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Idro R, Ogwang R, Anguzu R, Akun P, Ningwa A, Abbo C, Giannoccaro MP, Kubofcik J, Mwaka AD, Nakamya P, Opar B, Taylor M, Nutman TB, Elliott A, Vincent A, Newton CR, Marsh K. Doxycycline for the treatment of nodding syndrome: a randomised, placebo-controlled, phase 2 trial. Lancet Glob Health 2024; 12:e1149-e1158. [PMID: 38754459 PMCID: PMC11191365 DOI: 10.1016/s2214-109x(24)00102-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 02/15/2024] [Accepted: 03/04/2024] [Indexed: 05/18/2024]
Abstract
BACKGROUND Nodding syndrome is a poorly understood neurological disorder that predominantly occurs in Africa. We hypothesised that nodding syndrome is a neuroinflammatory disorder, induced by antibodies to Onchocerca volvulus or its Wolbachia symbiont, cross-reacting with host neuronal proteins (HNPs), and that doxycycline can be used as treatment. METHODS In this randomised, double-blind, placebo-controlled, phase 2 trial, we recruited participants from districts affected by nodding syndrome in northern Uganda. We included children and adolescents aged 8-18 years with nodding syndrome, as defined by WHO consensus criteria. Participants were randomly assigned (1:1) to receive either 100 mg doxycycline daily or placebo for 6 weeks via a computer-generated schedule stratified by skin microscopy results, and all parties were masked to group assignment. Diagnoses of O volvulus and antibodies to HNPs were made using luciferase immunoprecipitation system assays and immunohistochemistry. The primary outcome was change in the proportion with antibodies to HNPs, assessed at 24 months. All participants were included in safety analyses, and surviving participants (those with samples at 24 months) were included in primary analyses. Secondary outcomes were: change in concentrations of antibodies to HNPs at 24 months compared with baseline; proportion of participants testing positive for antibodies to O volvulus-specific proteins and concentrations of Ov16 or OVOC3261 antibodies at 24 months compared with baseline; change in seizure burden, proportion achieving seizure freedom, and the proportions with interictal epileptiform discharges on the diagnostic EEG; overall quality of life; disease severity at 24 months; and incidence of all-cause adverse events, serious adverse events, and seizure-related mortality by 24 months. This trial is registered with ClinicalTrials.gov, NCT02850913. FINDINGS Between Sept 1, 2016, and Aug 31, 2018, 329 children and adolescents were screened, of whom 240 were included in the study. 140 (58%) participants were boys and 100 (42%) were girls. 120 (50%) participants were allocated to receive doxycycline and 120 (50%) to receive placebo. At recruitment, the median duration of symptoms was 9 years (IQR 6-10); 232 (97%) participants had O volvulus-specific antibodies and 157 (65%) had autoantibodies to HNPs. The most common plasma autoantibodies were to human protein deglycase DJ-1 (85 [35%] participants) and leiomodin-1 (77 [32%] participants) and, in cerebrospinal fluid (CSF), to human DJ-1 (27 [11%] participants) and leiomodin-1 (14 [6%] participants). On immunohistochemistry, 46 (19%) participants had CSF autoantibodies to HNPs, including leiomodin-1 (26 [11%]), γ-aminobutyric acid B receptors (two [<1%]), CASPR2 (one [<1%]), or unknown targets (28 [12%]). At 24 months, 161 (72%) of 225 participants had antibodies to HNPs compared with 157 (65%) of 240 at baseline. 6 weeks of doxycycline did not affect the concentration of autoantibodies to HNPs, seizure control, disease severity, or quality of life at the 24-month follow-up but substantially decreased Ov16 antibody concentrations; the median plasma signal-to-noise Ov16 ratio was 16·4 (95% CI 6·4-38·4), compared with 27·9 (8·2-65·8; p=0·033) for placebo. 14 (6%) participants died and, other than one traffic death, all deaths were seizure-related. Acute seizure-related hospitalisations (rate ratio [RR] 0·43 [95% CI 0·20-0·94], p=0·028) and deaths (RR 0·46 [0·24-0·89], p=0·028) were significantly lower in the doxycycline group. At 24 months, 96 (84%) of 114 participants who received doxycycline tested positive for antibodies to Ov16, compared with 97 (87%) of 111 on placebo (p=0·50), and 74 (65%) participants on doxycycline tested positive for antibodies to OVOC3261, compared with 57 (51%) on placebo (p=0·039). Doxycycline was safe; there was no difference in the incidence of grade 3-5 adverse events across the two groups. INTERPRETATION Nodding syndrome is strongly associated with O volvulus and the pathogenesis is probably mediated through an O volvulus induced autoantibody response to multiple proteins. Although it did not reverse disease symptoms, doxycycline or another prophylactic antibiotic could be considered as adjunct therapy to antiseizure medication, as it might reduce fatal complications from acute seizures and status epilepticus induced by febrile infections. FUNDING Medical Research Council (UK). TRANSLATION For the Luo translation of the abstract see Supplementary Materials section.
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Affiliation(s)
- Richard Idro
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda; Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK.
| | - Rodney Ogwang
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda
| | - Ronald Anguzu
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda
| | - Pamela Akun
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda
| | - Albert Ningwa
- College of Health Sciences, Makerere University, Kampala, Uganda; Centre for Tropical Neuroscience, Kampala, Uganda
| | - Catherine Abbo
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Maria P Giannoccaro
- Istituto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica, Bologna, Italy
| | - Joseph Kubofcik
- Laboratory of Parasitic Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Amos D Mwaka
- College of Health Sciences, Makerere University, Kampala, Uganda
| | | | | | - Mark Taylor
- Centre for Neglected Tropical Diseases, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Thomas B Nutman
- Laboratory of Parasitic Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Alison Elliott
- Medical Research Council/Uganda Virus Research Institute and London School of Hygiene & Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Charles R Newton
- Department of Psychiatry, Warneford Hospital, University of Oxford, Oxford, UK
| | - Kevin Marsh
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
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Pietrzak D, Łuczak JW, Wiśniewski M. Beyond Tradition: Exploring Cutting-Edge Approaches for Accurate Diagnosis of Human Filariasis. Pathogens 2024; 13:447. [PMID: 38921745 PMCID: PMC11206659 DOI: 10.3390/pathogens13060447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 05/16/2024] [Accepted: 05/23/2024] [Indexed: 06/27/2024] Open
Abstract
Filariasis is recognised as a global public health threat, particularly in tropical and subtropical regions. It is caused by infection with a nematode parasite of the superfamily Filarioidea, including Wuchereria bancrofti, Brugia malayi, Onchocerca volvulus, and Onchocerca lupi. Three main types of filariasis have been classified: lymphatic filariasis, subcutaneous filariasis, and serous cavity filariasis. The symptoms exhibited by individuals afflicted with filariasis are diverse and contingent upon several variables, including the species of parasite, the host's health and immune response, and the stage of infection. While many classical parasitological techniques are considered indispensable tools for the diagnosis of parasitic infections in humans, alternative methods are being sought due to their limitations. Novel tests based on host-parasite interactions offer a rapid, simple, sensitive, and specific diagnostic tool in comparison to traditional parasitological methods. This article presents methods developed in the 21st century for the diagnosis of filariasis caused by invasion from W. bancrofti, B. malayi, O. volvulus, and O. lupi, as well as techniques that are currently in use. The development of modern diagnostic methods based on molecular biology constitutes a significant advancement in the fight against filariasis.
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Affiliation(s)
- Damian Pietrzak
- Division of Parasitology and Parasitic Diseases, Department of Preclinical Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences—SGGW, 02-786 Warsaw, Poland;
| | - Julia Weronika Łuczak
- Faculty of Animal Breeding, Bioengineering and Conservation, Warsaw University of Life Sciences—SGGW, 02-786 Warsaw, Poland;
| | - Marcin Wiśniewski
- Division of Parasitology and Parasitic Diseases, Department of Preclinical Sciences, Institute of Veterinary Medicine, Warsaw University of Life Sciences—SGGW, 02-786 Warsaw, Poland;
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Ambe LA, Limunga E, Mbah CE, Adela N, Eric N, Ngoe M, Sone B, Lochnit G, Tachu JB, Wanji S, Taubert A, Hermosilla C, Kamena F. Identification and Characterization of Onchocerca volvulus Heat Shock Protein 70 ( OvHSP70) as Novel Diagnostic Marker of Onchocerciasis in Human Urine. Pathogens 2024; 13:293. [PMID: 38668248 PMCID: PMC11053476 DOI: 10.3390/pathogens13040293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 03/07/2024] [Accepted: 03/11/2024] [Indexed: 04/29/2024] Open
Abstract
Despite several decades of mass drug administration and elimination-related activities, human onchocerciasis still represents a major parasitic threat in endemic regions. Among the challenges encountered by the elimination program is the lack of a suitable diagnostic tool that is accurate and non-invasive. Currently used methods are either invasive or not suitable for monitoring large numbers of patients. Herein, we describe the identification and characterization of Onchocerca volvulus heat shock protein 70 (OvHSP70) as a novel diagnostic biomarker for human onchocerciasis, which can directly be detected in urine samples of infected patients. This nematode-specific antigen was identified through LC-MS after differential SDS-PAGE using urine-derived protein extracts from O. volvulus-infected patients in Cameroon. Polyclonal antibodies generated in rabbits after cloning and expression of OvHSP70 in Escherichia coli reliably differentiated between urine samples from infected- and uninfected patients in a hypoendemic area of human onchocerciasis. These results provide an excellent basis for further development of a non-invasive and scalable diagnostic assay for human onchocerciasis using urine samples. Such a urine-based diagnostic assay will be of major importance for the elimination program of human onchcerciasis in endemic countries.
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Affiliation(s)
- Lum Abienwi Ambe
- Laboratory for Molecular Parasitology, Department of Microbiology and Parasitology, University of Buea, Buea P.O. Box 63, Cameroon; (E.L.); (N.E.); (M.N.); (B.S.); (J.B.T.)
- Centre for Research on Health and Priority Pathologies, Institute of Medical Research and Medicinal Plants Studies (IMPM), Yaounde P.O. Box 13033, Cameroon; (C.E.M.); (N.A.)
| | - Elisabeth Limunga
- Laboratory for Molecular Parasitology, Department of Microbiology and Parasitology, University of Buea, Buea P.O. Box 63, Cameroon; (E.L.); (N.E.); (M.N.); (B.S.); (J.B.T.)
| | - Clarisse Engowei Mbah
- Centre for Research on Health and Priority Pathologies, Institute of Medical Research and Medicinal Plants Studies (IMPM), Yaounde P.O. Box 13033, Cameroon; (C.E.M.); (N.A.)
| | - Ngwewondo Adela
- Centre for Research on Health and Priority Pathologies, Institute of Medical Research and Medicinal Plants Studies (IMPM), Yaounde P.O. Box 13033, Cameroon; (C.E.M.); (N.A.)
| | - Ndumu Eric
- Laboratory for Molecular Parasitology, Department of Microbiology and Parasitology, University of Buea, Buea P.O. Box 63, Cameroon; (E.L.); (N.E.); (M.N.); (B.S.); (J.B.T.)
| | - Martha Ngoe
- Laboratory for Molecular Parasitology, Department of Microbiology and Parasitology, University of Buea, Buea P.O. Box 63, Cameroon; (E.L.); (N.E.); (M.N.); (B.S.); (J.B.T.)
| | - Bertrand Sone
- Laboratory for Molecular Parasitology, Department of Microbiology and Parasitology, University of Buea, Buea P.O. Box 63, Cameroon; (E.L.); (N.E.); (M.N.); (B.S.); (J.B.T.)
| | - Günter Lochnit
- Protein Analytics, Institute of Biochemistry, Faculty of Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany;
| | - Julius Babila Tachu
- Laboratory for Molecular Parasitology, Department of Microbiology and Parasitology, University of Buea, Buea P.O. Box 63, Cameroon; (E.L.); (N.E.); (M.N.); (B.S.); (J.B.T.)
| | - Samuel Wanji
- Department of Microbiology and Parasitology, Faculty of Science, University of Buea, Buea P.O. Box 63, Cameroon;
- Research Foundation in Tropical Disease and Environment (REFOTDE), Buea P.O. Box 474, Cameroon
| | - Anja Taubert
- Biomedical Research Center Seltersberg (BFS), Institute of Parasitology, Justus Liebig University Giessen, 35392 Giessen, Germany; (A.T.); (C.H.)
| | - Carlos Hermosilla
- Biomedical Research Center Seltersberg (BFS), Institute of Parasitology, Justus Liebig University Giessen, 35392 Giessen, Germany; (A.T.); (C.H.)
| | - Faustin Kamena
- Laboratory for Molecular Parasitology, Department of Microbiology and Parasitology, University of Buea, Buea P.O. Box 63, Cameroon; (E.L.); (N.E.); (M.N.); (B.S.); (J.B.T.)
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Mazumder R, Lubowa SK, Salamon N, Jackson NJ, Kawooya M, Akun PR, Anguzu R, Ogwang RJ, Kubofcik J, Nutman T, Marsh K, Newton C, Vincent A, Idro R. Comparison of Structural Changes in Nodding Syndrome and Other Epilepsies Associated With Onchocerca volvulus. NEUROLOGY(R) NEUROIMMUNOLOGY & NEUROINFLAMMATION 2022; 10:10/2/e200074. [PMID: 36543539 PMCID: PMC9773419 DOI: 10.1212/nxi.0000000000200074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 10/18/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND AND OBJECTIVE Nodding syndrome (NS) is a unique childhood-onset epileptic disorder that occurs predominantly in several regions of sub-Saharan Africa. The disease has been associated with Onchocerca volvulus (Ov)-induced immune responses and possible cross-reactivity with host proteins. The aim of this study was to compare structural changes in the brain on MRI between NS and other forms of onchocerciasis-associated epilepsies (OAEs) and to relate structural changes to the Ov-induced immune responses and level of disability. METHODS Thirty-nine children with NS and 14 age-matched participants with other forms of OAE from an endemic region in Uganda underwent detailed clinical examination, serologic evaluation (including Ov-associated antibodies to Ov-16 and Hu-leiomodin-1) and quantitative volumetric analysis of brain MRIs (1.5 T scanner) using Neuroreader, a cloud-based software. RESULTS Cerebral and cerebellar atrophy were the predominant features in both NS and OAE. On quantitative volumetric analysis, participants with NS had larger ventricular volumes compared with participants with OAE, indicative of increased global cortical atrophy (pcorr = 0.036). Among children with NS, severe disability correlated with higher degree of atrophy in the gray matter volume (pcorr = 0.009) and cerebellar volume (pcorr = 0.009). NS cases had lower anti-Ov-16 IgG signal-to-noise ratios than the OAE cases (p < 0.01), but no difference in the levels of the Hu-leiomodin-1 antibodies (p = 0.64). The levels of Ov-associated antibodies did not relate to the degree of cerebral or cerebellar atrophy in either NS or OAE cases. DISCUSSION This is the first study to show that cerebral and cerebellar atrophy correlated with the severity of NS disability, providing an imaging marker for these endemic epileptic disorders that until now have remained poorly characterized. Both NS and OAE have cerebral and cerebellar atrophy, and the levels of Ov-associated antibodies do not seem to be related to the structural changes on MRI.
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Affiliation(s)
- Rajarshi Mazumder
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Samson Kamya Lubowa
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Noriko Salamon
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Nicholas J Jackson
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Michael Kawooya
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Pamela Rosemary Akun
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Ronald Anguzu
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Rodney J Ogwang
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Joseph Kubofcik
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Thomas Nutman
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Kevin Marsh
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Charles Newton
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Angela Vincent
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom
| | - Richard Idro
- From the Department of Neurology (R.M.), David Geffen School of Medicine at University of California Los Angeles; Kampala MRI Centre (S.K.L., M.K.), Uganda; Department of Radiological Sciences (N.S.), David Geffen School of Medicine, University of California Los Angeles, CA; Division of General Internal Medicine and Health Services Research (N.J.J.), David Geffen School of Medicine at UCLA; Centre of Tropical Neuroscience (P.R.A., R.A., R.I.), Kitgum Site, Uganda; Makerere University (R.A., R.J.O., R.I.), College of Health Sciences, Kampala, Uganda; Laboratory of Parasitic Diseases (J.K., T.N.), National Institutes of Health, Bethesda, MD; Centre for Tropical Medicine and Global Health (K.M., R.I.), Nuffield Department of Medicine, University of Oxford, United Kingdom; Department of Psychiatry (C.N.), University of Oxford, United Kingdom; and Nuffield Department of Clinical Neurosciences (A.V.), University of Oxford, United Kingdom.
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5
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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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6
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Frallonardo L, Di Gennaro F, Panico GG, Novara R, Pallara E, Cotugno S, Guido G, De Vita E, Ricciardi A, Totaro V, Camporeale M, De Iaco G, Bavaro DF, Lattanzio R, Patti G, Brindicci G, Papagni R, Pellegrino C, Santoro CR, Segala FV, Putoto G, Nicastri E, Saracino A. Onchocerciasis: Current knowledge and future goals. FRONTIERS IN TROPICAL DISEASES 2022. [DOI: 10.3389/fitd.2022.986884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human Onchocerciasis, caused by infection by the filarial nematode Onchocerca volvulus, is a neglected public health disease that affects millions of people in the endemic regions of sub-Saharan Africa and Latin America. It is also called river blindness because the Blackflies that transmit infection breeds in rapidly flowing fresh water streams and rivers. This review features state-of-the-art data on the parasite, its endobacteria Wolbachia, the prevalence of the infection and its geographical distribution, its diagnostics, the interaction between the parasite and its host, and the pathology of Onchocerciasis. By development and optimization of the control measures, transmission by the vector has been interrupted in foci of countries in the Americas (Colombia, Ecuador, Mexico, and Guatemala)and inSudan, followed by Onchocerciasis eliminations. The current state and future perspectives for vector control and elimination strategy are described.
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7
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Adu Mensah D, Debrah LB, Gyamfi PA, Rahamani AA, Opoku VS, Boateng J, Obeng P, Osei-Mensah J, Kroidl I, Klarmann-Schulz U, Hoerauf A, Debrah AY. Occurrence of Lymphatic Filariasis infection after 15 years of mass drug administration in two hotspot districts in the Upper East Region of Ghana. PLoS Negl Trop Dis 2022; 16:e0010129. [PMID: 35926012 PMCID: PMC9380951 DOI: 10.1371/journal.pntd.0010129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 08/16/2022] [Accepted: 07/14/2022] [Indexed: 11/30/2022] Open
Abstract
Background Lymphatic filariasis (LF) causes chronic morbidity, which usually manifests as lymphedema or hydrocele. Mass drug administration (MDA) began in Kassena Nankana East Municipal (KNEM) and Nabdam, two hotspot districts in the Upper East Region in Ghana, in 2000 and 2005, respectively. This cross-sectional study evaluated the impact of 15 years of MDA on the control of LF as determined by circulating filarial antigen (CFA) and microfilariae assessment in the KNEM and the Nabdam districts. Methodology/Principal findings A total of 7,453 participants from eight sub-districts in the two hotspot districts (KNEM: N = 4604; Nabdam: N = 2849) were recruited into the study. The overall CFA prevalence as determined by the FTS was 19.6% and 12.8% in the KNEM and Nabdam districts, respectively. Manyoro, a sub-district on the border with Burkina Faso, recorded the highest CFA prevalence of 26% in the KNEM. Assessment of microfilariae and Og4C3 antigen was done from 1009 (KNEM: N = 799 (79.2%); Nabdam: N = 210 (20.8%)) randomly selected FTS-positive (N = 885) and FTS-negative (N = 124) individuals. The Og4C3 antigen was found in 22.6%/23.0% of the selected individuals (KNEM/Nabdam), whereas the night blood revealed microfilariae in only 0.7%/0.5%. Conclusions/Significance Using the WHO endorsed FTS, CFA prevalence exceeded the long-standing <2% threshold—which may need revision and validation. Surprisingly, the Og4C3 ELISA showed positive results in only about one-fifth of the FTS positive samples. However, even this result would not have met the <2% CFA criteria for LF elimination. In contrast, projections from the microfilariae results revealed a halt in LF transmission. The global elimination target was due in 2020 but has been extended to 2030 since this could not be met. Focused MDA intervention intensification on seasonal migrants and non-compliers, and implementation of alternative treatment strategies may suffice for the elimination of the disease. Lymphatic filariasis (LF) is a major neglected tropical disease (NTD) affecting over 120 million individuals worldwide and identified as one of WHO’s 20 NTDs targeted for elimination. It has strong links with poverty and is associated with significant clinical morbidity, which impose considerable socio-psychological and economic burdens on the affected individuals. One of the main goals of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) is the use of mass drug administration (MDA) to interrupt LF transmission. The initial 2020 elimination target year set by the GPELF could not be met, with 2030 now the new proposed year targeted for global elimination. The study evaluated the impact of 15 years of MDA on the control of LF in two hotspot districts in Ghana. The results from this study are indicative of a halt in LF transmission in the districts, with microfilaria detected in <1% of those sampled. However, the antigenemia prevalence is still above the recommended level. MDA should be intensified especially at the border towns or alternative treatment strategies should be employed to finally eliminate the disease as some people who are still with the active infection can serve as a reservoir for recrudescence and transmission in already “LF-free” areas.
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Affiliation(s)
- Derrick Adu Mensah
- Department of Clinical Microbiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Linda Batsa Debrah
- Department of Clinical Microbiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Peter Akosah Gyamfi
- Department of Clinical Microbiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- Faculty of Health Sciences, Garden City University College, Kumasi, Ghana
| | - Abu Abudu Rahamani
- Department of Clinical Microbiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Vera Serwaa Opoku
- Department of Clinical Microbiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - John Boateng
- Department of Clinical Microbiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Prince Obeng
- Department of Clinical Microbiology, School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Jubin Osei-Mensah
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Inge Kroidl
- Division of Infectious Diseases and Tropical Medicine, Medical Center of the University of Munich (LMU), Munich, Germany
- German Center for Infection Research (DZIF), Munich, Germany
| | - Ute Klarmann-Schulz
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Bonn-Cologne, Germany
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Bonn, Germany
- German Center for Infection Research (DZIF), Bonn-Cologne, Germany
| | - Alexander Yaw Debrah
- Faculty of Allied Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
- * E-mail:
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8
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Johanns SI, Gantin RG, Wangala B, Komlan K, Halatoko WA, Banla M, Karabou P, Luty AJF, Schulz-Key H, Köhler C, Soboslay PT. Onchocerca volvulus-specific antibody and cellular responses in onchocerciasis patients treated annually with ivermectin for 30 years and exposed to parasite transmission in central Togo. PLoS Negl Trop Dis 2022; 16:e0010340. [PMID: 35503786 PMCID: PMC9064110 DOI: 10.1371/journal.pntd.0010340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 03/20/2022] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Annual mass drug administrations (MDA) of ivermectin will strongly reduce Onchocerca volvulus microfilariae (mf) in the skin and in the onchocerciasis patients' eyes. Ivermectin treatment will also affect the expression of immunity in patients, such that activated immune defenses may help control and contribute to clearance of mf of O. volvulus. Longitudinal surveys are a prerequisite to determining the impact of ivermectin on the status of anti-parasite immunity, notably in risk zones where parasite transmission and active O. volvulus infections persist. METHODOLOGY/PRINCIPAL FINDINGS Onchocerciasis patients were treated annually with ivermectin and their Onchocerca volvulus antigen (OvAg) specific IgG and cellular responses were investigated before and at 30 years post initial ivermectin treatment (30yPT). Repeated annual ivermectin treatments eliminated persisting O. volvulus microfilariae (mf) from the skin of patients and abrogated patent infections. The OvAg-specific IgG1 and IgG4 responses were diminished at 30yPT to the levels observed in endemic controls. Prior to starting ivermectin treatment, OvAg-induced cellular productions of IL-10, IFN-γ, CCL13, CCL17 and CCL18 were low in patients, and at 30yPT, cellular cytokine and chemokine responses increased to the levels observed in endemic controls. In contrast, mitogen(PHA)- induced IL-10, IFN-γ, CCL17 and CCL18 cellular production was diminished. This divergent response profile thus revealed increased parasite antigen-specific but reduced polyclonal cellular responsiveness in patients. The transmission of O. volvulus continued at the patients' location in the Mô river basin in central Togo 2018 and 2019 when 0.58% and 0.45%, respectively, of Simulium damnosum s.l. vector blackflies carried O. volvulus infections. CONCLUSIONS/SIGNIFICANCE Repeated annual ivermectin treatment of onchocerciasis patients durably inhibited their patent O. volvulus infections despite ongoing low-level parasite transmission in the study area. Repeated MDA with ivermectin affects the expression of immunity in patients. O. volvulus parasite-specific antibody levels diminished to levels seen in infection-free endemic controls. With low antibody levels, antibody-dependent cellular cytotoxic responses against tissue-dwelling O. volvulus larvae will weaken. O. volvulus antigen inducible cytokine and chemokine production increased in treated mf-negative patients, while their innate responsiveness to mitogen declined. Such lower innate responsiveness in elderly patients could contribute to reduced adaptive immune responses to parasite infections and vaccines. On the other hand, increased specific cellular chemokine responses in mf-negative onchocerciasis patients could reflect effector cell activation against tissue invasive larval stages of O. volvulus. The annual Simulium damnosum s.l. biting rate observed in the Mô river basin was similar to levels prior to initiation of MDA with ivermectin, and the positive rtPCR results reported here confirm ongoing O. volvulus transmission.
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Affiliation(s)
- Saskia I. Johanns
- University Clinics Tübingen, Institute for Tropical Medicine, Eberhard-Karls University, Tübingen, Germany
| | - Richard G. Gantin
- Onchocerciasis Reference Laboratory, Institut National d’Hygiene, Centre Hospitalier Regional, Sokode, Togo
| | - Bawoubadi Wangala
- Onchocerciasis Reference Laboratory, Institut National d’Hygiene, Centre Hospitalier Regional, Sokode, Togo
| | | | | | - Meba Banla
- Centre Hospitalier Universitaire, Université de Lomé, Lomé, Togo
| | | | - Adrian JF Luty
- Université de Paris, Institut de Recherche pour le Développement, Paris, France
| | - Hartwig Schulz-Key
- University Clinics Tübingen, Institute for Tropical Medicine, Eberhard-Karls University, Tübingen, Germany
| | - Carsten Köhler
- University Clinics Tübingen, Institute for Tropical Medicine, Eberhard-Karls University, Tübingen, Germany
| | - Peter T. Soboslay
- University Clinics Tübingen, Institute for Tropical Medicine, Eberhard-Karls University, Tübingen, Germany
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9
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Ndondo AP, Eley B, Wilmshurst JM, Kakooza-Mwesige A, Giannoccaro MP, Willison HJ, Cruz PMR, Heckmann JM, Bateman K, Vincent A. Post-Infectious Autoimmunity in the Central (CNS) and Peripheral (PNS) Nervous Systems: An African Perspective. Front Immunol 2022; 13:833548. [PMID: 35356001 PMCID: PMC8959857 DOI: 10.3389/fimmu.2022.833548] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 02/10/2022] [Indexed: 11/13/2022] Open
Abstract
The direct impact and sequelae of infections in children and adults result in significant morbidity and mortality especially when they involve the central (CNS) or peripheral nervous system (PNS). The historical understanding of the pathophysiology has been mostly focused on the direct impact of the various pathogens through neural tissue invasion. However, with the better understanding of neuroimmunology, there is a rapidly growing realization of the contribution of the innate and adaptive host immune responses in the pathogenesis of many CNS and PNS diseases. The balance between the protective and pathologic sequelae of immunity is fragile and can easily be tipped towards harm for the host. The matter of immune privilege and surveillance of the CNS/PNS compartments and the role of the blood-brain barrier (BBB) and blood nerve barrier (BNB) makes this even more complex. Our understanding of the pathogenesis of many post-infectious manifestations of various microbial agents remains elusive, especially in the diverse African setting. Our exploration and better understanding of the neuroimmunology of some of the infectious diseases that we encounter in the continent will go a long way into helping us to improve their management and therefore lessen the burden. Africa is diverse and uniquely poised because of the mix of the classic, well described, autoimmune disease entities and the specifically "tropical" conditions. This review explores the current understanding of some of the para- and post-infectious autoimmune manifestations of CNS and PNS diseases in the African context. We highlight the clinical presentations, diagnosis and treatment of these neurological disorders and underscore the knowledge gaps and perspectives for future research using disease models of conditions that we see in the continent, some of which are not uniquely African and, where relevant, include discussion of the proposed mechanisms underlying pathogen-induced autoimmunity. This review covers the following conditions as models and highlight those in which a relationship with COVID-19 infection has been reported: a) Acute Necrotizing Encephalopathy; b) Measles-associated encephalopathies; c) Human Immunodeficiency Virus (HIV) neuroimmune disorders, and particularly the difficulties associated with classical post-infectious autoimmune disorders such as the Guillain-Barré syndrome in the context of HIV and other infections. Finally, we describe NMDA-R encephalitis, which can be post-HSV encephalitis, summarise other antibody-mediated CNS diseases and describe myasthenia gravis as the classic antibody-mediated disease but with special features in Africa.
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Affiliation(s)
- Alvin Pumelele Ndondo
- Department of Paediatric Neurology, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa
| | - Brian Eley
- Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa.,Paediatric Infectious Diseases Unit, Red Cross War Memorial Children's Hospital, Cape Town, South Africa
| | - Jo Madeleine Wilmshurst
- Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa.,Department of Paediatric Neurology, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Angelina Kakooza-Mwesige
- Department of Pediatrics and Child Health, School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Maria Pia Giannoccaro
- Laboratory of Neuromuscular Pathology and Neuroimmunology, Istituto di Ricovero e Cura a CarattereScientifico (IRCCS) Instiuto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica Bologna, Bologna, Italy.,Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Hugh J Willison
- Institute of Infection, Immunity and Inflammation (3I), University of Glasgow, Glasgow, United Kingdom
| | - Pedro M Rodríguez Cruz
- Centro Nacional de Analisis Genomico - Centre for Genomic Regulation (CNAG-CRG ), Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.,Department of Neuromuscular Disease, University College London (UCL) Queen Square Institute of Neurology, London, United Kingdom.,Faculté de Médecine, de Pharmacie et d'Odontologie, Université Cheikh Anta Diop, Dakar, Senegal
| | - Jeannine M Heckmann
- Neurology Division, Department of Medicine, Groote Schuur Hospital, Cape Town, South Africa.,The University of Cape Town (UCT) Neurosciences Institute, University of Cape Town, Cape Town, South Africa
| | - Kathleen Bateman
- Neurology Division, Department of Medicine, Groote Schuur Hospital, Cape Town, South Africa
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
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10
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Djuardi Y, Jannah IF, Supali T. IgG4 antibodies against Bm14 as an evaluation tool of mass drug administration in a co-endemic area of Brugia timori and Wuchereria bancrofti. Acta Trop 2022; 227:106278. [PMID: 34919952 DOI: 10.1016/j.actatropica.2021.106278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 11/09/2021] [Accepted: 12/11/2021] [Indexed: 11/01/2022]
Abstract
To evaluate the success of mass drug administration for lymphatic filariasis, WHO has recommended two rapid tests, Brugia Rapid (BR) to detect the presence of IgG4 antibodies against Brugia sp and Filariasis Test Strip (FTS) to detect antigens of Wuchereria bancrofti. As a country co-endemic for Brugia sp. and W. bancrofti, Indonesia needs a single diagnostic tool that can detect the exposure to both species. This study aimed to evaluate the efficacy of mass drug administration by measuring Bm14-specific IgG4 levels in blood samples of the population living in a co-endemic area of B. timori and W. bancrofti in Southwest Sumba Regency. A total of 132 plasma samples obtained before and one year after DEC-albendazole administration, which have been previously tested with BR and FTS, were examined for IgG4 against Bm14 using enzyme-linked immunosorbent assay. The results showed that before treatment all 32 individuals (100%) with BR+/ FTS+ were also positive for Bm14-specific IgG4, while in BR+ or FTS+ group there were >90% samples detected positive. At one year after treatment, positive results for Bm14-specific IgG4 were still detected in 96.9% samples with BR+/ FTS+, 78.8% samples with BR+/ FTS- and 82.9% samples with BR-/ FTS+. On the other hand, the BR-/ FTS- group also had high rate of Bm14-specific IgG4 positivity either before treatment (62,5%) and at one year after treatment (43.8%). The lowest decrease of Bm14-specific IgG4 positivity at one year after treatment was shown in the double positive group (3.1%), while the highest was in the double negative group (18.7%). The measurement of IgG4 against Bm14 has the potential as a sensitive diagnostic tool to evaluate the success of MDA in the areas co-endemic for B. timori and W. bancrofti.
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11
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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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12
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Gumisiriza N, Kugler M, Brusselaers N, Mubiru F, Anguzu R, Ningwa A, Ogwang R, Akun P, Mwaka AD, Abbo C, Sekibira R, Hotterbeekx A, Colebunders R, Marsh K, Idro R. Risk Factors for Nodding Syndrome and Other Forms of Epilepsy in Northern Uganda: A Case-Control Study. Pathogens 2021; 10:pathogens10111451. [PMID: 34832607 PMCID: PMC8621683 DOI: 10.3390/pathogens10111451] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/04/2021] [Accepted: 11/05/2021] [Indexed: 11/26/2022] Open
Abstract
Epidemiological studies suggest a link between onchocerciasis and various forms of epilepsy, including nodding syndrome (NS). The aetiopathology of onchocerciasis associated epilepsy remains unknown. This case-control study investigated potential risk factors that may lead to NS and other forms of non-nodding epilepsy (OFE) in northern Uganda. We consecutively recruited 154 persons with NS (aged between 8 and 20 years), and age-frequency matched them with 154 with OFE and 154 healthy community controls. Participants’ socio-demography, medical, family, and migration histories were recorded. We tested participants for O. volvulus serum antibodies. The 154 controls were used for both OFE and NS separately to determine associations. We recruited 462 people with a median age of 15 years (IQR 14, 17); 260 (56.4%) were males. Independent risk factors associated with the development of NS were the presence of O. volvulus antibodies [aOR 8.79, 95% CI (4.15–18.65), p-value < 0.001] and preterm birth [aOR 2.54, 95% CI (1.02–6.33), p-value = 0.046]. Risk factors for developing OFE were the presence of O. volvulus antibodies [aOR 8.83, 95% CI (4.48–17.86), p-value < 0.001] and being born in the period before migration to IDP camps [aOR 4.28, 95% CI (1.20–15.15), p-value = 0.024]. In conclusion, O. volvulus seropositivity was a risk factor to develop NS and OFE; premature birth was a potential co-factor. Living in IDP camps was not a risk factor for developing NS or OFE.
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Affiliation(s)
- Nolbert Gumisiriza
- Department of Mental Health, Kabale University School of Medicine, Kabale P.O. Box 317, Uganda;
| | - Marina Kugler
- Global Health Institute, University of Antwerp, 2600 Antwerp, Belgium; (M.K.); (N.B.); (A.H.); (R.C.)
| | - Nele Brusselaers
- Global Health Institute, University of Antwerp, 2600 Antwerp, Belgium; (M.K.); (N.B.); (A.H.); (R.C.)
- Centre for Translational Microbiome Research, Karolinska Institute, 17177 Stockholm, Sweden
| | - Frank Mubiru
- Department of Statistical methods, School of Statistics and Planning, College of Business and Management Sciences, Makerere University, Kampala P.O. Box 7062, Uganda;
| | - Ronald Anguzu
- College of Health Sciences, Makerere University, Kampala P.O. Box 7072, Uganda; (R.A.); (A.N.); (R.O.); (P.A.); (A.D.M.); (C.A.); (R.S.)
- Division of Epidemiology, Institute for Health and Equity, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Albert Ningwa
- College of Health Sciences, Makerere University, Kampala P.O. Box 7072, Uganda; (R.A.); (A.N.); (R.O.); (P.A.); (A.D.M.); (C.A.); (R.S.)
- Centre of Tropical Neuroscience, Kitgum Site, Kampala P.O. Box 27520, Uganda
| | - Rodney Ogwang
- College of Health Sciences, Makerere University, Kampala P.O. Box 7072, Uganda; (R.A.); (A.N.); (R.O.); (P.A.); (A.D.M.); (C.A.); (R.S.)
- Centre of Tropical Neuroscience, Kitgum Site, Kampala P.O. Box 27520, Uganda
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Coast, Kilifi P.O. Box 230-80108, Kenya
| | - Pamela Akun
- College of Health Sciences, Makerere University, Kampala P.O. Box 7072, Uganda; (R.A.); (A.N.); (R.O.); (P.A.); (A.D.M.); (C.A.); (R.S.)
- Centre of Tropical Neuroscience, Kitgum Site, Kampala P.O. Box 27520, Uganda
| | - Amos Deogratius Mwaka
- College of Health Sciences, Makerere University, Kampala P.O. Box 7072, Uganda; (R.A.); (A.N.); (R.O.); (P.A.); (A.D.M.); (C.A.); (R.S.)
| | - Catherine Abbo
- College of Health Sciences, Makerere University, Kampala P.O. Box 7072, Uganda; (R.A.); (A.N.); (R.O.); (P.A.); (A.D.M.); (C.A.); (R.S.)
| | - Rogers Sekibira
- College of Health Sciences, Makerere University, Kampala P.O. Box 7072, Uganda; (R.A.); (A.N.); (R.O.); (P.A.); (A.D.M.); (C.A.); (R.S.)
| | - An Hotterbeekx
- Global Health Institute, University of Antwerp, 2600 Antwerp, Belgium; (M.K.); (N.B.); (A.H.); (R.C.)
| | - Robert Colebunders
- Global Health Institute, University of Antwerp, 2600 Antwerp, Belgium; (M.K.); (N.B.); (A.H.); (R.C.)
| | - Kevin Marsh
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford OX3 7LG, UK;
| | - Richard Idro
- College of Health Sciences, Makerere University, Kampala P.O. Box 7072, Uganda; (R.A.); (A.N.); (R.O.); (P.A.); (A.D.M.); (C.A.); (R.S.)
- Centre of Tropical Neuroscience, Kitgum Site, Kampala P.O. Box 27520, Uganda
- Centre for Tropical Medicine and Global Health, University of Oxford, Oxford OX3 7LG, UK;
- Correspondence: author: ; Tel.: +256-774274173
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13
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Abraham D, Graham-Brown J, Carter D, Gray SA, Hess JA, Makepeace BL, Lustigman S. Development of a recombinant vaccine against human onchocerciasis. Expert Rev Vaccines 2021; 20:1459-1470. [PMID: 34488533 DOI: 10.1080/14760584.2021.1977125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 09/02/2021] [Indexed: 01/02/2023]
Abstract
INTRODUCTION Human onchocerciasis caused by the filarial nematode parasite Onchocerca volvulus remains a major cause of debilitating disease infecting millions primarily in Sub-Saharan Africa. The development of a prophylactic vaccine, along with mass drug administration, would facilitate meeting the goal of onchocerciasis elimination by 2030. AREAS COVERED Models used to study immunity to Onchocerca include natural infection of cattle with Onchocerca ochengi and O. volvulus infective third-stage larvae implanted within diffusion chambers in mice. A vaccine, comprised of two adjuvanted recombinant antigens, induced protective immunity in genetically diverse mice suggesting that it will function similarly in diverse human populations. These antigens were recognized by immune humans and also induced protective immunity against Brugia malayi. We describe the development of a fusion protein composed of the two vaccine antigens with the plan to test the vaccine in cows and non-human primates as a prelude to the initiation of phase 1 clinical trials. EXPERT OPINION The adjuvanted O. volvulus vaccine composed of two antigens Ov-103 and Ov-RAL-2 was shown to be consistently effective at inducing protective immunity using multiple immune mechanisms. The vaccine is ready for further evaluation in other animal models before moving to clinical trials in humans.
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Affiliation(s)
- David Abraham
- Department of Microbiology and Immunology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - John Graham-Brown
- Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Liverpool, UK
| | | | | | - Jessica A Hess
- Department of Microbiology and Immunology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Benjamin L Makepeace
- Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Sara Lustigman
- Laboratory of Molecular Parasitology, Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, USA
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14
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Shintouo CM, Shey RA, Mets T, Vanhamme L, Souopgui J, Ghogomu SM, Njemini R. Onchocerciasis Fingerprints in the Geriatric Population: Does Host Immunity Play a Role? Trop Med Infect Dis 2021; 6:tropicalmed6030153. [PMID: 34449738 PMCID: PMC8396225 DOI: 10.3390/tropicalmed6030153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/16/2021] [Accepted: 08/18/2021] [Indexed: 11/16/2022] Open
Abstract
One of the most debilitating consequences of aging is the progressive decline in immune function, known as immunosenescence. This phenomenon is characterized by a shift in T-cell phenotypes, with a manifest decrease of naive T-cells-dealing with newly encountered antigens-and a concomitant accumulation of senescent and regulatory T-cells, leading to a greater risk of morbidity and mortality in older subjects. Additionally, with aging, several studies have unequivocally revealed an increase in the prevalence of onchocerciasis infection. Most lymphatic complications, skin and eye lesions due to onchocerciasis are more frequent among the elderly population. While the reasons for increased susceptibility to onchocerciasis with age are likely to be multi-factorial, age-associated immune dysfunction could play a key role in the onset and progression of the disease. On the other hand, there is a growing consensus that infection with onchocerciasis may evoke deleterious effects on the host's immunity and exacerbate immune dysfunction. Indeed, Onchocerca volvulus has been reported to counteract the immune responses of the host through molecular mimicry by impairing T-cell activation and interfering with the processing of antigens. Moreover, reports indicate impaired cellular and humoral immune responses even to non-parasite antigens in onchocerciasis patients. This diminished protective response may intensify the immunosenescence outcomes, with a consequent vulnerability of those affected to additional diseases. Taken together, this review is aimed at contributing to a better understanding of the immunological and potential pathological mechanisms of onchocerciasis in the older population.
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Affiliation(s)
- Cabirou Mounchili Shintouo
- Frailty in Ageing Research Group, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium; (C.M.S.); (T.M.)
- Department of Gerontology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea P.O. Box 63, Cameroon; (R.A.S.); (S.M.G.)
| | - Robert Adamu Shey
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea P.O. Box 63, Cameroon; (R.A.S.); (S.M.G.)
| | - Tony Mets
- Frailty in Ageing Research Group, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium; (C.M.S.); (T.M.)
- Department of Gerontology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
| | - Luc Vanhamme
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies Campus, 126040 Gosselies, Belgium; (L.V.); (J.S.)
| | - Jacob Souopgui
- Department of Molecular Biology, Institute of Biology and Molecular Medicine, IBMM, Université Libre de Bruxelles, Gosselies Campus, 126040 Gosselies, Belgium; (L.V.); (J.S.)
| | - Stephen Mbigha Ghogomu
- Department of Biochemistry and Molecular Biology, Faculty of Science, University of Buea, Buea P.O. Box 63, Cameroon; (R.A.S.); (S.M.G.)
| | - Rose Njemini
- Frailty in Ageing Research Group, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium; (C.M.S.); (T.M.)
- Department of Gerontology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
- Correspondence: ; Tel.: +32-24774241
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15
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Souza AA, Ducker C, Argaw D, King JD, Solomon AW, Biamonte MA, Coler RN, Cruz I, Lejon V, Levecke B, Marchini FK, Marks M, Millet P, Njenga SM, Noordin R, Paulussen R, Sreekumar E, Lammie PJ. Diagnostics and the neglected tropical diseases roadmap: setting the agenda for 2030. Trans R Soc Trop Med Hyg 2021; 115:129-135. [PMID: 33169166 PMCID: PMC7842105 DOI: 10.1093/trstmh/traa118] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/07/2020] [Accepted: 10/16/2020] [Indexed: 11/12/2022] Open
Abstract
Accurate and reliable diagnostic tools are an essential requirement for neglected tropical diseases (NTDs) programmes. However, the NTD community has historically underinvested in the development and improvement of diagnostic tools, potentially undermining the successes achieved over the last 2 decades. Recognizing this, the WHO, in its newly released draft roadmap for NTD 2021-2030, has identified diagnostics as one of four priority areas requiring concerted action to reach the 2030 targets. As a result, WHO established a Diagnostics Technical Advisory Group (DTAG) to serve as the collaborative mechanism to drive progress in this area. Here, the purpose and role of the DTAG are described in the context of the challenges facing NTD programmes.
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Affiliation(s)
- Ashley A Souza
- Neglected Tropical Diseases Support Center, Task Force for Global Health, Atlanta, GA 30030, USA
| | - Camilla Ducker
- Consultant, World Health Organization, Geneva, Switzerland
| | - Daniel Argaw
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Jonathan D King
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Anthony W Solomon
- Department of Control of Neglected Tropical Diseases, World Health Organization, Geneva, Switzerland
| | - Marco A Biamonte
- Drugs and Diagnostics for Tropical Diseases, San Diego, CA 92111, USA
| | - Rhea N Coler
- Center for Global Infectious Disease Research, Seattle Children's Research Institute, Seattle, WA, USA
| | - Israel Cruz
- National School of Public Health, Instituto de Salud Carlos III, Madrid, Spain
| | - Veerle Lejon
- Institut de Recherche pour le Développement, University of Montpellier, Montpellier, France
| | - Bruno Levecke
- Department of Virology, Parasitology and Immunology, Ghent University, Faculty of Veterinary Medicine, Salisburylaan 133, B-9820 Merelbeke, Belgium
| | | | - Michael Marks
- Clinical Research Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, WC1E 7HT, UK
| | - Pascal Millet
- Laboratoire de Parasitologie, Université de Bordeaux, Bordeaux, France
| | | | - Rahmah Noordin
- Institute for Research in Molecular Medicine, Universiti Sains Malaysia, Pengang, Malaysia
| | | | - Esvawaran Sreekumar
- Molecular Virology Laboratory, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
| | - Patrick J Lammie
- Neglected Tropical Diseases Support Center, Task Force for Global Health, Atlanta, GA 30030, USA
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16
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Ogwang R, Ningwa A, Akun P, Bangirana P, Anguzu R, Mazumder R, Salamon N, Henning OJ, Newton CR, Abbo C, Mwaka AD, Marsh K, Idro R. Epilepsy in Onchocerca volvulus Sero-Positive Patients From Northern Uganda-Clinical, EEG and Brain Imaging Features. Front Neurol 2021; 12:687281. [PMID: 34149607 PMCID: PMC8209377 DOI: 10.3389/fneur.2021.687281] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 05/12/2021] [Indexed: 01/08/2023] Open
Abstract
Globally, epilepsy is the most common chronic neurological disorder. The incidence in sub-Saharan Africa is 2-3 times higher than that in high income countries. Infection by Onchocerca volvulus may be an underlying risk factor for the high burden and based upon epidemiological associations, has been proposed to cause a group of disorders—Onchocerca associated epilepsies (OAE) like nodding syndrome (NS). To improve our understanding of the disease spectrum, we described the clinical, electroencephalographic (EEG) and magnetic resonance imaging (MRI) features of children with epilepsy and sero-positive for Onchocerca volvulus (possible OAEs other than nodding syndrome). Twenty-nine children and adolescents with non-nodding syndrome OAE in northern Uganda were enrolled. A diagnosis of OAE was made in patients with epilepsy and seizure onset after age 3 years, no reported exposure to perinatal severe febrile illness or traumatic brain injury, no syndromic epilepsy diagnosis and a positive Ov-16 ELISA test. Detailed clinical evaluation including psychiatric, diagnostic EEG, a diagnostic brain MRI (in 10 patients) and laboratory testing were performed. Twenty participants (69%) were male. The mean age was 15.9 (standard deviation [SD] 1.9) years while the mean age at seizure onset was 9.8 (SD 2.9) years. All reported normal early childhood development. The most common clinical presentation was a tonic-clonic seizure. The median number of seizures was 2 (IQR 1–4) in the previous month. No specific musculoskeletal changes, or cranial nerve palsies were reported, neither were any vision, hearing and speech difficulties observed. The interictal EEG was abnormal in the majority with slow wave background activity in 52% (15/29) while 41% (12/29) had focal epileptiform activity. The brain MRI showed mild to moderate cerebellar atrophy and varying degrees of atrophy of the frontal, parietal and occipital lobes. The clinical spectrum of epilepsies associated with Onchocerca may be broader than previously described. In addition, focal onset tonic-clonic seizures, cortical and cerebellar atrophy may be important brain imaging and clinical features.
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Affiliation(s)
- Rodney Ogwang
- College of Health Sciences, Makerere University, Kampala, Uganda.,KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Coast, Kilifi, Kenya.,Centre of Tropical Neuroscience, Kitgum, Uganda
| | - Albert Ningwa
- College of Health Sciences, Makerere University, Kampala, Uganda.,Centre of Tropical Neuroscience, Kitgum, Uganda
| | - Pamela Akun
- College of Health Sciences, Makerere University, Kampala, Uganda.,Centre of Tropical Neuroscience, Kitgum, Uganda
| | - Paul Bangirana
- College of Health Sciences, Makerere University, Kampala, Uganda
| | - Ronald Anguzu
- College of Health Sciences, Makerere University, Kampala, Uganda.,Centre of Tropical Neuroscience, Kitgum, Uganda.,Division of Epidemiology, Medical College of Wisconsin, Institute for Health and Equity, Milwaukee, WI, United States
| | - Rajarshi Mazumder
- Department of Neurology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Noriko Salamon
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Oliver Johannes Henning
- Division of Clinical Neuroscience, The National Centre for Epilepsy, Oslo University Hospital, Oslo, Norway
| | - Charles R Newton
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Coast, Kilifi, Kenya.,Department of Psychiatry, University of Oxford, Oxford, United Kingdom
| | - Catherine Abbo
- College of Health Sciences, Makerere University, Kampala, Uganda
| | | | - Kevin Marsh
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
| | - Richard Idro
- College of Health Sciences, Makerere University, Kampala, Uganda.,Centre of Tropical Neuroscience, Kitgum, Uganda.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
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17
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Brattig NW, Cheke RA, Garms R. Onchocerciasis (river blindness) - more than a century of research and control. Acta Trop 2021; 218:105677. [PMID: 32857984 DOI: 10.1016/j.actatropica.2020.105677] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 08/06/2020] [Accepted: 08/21/2020] [Indexed: 12/14/2022]
Abstract
This review summarises more than a century of research on onchocerciasis, also known as river blindness, and its control. River blindness is an infection caused by the tissue filaria Onchocerca volvulus affecting the skin, subcutaneous tissue and eyes and leading to blindness in a minority of infected persons. The parasite is transmitted by its intermediate hosts Simulium spp. which breed in rivers. Featured are history and milestones in onchocerciasis research and control, state-of-the-art data on the parasite, its endobacteria Wolbachia, on the vectors, previous and current prevalence of the infection, its diagnostics, the interaction between the parasite and its host, immune responses and the pathology of onchocerciasis. Detailed information is documented on the time course of control programmes in the afflicted countries in Africa and the Americas, a long road from previous programmes to current successes in control of the transmission of this infectious disease. By development, adjustment and optimization of the control measures, transmission by the vector has been interrupted in foci of countries in the Americas, in Uganda, in Sudan and elsewhere, followed by onchocerciasis eliminations. The current state and future perspectives for control, elimination and eradication within the next 20-30 years are described and discussed. This review contributes to a deeper comprehension of this disease by a tissue-dwelling filaria and it will be helpful in efforts to control and eliminate other filarial infections.
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18
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Ogwang R, Muhanguzi D, Mwikali K, Anguzu R, Kubofcik J, Nutman TB, Taylor M, Newton CR, Vincent A, Conroy AL, Marsh K, Idro R. Systemic and cerebrospinal fluid immune and complement activation in Ugandan children and adolescents with long-standing nodding syndrome: A case-control study. Epilepsia Open 2021; 6:297-309. [PMID: 34033255 PMCID: PMC8166803 DOI: 10.1002/epi4.12463] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/03/2020] [Accepted: 12/17/2020] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVE Nodding syndrome is a poorly understood epileptic encephalopathy characterized by a unique seizure type-head nodding-and associated with Onchocerca volvulus infection. We hypothesized that altered immune activation in the cerebrospinal fluid (CSF) and plasma of children with nodding syndrome may yield insights into the pathophysiology and progression of this seizure disorder. METHOD We conducted a case-control study of 154 children (8 years or older) with long-standing nodding syndrome and 154 healthy age-matched community controls in 3 districts of northern Uganda affected by nodding syndrome. Control CSF samples were obtained from Ugandan children in remission from hematological malignancy during routine follow-up. Markers of immune activation and inflammation (cytokines and chemokines) and complement activation (C5a) were measured in plasma and CSF using ELISA or Multiplex Luminex assays. O volvulus infection was assessed by serology for anti-OV-16 IgG levels. RESULTS The mean (SD) age of the population was 15.1 (SD: 1.9) years, and the mean duration of nodding syndrome from diagnosis to enrollment was 8.3 (SD: 2.7) years. The majority with nodding syndrome had been exposed to O volvulus (147/154 (95.4%)) compared with community children (86/154 (55.8%)), with an OR of 17.04 (95% CI: 7.33, 45.58), P < .001. C5a was elevated in CSF of children with nodding syndrome compared to controls (P < .0001). The levels of other CSF markers tested were comparable between cases and controls after adjusting for multiple comparisons. Children with nodding syndrome had lower plasma levels of IL-10, APRIL, CCL5 (RANTES), CCL2, CXCL13, and MMP-9 compared with community controls (P < .05 for all; multiple comparisons). Plasma CRP was elevated in children with nodding syndrome compared to community children and correlated with disease severity. SIGNIFICANCE Nodding syndrome is associated with exposure to O. volvulus. Compared to controls, children with long-standing symptoms of nodding syndrome show evidence of complement activation in CSF and altered immune activation in plasma.
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Affiliation(s)
- Rodney Ogwang
- Makerere University College of Health Sciences, Kampala, Uganda.,Centre of Tropical Neuroscience (CTN), Kitgum Site, Uganda.,KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Coast, Kilifi, Kenya
| | - Dennis Muhanguzi
- College of Veterinary Medicine Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | - Kioko Mwikali
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Coast, Kilifi, Kenya
| | - Ronald Anguzu
- Centre of Tropical Neuroscience (CTN), Kitgum Site, Uganda.,Division of Epidemiology, Institute of Health and Equity, Medical College of Wisconsin, Wisconsin, WI, USA
| | - Joe Kubofcik
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Thomas B Nutman
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA
| | - Mark Taylor
- Liverpool School of Tropical Medicine, Liverpool, UK
| | - Charles R Newton
- KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine Coast, Kilifi, Kenya.,Department of Psychiatry, University of Oxford, Oxford, UK
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Andrea L Conroy
- Indiana University School of Medicine, Ryan White Center for Pediatric Infectious Disease & Global Health, Indianapolis, IN, USA
| | - Kevin Marsh
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Richard Idro
- Makerere University College of Health Sciences, Kampala, Uganda.,Centre of Tropical Neuroscience (CTN), Kitgum Site, Uganda.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
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19
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Gazzinelli-Guimaraes PH, Bennuru S, de Queiroz Prado R, Ricciardi A, Sciurba J, Kupritz J, Moser M, Kamenyeva O, Nutman TB. House dust mite sensitization drives cross-reactive immune responses to homologous helminth proteins. PLoS Pathog 2021; 17:e1009337. [PMID: 33651853 PMCID: PMC7924806 DOI: 10.1371/journal.ppat.1009337] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 01/25/2021] [Indexed: 02/06/2023] Open
Abstract
The establishment of type 2 responses driven by allergic sensitization prior to exposure to helminth parasites has demonstrated how tissue-specific responses can protect against migrating larval stages, but, as a consequence, allow for immune-mediated, parasite/allergy-associated morbidity. In this way, whether helminth cross-reacting allergen-specific antibodies are produced and play a role during the helminth infection, or exacerbate the allergic outcome awaits elucidation. Thus, the main objective of the study was to investigate whether house dust mite (HDM) sensitization triggers allergen-specific antibodies that interact with Ascaris antigens and mediate antibody-dependent deleterious effects on these parasites as well as, to assess the capacity of cross-reactive helminth proteins to trigger allergic inflammation in house dust mite presensitized mice. Here, we show that the sensitization with HDM-extract drives marked IgE and IgG1 antibody responses that cross-react with Ascaris larval antigens. Proteomic analysis of Ascaris larval antigens recognized by these HDM-specific antibodies identified Ascaris tropomyosin and enolase as the 2 major HDM homologues based on high sequence and structural similarity. Moreover, the helminth tropomyosin could drive Type-2 associated pulmonary inflammation similar to HDM following HDM tropomyosin sensitization. The HDM-triggered IgE cross-reactive antibodies were found to be functional as they mediated immediate hypersensitivity responses in skin testing. Finally, we demonstrated that HDM sensitization in either B cells or FcγRIII alpha-chain deficient mice indicated that the allergen driven cell-mediated larval killing is not antibody-dependent. Taken together, our data suggest that aeroallergen sensitization drives helminth reactive antibodies through molecular and structural similarity between HDM and Ascaris antigens suggesting that cross-reactive immune responses help drive allergic inflammation. Epidemiological studies related to the interaction between allergies and helminth infection led to the observations that helped shape the so-called hygiene hypothesis, which generally states that chronic exposure to helminths diminishes the risk of the development of allergic disease. However, there are conflicting studies that have called this particular hypothesis into question, such as, the studies that suggest that infection with the helminth Ascaris lumbricoides is a risk factor for wheezing and atopy or can aggravate the clinical symptoms of asthma. A hypothetical explanation for such phenomenon is the fact that there is a high degree of molecular and structural similarities among helminth antigens with many common allergens, including the house dust mite (HDM). This high degree of homology of certain epitopes shared between helminths and allergens generate cross-react antibodies which may play a role in the pathogenesis or regulation of both conditions. Thus, this study aimed to understand the structural basis for cross-reactive antibodies induced by HDM sensitization. Here, we demonstrate that HDM sensitization drives helminth cross-reactive antibodies through molecular and structural homology between tropomyosins and enolases. This study highlights the pro-allergenic properties of HDM and helminth proteins that share homologous epitopes.
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Affiliation(s)
| | - Sasisekhar Bennuru
- Laboratory of Parasitic Diseases, NIAID, National Institutes of Health; Bethesda, Maryland, United States of America
| | - Rafael de Queiroz Prado
- Laboratory of Parasitic Diseases, NIAID, National Institutes of Health; Bethesda, Maryland, United States of America
| | - Alessandra Ricciardi
- Laboratory of Parasitic Diseases, NIAID, National Institutes of Health; Bethesda, Maryland, United States of America
| | - Joshua Sciurba
- Laboratory of Parasitic Diseases, NIAID, National Institutes of Health; Bethesda, Maryland, United States of America
| | - Jonah Kupritz
- Laboratory of Parasitic Diseases, NIAID, National Institutes of Health; Bethesda, Maryland, United States of America
| | - Matthew Moser
- Laboratory of Parasitic Diseases, NIAID, National Institutes of Health; Bethesda, Maryland, United States of America
| | - Olena Kamenyeva
- Biological Imaging Section of Research Technologies Branch, National Institutes of Health; Bethesda, Maryland, United States of America
| | - Thomas B. Nutman
- Laboratory of Parasitic Diseases, NIAID, National Institutes of Health; Bethesda, Maryland, United States of America
- * E-mail: (PHGG); (TBN)
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Jawahar S, Tricoche N, Bulman CA, Sakanari J, Lustigman S. Drugs that target early stages of Onchocerca volvulus: A revisited means to facilitate the elimination goals for onchocerciasis. PLoS Negl Trop Dis 2021; 15:e0009064. [PMID: 33600426 PMCID: PMC7891776 DOI: 10.1371/journal.pntd.0009064] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Several issues have been identified with the current programs for the elimination of onchocerciasis that target only transmission by using mass drug administration (MDA) of the drug ivermectin. Alternative and/or complementary treatment regimens as part of a more comprehensive strategy to eliminate onchocerciasis are needed. We posit that the addition of “prophylactic” drugs or therapeutic drugs that can be utilized in a prophylactic strategy to the toolbox of present microfilaricidal drugs and/or future macrofilaricidal treatment regimens will not only improve the chances of meeting the elimination goals but may hasten the time to elimination and also will support achieving a sustained elimination of onchocerciasis. These “prophylactic” drugs will target the infective third- (L3) and fourth-stage (L4) larvae of Onchocerca volvulus and consequently prevent the establishment of new infections not only in uninfected individuals but also in already infected individuals and thus reduce the overall adult worm burden and transmission. Importantly, an effective prophylactic treatment regimen can utilize drugs that are already part of the onchocerciasis elimination program (ivermectin), those being considered for MDA (moxidectin), and/or the potential macrofilaricidal drugs (oxfendazole and emodepside) currently under clinical development. Prophylaxis of onchocerciasis is not a new concept. We present new data showing that these drugs can inhibit L3 molting and/or inhibit motility of L4 at IC50 and IC90 that are covered by the concentration of these drugs in plasma based on the corresponding pharmacological profiles obtained in human clinical trials when these drugs were tested using various doses for the therapeutic treatments of various helminth infections.
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Affiliation(s)
- Shabnam Jawahar
- Molecular Parasitology, Lindsey F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
| | - Nancy Tricoche
- Molecular Parasitology, Lindsey F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
| | - Christina A Bulman
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | - Judy Sakanari
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | - Sara Lustigman
- Molecular Parasitology, Lindsey F. Kimball Research Institute, New York Blood Center, New York, New York, United States of America
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21
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Entomological Assessment of Onchocerca Species Transmission by Black Flies in Selected Communities in the West Region of Cameroon. Pathogens 2020; 9:pathogens9090722. [PMID: 32887231 PMCID: PMC7559537 DOI: 10.3390/pathogens9090722] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 08/29/2020] [Accepted: 08/31/2020] [Indexed: 12/20/2022] Open
Abstract
The enormity of the public health burden of onchocerciasis motivated the creation of various large-scale control programs that have depended principally on mass treatment of endemic communities with ivermectin for the elimination of the disease. Parasitological evaluation of Onchocerca species in the West Region of Cameroon indicates significant progress in the interruption of parasite transmission in some communities under ivermectin treatment. However, to verify the complete elimination of onchocerciasis, entomological assessment through O-150 PCR poolscreen of black flies is mandatory. Thus, in the present study, we assessed transmission of Onchocerca species using an O-150 PCR technique to screen pools of black flies—in seven onchocerciasis endemic communities (Makouopsap, Bankambe, Lemgo, Tsesse, Ndionzou, Kouffen, and Bayon) in Cameroon. Two thousand black flies were assessed—in each community—for the presence of Onchocerca species DNA. Our results show that the frequency of infective flies was 0.6% in Makouopsap and 0.0% in the other communities. On the other hand, the frequency of infected flies was 0.8% in Makouopsap, 0.2% in Bankambe, 0.1% in Bayon, and 0.0% in Lemgo, Tsesse, Ndionzou, and Kouffen. These results provide entomologic evidence for continuous transmission of Onchocerca species in Makouopsap, risk of active transmission in Bankambe, and Bayon, and a suppressed transmission in the four other studied communities.
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In Silico Design and Validation of OvMANE1, a Chimeric Antigen for Human Onchocerciasis Diagnosis. Pathogens 2020; 9:pathogens9060495. [PMID: 32580355 PMCID: PMC7350323 DOI: 10.3390/pathogens9060495] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/12/2020] [Accepted: 06/18/2020] [Indexed: 02/06/2023] Open
Abstract
The public health goal of onchocerciasis in Africa has advanced from control to elimination. In this light, accurate diagnosis is necessary to determine treatment endpoints and confirm elimination, as well as to conduct surveillance for the identification of any possible recrudescence of the disease. Currently, the monitoring of onchocerciasis elimination relies on the Ov-16 test. However, this test is unable to discriminate between past and active infections. Furthermore, about 15-25% of infected persons are reported to be negative for the Ov-16 test, giving a misleading sense of security to false-negative individuals who might continue to serve as reservoirs for infections. Therefore, we opted to design and validate a more sensitive and specific chimeric antigen (OvMANE1) for onchocerciasis diagnosis, using previously reported immunodominant peptides of O. volvulus, the parasite responsible for the disease. In silico analysis of OvMANE1 predicted it to be more antigenic than its individual peptides. We observed that OvMANE1 reacts specifically and differentially with sera from O. volvulus infected and non-infected individuals, as well as with sera from communities of different levels of endemicity. Moreover, we found that total IgG, unlike IgG4 subclass, positively responded to OvMANE1, strongly suggesting its complementarity to the Ov-16 diagnostic tool, which detects Ov-16 IgG4 antibodies. Overall, OvMANE1 exhibited the potential to be utilized in the development of specific diagnostic tools-based on both antibody capture and antigen capture reactions-which are indispensable to monitor the progress of onchocerciasis elimination programs.
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Hotterbeekx A, Perneel J, Mandro M, Abhafule G, Siewe Fodjo JN, Dusabimana A, Abrams S, Kumar-Singh S, Colebunders R. Comparison of Diagnostic Tests for Onchocerca volvulus in the Democratic Republic of Congo. Pathogens 2020; 9:pathogens9060435. [PMID: 32498284 PMCID: PMC7350314 DOI: 10.3390/pathogens9060435] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/20/2020] [Accepted: 06/01/2020] [Indexed: 12/16/2022] Open
Abstract
Onchocerciasis is diagnosed by detecting microfilariae in skin snips or by detecting OV16 IgG4 antibodies in blood by either enzyme linked immunosorbent assay (ELISA) or a rapid diagnostic test (RDT). Here, we compare the sensitivity and specificity of these three tests in persons with epilepsy living in an onchocerciasis endemic region in the Democratic Republic of Congo. Skin snips and blood samples were collected from 285 individuals for onchocerciasis diagnosis. Three tests were performed: the OV16 RDT (SD Bioline) and the OV16 ELISA both on serum samples, and microscopic detection of microfilariae in skin snips. The sensitivity and specificity of each test was calculated with the combined other tests as a reference. Microfilariae were present in 105 (36.8%) individuals, with a median of 18.5 (6.5–72.0) microfilariae/skin snip. The OV16 RDT and OV16 ELISA were positive in, respectively, 112 (39.3%) and 143 (50.2%) individuals. The OV16 ELISA had the highest sensitivity among the three tests (83%), followed by the OV16 RDT (74.8%) and the skin snip (71.4%). The OV16 RDT had a higher specificity (98.6%) compared to the OV16 ELISA (84.8%). Our study confirms the need to develop more sensitive tests to ensure the accurate detection of ongoing transmission before stopping elimination efforts.
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Affiliation(s)
- An Hotterbeekx
- Global Health Institute, University of Antwerp, 2000 Antwerp, Belgium; (J.P.); (J.N.S.F.); (A.D.); (S.A.); (R.C.)
- Correspondence: ; Tel.: +32-3-265-27-52; Fax: +32-3-265-26-63
| | - Jolien Perneel
- Global Health Institute, University of Antwerp, 2000 Antwerp, Belgium; (J.P.); (J.N.S.F.); (A.D.); (S.A.); (R.C.)
| | - Michel Mandro
- Provincial Health Division Ituri, Ministry of Health, Bunia 185 DRC 57, Democratic Republic of Congo;
- Centre de Recherche en Maladies Tropicales, Rethy Box 143, Democratic Republic of Congo;
| | - Germain Abhafule
- Centre de Recherche en Maladies Tropicales, Rethy Box 143, Democratic Republic of Congo;
| | - Joseph Nelson Siewe Fodjo
- Global Health Institute, University of Antwerp, 2000 Antwerp, Belgium; (J.P.); (J.N.S.F.); (A.D.); (S.A.); (R.C.)
| | - Alfred Dusabimana
- Global Health Institute, University of Antwerp, 2000 Antwerp, Belgium; (J.P.); (J.N.S.F.); (A.D.); (S.A.); (R.C.)
| | - Steven Abrams
- Global Health Institute, University of Antwerp, 2000 Antwerp, Belgium; (J.P.); (J.N.S.F.); (A.D.); (S.A.); (R.C.)
| | - Samir Kumar-Singh
- Molecular Pathology Group, Laboratory of Cell Biology & Histology, Faculty of Medicine and Health Sciences, University of Antwerp, 2000 Antwerp, Belgium;
| | - Robert Colebunders
- Global Health Institute, University of Antwerp, 2000 Antwerp, Belgium; (J.P.); (J.N.S.F.); (A.D.); (S.A.); (R.C.)
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Colebunders R, Stolk WA, Siewe Fodjo JN, Mackenzie CD, Hopkins A. Elimination of onchocerciasis in Africa by 2025: an ambitious target requires ambitious interventions. Infect Dis Poverty 2019; 8:83. [PMID: 31578157 PMCID: PMC6775645 DOI: 10.1186/s40249-019-0593-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 09/04/2019] [Indexed: 11/10/2022] Open
Abstract
To achieve the elimination of onchocerciasis transmission in all African countries will entail enormous challenges, as has been highlighted by the active discussion around onchocerciasis intervention strategies and evaluation procedures in this journal.Serological thresholds for onchocerciasis elimination, adapted for the African setting, need to be established. The Onchocerciasis Technical Advisory Subgroup of the World Health Organization is currently developing improved guidelines to allow country elimination committees to make evidence-based decisions. Importantly, onchocerciasis-related morbidity should not be forgotten when debating elimination prospects. A morbidity management and disease prevention (MMDP) strategy similar to that for lymphatic filariasis will need to be developed. This will require collaboration between the onchocerciasis elimination program, the community and other partners including primary health and mental health programs.In order to reach the goal of onchocerciasis elimination in most African countries by 2025, we should prioritize community participation and advocate for tailored interventions which are scientifically proven to be effective, but currently considered to be too expensive.
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Affiliation(s)
| | - Wilma A Stolk
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | | | | | - Adrian Hopkins
- Neglected and Disabling Diseases of Poverty Consultant, Gravesend, Kent, UK
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