009999. [PMID: 34843471 PMCID: PMC8659328 DOI: 10.1371/journal.pntd.0009999] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/09/2021] [Accepted: 11/16/2021] [Indexed: 11/19/2022] Open
Abstract
The neglected tropical disease onchocerciasis, or river blindness, is caused by infection with the filarial nematode Onchocerca volvulus. Current estimates indicate that 17 million people are infected worldwide, the majority of them living in Africa. Today there are no non-invasive tests available that can detect ongoing infection, and that can be used for effective monitoring of elimination programs. In addition, to enable pharmacodynamic studies with novel macrofilaricide drug candidates, surrogate endpoints and efficacy biomarkers are needed but are non-existent. We describe the use of a multimodal untargeted mass spectrometry-based approach (metabolomics and lipidomics) to identify onchocerciasis-associated metabolites in urine and plasma, and of specific lipid features in plasma of infected individuals (O. volvulus infected cases: 68 individuals with palpable nodules; lymphatic filariasis cases: 8 individuals; non-endemic controls: 20 individuals). This work resulted in the identification of elevated concentrations of the plasma metabolites inosine and hypoxanthine as biomarkers for filarial infection, and of the urine metabolite cis-cinnamoylglycine (CCG) as biomarker for O. volvulus. During the targeted validation study, metabolite-specific cutoffs were determined (inosine: 34.2 ng/ml; hypoxanthine: 1380 ng/ml; CCG: 29.7 ng/ml) and sensitivity and specificity profiles were established. Subsequent evaluation of these biomarkers in a non-endemic population from a different geographical region invalidated the urine metabolite CCG as biomarker for O. volvulus. The plasma metabolites inosine and hypoxanthine were confirmed as biomarkers for filarial infection. With the availability of targeted LC-MS procedures, the full potential of these 2 biomarkers in macrofilaricide clinical trials, MDA efficacy surveys, and epidemiological transmission studies can be investigated. Today’s diagnosis of infection with the filarial parasite Onchocerca volvulus mainly depends on the microscopic analysis of skin biopsies and serological testing. The work presented here describes the use of multiple mass spectrometry-based screening methods (metabolomics and lipidomics) to search for biomarkers indicative of infection with Onchocerca volvulus. This resulted in the identification of elevated concentrations of the plasma metabolites inosine and hypoxanthine as biomarkers for filarial infection, and of the urine metabolite cis-cinnamoylglycine as biomarker for O. volvulus. Further evaluation of these biomarkers in a geographically distinct non-endemic population however invalidated the use of urine cis-cinnamoylglycine. These findings are of utmost importance as it not only opens new avenues in the development of non-invasive diagnostic tools for filarial infections, but also emphasizes the need for evaluation and validation of newly discovered biomarkers in different populations from different geographies.
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Affiliation(s)
- Ole Lagatie
- J&J Global Public Health, Janssen R&D, Beerse, Belgium
- * E-mail:
| | | | | | | | - Ann Verheyen
- J&J Global Public Health, Janssen R&D, Beerse, Belgium
| | - Linda Batsa Debrah
- Department of Clinical Microbiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Alex Debrah
- Faculty of Allied Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Maurice R. Odiere
- Kenya Medical Research Institute, Centre for Global Health Research, Kisumu, Kenya
| | - Ruben T’Kindt
- Research Institute for Chromatography (RIC), Kortrijk, Belgium
| | - Emmie Dumont
- Research Institute for Chromatography (RIC), Kortrijk, Belgium
| | - Koen Sandra
- Research Institute for Chromatography (RIC), Kortrijk, Belgium
| | - Lieve Dillen
- Discovery Sciences, Janssen R&D, Beerse, Belgium
| | | | - Rob Vreeken
- Discovery Sciences, Janssen R&D, Beerse, Belgium
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Urine metabolites for the identification of Onchocerca volvulus infections in patients from Cameroon. Parasit Vectors 2021; 14:397. [PMID: 34380554 PMCID: PMC8359580 DOI: 10.1186/s13071-021-04893-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/24/2021] [Indexed: 11/10/2022] Open
Abstract
Background The tropical disease onchocerciasis (river blindness), caused by Onchocerca volvulus filarial nematodes, is targeted for elimination by mass treatment with nematocidal and antimicrobial drugs. Diagnosis of O. volvulus infections is based on counts of skin-borne microfilariae, but additional diagnostic tools, e.g. worm- or host-derived small RNAs, proteins or metabolites, are required for high-throughput screening. N-acetyltyramine-O,β-glucuronide (NATOG) was suggested as a biomarker for onchocerciasis but its viability as diagnostic tool has been challenged. Methods We performed a screening program of urine samples from individuals from Cameroon infected with O. volvulus, Loa loa, Mansonella perstans or a combination thereof. Urine metabolites were measured by liquid chromatography–mass spectrometry (LC-MS). Principle component analysis (PCA) revealed that onchocerciasis causes complex changes of the urine metabolome. Results The mean NATOG content was elevated in urine of O. volvulus-infected compared with non-infected individuals, but NATOG levels showed considerable variation. However, 13.8% of all O. volvulus-infected individuals had high NATOG levels never reached by individuals without filarial infections or only infected with L. loa or M. perstans. Therefore, the identification of individuals with high NATOG levels might be used to screen for the elimination of onchocerciasis after mass drug application. Additional metabolites, including a compound identified as cinnamoylglycine, had high PC1/PC2 loadings in the data set. Mean levels of cinnamoylglycine were increased in O. volvulus-infected individuals, and 17.2% of all O. volvulus individuals had elevated cinnamoylglycine levels not reached by the controls. Conclusions On an individual level, NATOG alone had poor discriminative power distinguishing infected from non-infected individuals. However, 13.8% of all O. volvulus-infected individuals had NATOG levels never reached by individuals without filarial infections or infected with only L. loa or M. perstans. Discrimination of O. volvulus infections from controls or individuals suffering from multiple infections was improved by the measurement of additional metabolites, e.g. cinnamoylglycine. Thus, measuring a combination of urine metabolites may provide a way to assess onchocerciasis on the population level. This provides the possibility to design a strategy for large-scale onchocerciasis epidemiological screening programs based on urine rather than invasive techniques. Graphical abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13071-021-04893-1.
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Vieri MK, Hotterbeekx A, Raimon S, Abd-Elfarag G, Mukendi D, Carter JY, Kumar-Singh S, Colebunders R. Cytokines and Onchocerciasis-Associated Epilepsy, a Pilot Study and Review of the Literature. Pathogens 2021; 10:310. [PMID: 33799934 PMCID: PMC7998365 DOI: 10.3390/pathogens10030310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/04/2021] [Accepted: 03/05/2021] [Indexed: 12/03/2022] Open
Abstract
Neuro-inflammation may be associated with onchocerciasis-associated epilepsy (OAE) but thus far very few immunological studies have been performed in children with this form of epilepsy. In a pilot study we measured the cytokine levels in cerebrospinal fluid (CSF) of persons with OAE from Maridi, South Sudan, and from Mosango, Democratic Republic of the Congo (DRC) and compared these results with cytokine levels in CSF of Africans with non-OAE neurological disorders, and Europeans with epilepsy or other neurological conditions. The following cytokines were studied: IL-6, TNF-α, IL1-β, IL-5, IL-4, IL-13, CCL3 (Mip-1α), VEGF-C, VCAM-1. No cytokine was significantly associated with OAE, although a lower IL-13 level was observed in CSF of persons with OAE compared to African controls. Observed cytokine profiles and neuro-inflammation may be the consequence of long-standing epilepsy, concomitant infections and malnutrition. Ideally cytokine levels should be determined in a prospective study in serum and CSF collected at the time of onset of the first seizures.
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Affiliation(s)
| | - An Hotterbeekx
- Global Health Institute, University of Antwerp, 2610 Antwerp, Belgium;
- Molecular Pathology Group, Laboratory of Cell Biology & Histology, Faculty of Medical and Health Sciences, University of Antwerp, 20610 Antwerp, Belgium;
| | | | - Gasim Abd-Elfarag
- Academic Medical Center, Global Child Health Group, Department of Paediatrics and Department of Global Health, University of Amsterdam, 1105 Amsterdam, The Netherlands;
- Amsterdam Institute for Global Health and Development, 1105 Amsterdam, The Netherlands
| | - Deby Mukendi
- Institut National de Recherche Biomédicale, Av. De la Démocratie N°5345, Kinshasa 1197, Congo;
- Centre Neuro-Psycho Pathologique, Universite’ de Kinshasa, Kinshasa P.O. Box 127, Congo
| | - Jane Y. Carter
- Amref International Headquarters, Nairobi P.O. Box 27691−00506, Kenya;
| | - Samir Kumar-Singh
- Molecular Pathology Group, Laboratory of Cell Biology & Histology, Faculty of Medical and Health Sciences, University of Antwerp, 20610 Antwerp, Belgium;
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Colebunders R, Njamnshi AK, Menon S, Newton CR, Hotterbeekx A, Preux PM, Hopkins A, Vaillant M, Siewe Fodjo JN. Onchocerca volvulus and epilepsy: A comprehensive review using the Bradford Hill criteria for causation. PLoS Negl Trop Dis 2021; 15:e0008965. [PMID: 33411705 PMCID: PMC7790236 DOI: 10.1371/journal.pntd.0008965] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND The possibility that onchocerciasis may cause epilepsy has been suggested for a long time, but thus far, an etiological link has not been universally accepted. The objective of this review is to critically appraise the relationship between Onchocerca volvulus and epilepsy and subsequently apply the Bradford Hill criteria to further evaluate the likelihood of a causal association. METHODS PubMed and gray literature published until September 15, 2020, were searched and findings from original research were synthesized. Adherence to the 9 Bradford Hill criteria in the context of onchocerciasis and epilepsy was determined to assess whether the criteria are met to strengthen the evidence base for a causal link between infection with O. volvulus and epilepsy, including the nodding syndrome. RESULTS Onchocerciasis as a risk factor for epilepsy meets the following Bradford Hill criteria for causality: strength of the association, consistency, temporality, and biological gradient. There is weaker evidence supporting causality based on the specificity, plausibility, coherence, and analogy criteria. There is little experimental evidence. Considering the Bradford Hill criteria, available data suggest that under certain conditions (high microfilarial load, timing of infection, and perhaps genetic predisposition), onchocerciasis is likely to cause epilepsy including nodding and Nakalanga syndromes. CONCLUSION Applying the Bradford Hill criteria suggests consistent epidemiological evidence that O. volvulus infection is a trigger of epilepsy. However, the pathophysiological mechanisms responsible for seizure induction still need to be elucidated.
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Affiliation(s)
- Robert Colebunders
- Global Health Institute, University of Antwerp, Antwerp, Belgium
- * E-mail:
| | - Alfred K. Njamnshi
- Neurology Department, Yaoundé Central Hospital, Yaoundé, Cameroon
- Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé Cameroon
- Brain Research Africa Initiative (BRAIN), Yaoundé, Cameroon
| | - Sonia Menon
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - Charles R. Newton
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - An Hotterbeekx
- Global Health Institute, University of Antwerp, Antwerp, Belgium
| | - Pierre-Marie Preux
- Institute of Epidemiology and Tropical Neurology, INSERM UMR1094, University of Limoges, Limoges, France
| | - Adrian Hopkins
- Neglected and Disabling Diseases of Poverty Consultant, Kent, United Kingdom
| | - Michel Vaillant
- Competence Center in Methodology and Statistics, Luxembourg Institute of Health, Strassen, Luxembourg
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