1
|
Reuter C, Hauf L, Imdahl F, Sen R, Vafadarnejad E, Fey P, Finger T, Jones NG, Walles H, Barquist L, Saliba AE, Groeber-Becker F, Engstler M. Vector-borne Trypanosoma brucei parasites develop in artificial human skin and persist as skin tissue forms. Nat Commun 2023; 14:7660. [PMID: 37996412 PMCID: PMC10667367 DOI: 10.1038/s41467-023-43437-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Accepted: 11/08/2023] [Indexed: 11/25/2023] Open
Abstract
Transmission of Trypanosoma brucei by tsetse flies involves the deposition of the cell cycle-arrested metacyclic life cycle stage into mammalian skin at the site of the fly's bite. We introduce an advanced human skin equivalent and use tsetse flies to naturally infect the skin with trypanosomes. We detail the chronological order of the parasites' development in the skin by single-cell RNA sequencing and find a rapid activation of metacyclic trypanosomes and differentiation to proliferative parasites. Here we show that after the establishment of a proliferative population, the parasites enter a reversible quiescent state characterized by slow replication and a strongly reduced metabolism. We term these quiescent trypanosomes skin tissue forms, a parasite population that may play an important role in maintaining the infection over long time periods and in asymptomatic infected individuals.
Collapse
Affiliation(s)
- Christian Reuter
- Department of Cell and Developmental Biology, Biocenter, Julius-Maximilians-Universitaet of Wuerzburg, Wuerzburg, Germany
- Department of Tissue Engineering and Regenerative Medicine (TERM), University Hospital Wuerzburg, Wuerzburg, Germany
| | - Laura Hauf
- Department of Cell and Developmental Biology, Biocenter, Julius-Maximilians-Universitaet of Wuerzburg, Wuerzburg, Germany
| | - Fabian Imdahl
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Center for Infection Research (HZI), Wuerzburg, Germany
- Core Unit Systems Medicine, Julius-Maximilians-Universitaet of Wuerzburg, Wuerzburg, Germany
| | - Rituparno Sen
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Center for Infection Research (HZI), Wuerzburg, Germany
| | - Ehsan Vafadarnejad
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Center for Infection Research (HZI), Wuerzburg, Germany
| | - Philipp Fey
- Translational Center Regenerative Therapies, Fraunhofer ISC, Wuerzburg, Germany
| | - Tamara Finger
- Translational Center Regenerative Therapies, Fraunhofer ISC, Wuerzburg, Germany
| | - Nicola G Jones
- Department of Cell and Developmental Biology, Biocenter, Julius-Maximilians-Universitaet of Wuerzburg, Wuerzburg, Germany
| | - Heike Walles
- Translational Center Regenerative Therapies, Fraunhofer ISC, Wuerzburg, Germany
- Core Facility Tissue Engineering, Otto-von-Guericke University, Magdeburg, Germany
| | - Lars Barquist
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Center for Infection Research (HZI), Wuerzburg, Germany
| | - Antoine-Emmanuel Saliba
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Center for Infection Research (HZI), Wuerzburg, Germany
- Institute of Molecular Infection Biology (IMIB), Faculty of Medicine, Julius-Maximilians-Universitaet of Wuerzburg, Wuerzburg, Germany
| | - Florian Groeber-Becker
- Department of Tissue Engineering and Regenerative Medicine (TERM), University Hospital Wuerzburg, Wuerzburg, Germany
- Translational Center Regenerative Therapies, Fraunhofer ISC, Wuerzburg, Germany
| | - Markus Engstler
- Department of Cell and Developmental Biology, Biocenter, Julius-Maximilians-Universitaet of Wuerzburg, Wuerzburg, Germany.
| |
Collapse
|
2
|
Anyogu DC, Shoyinka SVO, Ihedioha JI. Infection of West African dwarf rams with Trypanosoma brucei brucei and Trypanosoma congolense significantly alter serum electrolytes, redox balance, sperm parameters, and gonadal morphology. Vet Res Commun 2023; 47:17-27. [PMID: 35389159 DOI: 10.1007/s11259-022-09921-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 03/23/2022] [Indexed: 01/27/2023]
Abstract
Trypanotolerance of the West African dwarf (WAD) breeds may not rule out significant pathophysiological changes that may affect productivity. In this study, the effects of infection of WAD rams with Trypanosoma brucei brucei (Tbb) and Trypanosoma congolense (Tc) on their serum levels of electrolytes [calcium, phosphorus, sodium, potassium]; oxidative stress markers [superoxide dismutase (SOD), malondialdehyde (MDA)]; and sperm parameters [sperm count, motility, vitality, and morphology] were investigated. Fifteen WAD rams, assigned to 3 groups (A, B & C) of 5 rams each, were used for the study. Group A rams were infected with Tbb, while Group B rams were infected with Tc, both intraperitoneally, at the dose of 106 trypanosomes/animal. Group C rams served as the uninfected control. The infections were monitored for 70 days. Serum calcium levels were significantly (p < 0.05) lower in Tbb and Tc infected rams compared to the control throughout the study. Serum sodium was significantly (p < 0.05) higher in the Tb infected rams compared to the Tc infected and control rams on days 14 and 28 PI. Serum SOD activity decreased while MDA levels increased in both infected groups of rams. Tbb infected rams were azoospermic, while Tc infected rams had lower sperm motility, vitality and concentration, and higher number of abnormal sperm cells compared to the control. Necrotic and inflammatory lesions occurred in the testis and epididymis of both infected rams. These results suggest that despite trypanotolerance, trypanosome infections in the WAD rams significantly impact on health and reproduction.
Collapse
Affiliation(s)
- Davinson C Anyogu
- Department of Veterinary Pathology and Microbiology, University of Nigeria, Nsukka, Enugu, 410002, Nigeria.
| | - Shodeinde V O Shoyinka
- Department of Veterinary Pathology and Microbiology, University of Nigeria, Nsukka, Enugu, 410002, Nigeria
| | - John I Ihedioha
- Department of Veterinary Pathology and Microbiology, University of Nigeria, Nsukka, Enugu, 410002, Nigeria
| |
Collapse
|
3
|
Rotureau B, Waleckx E, Jamonneau V, Solano P, Molia S, Debré P, Dellagi K, Morand S. Enhancing research integration to improve One Health actions: learning lessons from neglected tropical diseases experiences. BMJ Glob Health 2022; 7:bmjgh-2022-008881. [PMID: 35688485 PMCID: PMC9189848 DOI: 10.1136/bmjgh-2022-008881] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 05/21/2022] [Indexed: 02/05/2023] Open
Affiliation(s)
- Brice Rotureau
- Parasitology Unit, Institut Pasteur of Guinea, Conakry, Guinea .,Trypanosome Transmission Group, Institut Pasteur, Paris, France
| | - Etienne Waleckx
- INTERTRYP - IRD, CIRAD, University of Montpellier, IRD, Montpellier, France.,Autonomous University of Yucatan, CIR Hideyo Noguchi, Merida, Mexico
| | - Vincent Jamonneau
- INTERTRYP - IRD, CIRAD, University of Montpellier, IRD, Montpellier, France
| | - Philippe Solano
- INTERTRYP - IRD, CIRAD, University of Montpellier, IRD, Montpellier, France
| | - Sophie Molia
- UMR ASTRE, CIRAD, Montpellier, France.,Univ Montpellier CIRAD INRAE, Montpellier, France
| | | | | | - Serge Morand
- CNRS MIVEGEC, IRD, Montpellier University, Montpellier, France.,Faculty of Veterinary Technology, Kasetsart University, Bangkok, Thailand
| |
Collapse
|
4
|
Malatji DP. Breeding of African sheep reared under low-input/output smallholder production systems for trypanotolerance. Vet World 2022; 15:1031-1043. [PMID: 35698514 PMCID: PMC9178589 DOI: 10.14202/vetworld.2022.1031-1043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 03/11/2022] [Indexed: 11/30/2022] Open
Abstract
Trypanosomiasis is a disease caused by unicellular protozoan parasites. Small ruminants succumb to trypanosomiasis in areas of high tsetse fly challenge, resulting in serious economic loss often to farmers in low-input smallholder systems. At present, trypanosomiasis is treated with trypanocidal drugs, but access to these can be limited, and increasing parasite resistance raises questions about their efficacy. The development of trypanotolerance in small ruminant flocks through targeted breeding strategies is considered a sustainable and economical option for controlling African trypanosomiasis. Recently, quantitative trait loci (QTLs) associated with trypanotolerance traits in sheep have been reported. The results of these studies form the basis for more studies to identify QTLs associated with trypanosomiasis resistance, particularly in African livestock species. For example, signatures of positive selection for trypanotolerance have been identified using genome-wide single-nucleotide polymorphism data. However, there are several challenges in performing genetic analyses using data from low-input smallholder systems, including a lack of recorded pedigree and production records and the need for large sample sizes when flock sizes are often fewer than 50 animals. Breeding strategies to improve trypanotolerance should also preserve existing genetic diversity as well as minimize excessive genetic introgression by trypanosusceptible breeds. This review discusses the possibilities of breeding for trypanosome tolerance/resistance in low-input/low-output small ruminant production systems. Potential challenges are outlined, and potential available genetic resources are described as a foundation for future work.
Collapse
Affiliation(s)
- Dikeledi P. Malatji
- Department of Agriculture and Animal Health, College of Agriculture and Environmental Sciences, University of South Africa, Johannesburg, Gauteng Province, South Africa
| |
Collapse
|
5
|
Upregulation of sialyltransferases ST3Gal1 and ST6Gal1 promotes stabilization of erythrocyte mass and recovery of anemia in Trypanosoma brucei brucei-infected pigs. Res Vet Sci 2022; 145:102-108. [DOI: 10.1016/j.rvsc.2022.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 01/14/2022] [Accepted: 02/04/2022] [Indexed: 11/23/2022]
|
6
|
Free-ranging pigs identified as a multi-reservoir of Trypanosoma brucei and Trypanosoma congolense in the Vavoua area, a historical sleeping sickness focus of Côte d'Ivoire. PLoS Negl Trop Dis 2021; 15:e0010036. [PMID: 34937054 PMCID: PMC8735613 DOI: 10.1371/journal.pntd.0010036] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 01/06/2022] [Accepted: 11/28/2021] [Indexed: 12/03/2022] Open
Abstract
Background The existence of an animal reservoir of Trypanosoma brucei gambiense (T. b. gambiense), the agent of human African trypanosomiasis (HAT), may compromise the interruption of transmission targeted by World Health Organization. The aim of this study was to investigate the presence of trypanosomes in pigs and people in the Vavoua HAT historical focus where cases were still diagnosed in the early 2010’s. Methods For the human survey, we used the CATT, mini-anion exchange centrifugation technique and immune trypanolysis tests. For the animal survey, the buffy coat technique was also used as well as the PCR using Trypanosoma species specific, including the T. b. gambiense TgsGP detection using single round and nested PCRs, performed from animal blood samples and from strains isolated from subjects positive for parasitological investigations. Results No HAT cases were detected among 345 people tested. A total of 167 pigs were investigated. Free-ranging pigs appeared significantly more infected than pigs in pen. Over 70% of free-ranging pigs were positive for CATT and parasitological investigations and 27–43% were positive to trypanolysis depending on the antigen used. T. brucei was the most prevalent species (57%) followed by T. congolense (24%). Blood sample extracted DNA of T. brucei positive subjects were negative to single round TgsGP PCR. However, 1/22 and 6/22 isolated strains were positive with single round and nested TgsGP PCRs, respectively. Discussion Free-ranging pigs were identified as a multi-reservoir of T. brucei and/or T. congolense with mixed infections of different strains. This trypanosome diversity hinders the easy and direct detection of T. b. gambiense. We highlight the lack of tools to prove or exclude with certainty the presence of T. b. gambiense. This study once more highlights the need of technical improvements to explore the role of animals in the epidemiology of HAT. Significant efforts to control human African trypanosomiasis (HAT) since the 1990’s have drastically reduced the prevalence of the disease. Its elimination as a public health problem is being achieved. World Health Organization now targets the interruption of transmission for 2030. However, potential animal reservoirs of Trypanosoma brucei gambiense (T. b. gambiense), the main agent of HAT, may compromise this ambitious objective. It is the case in the Vavoua historical focus in Côte d’Ivoire where HAT cases were still diagnosed in the early 2010’s. During a study conducted in this area, we scrutinized the trypanosomes circulating in pigs and people sharing the same environment using serological, immunological, parasitological and molecular tools. No HAT cases were detected. We showed that T. brucei s.l. and T. congolense actively circulated in free-ranging pigs. Even if no tools were sensitive and specific enough to unambiguously identify T. b. gambiense directly from biological samples, six isolated strains from pigs positive for trypanosomes were amplified for TgsGP, the only currently accepted T. b. gambiense specific molecular marker. The apparent discrepancies between the presence of T. b. gambiense in pigs despite the absence of human cases is discussed. These results stress the need for an efficient “molecular toolbox” to easily detect and identify T. b. gambiense in any animal it may infect.
Collapse
|
7
|
Single nucleotide polymorphisms and copy-number variations in the Trypanosoma brucei repeat (TBR) sequence can be used to enhance amplification and genotyping of Trypanozoon strains. PLoS One 2021; 16:e0258711. [PMID: 34695154 PMCID: PMC8544829 DOI: 10.1371/journal.pone.0258711] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 10/04/2021] [Indexed: 11/19/2022] Open
Abstract
The Trypanosoma brucei repeat (TBR) is a tandem repeat sequence present on the Trypanozoon minichromosomes. Here, we report that the TBR sequence is not as homogenous as previously believed. BLAST analysis of the available T. brucei genomes reveals various TBR sequences of 177 bp and 176 bp in length, which can be sorted into two TBR groups based on a few key single nucleotide polymorphisms. Conventional and quantitative PCR with primers matched to consensus sequences that target either TBR group show substantial copy-number variations in the TBR repertoire within a collection of 77 Trypanozoon strains. We developed the qTBR, a novel PCR consisting of three primers and two probes, to simultaneously amplify target sequences from each of the two TBR groups into one single qPCR reaction. This dual probe setup offers increased analytical sensitivity for the molecular detection of all Trypanozoon taxa, in particular for T.b. gambiense and T. evansi, when compared to existing TBR PCRs. By combining the qTBR with 18S rDNA amplification as an internal standard, the relative copy-number of each TBR target sequence can be calculated and plotted, allowing for further classification of strains into TBR genotypes associated with East, West or Central Africa. Thus, the qTBR takes advantage of the single-nucleotide polymorphisms and copy number variations in the TBR sequences to enhance amplification and genotyping of all Trypanozoon strains, making it a promising tool for prevalence studies of African trypanosomiasis in both humans and animals.
Collapse
|
8
|
Aliee M, Keeling MJ, Rock KS. Modelling to explore the potential impact of asymptomatic human infections on transmission and dynamics of African sleeping sickness. PLoS Comput Biol 2021; 17:e1009367. [PMID: 34516544 PMCID: PMC8459990 DOI: 10.1371/journal.pcbi.1009367] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 09/23/2021] [Accepted: 08/20/2021] [Indexed: 01/20/2023] Open
Abstract
Gambiense human African trypanosomiasis (gHAT, sleeping sickness) is one of several neglected tropical diseases (NTDs) where there is evidence of asymptomatic human infection but there is uncertainty of the role it plays in transmission and maintenance. To explore possible consequences of asymptomatic infections, particularly in the context of elimination of transmission—a goal set to be achieved by 2030—we propose a novel dynamic transmission model to account for the asymptomatic population. This extends an established framework, basing infection progression on a number of experimental and observation gHAT studies. Asymptomatic gHAT infections include those in people with blood-dwelling trypanosomes, but no discernible symptoms, or those with parasites only detectable in skin. Given current protocols, asymptomatic infection with blood parasites may be diagnosed and treated, based on observable parasitaemia, in contrast to many other diseases for which treatment (and/or diagnosis) may be based on symptomatic infection. We construct a model in which exposed people can either progress to either asymptomatic skin-only parasite infection, which would not be diagnosed through active screening algorithms, or blood-parasite infection, which is likely to be diagnosed if tested. We add extra parameters to the baseline model including different self-cure, recovery, transmission and detection rates for skin-only or blood infections. Performing sensitivity analysis suggests all the new parameters introduced in the asymptomatic model can impact the infection dynamics substantially. Among them, the proportion of exposures resulting in initial skin or blood infection appears the most influential parameter. For some plausible parameterisations, an initial fall in infection prevalence due to interventions could subsequently stagnate even under continued screening due to the formation of a new, lower endemic equilibrium. Excluding this scenario, our results still highlight the possibility for asymptomatic infection to slow down progress towards elimination of transmission. Location-specific model fitting will be needed to determine if and where this could pose a threat. Gambiense African sleeping sickness is an infectious disease targeted for elimination of transmission by 2030. Despite this there is still some uncertainty how frequently some infected people who may not have symptoms could “self-cure” without ever having disease and whether some types of infections, such as infections only in the skin, but not the blood, could still contribute to transmission, yet go undiagnosed. To explore how problematic these asymptomatic infections could be in terms of the elimination goal, we use a mathematical model which quantitatively describes changes to infection and transmission over time and includes these different types of infection. We use results of published experimental or field studies as inputs for the model parameters governing asymptomatic infections. We examined the impact of asymptomatic infections when control interventions are put in place. Compared to a baseline model with no asymptomatics, including asymptomatic infection using plausible biological parameters can have a profound impact on transmission and slow progress towards elimination. In some instances it could be possible that even after initial decline in sleeping sickness cases, progress could stagnate without reaching the elimination goal at all, however location-specific modelling will be needed to determine if and where this could pose a threat.
Collapse
Affiliation(s)
- Maryam Aliee
- Mathematics Institute, University of Warwick, Coventry, United Kingdom
- Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, University of Warwick, Coventry, United Kingdom
- * E-mail:
| | - Matt J. Keeling
- Mathematics Institute, University of Warwick, Coventry, United Kingdom
- Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, University of Warwick, Coventry, United Kingdom
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Kat S. Rock
- Mathematics Institute, University of Warwick, Coventry, United Kingdom
- Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, University of Warwick, Coventry, United Kingdom
| |
Collapse
|
9
|
Serranito B, Taurisson-Mouret D, Harkat S, Laoun A, Ouchene-Khelifi NA, Pompanon F, Benjelloun B, Cecchi G, Thevenon S, Lenstra JA, Da Silva A. Search for Selection Signatures Related to Trypanosomosis Tolerance in African Goats. Front Genet 2021; 12:715732. [PMID: 34413881 PMCID: PMC8369930 DOI: 10.3389/fgene.2021.715732] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 06/28/2021] [Indexed: 12/13/2022] Open
Abstract
Livestock is heavily affected by trypanosomosis in Africa. Through strong selective pressure, several African indigenous breeds of cattle and small ruminants have acquired varying degrees of tolerance against this disease. In this study, we combined LFMM and PCAdapt for analyzing two datasets of goats from West-Central Africa and East Africa, respectively, both comprising breeds with different assumed levels of trypanotolerance. The objectives were (i) to identify molecular signatures of selection related to trypanotolerance; and (ii) to guide an optimal sampling for subsequent studies. From 33 identified signatures, 18 had been detected previously in the literature as being mainly associated with climatic adaptations. The most plausible signatures of trypanotolerance indicate the genes DIS3L2, COPS7B, PD5A, UBE2K, and UBR1. The last gene is of particular interest since previous literature has already identified E3-ubiquitin ligases as playing a decisive role in the immune response. For following-up on these findings, the West-Central African area appears particularly relevant because of (i) a clear parasitic load gradient related to a humidity gradient, and (ii) still restricted admixture levels between goat breeds. This study illustrates the importance of protecting local breeds, which have retained unique allelic combinations conferring their remarkable adaptations.
Collapse
Affiliation(s)
- Bruno Serranito
- Museum National d’Histoire Naturelle, CRESCO, Dinard, France
- University of Limoges, PEREINE, E2LIM, Limoges, France
| | | | - Sahraoui Harkat
- Science Veterinary Institute, University of Blida, Blida, Algeria
| | | | | | - François Pompanon
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LECA, Grenoble, France
| | - Badr Benjelloun
- National Institute of Agronomic Research, Regional Centre of Agronomic Research, Beni-Mellal, Morocco
| | - Giuliano Cecchi
- Food and Agriculture Organization of the United Nations, Animal Production and Health Division, Rome, Italy
| | - Sophie Thevenon
- CIRAD, UMR INTERTRYP, Montpellier, France
- INTERTRYP, University of Montpellier, CIRAD, IRD, Montpellier, France
| | | | - Anne Da Silva
- University of Limoges, PEREINE, E2LIM, Limoges, France
| |
Collapse
|
10
|
Camara M, Soumah AM, Ilboudo H, Travaillé C, Clucas C, Cooper A, Kuispond Swar NR, Camara O, Sadissou I, Calvo Alvarez E, Crouzols A, Bart JM, Jamonneau V, Camara M, MacLeod A, Bucheton B, Rotureau B. Extravascular Dermal Trypanosomes in Suspected and Confirmed Cases of gambiense Human African Trypanosomiasis. Clin Infect Dis 2021; 73:12-20. [PMID: 32638003 PMCID: PMC8246823 DOI: 10.1093/cid/ciaa897] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 06/25/2020] [Indexed: 11/18/2022] Open
Abstract
Background The diagnosis of gambiense human African trypanosomiasis (gHAT) typically involves 2 steps: a serological screen, followed by the detection of living trypanosome parasites in the blood or lymph node aspirate. Live parasites can, however, remain undetected in some seropositive individuals, who, we hypothesize, are infected with Trypanosoma brucei gambiense parasites in their extravascular dermis. Methods To test this hypothesis, we conducted a prospective observational cohort study in the gHAT focus of Forecariah, Republic of Guinea. Of the 5417 subjects serologically screened for gHAT, 66 were enrolled into our study and underwent a dermatological examination. At enrollment, 11 seronegative, 8 unconfirmed seropositive, and 18 confirmed seropositive individuals had blood samples and skin biopsies taken and examined for trypanosomes by molecular and immunohistological methods. Results In seropositive individuals, dermatological symptoms were significantly more frequent, relative to seronegative controls. T.b. gambiense parasites were present in the blood of all confirmed cases (n = 18) but not in unconfirmed seropositive individuals (n = 8). However, T. brucei parasites were detected in the extravascular dermis of all unconfirmed seropositive individuals and all confirmed cases. Skin biopsies of all treated cases and most seropositive untreated individuals progressively became negative for trypanosomes 6 and 20 months later. Conclusions Our results highlight the skin as a potential reservoir for African trypanosomes, with implications for our understanding of this disease’s epidemiology in the context of its planned elimination and underlining the skin as a novel target for gHAT diagnostics.
Collapse
Affiliation(s)
- Mariame Camara
- Programme National de Lutte Contre la Trypanosomiase Humaine Africaine, Ministère de la Santé, Conakry, Guinea
| | - Alseny M'mah Soumah
- Programme National de Lutte Contre la Trypanosomiase Humaine Africaine, Ministère de la Santé, Conakry, Guinea.,Service de Dermatologie, Hôpital de Donka,Conakry, Guinea
| | - Hamidou Ilboudo
- Programme National de Lutte Contre la Trypanosomiase Humaine Africaine, Ministère de la Santé, Conakry, Guinea.,Institut de Recherche en Sciences de la Santé (IRSS)-Unité de Recherche Clinique de Nanoro (URCN), Nanoro, Burkina-Faso.,Institut de Recherche pour le Développement, Unité Mixte de Recherche Institut de Recherche pour le Développement (IRD)-CIRAD 177 InterTryp, Campus International de Baillarguet, Montpellier, France
| | - Christelle Travaillé
- Trypanosome Transmission Group, Trypanosome Cell Biology Unit, Institut National de la Santé et de la Recherche Médicale (INSERM) U1201 and Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Caroline Clucas
- Wellcome Centre for Integrative Parasitology, College of Medical, Veterinary, and Life Sciences, Henry Wellcome Building for Comparative Medical Sciences, Glasgow, Scotland, United Kingdom
| | - Anneli Cooper
- Wellcome Centre for Integrative Parasitology, College of Medical, Veterinary, and Life Sciences, Henry Wellcome Building for Comparative Medical Sciences, Glasgow, Scotland, United Kingdom
| | - Nono-Raymond Kuispond Swar
- Wellcome Centre for Integrative Parasitology, College of Medical, Veterinary, and Life Sciences, Henry Wellcome Building for Comparative Medical Sciences, Glasgow, Scotland, United Kingdom.,Department of Parasitology, National Institute of Biomedical Research (INRB), Kinshasa, Democratic Republic of the Congo
| | - Oumou Camara
- Programme National de Lutte Contre la Trypanosomiase Humaine Africaine, Ministère de la Santé, Conakry, Guinea
| | - Ibrahim Sadissou
- Institut de Recherche pour le Développement, Unité Mixte de Recherche Institut de Recherche pour le Développement (IRD)-CIRAD 177 InterTryp, Campus International de Baillarguet, Montpellier, France
| | - Estefania Calvo Alvarez
- Trypanosome Transmission Group, Trypanosome Cell Biology Unit, Institut National de la Santé et de la Recherche Médicale (INSERM) U1201 and Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Aline Crouzols
- Trypanosome Transmission Group, Trypanosome Cell Biology Unit, Institut National de la Santé et de la Recherche Médicale (INSERM) U1201 and Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Jean-Mathieu Bart
- Institut de Recherche pour le Développement, Unité Mixte de Recherche Institut de Recherche pour le Développement (IRD)-CIRAD 177 InterTryp, Campus International de Baillarguet, Montpellier, France
| | - Vincent Jamonneau
- Institut de Recherche pour le Développement, Unité Mixte de Recherche Institut de Recherche pour le Développement (IRD)-CIRAD 177 InterTryp, Campus International de Baillarguet, Montpellier, France
| | - Mamadou Camara
- Programme National de Lutte Contre la Trypanosomiase Humaine Africaine, Ministère de la Santé, Conakry, Guinea
| | - Annette MacLeod
- Wellcome Centre for Integrative Parasitology, College of Medical, Veterinary, and Life Sciences, Henry Wellcome Building for Comparative Medical Sciences, Glasgow, Scotland, United Kingdom
| | - Bruno Bucheton
- Programme National de Lutte Contre la Trypanosomiase Humaine Africaine, Ministère de la Santé, Conakry, Guinea.,Institut de Recherche pour le Développement, Unité Mixte de Recherche Institut de Recherche pour le Développement (IRD)-CIRAD 177 InterTryp, Campus International de Baillarguet, Montpellier, France
| | - Brice Rotureau
- Trypanosome Transmission Group, Trypanosome Cell Biology Unit, Institut National de la Santé et de la Recherche Médicale (INSERM) U1201 and Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| |
Collapse
|
11
|
Salivarian Trypanosomes Have Adopted Intricate Host-Pathogen Interaction Mechanisms That Ensure Survival in Plain Sight of the Adaptive Immune System. Pathogens 2021; 10:pathogens10060679. [PMID: 34072674 PMCID: PMC8229994 DOI: 10.3390/pathogens10060679] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/24/2021] [Accepted: 05/28/2021] [Indexed: 12/21/2022] Open
Abstract
Salivarian trypanosomes are extracellular parasites affecting humans, livestock and game animals. Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense are human infective sub-species of T. brucei causing human African trypanosomiasis (HAT—sleeping sickness). The related T. b. brucei parasite lacks the resistance to survive in human serum, and only inflicts animal infections. Animal trypanosomiasis (AT) is not restricted to Africa, but is present on all continents. T. congolense and T. vivax are the most widespread pathogenic trypanosomes in sub-Saharan Africa. Through mechanical transmission, T. vivax has also been introduced into South America. T. evansi is a unique animal trypanosome that is found in vast territories around the world and can cause atypical human trypanosomiasis (aHT). All salivarian trypanosomes are well adapted to survival inside the host’s immune system. This is not a hostile environment for these parasites, but the place where they thrive. Here we provide an overview of the latest insights into the host-parasite interaction and the unique survival strategies that allow trypanosomes to outsmart the immune system. In addition, we review new developments in treatment and diagnosis as well as the issues that have hampered the development of field-applicable anti-trypanosome vaccines for the implementation of sustainable disease control.
Collapse
|
12
|
Vanvanhossou SFU, Koura IB, Dossa LH. The implications of herd entrustment practice for the sustainable use of cattle genetic resources in the (agro)-pastoral systems of West Africa: A case study from Benin. PASTORALISM 2021. [DOI: 10.1186/s13570-020-00189-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractWest African (agro)-pastoralists have been increasingly using extra-household labour for the management of their cattle herds. This paper seeks to identify the factors influencing cattle owners’ decision to entrust their animals and to analyse the effects of the entrustment practice on the management and sustainable use of the animal genetic diversity within herds. Two hundred and eleven cattle farmers, including absentee-owners (n = 90) who entrusted their animals to professional herders, and owner-managers (n = 121) who look themselves after their cattle, were randomly selected and surveyed in Boukombe district in northwest Benin, the origin of the West African shorthorn Somba cattle breed. Households' socio-economic data and information on herds’ characteristics and management practices were collected using semi-structured questionnaires. The binary logistic regression technique was used to predict the adoption of entrustment by a given farmer in function of his herd’s and household's socio-economic characteristics. Effective population sizes and inbreeding rates for the communal non-entrusted and entrusted Somba populations were estimated and compared. The results revealed that the mode of acquisition of the initial stock, the total livestock units owned and the farmer’s ethnicity were the most important determinants of entrustment. The Somba indigenous cattle breed was threatened in entrusted herds by indiscriminate cross-breeding with Zebus. However, the non-entrusted population appeared to be more exposed to high inbreeding risks. While entrustment represents a good alternative for the efficient use of family labour, adequate strategies are needed to support this practice and encourage herd managers to adopt improved husbandry practices and sound breeding strategies.
Collapse
|
13
|
Vanvanhossou SFU, Scheper C, Dossa LH, Yin T, Brügemann K, König S. A multi-breed GWAS for morphometric traits in four Beninese indigenous cattle breeds reveals loci associated with conformation, carcass and adaptive traits. BMC Genomics 2020; 21:783. [PMID: 33176675 PMCID: PMC7656759 DOI: 10.1186/s12864-020-07170-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 10/20/2020] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Specific adaptive features including disease resistance and growth abilities in harsh environments are attributed to indigenous cattle breeds of Benin, but these breeds are endangered due to crossbreeding. So far, there is a lack of systematic trait recording, being the basis for breed characterizations, and for structured breeding program designs aiming on conservation. Bridging this gap, own phenotyping for morphological traits considered measurements for height at withers (HAW), sacrum height (SH), heart girth (HG), hip width (HW), body length (BL) and ear length (EL), including 449 cattle from the four indigenous Benin breeds Lagune, Somba, Borgou and Pabli. In order to utilize recent genomic tools for breed characterizations and genetic evaluations, phenotypes for novel traits were merged with high-density SNP marker data. Multi-breed genetic parameter estimations and genome-wide association studies (GWAS) for the six morphometric traits were carried out. Continuatively, we aimed on inferring genomic regions and functional loci potentially associated with conformation, carcass and adaptive traits. RESULTS SNP-based heritability estimates for the morphometric traits ranged between 0.46 ± 0.14 (HG) and 0.74 ± 0.13 (HW). Phenotypic and genetic correlations ranged from 0.25 ± 0.05 (HW-BL) to 0.89 ± 0.01 (HAW-SH), and from 0.14 ± 0.10 (HW-BL) to 0.85 ± 0.02 (HAW-SH), respectively. Three genome-wide and 25 chromosome-wide significant SNP positioned on different chromosomes were detected, located in very close chromosomal distance (±25 kb) to 15 genes (or located within the genes). The genes PIK3R6 and PIK3R1 showed direct functional associations with height and body size. We inferred the potential candidate genes VEPH1, CNTNAP5, GYPC for conformation, growth and carcass traits including body weight and body fat deposition. According to their functional annotations, detected potential candidate genes were associated with stress or immune response (genes PTAFR, PBRM1, ADAMTS12) and with feed efficiency (genes MEGF11 SLC16A4, CCDC117). CONCLUSIONS Accurate measurements contributed to large SNP heritabilities for some morphological traits, even for a small mixed-breed sample size. Multi-breed GWAS detected different loci associated with conformation or carcass traits. The identified potential candidate genes for immune response or feed efficiency indicators reflect the evolutionary development and adaptability features of the breeds.
Collapse
Affiliation(s)
| | - Carsten Scheper
- Institute of Animal Breeding and Genetics, Justus-Liebig-University Gießen, Gießen, Germany
| | - Luc Hippolyte Dossa
- School of Science and Technics of Animal Production, Faculty of Agricultural Sciences, University of Abomey-Calavi, Cotonou, Benin
| | - Tong Yin
- Institute of Animal Breeding and Genetics, Justus-Liebig-University Gießen, Gießen, Germany
| | - Kerstin Brügemann
- Institute of Animal Breeding and Genetics, Justus-Liebig-University Gießen, Gießen, Germany
| | - Sven König
- Institute of Animal Breeding and Genetics, Justus-Liebig-University Gießen, Gießen, Germany.
| |
Collapse
|
14
|
Egbe-Nwiyi TN, Abalaka SE, Sani NA, Tenuche OZ, Idoko IS. Individual and combined anti-trypanosomal effects of arteether and diminazene aceturate in the treatment of experimental Trypanosoma brucei brucei infection in rats. Vet World 2020; 13:1858-1862. [PMID: 33132597 PMCID: PMC7566267 DOI: 10.14202/vetworld.2020.1858-1862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 07/20/2020] [Indexed: 12/05/2022] Open
Abstract
AIM Trypanosomosis is a vital protozoan disease of man and animals with devastating consequences in the tropical parts of the world, necessitating the investigation of the effects of diminazene aceturate (DA) and arteether (AR) on Trypanosoma brucei brucei experimental infection in rats. MATERIALS AND METHODS We used a total of 98 rats, which were divided into 14 groups (A-N) of seven rats each over 36 days after acclimatizing them. We administered 1×106 trypanosomes to the infected groups (B-N) with Group A as the unexposed control rats. Groups C-F became the infected and treated rats with 3.5 mg/kg, 7.0 mg/kg, 10.5 mg/kg, and 14.0 mg/kg of DA while Groups G-J became the infected and treated rats with 0.01 ml/kg, 0.02 ml/kg, 0.03 ml/kg, and 0.04 ml/kg of AR. Groups K-N became infected and treated rats with DA and AR combinations at similar doses. RESULTS Parasitemia suppression occurred in Groups G-J only but became cleared in Groups C-F and K-N. Survival time varied significantly (p<0.05) between Group B and the other infected groups. We recorded anemia in all the infected rats while significant (p<0.05) splenomegaly and hepatomegaly occurred in Groups G-J only compared to the other groups. CONCLUSION AR did not inhibit or potentiate the anti-trypanosomal efficacy of DA, and therefore, it is comparatively less effective in combating T. brucei infection at the present doses and treatment regimen.
Collapse
Affiliation(s)
- Tobias Nnia Egbe-Nwiyi
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, University of Abuja, Abuja, Nigeria
| | - Samson Eneojo Abalaka
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, University of Abuja, Abuja, Nigeria
| | - Nuhu Abdulazeez Sani
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, University of Abuja, Abuja, Nigeria
| | - Oremeyi Zainab Tenuche
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, University of Abuja, Abuja, Nigeria
| | - Idoko Sunday Idoko
- Department of Veterinary Pathology, Faculty of Veterinary Medicine, University of Abuja, Abuja, Nigeria
| |
Collapse
|
15
|
Raftery AG, Jallow S, Coultous RM, Rodgers J, Sutton DGM. Variation in disease phenotype is marked in equine trypanosomiasis. Parasit Vectors 2020; 13:148. [PMID: 32199454 PMCID: PMC7085162 DOI: 10.1186/s13071-020-04020-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 03/16/2020] [Indexed: 11/19/2022] Open
Abstract
Background Equine trypanosomiasis is a severe and prevalent disease that has the greatest impact globally upon working equids due to its distribution across lower income countries. Morbidity and mortality rates are high; disease management strategies in endemic regions are ineffective and cost prohibitive. Individual variation in disease phenotype in other species suggests host factors could reveal novel treatment and control targets but has not been investigated in equids. Methods A prospective clinical evaluation of equines presenting for a free veterinary examination was performed in hyperendemic villages in The Gambia. Age, body condition score and body weight were estimated by validated methods, and haematocrit and total protein concentration measured. Animals fulfilling 2 out of 5 clinical inclusion criteria (anaemia, poor body condition, pyrexia, history of abortion, oedema) for a diagnosis of trypanosomiasis received trypanocidal treatment with follow-up at 1 and 2 weeks. Blood samples underwent PCR analysis with specific Trypanosoma spp. primers and results were compared to the subject’s clinical and clinicopathological features. A mixed effects generalised linear model was generated to evaluate the association of infection status with degree of pyrexia and anaemia. Results Morbidity was high within examined (n = 641) and selected (n = 247) study populations. PCR status was not associated with a defined disease phenotype; there was intra- and inter-species variability. Donkeys were more frequently Trypanosoma spp.-positive (P < 0.001) and febrile (P < 0.001) than horses, but infected horses were more anaemic (P < 0.001), and in poorer body condition (P < 0.001) than donkeys. Sex was correlated to disease phenotype: males were more anaemic (P = 0.03) and febrile (P < 0.001). Haemoparasite co-infections were more common than a single infection. Conclusions There was evidence of diversity in trypanosomiasis clinical signs plus variable disease phenotypes within equid subpopulations that warrant further investigation. The complex co-infection profile of field cases requires greater consideration to optimise disease management.![]()
Collapse
Affiliation(s)
- Alexandra G Raftery
- The Weipers Centre Equine Hospital, Large Animal Clinical Sciences and Public Health, School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bearsden Road, Glasgow, UK.
| | - Saloum Jallow
- Gambia Horse and Donkey Trust, Sambel Kunda, Central River District, The Gambia
| | - Robert M Coultous
- Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Jean Rodgers
- Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - David G M Sutton
- The Weipers Centre Equine Hospital, Large Animal Clinical Sciences and Public Health, School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Bearsden Road, Glasgow, UK
| |
Collapse
|
16
|
Magez S, Pinto Torres JE, Obishakin E, Radwanska M. Infections With Extracellular Trypanosomes Require Control by Efficient Innate Immune Mechanisms and Can Result in the Destruction of the Mammalian Humoral Immune System. Front Immunol 2020; 11:382. [PMID: 32218784 PMCID: PMC7078162 DOI: 10.3389/fimmu.2020.00382] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 02/18/2020] [Indexed: 12/17/2022] Open
Abstract
Salivarian trypanosomes are extracellular parasites that affect humans, livestock, and game animals around the world. Through co-evolution with the mammalian immune system, trypanosomes have developed defense mechanisms that allow them to thrive in blood, lymphoid vessels, and tissue environments such as the brain, the fat tissue, and testes. Trypanosomes have developed ways to circumvent antibody-mediated killing and block the activation of the lytic arm of the complement pathway. Hence, this makes the innate immune control of the infection a crucial part of the host-parasite interaction, determining infection susceptibility, and parasitemia control. Indeed, trypanosomes use a combination of several independent mechanisms to avoid clearance by the humoral immune system. First, perpetuated antigenic variation of the surface coat allows to escape antibody-mediated elimination. Secondly, when antibodies bind to the coat, they are efficiently transported toward the endocytosis pathway, where they are removed from the coat proteins. Finally, trypanosomes engage in the active destruction of the mammalian humoral immune response. This provides them with a rescue solution in case antigenic variation does not confer total immunological invisibility. Both antigenic variation and B cell destruction pose significant hurdles for the development of anti-trypanosome vaccine strategies. However, developing total immune escape capacity and unlimited growth capabilities within a mammalian host is not beneficial for any parasite, as it will result in the accelerated death of the host itself. Hence, trypanosomes have acquired a system of quorum sensing that results in density-dependent population growth arrest in order to prevent overpopulating the host. The same system could possibly sense the infection-associated host tissue damage resulting from inflammatory innate immune responses, in which case the quorum sensing serves to prevent excessive immunopathology and as such also promotes host survival. In order to put these concepts together, this review summarizes current knowledge on the interaction between trypanosomes and the mammalian innate immune system, the mechanisms involved in population growth regulation, antigenic variation and the immuno-destructive effect of trypanosomes on the humoral immune system. Vaccine trials and a discussion on the role of innate immune modulation in these trials are discussed at the end.
Collapse
Affiliation(s)
- Stefan Magez
- Laboratory for Biomedical Research, Ghent University Global Campus, Incheon, South Korea.,Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium.,Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | | | - Emmanuel Obishakin
- Laboratory for Biomedical Research, Ghent University Global Campus, Incheon, South Korea.,Biotechnology Division, National Veterinary Research Institute, Vom, Nigeria
| | - Magdalena Radwanska
- Laboratory for Biomedical Research, Ghent University Global Campus, Incheon, South Korea.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| |
Collapse
|
17
|
Peptide-based vaccine successfully induces protective immunity against canine visceral leishmaniasis. NPJ Vaccines 2019; 4:49. [PMID: 31815006 PMCID: PMC6884440 DOI: 10.1038/s41541-019-0144-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 11/06/2019] [Indexed: 12/27/2022] Open
Abstract
Dogs are the main reservoir of zoonotic visceral leishmaniasis. Vaccination is a promising approach to help control leishmaniasis and to interrupt transmission of the Leishmania parasite. The promastigote surface antigen (PSA) is a highly immunogenic component of Leishmania excretory/secretory products. A vaccine based on three peptides derived from the carboxy-terminal part of Leishmania amazonensis PSA and conserved among Leishmania species, formulated with QA-21 as adjuvant, was tested on naive Beagle dogs in a preclinical trial. Four months after the full course of vaccination, dogs were experimentally infected with Leishmania infantum promastigotes. Immunization of dogs with peptide-based vaccine conferred immunity against experimental infection with L. infantum. Evidence for macrophage nitric oxide production and anti-leishmanial activity associated with IFN-γ production by lymphocytes was only found in the vaccinated group. An increase in specific IgG2 antibodies was also measured in vaccinated dogs from 2 months after immunization. Additionally, after challenge with L. infantum, the parasite burden was significantly lower in vaccinated dogs than in the control group. These data strongly suggest that this peptide-based vaccine candidate generated cross-protection against zoonotic leishmaniasis by inducing a Th1-type immune response associated with production of specific IgG2 antibodies. This preclinical trial including a peptide-based vaccine against leishmaniasis clearly demonstrates effective protection in a natural host. This approach deserves further investigation to enhance the immunogenicity of the peptides and to consider the possible engineering of a vaccine targeting several Leishmania species. Leishmaniasis, caused by the protozoan parasite Leishmania, can present in different forms depending on the infecting species. Visceral leishmaniasis is associated with migration of the parasite, in this case Leishmania infantum, to various organs and can infect both humans and canids. Here Rachel Bras-Gonçalves and colleagues test a Leishmania vaccine for dogs as they are the main reservoir for this zoonotic disease. The vaccine is based on the abundant immunogenic component of Leishmania excretory/secretory product, promastigote surface antigen (PSA); specifically, three peptides from the carboxyl-terminal of PSA, which is conserved in Leishmania species. Uninfected Beagle dogs were immunized with QA-21 as an adjuvant, and no local or systemic adverse reactions were observed. Four months later after three doses of the vaccine, dogs were infected with L. infantum promastigotes. Vaccination provided immunity with reduced parasite burden and this was associated with macrophage anti-leishmanial activity, increased IFN-y and nitric oxide production and increased Leishmania-specific IgG2 antibodies.
Collapse
|
18
|
Mekonnen YA, Gültas M, Effa K, Hanotte O, Schmitt AO. Identification of Candidate Signature Genes and Key Regulators Associated With Trypanotolerance in the Sheko Breed. Front Genet 2019; 10:1095. [PMID: 31803229 PMCID: PMC6872528 DOI: 10.3389/fgene.2019.01095] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 10/11/2019] [Indexed: 12/23/2022] Open
Abstract
African animal trypanosomiasis (AAT) is caused by a protozoan parasite that affects the health of livestock. Livestock production in Ethiopia is severely hampered by AAT and various controlling measures were not successful to eradicate the disease. AAT affects the indigenous breeds in varying degrees. However, the Sheko breed shows better trypanotolerance than other breeds. The tolerance attributes of Sheko are believed to be associated with its taurine genetic background but the genetic controls of these tolerance attributes of Sheko are not well understood. In order to investigate the level of taurine background in the genome, we compare the genome of Sheko with that of 11 other African breeds. We find that Sheko has an admixed genome composed of taurine and indicine ancestries. We apply three methods: (i) The integrated haplotype score (iHS), (ii) the standardized log ratio of integrated site specific extended haplotype homozygosity between populations (Rsb), and (iii) the composite likelihood ratio (CLR) method to discover selective sweeps in the Sheko genome. We identify 99 genomic regions harboring 364 signature genes in Sheko. Out of the signature genes, 15 genes are selected based on their biological importance described in the literature. We also identify 13 overrepresented pathways and 10 master regulators in Sheko using the TRANSPATH database in the geneXplain platform. Most of the pathways are related with oxidative stress responses indicating a possible selection response against the induction of oxidative stress following trypanosomiasis infection in Sheko. Furthermore, we present for the first time the importance of master regulators involved in trypanotolerance not only for the Sheko breed but also in the context of cattle genomics. Our finding shows that the master regulator Caspase is a key protease which plays a major role for the emergence of adaptive immunity in harmony with the other master regulators. These results suggest that designing and implementing genetic intervention strategies is necessary to improve the performance of susceptible animals. Moreover, the master regulatory analysis suggests potential candidate therapeutic targets for the development of new drugs for trypanosomiasis treatment.
Collapse
Affiliation(s)
- Yonatan Ayalew Mekonnen
- Breeding Informatics Group, Department of Animal Sciences, University of Göttingen, Göttingen, Germany
| | - Mehmet Gültas
- Breeding Informatics Group, Department of Animal Sciences, University of Göttingen, Göttingen, Germany.,Center for Integrated Breeding Research (CiBreed), University of Göttingen, Göttingen, Germany
| | - Kefena Effa
- Animal Biosciences, National Program Coordinator for African Dairy Genetic Gain, International Livestock Research Institute (ILRI), Addis Ababa, Ethiopia
| | - Olivier Hanotte
- Cells, Organisms amd Molecular Genetics, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom.,LiveGene, International Livestock Research Institute (ILRI), Addis Ababa, Ethiopia
| | - Armin O Schmitt
- Breeding Informatics Group, Department of Animal Sciences, University of Göttingen, Göttingen, Germany.,Center for Integrated Breeding Research (CiBreed), University of Göttingen, Göttingen, Germany
| |
Collapse
|
19
|
Rock KS, Ndeffo-Mbah ML, Castaño S, Palmer C, Pandey A, Atkins KE, Ndung'u JM, Hollingsworth TD, Galvani A, Bever C, Chitnis N, Keeling MJ. Assessing Strategies Against Gambiense Sleeping Sickness Through Mathematical Modeling. Clin Infect Dis 2019; 66:S286-S292. [PMID: 29860287 PMCID: PMC5982708 DOI: 10.1093/cid/ciy018] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Background Control of gambiense sleeping sickness relies predominantly on passive and active screening of people, followed by treatment. Methods Mathematical modeling explores the potential of 3 complementary interventions in high- and low-transmission settings. Results Intervention strategies that included vector control are predicted to halt transmission most quickly. Targeted active screening, with better and more focused coverage, and enhanced passive surveillance, with improved access to diagnosis and treatment, are both estimated to avert many new infections but, when used alone, are unlikely to halt transmission before 2030 in high-risk settings. Conclusions There was general model consensus in the ranking of the 3 complementary interventions studied, although with discrepancies between the quantitative predictions due to differing epidemiological assumptions within the models. While these predictions provide generic insights into improving control, the most effective strategy in any situation depends on the specific epidemiology in the region and the associated costs.
Collapse
Affiliation(s)
- Kat S Rock
- Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, Coventry, United Kingdom.,School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | | | - Soledad Castaño
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Switzerland.,University of Basel, Switzerland
| | - Cody Palmer
- Institute of Disease Modeling, Bellevue, Washington
| | - Abhishek Pandey
- Yale School of Public Health, Yale University, New Haven, Connecticut
| | - Katherine E Atkins
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, United Kingdom.,Centre for Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, United Kingdom
| | | | - T Déirdre Hollingsworth
- Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, Coventry, United Kingdom.,School of Life Sciences, University of Warwick, Coventry, United Kingdom.,Mathematics Institute, University of Warwick, Coventry, United Kingdom
| | - Alison Galvani
- Yale School of Public Health, Yale University, New Haven, Connecticut
| | | | - Nakul Chitnis
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Switzerland.,University of Basel, Switzerland
| | - Matt J Keeling
- Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, Coventry, United Kingdom.,School of Life Sciences, University of Warwick, Coventry, United Kingdom.,Mathematics Institute, University of Warwick, Coventry, United Kingdom
| |
Collapse
|
20
|
Marshall K, Gibson JP, Mwai O, Mwacharo JM, Haile A, Getachew T, Mrode R, Kemp SJ. Livestock Genomics for Developing Countries – African Examples in Practice. Front Genet 2019. [DOI: 10.10.3389/fgene.2019.00297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
|
21
|
Marshall K, Gibson JP, Mwai O, Mwacharo JM, Haile A, Getachew T, Mrode R, Kemp SJ. Livestock Genomics for Developing Countries - African Examples in Practice. Front Genet 2019; 10:297. [PMID: 31105735 PMCID: PMC6491883 DOI: 10.3389/fgene.2019.00297] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 03/19/2019] [Indexed: 01/17/2023] Open
Abstract
African livestock breeds are numerous and diverse, and typically well adapted to the harsh environment conditions under which they perform. They have been used over centuries to provide livelihoods as well as food and nutritional security. However, African livestock systems are dynamic, with many small- and medium-scale systems transforming, to varying degrees, to become more profitable. In these systems the women and men livestock keepers are often seeking new livestock breeds or genotypes - typically those that increase household income through having enhanced productivity in comparison to traditional breeds while maintaining adaptedness. In recent years genomic approaches have started to be utilized in the identification and development of such breeds, and in this article we describe a number of examples to this end from sub-Saharan Africa. These comprise case studies on: (a) dairy cattle in Kenya and Senegal, as well as sheep in Ethiopia, where genomic approaches aided the identification of the most appropriate breed-type for the local productions systems; (b) a cross-breeding program for dairy cattle in East Africa incorporating genomic selection as well as other applications of genomics; (c) ongoing work toward creating a new cattle breed for East Africa that is both productive and resistant to trypanosomiasis; and (d) the use of African cattle as resource populations to identify genomic variants of economic or ecological significance, including a specific case where the discovery data was from a community based breeding program for small ruminants in Ethiopia. Lessons learnt from the various case studies are highlighted, and the concluding section of the paper gives recommendations for African livestock systems to increasingly capitalize on genomic technologies.
Collapse
Affiliation(s)
- Karen Marshall
- Livestock Genetics Program, International Livestock Research Institute, Nairobi, Kenya
- Centre for Tropical Livestock Genetics and Health, Nairobi, Kenya
| | - John P. Gibson
- School of Environmental and Rural Science, University of New England, Armidale, NSW, Australia
| | - Okeyo Mwai
- Livestock Genetics Program, International Livestock Research Institute, Nairobi, Kenya
| | - Joram M. Mwacharo
- Small Ruminant Breeding and Genomics Group, International Center for Agricultural Research in the Dry Areas, Addis Ababa, Ethiopia
| | - Aynalem Haile
- Small Ruminant Breeding and Genomics Group, International Center for Agricultural Research in the Dry Areas, Addis Ababa, Ethiopia
| | - Tesfaye Getachew
- Small Ruminant Breeding and Genomics Group, International Center for Agricultural Research in the Dry Areas, Addis Ababa, Ethiopia
| | - Raphael Mrode
- Livestock Genetics Program, International Livestock Research Institute, Nairobi, Kenya
- Scotland’s Rural College, Edinburgh, United Kingdom
| | - Stephen J. Kemp
- Livestock Genetics Program, International Livestock Research Institute, Nairobi, Kenya
- Centre for Tropical Livestock Genetics and Health, Nairobi, Kenya
| |
Collapse
|
22
|
Geiger A, Malele I, Abd-Alla AM, Njiokou F. Blood feeding tsetse flies as hosts and vectors of mammals-pre-adapted African Trypanosoma: current and expected research directions. BMC Microbiol 2018; 18:162. [PMID: 30470183 PMCID: PMC6251083 DOI: 10.1186/s12866-018-1281-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Research on the zoo-anthropophilic blood feeding tsetse flies' biology conducted, by different teams, in laboratory settings and at the level of the ecosystems- where also co-perpetuate African Trypanosoma- has allowed to unveil and characterize key features of tsetse flies' bacterial symbionts on which rely both (a) the perpetuation of the tsetse fly populations and (b) the completion of the developmental program of the African Trypanosoma. Transcriptomic analyses have already provided much information on tsetse fly genes as well as on genes of the fly symbiotic partners Sodalis glossinidius and Wigglesworthia, which account for the successful onset or not of the African Trypanosoma developmental program. In parallel, identification of the non- symbiotic bacterial communities hosted in the tsetse fly gut has recently been initiated: are briefly introduced those bacteria genera and species common to tsetse flies collected from distinct ecosystems, that could be further studied as potential biologicals preventing the onset of the African Trypanosoma developmental program. Finally, future work will need to concentrate on how to render tsetse flies refractory, and the best means to disseminate them in the field in order to establish an overall refractory fly population.
Collapse
Affiliation(s)
- Anne Geiger
- INTERTRYP, Institut de Recherche pour le Développement, University of Montpellier, Montpellier, France
| | - Imna Malele
- Vector and Vector Borne Diseases Institute, Majani Mapana, Off Korogwe Road, Box, 1026 Tanga, Tanzania
| | - Adly M Abd-Alla
- Insect Pest Control Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Vienna, Austria
| | - Flobert Njiokou
- Faculty of Science, University of Yaoundé I, P.O. Box 812, Yaoundé, Cameroon
| |
Collapse
|
23
|
Kaboré J, Camara O, Koffi M, Sanou D, Ilboudo H, Sakandé H, Camara M, De Meeûs T, Ravel S, Belem AMG, MacLeod A, Bucheton B, Jamonneau V, Thévenon S. Differences in pathogenicity and virulence of Trypanosoma brucei gambiense field isolates in experimentally infected Balb/C mice. INFECTION, GENETICS AND EVOLUTION : JOURNAL OF MOLECULAR EPIDEMIOLOGY AND EVOLUTIONARY GENETICS IN INFECTIOUS DISEASES 2018; 63:269-276. [PMID: 29807131 DOI: 10.1016/j.meegid.2018.05.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 05/21/2018] [Accepted: 05/22/2018] [Indexed: 11/29/2022]
Abstract
Trypanosoma brucei gambiense (T. b. gambiense) is the major causative agent of human African trypanosomiasis (HAT). A great variety of clinical outcomes have been observed in West African foci, probably due to complex host-parasite interactions. In order to separate the roles of parasite genetic diversity and host variability, we have chosen to precisely characterize the pathogenicity and virulence of T. b. gambiense field isolates in a mouse model. Thirteen T. b. gambiense strains were studied in experimental infections, with 20 Balb/C infected mice per isolate. Mice were monitored for 30 days, in which mortality, parasitemia, anemia, and weight were recorded. Mortality rate, prepatent period, and maximum parasitemia were estimated, and a survival analysis was performed to compare strain pathogenicity. Mixed models were used to assess parasitemia dynamics, weight, and changes in Packed Cell Volume (PCV). Finally, a multivariate analysis was performed to infer relationships between all variables. A large phenotypic diversity was observed. Pathogenicity was highly variable, ranging from strains that kill their host within 9 days to a non-pathogenic strain (no deaths during the experiment). Virulence was also variable, with maximum parasitemia values ranging from 42 million to 1 billion trypanosomes/ml. Reduced PCV and weight occurred in the first two weeks of the infection, with the exception of two strains. Finally, the global analysis highlighted three groups of strains: a first group with highly pathogenic strains showing an early mortality associated with a short prepatent period; a second group of highly virulent strains with intermediate pathogenicity; and a third group of isolates characterized by low pathogenicity and virulence patterns. Such biological differences could be related to the observed clinical diversity in HAT. A better understanding of the biological pathways underlying the observed phenotypic diversity could thus help to clarify the complex nature of the host-parasite interactions that determine the resistance/susceptibility status to T. brucei gambiense.
Collapse
Affiliation(s)
- Jacques Kaboré
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 01 BP 454, Bobo-Dioulasso 01, Burkina Faso; Université NAZI BONI de Bobo-Dioulasso, UFR Sciences et Techniques, 01 BP 1091, Bobo-Dioulasso 01, Burkina Faso.
| | - Oumou Camara
- Programme National de Lutte contre la THA, BP 851, Conakry, Guinea.
| | - Mathurin Koffi
- Université Jean Lorougnon Guédé, UFR Environnement, BP 150, Daloa, Côte d'Ivoire.
| | - Djénéba Sanou
- Université NAZI BONI de Bobo-Dioulasso, UFR Sciences et Techniques, 01 BP 1091, Bobo-Dioulasso 01, Burkina Faso.
| | - Hamidou Ilboudo
- Programme National de Lutte contre la THA, BP 851, Conakry, Guinea.
| | - Hassane Sakandé
- Centre International de Recherche-Développement sur l'Elevage en zone Subhumide (CIRDES), 01 BP 454, Bobo-Dioulasso 01, Burkina Faso.
| | - Mamadou Camara
- Programme National de Lutte contre la THA, BP 851, Conakry, Guinea.
| | | | - Sophie Ravel
- INTERTRYP, Univ Montpellier, CIRAD, IRD, Montpellier, France.
| | - Adrien Marie Gaston Belem
- Université NAZI BONI de Bobo-Dioulasso, UFR Sciences et Techniques, 01 BP 1091, Bobo-Dioulasso 01, Burkina Faso.
| | - Annette MacLeod
- Wellcome Center for Molecular Parasitology, University of Glasgow, 464 Bearsden Road, Glasgow G60 1QH, UK.
| | - Bruno Bucheton
- INTERTRYP, Univ Montpellier, CIRAD, IRD, Montpellier, France.
| | | | | |
Collapse
|
24
|
Stijlemans B, De Baetselier P, Magez S, Van Ginderachter JA, De Trez C. African Trypanosomiasis-Associated Anemia: The Contribution of the Interplay between Parasites and the Mononuclear Phagocyte System. Front Immunol 2018; 9:218. [PMID: 29497418 PMCID: PMC5818406 DOI: 10.3389/fimmu.2018.00218] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 01/25/2018] [Indexed: 12/16/2022] Open
Abstract
African trypanosomosis (AT) is a chronically debilitating parasitic disease of medical and economic importance for the development of sub-Saharan Africa. The trypanosomes that cause this disease are extracellular protozoan parasites that have developed efficient immune escape mechanisms to manipulate the entire host immune response to allow parasite survival and transmission. During the early stage of infection, a profound pro-inflammatory type 1 activation of the mononuclear phagocyte system (MPS), involving classically activated macrophages (i.e., M1), is required for initial parasite control. Yet, the persistence of this M1-type MPS activation in trypanosusceptible animals causes immunopathology with anemia as the most prominent pathological feature. By contrast, in trypanotolerant animals, there is an induction of IL-10 that promotes the induction of alternatively activated macrophages (M2) and collectively dampens tissue damage. A comparative gene expression analysis between M1 and M2 cells identified galectin-3 (Gal-3) and macrophage migration inhibitory factor (MIF) as novel M1-promoting factors, possibly acting synergistically and in concert with TNF-α during anemia development. While Gal-3 enhances erythrophagocytosis, MIF promotes both myeloid cell recruitment and iron retention within the MPS, thereby depriving iron for erythropoiesis. Hence, the enhanced erythrophagocytosis and suppressed erythropoiesis lead to anemia. Moreover, a thorough investigation using MIF-deficient mice revealed that the underlying mechanisms in AT-associated anemia development in trypanosusceptible and tolerant animals are quite distinct. In trypanosusceptible animals, anemia resembles anemia of inflammation, while in trypanotolerant animals’ hemodilution, mainly caused by hepatosplenomegaly, is an additional factor contributing to anemia. In this review, we give an overview of how trypanosome- and host-derived factors can contribute to trypanosomosis-associated anemia development with a focus on the MPS system. Finally, we will discuss potential intervention strategies to alleviate AT-associated anemia that might also have therapeutic potential.
Collapse
Affiliation(s)
- Benoit Stijlemans
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Myeloid Cell Immunology Laboratory, VIB Center for Inflammation Research, Brussels, Belgium
| | - Patrick De Baetselier
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Myeloid Cell Immunology Laboratory, VIB Center for Inflammation Research, Brussels, Belgium
| | - Stefan Magez
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Laboratory for Biomedical Research, Ghent University Global Campus, Incheon, South Korea
| | - Jo A Van Ginderachter
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.,Myeloid Cell Immunology Laboratory, VIB Center for Inflammation Research, Brussels, Belgium
| | - Carl De Trez
- Laboratory of Cellular and Molecular Immunology, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| |
Collapse
|
25
|
Morriswood B, Engstler M. Let's get fISSical: fast in silico synchronization as a new tool for cell division cycle analysis. Parasitology 2018; 145:196-209. [PMID: 28166845 PMCID: PMC5964468 DOI: 10.1017/s0031182017000038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/23/2016] [Accepted: 01/05/2017] [Indexed: 12/23/2022]
Abstract
Cell cycle progression is a question of fundamental biological interest. The coordinated duplication and segregation of all cellular structures and organelles is however an extremely complex process, and one which remains only partially understood even in the most intensively researched model organisms. Trypanosomes are in an unusual position in this respect - they are both outstanding model systems for fundamental questions in eukaryotic cell biology, and pathogens that are the causative agents of three of the neglected tropical diseases. As a failure to successfully complete cell division will be deleterious or lethal, analysis of the cell division cycle is of relevance both to basic biology and drug design efforts. Cell division cycle analysis is however experimentally challenging, as the analysis of phenotypes associated with it remains hypothesis-driven and therefore biased. Current methods of analysis are extremely labour-intensive, and cell synchronization remains difficult and unreliable. Consequently, there exists a need - both in basic and applied trypanosome biology - for a global, unbiased, standardized and high-throughput analysis of cell division cycle progression. In this review, the requirements - both practical and computational - for such a system are considered and compared with existing techniques for cell cycle analysis.
Collapse
Affiliation(s)
- Brooke Morriswood
- Department of Cell & Developmental Biology,University of Würzburg,Biocentre, Am Hubland, 97074 Würzburg,Germany
| | - Markus Engstler
- Department of Cell & Developmental Biology,University of Würzburg,Biocentre, Am Hubland, 97074 Würzburg,Germany
| |
Collapse
|
26
|
Volkov OA, Brockway AJ, Wring SA, Peel M, Chen Z, Phillips MA, De Brabander JK. Species-Selective Pyrimidineamine Inhibitors of Trypanosoma brucei S-Adenosylmethionine Decarboxylase. J Med Chem 2018; 61:1182-1203. [PMID: 29271204 DOI: 10.1021/acs.jmedchem.7b01654] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
New therapeutic options are needed for treatment of human African trypanosomiasis (HAT) caused by protozoan parasite Trypanosoma brucei. S-Adenosylmethionine decarboxylase (AdoMetDC) is an essential enzyme in the polyamine pathway of T. brucei. Previous attempts to target this enzyme were thwarted by the lack of brain penetration of the most advanced series. Herein, we describe a T. brucei AdoMetDC inhibitor series based on a pyrimidineamine pharmacophore that we identified by target-based high-throughput screening. The pyrimidineamines showed selectivity for T. brucei AdoMetDC over the human enzyme, inhibited parasite growth in whole-cell assay, and had good predicted blood-brain barrier penetration. The medicinal chemistry program elucidated structure-activity relationships within the series. Features of the series that were required for binding were revealed by determining the X-ray crystal structure of TbAdoMetDC bound to one analog. The pyrimidineamine series provides a novel starting point for an anti-HAT lead optimization.
Collapse
Affiliation(s)
| | | | - Stephen A Wring
- Scynexis, Inc. (now Avista Pharma Solutions) , 3501 Tricenter Boulevard, Suite C, Durham, North Carolina 27713, United States
| | - Michael Peel
- Scynexis, Inc. (now Avista Pharma Solutions) , 3501 Tricenter Boulevard, Suite C, Durham, North Carolina 27713, United States
| | | | | | | |
Collapse
|
27
|
Camara M, Ouattara E, Duvignaud A, Migliani R, Camara O, Leno M, Solano P, Bucheton B, Camara M, Malvy D. Impact of the Ebola outbreak on Trypanosoma brucei gambiense infection medical activities in coastal Guinea, 2014-2015: A retrospective analysis from the Guinean national Human African Trypanosomiasis control program. PLoS Negl Trop Dis 2017; 11:e0006060. [PMID: 29131822 PMCID: PMC5703571 DOI: 10.1371/journal.pntd.0006060] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 11/27/2017] [Accepted: 10/20/2017] [Indexed: 12/31/2022] Open
Abstract
Background The 2014–2015 Ebola outbreak massively hit Guinea. The coastal districts of Boffa, Dubreka and Forecariah, three major foci of Human African Trypanosomiasis (HAT), were particularly affected. We aimed to assess the impact of this epidemic on sleeping sickness screening and caring activities. Methodology/Principal findings We used preexisting data from the Guinean sleeping sickness control program, collected between 2012 and 2015. We described monthly: the number of persons (i) screened actively; (ii) or passively; (iii) treated for HAT; (iv) attending post-treatment follow-up visits. We compared clinical data, treatment characteristics and Disability Adjusted Life-Years (DALYs) before (February 2012 to December 2013) and during (January 2014 to October 2015) the Ebola outbreak period according to available data. Whereas 32,221 persons were actively screened from February 2012 to December 2013, before the official declaration of the first Ebola case in Guinea, no active screening campaigns could be performed during the Ebola outbreak. Following the reinforcement and extension of HAT passive surveillance system early in 2014, the number of persons tested passively by month increased from 7 to 286 between April and September 2014 and then abruptly decreased to 180 until January 2015 and to none after March 2015. 213 patients initiated HAT treatment, 154 (72%) before Ebola and 59 (28%) during the Ebola outbreak. Those initiating HAT therapy during Ebola outbreak were recruited through passive screening and diagnosed at a later stage 2 of the disease (96% vs. 55% before Ebola, p<0.0001). The proportion of patients attending the 3 months and 6 months post-treatment follow-up visits decreased from 44% to 10% (p <0.0001) and from 16% to 3% (p = 0.017) respectively. The DALYs generated before the Ebola outbreak were estimated to 48.7 (46.7–51.5) and increased up to 168.7 (162.7–174.7), 284.9 (277.1–292.8) and 466.3 (455.7–477.0) during Ebola assuming case fatality rates of 2%, 5% and 10% respectively among under-reported HAT cases. Conclusions/Significance The 2014–2015 Ebola outbreak deeply impacted HAT screening activities in Guinea. Active screening campaigns were stopped. Passive screening dramatically decreased during the Ebola period, but trends could not be compared with pre-Ebola period (data not available). Few patients were diagnosed with more advanced HAT during the Ebola period and retention rates in follow-up were lowered. The drop in newly diagnosed HAT cases during Ebola epidemic is unlikely due to a fall in HAT incidence. Even if we were unable to demonstrate it directly, it is much more probably the consequence of hampered screening activities and of the fear of the population on subsequent confirmation and linkage to care. Reinforced program monitoring, alternative control strategies and sustainable financial and human resources allocation are mandatory during post Ebola period to reduce HAT burden in Guinea. This work was conducted in coastal Guinea, the last focus in Western Africa where the transmission of Human African Trypanosomiasis (HAT) is still very active. The Guinean government and his partners are conducting HAT control activities to reduce the burden of this neglected tropical disease and, as set-up by WHO, to eliminate it as a public health problem by 2020. Unfortunately, control efforts were deeply impaired during the Ebola outbreak that stroke the country in 2014–15. The aim of the study was to evaluate the impact of this unprecedented outbreak on HAT screening and caring activities. A major impact was the interruption of all active screening activities which aim, in addition of detecting and treating patients, is to clear the human reservoir of parasite and decrease transmission. Passive surveillance and diagnosis were also severely affected due to the fear of the population to come to the endemic district confirmation and treatment facilities and to the progressive banning of using rapid test in peripheral health structures, as well as the requisition of healthcare workers and facilities for the fight against Ebola. As a consequence, only 59 HAT patients were diagnosed and treated during the Ebola outbreak (from January 2014 to October 2015) as compared to 154 before the outbreak (from February 2012 to December 2013). This potentially high number of undiagnosed human reservoir of trypanosomes may have contributed in turn to increase transmission levels. A rapid revival of HAT control activities in Guinea is thus vital in order to stay in line with the 2020 elimination goal and to avoid possible bursts of the disease.
Collapse
Affiliation(s)
- Mariame Camara
- Programme National de Lutte contre la Trypanosomiase Humaine Africaine PNLTHA-Ministère de la Santé, Conakry, République de Guinée
| | - Eric Ouattara
- Univ. Bordeaux, Inserm, Infectious Diseases in Resource Limited Countries, U1219, ISPED, Bordeaux, France
- Department of Tropical Medicine and Clinical International Health, CHU Bordeaux, Bordeaux, France
- Programme PAC-CI/ANRS Research Site, CHU Treichville, Abidjan, Côte d’Ivoire
| | - Alexandre Duvignaud
- Univ. Bordeaux, Inserm, Infectious Diseases in Resource Limited Countries, U1219, ISPED, Bordeaux, France
- Department of Tropical Medicine and Clinical International Health, CHU Bordeaux, Bordeaux, France
- Programme PAC-CI/ANRS Research Site, CHU Treichville, Abidjan, Côte d’Ivoire
- * E-mail:
| | - René Migliani
- Univ. Bordeaux, Inserm, Infectious Diseases in Resource Limited Countries, U1219, ISPED, Bordeaux, France
| | - Oumou Camara
- Programme National de Lutte contre la Trypanosomiase Humaine Africaine PNLTHA-Ministère de la Santé, Conakry, République de Guinée
| | - Mamadou Leno
- Programme National de Lutte contre la Trypanosomiase Humaine Africaine PNLTHA-Ministère de la Santé, Conakry, République de Guinée
| | | | | | - Mamadou Camara
- Programme National de Lutte contre la Trypanosomiase Humaine Africaine PNLTHA-Ministère de la Santé, Conakry, République de Guinée
| | - Denis Malvy
- Univ. Bordeaux, Inserm, Infectious Diseases in Resource Limited Countries, U1219, ISPED, Bordeaux, France
- Department of Tropical Medicine and Clinical International Health, CHU Bordeaux, Bordeaux, France
- Programme PAC-CI/ANRS Research Site, CHU Treichville, Abidjan, Côte d’Ivoire
| |
Collapse
|
28
|
Synthesis and evaluation of analogs of 5'-(((Z)-4-amino-2-butenyl)methylamino)-5'-deoxyadenosine (MDL 73811, or AbeAdo) - An inhibitor of S-adenosylmethionine decarboxylase with antitrypanosomal activity. Bioorg Med Chem 2017; 25:5433-5440. [PMID: 28807574 DOI: 10.1016/j.bmc.2017.07.063] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 07/31/2017] [Indexed: 01/18/2023]
Abstract
We describe our efforts to improve the pharmacokinetic properties of a mechanism-based suicide inhibitor of the polyamine biosynthetic enzyme S-adenosylmethionine decarboxylase (AdoMetDC), essential for the survival of the eukaryotic parasite Trypanosoma brucei responsible for Human African Trypanosomiasis (HAT). The lead compound, 5'-(((Z)-4-amino-2-butenyl)methylamino)-5'-deoxyadenosine (1, also known as MDL 73811, or AbeAdo), has curative efficacy at a low dosage in a hemolymphatic model of HAT but displayed no demonstrable effect in a mouse model of the CNS stage of HAT due to poor blood-brain barrier permeation. Therefore, we prepared and evaluated an extensive set of analogs with modifications in the aminobutenyl side chain, the 5'-amine, the ribose, and the purine fragments. Although we gained valuable structure-activity insights from this comprehensive dataset, we did not gain traction on improving the prospects for CNS penetration while retaining the potent antiparasitic activity and metabolic stability of the lead compound 1.
Collapse
|
29
|
Volkov OA, Cosner CC, Brockway AJ, Kramer M, Booker M, Zhong S, Ketcherside A, Wei S, Longgood J, McCoy M, Richardson TE, Wring SA, Peel M, Klinger JD, Posner BA, De Brabander JK, Phillips MA. Identification of Trypanosoma brucei AdoMetDC Inhibitors Using a High-Throughput Mass Spectrometry-Based Assay. ACS Infect Dis 2017; 3:512-526. [PMID: 28350440 DOI: 10.1021/acsinfecdis.7b00022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human African trypanosomiasis (HAT) is a fatal infectious disease caused by the eukaryotic pathogen Trypanosoma brucei (Tb). Available treatments are difficult to administer and have significant safety issues. S-Adenosylmethionine decarboxylase (AdoMetDC) is an essential enzyme in the parasite polyamine biosynthetic pathway. Previous attempts to develop TbAdoMetDC inhibitors into anti-HAT therapies failed due to poor brain exposure. Here, we describe a large screening campaign of two small-molecule libraries (∼400,000 compounds) employing a new high-throughput (∼7 s per sample) mass spectrometry-based assay for AdoMetDC activity. As a result of primary screening, followed by hit confirmation and validation, we identified 13 new classes of reversible TbAdoMetDC inhibitors with low-micromolar potency (IC50) against both TbAdoMetDC and T. brucei parasite cells. The majority of these compounds were >10-fold selective against the human enzyme. Importantly, compounds from four classes demonstrated high propensity to cross the blood-brain barrier in a cell monolayer assay. Biochemical analysis demonstrated that compounds from eight classes inhibited intracellular TbAdoMetDC in the parasite, although evidence for a secondary off-target component was also present. The discovery of several new TbAdoMetDC inhibitor chemotypes provides new hits for lead optimization programs aimed to deliver a novel treatment for HAT.
Collapse
Affiliation(s)
| | | | | | - Martin Kramer
- Genzyme Corp. (now Sanofi Genzyme), 153 Second Avenue, Waltham, Massachusetts 02451-1122, United States
| | - Michael Booker
- Genzyme Corp. (now Sanofi Genzyme), 153 Second Avenue, Waltham, Massachusetts 02451-1122, United States
| | | | | | | | | | | | - Thomas E. Richardson
- Scynexis, Inc. (now Avista Pharma Solutions), 3501 Tricenter Boulevard, Suite
C, Durham, North Carolina 27713, United States
| | - Stephen A. Wring
- Scynexis, Inc. (now Avista Pharma Solutions), 3501 Tricenter Boulevard, Suite
C, Durham, North Carolina 27713, United States
| | - Michael Peel
- Scynexis, Inc. (now Avista Pharma Solutions), 3501 Tricenter Boulevard, Suite
C, Durham, North Carolina 27713, United States
| | - Jeffrey D. Klinger
- Genzyme Corp. (now Sanofi Genzyme), 153 Second Avenue, Waltham, Massachusetts 02451-1122, United States
| | | | | | | |
Collapse
|
30
|
Ono Y, Saido TC, Sorimachi H. Calpain research for drug discovery: challenges and potential. Nat Rev Drug Discov 2016; 15:854-876. [PMID: 27833121 DOI: 10.1038/nrd.2016.212] [Citation(s) in RCA: 186] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Calpains are a family of proteases that were scientifically recognized earlier than proteasomes and caspases, but remain enigmatic. However, they are known to participate in a multitude of physiological and pathological processes, performing 'limited proteolysis' whereby they do not destroy but rather modulate the functions of their substrates. Calpains are therefore referred to as 'modulator proteases'. Multidisciplinary research on calpains has begun to elucidate their involvement in pathophysiological mechanisms. Therapeutic strategies targeting malfunctions of calpains have been developed, driven primarily by improvements in the specificity and bioavailability of calpain inhibitors. Here, we review the calpain superfamily and calpain-related disorders, and discuss emerging calpain-targeted therapeutic strategies.
Collapse
Affiliation(s)
- Yasuko Ono
- Calpain Project, Department of Advanced Science for Biomolecules, Tokyo Metropolitan Institute of Medical Science (IGAKUKEN), 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Hiroyuki Sorimachi
- Calpain Project, Department of Advanced Science for Biomolecules, Tokyo Metropolitan Institute of Medical Science (IGAKUKEN), 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| |
Collapse
|
31
|
Garcia HA, Ramírez OJ, Rodrigues CMF, Sánchez RG, Bethencourt AM, Del M Pérez G, Minervino AHH, Rodrigues AC, Teixeira MMG. Trypanosoma vivax in water buffalo of the Venezuelan Llanos: An unusual outbreak of wasting disease in an endemic area of typically asymptomatic infections. Vet Parasitol 2016; 230:49-55. [PMID: 27884441 DOI: 10.1016/j.vetpar.2016.10.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 10/09/2016] [Accepted: 10/14/2016] [Indexed: 10/20/2022]
Abstract
Trypanosoma vivax has been associated with asymptomatic infections in African and South American buffalo. In this study, T. vivax was analyzed in water buffalo (Bubalus bubalis) from Venezuela in a molecular survey involving 293 blood samples collected from 2006 to 2015 across the Llanos region. Results demonstrated constant infections (average 23%) during the years analyzed. In general, animals were healthy carriers of T. vivax with low levels of parasitemia and were diagnosed exclusively by TviCATL-PCR. However, an outbreak of severe acute infections mostly in dairy animals was reported during a prolonged drought affecting 30.4% of a buffalo herd (115 animals examined). During the outbreak, animals exhibiting anemia and neurological disorders developed fatal infections, and 7% of the herd died within nine months before treatment against trypanosomosis. Microsatellite locus genotyping (MLG) of T. vivax samples before and during the outbreak revealed similar genotypes, but outbreak isolates exhibited the most divergent MLG. Venezuelan samples from symptomless and sick buffalo did not share the MLGs previously detected in asymptomatic Brazilian buffalo. Trypanosoma evansi was not detected in the herd examined during the outbreak. However, as expected Babesia sp. (62.6%) and Anaplasma sp. (55.6%) infections were highly prevalent in asymptomatic buffalo in the studied areas. This is the first South American outbreak of highly lethal acute T. vivax infections in water buffalo. Our results suggest that chronically infected and asymptomatic buffalo living in areas of enzootic equilibrium can develop symptomatic/lethal disease triggered by stressful scarcity of green forage and water during long droughts, inappropriate management of herds and likely concomitant anaplasmosis and babesiosis. Altogether, these factors weaken buffalo immune defenses, allowing T. vivax to proliferate and, consequently, allowing for progression to wasting disease.
Collapse
Affiliation(s)
- Herakles A Garcia
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil, Brazil; Facultad de Ciencias Veterinarias, Universidad Central de Venezuela, Maracay, Aragua, Venezuela
| | - Oneyda J Ramírez
- Facultad de Ciencias Veterinarias, Universidad Central de Venezuela, Maracay, Aragua, Venezuela
| | - Carla M F Rodrigues
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil, Brazil
| | - Rafael G Sánchez
- Facultad de Ciencias Veterinarias, Universidad Central de Venezuela, Maracay, Aragua, Venezuela
| | - Angelica M Bethencourt
- Facultad de Ciencias Veterinarias, Universidad Central de Venezuela, Maracay, Aragua, Venezuela
| | - Gabriela Del M Pérez
- Facultad de Ciencias Veterinarias, Universidad Central de Venezuela, Maracay, Aragua, Venezuela
| | - Antonio H H Minervino
- Instituto de Biodiversidade e Floresta, Universidade Federal do Oeste do Pará, PA, Brazil
| | - Adriana C Rodrigues
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil, Brazil
| | - Marta M G Teixeira
- Departamento de Parasitologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil, Brazil.
| |
Collapse
|
32
|
Capewell P, Cren-Travaillé C, Marchesi F, Johnston P, Clucas C, Benson RA, Gorman TA, Calvo-Alvarez E, Crouzols A, Jouvion G, Jamonneau V, Weir W, Stevenson ML, O'Neill K, Cooper A, Swar NRK, Bucheton B, Ngoyi DM, Garside P, Rotureau B, MacLeod A. The skin is a significant but overlooked anatomical reservoir for vector-borne African trypanosomes. eLife 2016; 5. [PMID: 27653219 PMCID: PMC5065312 DOI: 10.7554/elife.17716] [Citation(s) in RCA: 178] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 09/12/2016] [Indexed: 12/16/2022] Open
Abstract
The role of mammalian skin in harbouring and transmitting arthropod-borne protozoan parasites has been overlooked for decades as these pathogens have been regarded primarily as blood-dwelling organisms. Intriguingly, infections with low or undetected blood parasites are common, particularly in the case of Human African Trypanosomiasis caused by Trypanosoma brucei gambiense. We hypothesise, therefore, the skin represents an anatomic reservoir of infection. Here we definitively show that substantial quantities of trypanosomes exist within the skin following experimental infection, which can be transmitted to the tsetse vector, even in the absence of detectable parasitaemia. Importantly, we demonstrate the presence of extravascular parasites in human skin biopsies from undiagnosed individuals. The identification of this novel reservoir requires a re-evaluation of current diagnostic methods and control policies. More broadly, our results indicate that transmission is a key evolutionary force driving parasite extravasation that could further result in tissue invasion-dependent pathology. DOI:http://dx.doi.org/10.7554/eLife.17716.001
Collapse
Affiliation(s)
- Paul Capewell
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom.,College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Henry Wellcome Building for Comparative Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Christelle Cren-Travaillé
- Trypanosome Transmission Group, Trypanosome Cell Biology Unit, INSERM U1201, Paris, France.,Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Francesco Marchesi
- Veterinary Diagnostic Services, Veterinary School, University of Glasgow, Glasgow, United Kingdom
| | - Pamela Johnston
- Veterinary Diagnostic Services, Veterinary School, University of Glasgow, Glasgow, United Kingdom
| | - Caroline Clucas
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom.,College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Henry Wellcome Building for Comparative Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Robert A Benson
- College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Institute of Infection, Immunology and Inflammation, University of Glasgow, Glasgow, United Kingdom.,Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Taylor-Anne Gorman
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom.,College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Henry Wellcome Building for Comparative Medical Sciences, University of Glasgow, Glasgow, United Kingdom.,Institute of Infection, Immunology and Inflammation, University of Glasgow, Glasgow, United Kingdom.,Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Estefania Calvo-Alvarez
- Trypanosome Transmission Group, Trypanosome Cell Biology Unit, INSERM U1201, Paris, France.,Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Aline Crouzols
- Trypanosome Transmission Group, Trypanosome Cell Biology Unit, INSERM U1201, Paris, France.,Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Grégory Jouvion
- Human Histopathology and Animal Models Unit, Institut Pasteur, Paris, France
| | - Vincent Jamonneau
- Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Campus International de Baillarguet, Montpellier, France
| | - William Weir
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom.,College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Henry Wellcome Building for Comparative Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - M Lynn Stevenson
- Veterinary Diagnostic Services, Veterinary School, University of Glasgow, Glasgow, United Kingdom
| | - Kerry O'Neill
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom.,College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Henry Wellcome Building for Comparative Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Anneli Cooper
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom.,College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Henry Wellcome Building for Comparative Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| | | | - Bruno Bucheton
- Institut de Recherche pour le Développement, Unité Mixte de Recherche IRD-CIRAD 177, Campus International de Baillarguet, Montpellier, France
| | - Dieudonné Mumba Ngoyi
- Department of Parasitology, National Institute of Biomedical Research, Kinshasa, Democratic Republic of the Congo
| | - Paul Garside
- College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Institute of Infection, Immunology and Inflammation, University of Glasgow, Glasgow, United Kingdom.,Glasgow Biomedical Research Centre, University of Glasgow, Glasgow, United Kingdom
| | - Brice Rotureau
- Trypanosome Transmission Group, Trypanosome Cell Biology Unit, INSERM U1201, Paris, France.,Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Annette MacLeod
- Wellcome Trust Centre for Molecular Parasitology, University of Glasgow, Glasgow, United Kingdom.,College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.,Henry Wellcome Building for Comparative Medical Sciences, University of Glasgow, Glasgow, United Kingdom
| |
Collapse
|
33
|
Sending a message: extracellular vesicles of pathogenic protozoan parasites. Nat Rev Microbiol 2016; 14:669-675. [DOI: 10.1038/nrmicro.2016.110] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
34
|
Gineau L, Courtin D, Camara M, Ilboudo H, Jamonneau V, Dias FC, Tokplonou L, Milet J, Mendonça PB, Castelli EC, Camara O, Camara M, Favier B, Rouas-Freiss N, Moreau P, Donadi EA, Bucheton B, Sabbagh A, Garcia A. Human Leukocyte Antigen-G: A Promising Prognostic Marker of Disease Progression to Improve the Control of Human African Trypanosomiasis. Clin Infect Dis 2016; 63:1189-1197. [PMID: 27470243 DOI: 10.1093/cid/ciw505] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 07/21/2016] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Human African trypanosomiasis (HAT) caused by Trypanosoma brucei gambiense can be diagnosed in the early hemolymphatic stage (stage 1 [S1]) or meningoencephalitic stage (stage 2 [S2]). Importantly, individuals harbouring high and specific antibody responses to Tbg antigens but negative parasitology are also diagnosed in the field (seropositive [SERO]). Whereas some develop the disease in the months following their initial diagnosis (SERO/HAT), others remain parasitologically negative for long periods (SERO) and are apparently able to control infection. Human leucocyte antigen (HLA)-G, an immunosuppressive molecule, could play a critical role in this variability of progression between infection and disease. METHODS Soluble HLA-G (sHLA-G) was measured in plasma for patients in the SERO (n = 65), SERO/HAT (n = 14), or HAT (n = 268) group and in cerebrospinal fluid for patients in S1 (n = 55), early S2 (n = 93), or late S2 (n = 110). Associations between these different statuses and the soluble level or genetic polymorphisms of HLA-G were explored. RESULTS Plasma sHLA-G levels were significantly higher in HAT (P = 6 × 10-7) and SERO/HAT (P = .007) than SERO patients. No difference was observed between the SERO/HAT and HAT groups. Within the HAT group, specific haplotypes (HG010102 and HG0103) displayed increased frequencies in S1 (P = .013) and late S2 (P = .036), respectively. CONCLUSIONS These results strongly suggest the involvement of HLA-G in HAT disease progression. Importantly, high plasma sHLA-G levels in SERO patients could be predictive of subsequent disease development and could represent a serological marker to help guide therapeutic decision making. Further studies are necessary to assess the predictive nature of HLA-G and to estimate both sensitivity and specificity.
Collapse
Affiliation(s)
- Laure Gineau
- Institut de Recherche pour le Développement, UMR216 MERIT, Mère et Enfant face aux Infections Tropicales Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité
| | - David Courtin
- Institut de Recherche pour le Développement, UMR216 MERIT, Mère et Enfant face aux Infections Tropicales Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité
| | - Mamadou Camara
- Ministère de la Santé et de l'Hygiène Publique, Programme National de Lutte contre la Trypanosomose Humaine Africaine, Conakry, Guinea
| | - Hamidou Ilboudo
- Centre International de Recherche-Développement sur l'Elevage en Zones Subhumides, Unité de Recherches sur les Bases Biologiques de la Lutte Intégrée, Bobo-Dioulasso, Burkina Faso
| | - Vincent Jamonneau
- Centre International de Recherche-Développement sur l'Elevage en Zones Subhumides, Unité de Recherches sur les Bases Biologiques de la Lutte Intégrée, Bobo-Dioulasso, Burkina Faso Institut de Recherche Pour le Développement, Campus International de Baillarguet, Montpellier, France
| | - Fabricio C Dias
- Division of Clinical Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto
| | - Leonidas Tokplonou
- Institut de Recherche Pour le Développement, UMR 216, Centre d'Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l'Enfance, Faculté des Sciences de la Santé, Cotonou, Bénin
| | - Jacqueline Milet
- Institut de Recherche pour le Développement, UMR216 MERIT, Mère et Enfant face aux Infections Tropicales Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité
| | - Priscila B Mendonça
- Division of Clinical Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto
| | - Erick C Castelli
- Department de Pathology, School of Medicine, UNESP-Universidade Estadual Paulista, Botucatu, São Paulo, Brazil
| | - Oumou Camara
- Ministère de la Santé et de l'Hygiène Publique, Programme National de Lutte contre la Trypanosomose Humaine Africaine, Conakry, Guinea
| | - Mariam Camara
- Ministère de la Santé et de l'Hygiène Publique, Programme National de Lutte contre la Trypanosomose Humaine Africaine, Conakry, Guinea
| | - Benoit Favier
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut des Maladies Emergentes et des Thérapies Innovantes, Service de Recherches en Hémato-Immunologie, Hôpital Saint-Louis Université Paris Diderot, Sorbonne Paris Cité, UMRE5, Institut Universitaire d'Hématologie, Hôpital Saint-Louis
| | - Nathalie Rouas-Freiss
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut des Maladies Emergentes et des Thérapies Innovantes, Service de Recherches en Hémato-Immunologie, Hôpital Saint-Louis Université Paris Diderot, Sorbonne Paris Cité, UMRE5, Institut Universitaire d'Hématologie, Hôpital Saint-Louis
| | - Philippe Moreau
- Commissariat à l'Energie Atomique et aux Energies Alternatives, Institut des Maladies Emergentes et des Thérapies Innovantes, Service de Recherches en Hémato-Immunologie, Hôpital Saint-Louis Université Paris Diderot, Sorbonne Paris Cité, UMRE5, Institut Universitaire d'Hématologie, Hôpital Saint-Louis
| | - Eduardo A Donadi
- Division of Clinical Immunology, School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto
| | - Bruno Bucheton
- Ministère de la Santé et de l'Hygiène Publique, Programme National de Lutte contre la Trypanosomose Humaine Africaine, Conakry, Guinea Institut de Recherche Pour le Développement, Campus International de Baillarguet, Montpellier, France
| | - Audrey Sabbagh
- Institut de Recherche pour le Développement, UMR216 MERIT, Mère et Enfant face aux Infections Tropicales Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité
| | - André Garcia
- Institut de Recherche pour le Développement, UMR216 MERIT, Mère et Enfant face aux Infections Tropicales Faculté de Pharmacie, Université Paris Descartes, Sorbonne Paris Cité Institut de Recherche Pour le Développement, UMR 216, Centre d'Etude et de Recherche sur le Paludisme Associé à la Grossesse et à l'Enfance, Faculté des Sciences de la Santé, Cotonou, Bénin
| |
Collapse
|
35
|
Caljon G, De Muylder G, Durnez L, Jennes W, Vanaerschot M, Dujardin JC. Alice in microbes' land: adaptations and counter-adaptations of vector-borne parasitic protozoa and their hosts. FEMS Microbiol Rev 2016; 40:664-85. [PMID: 27400870 DOI: 10.1093/femsre/fuw018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2016] [Indexed: 12/24/2022] Open
Abstract
In the present review, we aim to provide a general introduction to different facets of the arms race between pathogens and their hosts/environment, emphasizing its evolutionary aspects. We focus on vector-borne parasitic protozoa, which have to adapt to both invertebrate and vertebrate hosts. Using Leishmania, Trypanosoma and Plasmodium as main models, we review successively (i) the adaptations and counter-adaptations of parasites and their invertebrate host, (ii) the adaptations and counter-adaptations of parasites and their vertebrate host and (iii) the impact of human interventions (chemotherapy, vaccination, vector control and environmental changes) on these adaptations. We conclude by discussing the practical impact this knowledge can have on translational research and public health.
Collapse
Affiliation(s)
- Guy Caljon
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium University of Antwerp, Department of Biomedical Sciences, Laboratory of Microbiology, Parasitology and Health, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - Géraldine De Muylder
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Lies Durnez
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Wim Jennes
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Manu Vanaerschot
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium Columbia University, College of Physicians and Surgeons, Department of Microbiology and Immunology, Fidock Lab, New York, NY 10032, USA
| | - Jean-Claude Dujardin
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium University of Antwerp, Department of Biomedical Sciences, Laboratory of Microbiology, Parasitology and Health, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| |
Collapse
|
36
|
Yaro M, Munyard KA, Stear MJ, Groth DM. Combatting African Animal Trypanosomiasis (AAT) in livestock: The potential role of trypanotolerance. Vet Parasitol 2016; 225:43-52. [PMID: 27369574 DOI: 10.1016/j.vetpar.2016.05.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 04/29/2016] [Accepted: 05/01/2016] [Indexed: 01/09/2023]
Abstract
African Animal Trypanosomiasis (AAT) is endemic in at least 37 of the 54 countries in Africa. It is estimated to cause direct and indirect losses to the livestock production industry in excess of US$ 4.5 billion per annum. A century of intervention has yielded limited success, owing largely to the extraordinary complexity of the host-parasite interaction. Trypanotolerance, which refers to the inherent ability of some African livestock breeds, notably Djallonke sheep, N'Dama cattle and West African Dwarf goats, to withstand a trypanosomiasis challenge and still remain productive without any form of therapy, is an economically sustainable option for combatting this disease. Yet trypanotolerance has not been adequately exploited in the fight against AAT. In this review, we describe new insights into the genetic basis of trypanotolerance and discuss the potential of exploring this phenomenon as an integral part of the solution for AAT, particularly, in the context of African animal production systems.
Collapse
Affiliation(s)
- M Yaro
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia
| | - K A Munyard
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia
| | - M J Stear
- Institute of Biodiversity, Animal Health and Comparative Medicine, Glasgow University, Garscube Estate, Bearsden Road, Glasgow G61 1QH, UK
| | - D M Groth
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, GPO Box U1987, Perth, WA 6845, Australia.
| |
Collapse
|