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1.
Parasit Vectors ; 15(1): 224, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35733222

RESUMO

BACKGROUND: Tsetse flies can transmit various Trypanosoma spp. that cause trypanosomiasis in humans, wild animals, and domestic animals. Amplicon deep sequencing of the 12S ribosomal RNA (rRNA) gene can be used to detect mammalian tsetse hosts, and the 18S rRNA gene can be used to detect all associated eukaryotic pathogens, including Trypanosoma spp. METHODS: Tsetse flies were collected from the Serengeti National Park (n = 48), Maswa Game Reserve (n = 42), and Tarangire National Park (n = 49) in Tanzania in 2012-13. Amplicon deep sequencing targeting mammal-specific 12S rRNA and 18S rRNA genes was performed to screen the blood-feeding sources of tsetse flies and eukaryotic parasites in tsetse flies, respectively. RESULTS: 12S rRNA gene deep sequencing revealed that various mammals were blood-feeding sources of the tsetse flies, including humans, common warthogs, African buffalos, mice, giraffes, African elephants, waterbucks, and lions. Genes of humans were less frequently detected in Serengeti (P = 0.0024), whereas African buffaloes were detected more frequently as a blood-feeding source (P = 0.0010). 18S rRNA gene deep sequencing showed that six tsetse samples harbored the Trypanosoma gene, which was identified as Trypanosoma godfreyi and Trypanosoma simiae in subsequent ITS1 gene sequencing. CONCLUSIONS: Through amplicon deep sequencing targeting the 12S rRNA and 18S rRNA genes, various mammalian animals were identified as blood-meal sources, and two Trypanosoma species were detected in tsetse flies collected from the Maswa Game Reserve, Serengeti National Park, and Tarangire National Park in Tanzania. This study illustrates the patterns of parasitism of tsetse fly, wild animals targeted by the fly, and Trypanosoma spp. carried by the fly in Tanzania. It may provide essential data for formulating better strategies to control African trypanosomes.


Assuntos
Parasitos , Trypanosoma , Tripanossomíase Africana , Moscas Tsé-Tsé , Animais , Animais Selvagens/parasitologia , Insetos Vetores/parasitologia , Mamíferos/genética , Metagenômica , Camundongos , Parasitos/genética , RNA Ribossômico 18S/genética , Suínos , Tanzânia , Trypanosoma/genética , Moscas Tsé-Tsé/parasitologia
2.
Nat Commun ; 13(1): 3322, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680928

RESUMO

Trypanosomes causing African sleeping sickness use quorum-sensing (QS) to generate transmission-competent stumpy forms in mammalian hosts. This density-dependent process is signalled by oligopeptides that stimulate the signal transduction pathway leading to stumpy formation. Here, using mass spectrometry analysis, we identify peptidases released by trypanosomes and, for 12 peptidases, confirm their extracellular delivery. Thereafter, we determine the contribution of each peptidase to QS signal production using systematic inducible overexpression in vivo, and confirm this activity operates through the physiological QS signalling pathway. Gene knockout of the QS-active peptidases identifies two enzymes, oligopeptidase B and metallocarboxypeptidase 1, that significantly reduce QS when ablated individually. Further, combinatorial gene knockout of both peptidases confirms their dominance in the generation of the QS signal, with peptidase release of oligopeptidase B mediated via an unconventional protein secretion pathway. This work identifies how the QS signal driving trypanosome virulence and transmission is generated in mammalian hosts.


Assuntos
Trypanosoma brucei brucei , Trypanosoma , Tripanossomíase Africana , Animais , Mamíferos , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Percepção de Quorum/genética , Trypanosoma brucei brucei/metabolismo
3.
Genes (Basel) ; 13(6)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35741832

RESUMO

Parasites of medical importance, such as Leishmania and Trypanosoma, are characterized by the presence of thousands of circular DNA molecules forming a structure known as kinetoplast, within the mitochondria. The maxicircles, which are equivalent to the mitochondrial genome in other eukaryotes, have been proposed as a promising phylogenetic marker. Using whole-DNA sequencing data, it is also possible to assemble maxicircle sequences as shown here and in previous works. In this study, based on data available in public databases and using a bioinformatics workflow previously reported by our group, we assembled the complete coding region of the maxicircles for 26 prototypical strains of trypanosomatid species. Phylogenetic analysis based on this dataset resulted in a robust tree showing an accurate taxonomy of kinetoplastids, which was also able to discern between closely related Leishmania species that are usually difficult to discriminate by classical methodologies. In addition, we provide a dataset of the maxicircle sequences of 60 Leishmania infantum field isolates from America, Western Europe, North Africa, and Eastern Europe. In agreement with previous studies, our data indicate that L. infantum parasites from Brazil are highly homogeneous and closely related to European strains, which were transferred there during the discovery of America. However, this study showed the existence of different L. infantum populations/clades within the Mediterranean region. A maxicircle signature for each clade has been established. Interestingly, two L. infantum clades were found coexisting in the same region of Spain, one similar to the American strains, represented by the Spanish JPCM5 reference strain, and the other, named "non-JPC like", may be related to an important leishmaniasis outbreak that occurred in Madrid a few years ago. In conclusion, the maxicircle sequence emerges as a robust molecular marker for phylogenetic analysis and species typing within the kinetoplastids, which also has the potential to discriminate intraspecific variability.


Assuntos
Genoma Mitocondrial , Leishmania infantum , Leishmaniose , Trypanosoma , Humanos , Leishmania infantum/genética , Filogenia
4.
Vet Parasitol Reg Stud Reports ; 32: 100741, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35725104

RESUMO

Camels are the most adapted species to the harsh ecosystems of the African continent where they represent 80% of world's population. However, they can be susceptible to many pathogens such as Trypanosoma evansi. This parasite is widely distributed in Africa and represents a real threat to animal health and production. In Tunisia, despite its importance, this disease is underestimated and only a few data are available. The present study aims to investigate the prevalence of the disease by combining microscopic and serological tests. A cross-sectional study was conducted on 307 dromedary camels randomly selected from Southern Tunisia. Collected blood samples were microscopically examined and tested with Card Agglutination Trypanosomiasis Test to detect anti-T. evansi antibodies. The microscopic and serological prevalence were estimated at 2.93 and 62.54%, respectively. Microscopic examination showed morphological features of T. evansi. All positives samples were collected from aged males (>5 years old). Seroprevalence was similar for both sexes but it was higher in dry season and in the southwest of Tunisia. The present study revealed high prevalence of T. evansi infection among dromedary camels. This highlights the need for adequate control measures based on the detection and treatment of infected animals and vector control. We recommend investigating the prevalence of infection in other domestic animals living in the same environment.


Assuntos
Camelus , Trypanosoma , Animais , Camelus/parasitologia , Estudos Transversais , Ecossistema , Feminino , Masculino , Estudos Soroepidemiológicos
5.
Vet Parasitol ; 306: 109723, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35643575

RESUMO

Trypanosoma (T.) vivax is one of the animal trypanosomes species causing calf mortality and economic losses in Togo. Despite its importance as the most widely distributed trypanosome species, T. vivax has received little attention because it is difficult to cultivate most field isolates in rodents. No molecular diagnostic tools for the identification of drug-resistant in T. vivax are currently available. Herein, four field isolates of T. vivax from Togo were cryopreserved and assessed for susceptibility to diminazene aceturate (DA) and isometamidium chloride (ISM) in goats. For field isolate preparation, 1 ml of blood from an infected goat was diluted in 111 µl of phosphate-buffered-saline and stored in liquid nitrogen. The in vivo experiment drug test was performed using twenty Sahelian goats with six-month of age and weighing 14.5 ± 1.6 kg. These experimental goats were purchased from a tsetse free-area Dori, a Sahelian region of Burkina Faso. The cryopreserved T. vivax isolates with unknowns, DA, and ISM sensitivity was inoculated to five goats and one goat was used as control. Each animal was inoculated by intravenously route 1 × 105 trypanosomes from the donor goat. Relapses were earlier in the first phase of treatment (14.85 ± 1.08 days) compared with the second phase (20 ± 3.39 days). The overall mean PCV of the control group decreased from 32% to 17% at day-60 (P-value < 0.001). Three isolates were phenotypically resistant to 0.5 mg per kg body weight (BW) ISM and one for 3.5 mg per kg BW of DA. There were no relapses with the 7 mg per kg BW dose DA. This study shows the resistance of T. vivax to two main trypanocidal drugs in different villages of Mango. The results suggest the extension of surveillance strategies to remote villages in Togo and will guide the veterinarian or herder in choosing a mass treatment strategy. Further studies will be needed to better understand the molecular basis of the observed resistance.


Assuntos
Doenças das Cabras , Tripanossomicidas , Trypanosoma , Tripanossomíase Africana , Animais , Doenças das Cabras/tratamento farmacológico , Cabras , Togo/epidemiologia , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico , Trypanosoma vivax , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/veterinária
6.
Nat Commun ; 13(1): 3084, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35654893

RESUMO

Mitochondrial protein import in the parasitic protozoan Trypanosoma brucei is mediated by the atypical outer membrane translocase, ATOM. It consists of seven subunits including ATOM69, the import receptor for hydrophobic proteins. Ablation of ATOM69, but not of any other subunit, triggers a unique quality control pathway resulting in the proteasomal degradation of non-imported mitochondrial proteins. The process requires a protein of unknown function, an E3 ubiquitin ligase and the ubiquitin-like protein (TbUbL1), which all are recruited to the mitochondrion upon ATOM69 depletion. TbUbL1 is a nuclear protein, a fraction of which is released to the cytosol upon triggering of the pathway. Nuclear release is essential as cytosolic TbUbL1 can bind mislocalised mitochondrial proteins and likely transfers them to the proteasome. Mitochondrial quality control has previously been studied in yeast and metazoans. Finding such a pathway in the highly diverged trypanosomes suggests such pathways are an obligate feature of all eukaryotes.


Assuntos
Trypanosoma brucei brucei , Trypanosoma , Proteínas de Transporte/metabolismo , Núcleo Celular/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Saccharomyces cerevisiae/metabolismo , Trypanosoma brucei brucei/metabolismo
7.
Nucleic Acids Res ; 50(10): 5818-5833, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35580050

RESUMO

The assembly of high molecular mass ribonucleoprotein complexes typically relies on the binary interaction of defined RNA sequences or precisely folded RNA motifs with dedicated RNA-binding domains on the protein side. Here we describe a new molecular recognition principle of RNA molecules by a high molecular mass protein complex. By chemically probing the solvent accessibility of mitochondrial pre-mRNAs when bound to the Trypanosoma brucei editosome, we identified multiple similar but non-identical RNA motifs as editosome contact sites. However, by treating the different motifs as mathematical graph objects we demonstrate that they fit a consensus 2D-graph consisting of 4 vertices (V) and 3 edges (E) with a Laplacian eigenvalue of 0.5477 (λ2). We establish that synthetic 4V(3E)-RNAs are sufficient to compete for the editosomal pre-mRNA binding site and that they inhibit RNA editing in vitro. Furthermore, we demonstrate that only two topological indices are necessary to predict the binding of any RNA motif to the editosome with a high level of confidence. Our analysis corroborates that the editosome has adapted to the structural multiplicity of the mitochondrial mRNA folding space by recognizing a fuzzy continuum of RNA folds that fit a consensus graph descriptor.


Assuntos
Edição de RNA , Trypanosoma/genética , Proteínas de Protozoários/metabolismo , RNA/genética , RNA/metabolismo , RNA de Protozoário/genética , RNA de Protozoário/metabolismo
8.
J Cell Physiol ; 237(6): 2654-2667, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35616248

RESUMO

African trypanosomes are early branching protists that cause human and animal diseases, termed trypanosomiases. They have been under intensive study for more than 100 years and have contributed significantly to our understanding of eukaryotic biology. The combination of conserved and parasite-specific features mean that their flagellum has gained particular attention. Here, we discuss the different structural features of the flagellum and their role in transmission and virulence. We highlight the possibilities of targeting flagellar function to cure trypanosome infections and help in the fight to eliminate trypanosomiases.


Assuntos
Trypanosoma , Tripanossomíase Africana , Tripanossomíase , Animais , Flagelos , Tripanossomíase Africana/tratamento farmacológico , Virulência
9.
Sci Rep ; 12(1): 8611, 2022 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-35597818

RESUMO

Bees are important pollinators in wild and agricultural ecosystems, and understanding the factors driving their global declines is key to maintaining these pollination services. Learning, which has been a focus of previous ecotoxicological studies in bees, may play a key role in driving colony fitness. Here we move beyond the standard single-stressor approach to ask how multiple stressors, an agrochemical (sulfoxaflor, a relatively new insecticide) and a parasite (Crithidia bombi, a prevalent gut parasite of bumblebees), impact learning in the bumblebee Bombus terrestris. We developed a modified version of the classic proboscis extension reflex assay to assess the combined effects of acute oral sulfoxaflor exposure and infection by C. bombi on olfactory learning of bumblebee workers. We found no evidence that either sulfoxaflor, C. bombi, or their combination had any significant effect on bumblebee olfactory learning, despite their known negative impacts on other aspects of bumblebee health. This suggests that losses in cognitive ability, as measured here, are unlikely to explain the impacts of sulfoxaflor and its interactions with other stressors on bumblebees. Our novel methodology provides a model system within which to test interactive effects of other key stressors on bee health.


Assuntos
Parasitos , Trypanosoma , Animais , Abelhas , Crithidia , Ecossistema , Piridinas , Compostos de Enxofre
10.
Vet Parasitol Reg Stud Reports ; 31: 100728, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35569913

RESUMO

Trypanosoma evansi, a unicellular haemoflagellate, causes surra in bovines and other economically important livestock species. We report here the epidemiological variables associated with the high prevalence of T. evansi infection in cattle in the plain agro-climatic zone of Chhattisgarh state, India. A total of 920 blood and sera samples were tested by a combination of parasitological, molecular and serodiagnostic tests. An overall prevalence of T. evansi was recorded as 4.57% (95% CI: 3.22-5.92%), 6.09% (95% CI: 4.54-7.63%), 63.91% (95% CI: 60.81-67.01%) and 55.33% (95% CI: 52.12-58.54%) by direct microscopy, PCR, ELISA and IFAT, respectively. The Chi-Square test established a significant correlation between the prevalence of T. evansi and the season, breed and place of the study, while the association with the gender and age of the animals was insignificant. The analysis of the prevalence ratio revealed a significant association of the breed, season and place of study with the prevalence of T. evansi. As per PR observed, the prevalence was 1.63 times higher in summer and 1.68 times higher in the rainy season than in the winter (reference season). The prevalence was higher in all the districts as compared to Rajnandgaon (reference district). The prevalence ratio in Sahiwal and HF cross-breed cattle was significantly higher than the Gir breed of cattle (reference). Durg district recorded the highest prevalence of surra, and the difference was significant. The medium IFAT titre, determined in a large number of sera collected from Durg, predicted a higher incidence of trypanosomosis in that district. Since T. evansi has a broad host range, the study predicted that a large population of livestock in Chhattisgarh state were at high risk of T. evansi infection. Treatment of the subclinically and clinically infected animals with selective curative drugs, such as diminazene aceturate, isometamidium chloride or the combination of quinapyramine sulphate and quinapyramine chloride, could help restore productivity and help in containing the infection.


Assuntos
Doenças dos Bovinos , Trypanosoma , Tripanossomíase , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Diminazena , Gado , Prevalência , Tripanossomíase/epidemiologia , Tripanossomíase/veterinária
11.
Sci Rep ; 12(1): 8933, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35624132

RESUMO

Surra is a non-cyclic parasitic disease caused by Trypanosoma evansi (T. evansi) and spread by biting flies. The disease has a severe impact on camel health, productivity, and market value, posing a significant threat to food safety and the economy. In a cross-sectional study, 370 blood samples were collected from camels in three Egyptian governorates. Samples were tested using parasitological (thin blood smear (TBS)), card agglutination test for T. evansi (CATT), and PCR to estimate the prevalence of T. evansi infection. Overall, the prevalence of T. evansi among examined camels was 17.3%, 18.9% and 22.7% using TBS, CATT and PCR methods, respectively. The risk of T. evansi infection in older camels (> 10 years) is higher than that in young ones (odds ratio (OR) = 9; 95% CI: 3.5-23.1), particularly during spring (OR = 2.5; 95% CI: 1.1-5.7). Furthermore, females and poor conditioned camels were 2.6 and four times more likely to get infection than males and good conditioned camels, respectively. The level of agreement between diagnostics tests were perfect kappa (> 0.83). Moreover, CATT showed higher sensitivity (0.83; 95% CI: 0.74-0.91) than TBS (0.76; 95% CI: 0.66-0.85) and both had perfect specificity (100%). In conclusion, our findings revealed a high rate of T. evansi infection in camels from the three Egyptian governorates. The CATT is a good test for routine use in control program of trypanosomiasis in camels.


Assuntos
Trypanosoma , Tripanossomíase , Animais , Camelus/parasitologia , Estudos Transversais , Feminino , Masculino , Prevalência , Fatores de Risco , Tripanossomíase/epidemiologia , Tripanossomíase/veterinária
12.
Front Immunol ; 13: 852091, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634275

RESUMO

The protozoan parasite Trypanosoma evansi is responsible for causing surra in a variety of mammalian hosts and is spread by many vectors over a wide geographical area making it an ideal target for irradiation as a tool to study the initial events that occur during infection. Parasites irradiated at the representative doses 100Gy, 140Gy, and 200Gy were used to inoculate BALB/c mice revealing that parasites irradiated at 200Gy were unable to establish disease in all mice. Cytokine analysis of mice inoculated with 200Gy of irradiated parasites showed significantly lower levels of interleukins when compared to mice inoculated with non-irradiated and 100Gy irradiated parasites. Irradiation also differentially affected the abundance of gene transcripts in a dose-dependent trend measured at 6- and 20-hours post-irradiation with 234, 325, and 484 gene transcripts affected 6 hours post-irradiation for 100Gy-, 140Gy- and 200Gy-irradiated parasites, respectively. At 20 hours post-irradiation, 422, 381, and 457 gene transcripts were affected by irradiation at 100Gy, 140Gy, and 200Gy, respectively. A gene ontology (GO) term analysis was carried out for the three representative doses at 6 hours and 20 hours post-irradiation revealing different processes occurring at 20 hours when compared to 6 hours for 100Gy irradiation. The top ten most significant processes had a negative Z score. These processes fall in significance at 140Gy and even further at 200Gy, revealing that they were least likely to occur at 200Gy, and thus may have been responsible for infection in mice by 100Gy and 140Gy irradiated parasites. When looking at 100Gy irradiated parasites 20 hours post-irradiation processes with a positive Z score, we identified genes that were involved in multiple processes and compared their fold change values at 6 hours and 20 hours. We present these genes as possibly necessary for repair from irradiation damage at 6 hours and suggestive of being involved in the establishment of disease in mice at 20 hours post-irradiation. A potential strategy using this information to develop a whole parasite vaccine is also postulated.


Assuntos
Parasitos , Trypanosoma , Animais , Raios gama/efeitos adversos , Mamíferos , Camundongos , Camundongos Endogâmicos BALB C , Trypanosoma/genética
13.
Vet Parasitol ; 306: 109716, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35618508

RESUMO

Surra is caused by Trypanosoma evansi, a flagellated parasite that affects domestic and wild animals. Surra is a neglected tropical disease causing serious problems to camels breed in Algeria. The aim of our study consists to extract the major risk factors that predict T.evansi infection in dromedaries using artificial neural networks. This investigation was conducted on 115 dromedaries from Ghardaïa district, Southern Algeria. The immune trypanolysis test was used to detect antibodies against T. evansi. Firstly, the gamma test has been used to choose optimal input parameters. The obtained results indicate that the age, gender, breed, clinical manifestations history, herd size, as well as the animal activities were the most predictors of T. evansi infection. Afterward, an artificial neural network method has been performed for modelling the proposed optimal inputs and their accuracy was assessed through seven statistical indicators. The comparative study indicates the effectiveness of the (6-9-1) model trained by the Tansig transfer function. The proposed model has demonstrated a good performance: 0.925 for training data and 0.962 for validation data. Furthermore it could be very useful for the rapid intervention of veterinarians as close as possible to the point-of-care (POC).


Assuntos
Trypanosoma , Tripanossomíase , Animais , Anticorpos Antiprotozoários , Camelus/parasitologia , Redes Neurais de Computação , Tripanossomíase/diagnóstico , Tripanossomíase/epidemiologia , Tripanossomíase/veterinária
14.
Front Immunol ; 13: 865395, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464430

RESUMO

African trypanosomes are extracellular flagellated unicellular protozoan parasites transmitted by tsetse flies and causing Sleeping Sickness disease in humans and Nagana disease in cattle and other livestock. These diseases are usually characterized by the development of a fatal chronic inflammatory disease if left untreated. During African trypanosome infection and many other infectious diseases, the immune response is mediating a see-saw balance between effective/protective immunity and excessive infection-induced inflammation that can cause collateral tissue damage. African trypanosomes are known to trigger a strong type I pro-inflammatory response, which contributes to peak parasitaemia control, but this can culminate into the development of immunopathologies, such as anaemia and liver injury, if not tightly controlled. In this context, the macrophage migration inhibitory factor (MIF) and the interleukin-10 (IL-10) cytokines may operate as a molecular "Yin-Yang" in the modulation of the host immune microenvironment during African trypanosome infection, and possibly other infectious diseases. MIF is a pleiotropic pro-inflammatory cytokine and critical upstream mediator of immune and inflammatory responses, associated with exaggerated inflammation and immunopathology. For example, it plays a crucial role in the pro-inflammatory response against African trypanosomes and other pathogens, thereby promoting the development of immunopathologies. On the other hand, IL-10 is an anti-inflammatory cytokine, acting as a master regulator of inflammation during both African trypanosomiasis and other diseases. IL-10 is crucial to counteract the strong MIF-induced pro-inflammatory response, leading to pathology control. Hence, novel strategies capable of blocking MIF and/or promoting IL-10 receptor signaling pathways, could potentially be used as therapy to counteract immunopathology development during African trypanosome infection, as well as during other infectious conditions. Together, this review aims at summarizing the current knowledge on the opposite immunopathological molecular "Yin-Yang" switch roles of MIF and IL-10 in the modulation of the host immune microenvironment during infection, and more particularly during African trypanosomiasis as a paradigm.


Assuntos
Doenças Transmissíveis , Fatores Inibidores da Migração de Macrófagos , Trypanosoma , Tripanossomíase Africana , Animais , Bovinos , Interleucina-10 , Parasitemia , Yin-Yang
15.
PLoS Negl Trop Dis ; 16(4): e0010300, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35442960

RESUMO

BACKGROUND: Animal African Trypanosomiasis (AAT) is one of the most economically important diseases affecting livestock productivity in sub-Saharan Africa. The disease is caused by a broad range of Trypanosoma spp., infecting both wild and domesticated animals through cyclical and mechanical transmission. This study aimed to characterize trypanosomes present in cattle at regular intervals over two years in an AAT endemic and a non-endemic region of Ghana. METHODOLOGY/PRINCIPAL FINDINGS: Groups of cattle at Accra and Adidome were selected based on their geographical location, tsetse fly density, prevalence of trypanosomiasis and the breed of cattle available. Blood for DNA extraction was collected at approximately four to five-week intervals over a two-year period. Trypanosome DNA were detected by a sensitive nested PCR targeting the tubulin gene array and massively parallel sequencing of barcoded amplicons. Analysis of the data was a semi-quantitative estimation of infection levels using read counts obtained from the sequencing as a proxy for infection levels. Majority of the cattle were infected with multiple species most of the time [190/259 (73%) at Adidome and 191/324 (59%) at Accra], with T. vivax being the most abundant. The level of infection and in particular T. vivax, was higher in Adidome, the location with a high density of tsetse flies. The infection level varied over the time course, the timings of this variation were not consistent and in Adidome it appeared to be independent of prophylactic treatment for trypanosome infection. Effect of gender or breed on infection levels was insignificant. CONCLUSIONS/SIGNIFICANCE: Most cattle were infected with low levels of several trypanosome species at both study sites, with T. vivax being the most abundant. The measurements of infection over time provided insight to the importance of the approach in identifying cattle that could suppress trypanosome infection over an extended time and may serve as reservoir.


Assuntos
Trypanosoma , Tripanossomíase Africana , Moscas Tsé-Tsé , Animais , Bovinos , Gana/epidemiologia , Sequenciamento de Nucleotídeos em Larga Escala , Prevalência , Trypanosoma/genética , Tripanossomíase Africana/epidemiologia , Tripanossomíase Africana/veterinária , Moscas Tsé-Tsé/genética
16.
Parasitol Res ; 121(6): 1719-1724, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35435514

RESUMO

Parasitism is a dynamic ecological phenomenon that is constantly influenced by the environment and intrinsic factors of the host. We aimed to evaluate the influence of vegetation, environmental temperature, reproductive conditions, sex, and body condition (BC) on the detection of Trypanosoma spp. in the blood of Thrichomys fosteri in the Pantanal region, an enzootic area for trypanosomiasis. Whole blood was collected from the tip of the tail, and nPCR was performed for Trypanosoma spp. detection from the DNA extracted from the resultant blood clot. Statistical analyses were performed using generalized linear models. Our results showed that there is a greater probability of detection of Trypanosoma spp. in the bloodstream of animals with the highest BC values in periods with mild temperatures. Since T. fosteri is an abundant and common prey for carnivores, even in periods with low temperatures and consequent decrease in the reproduction and activities of the blood-sucking arthropod vectors, the maintenance of Trypanosoma spp. in the studied area would be guaranteed via predation (trophic network) of T. fosteri individuals with good BC and patent parasitemia. Furthermore, T. fosteri, which displays Trypanosoma spp. in the bloodstream, would be reproducing adequately because we found no influence between the reproductive condition and the detection of Trypanosoma spp. in T. fosteri. The caviomorph rodent T. fostei is an important species for the maintenance of Trypanosoma spp. in the Pantanal biome.


Assuntos
Trypanosoma , Tripanossomíase , Animais , Brasil , Ecossistema , Parasitemia , Roedores , Trypanosoma/genética , Tripanossomíase/veterinária
17.
Mol Biochem Parasitol ; 249: 111476, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35378143

RESUMO

Proteins of interest are frequently expressed with a fusion-tag to facilitate experimental analysis. In trypanosomatids, which are typically diploid, a tag-encoding DNA fragment is typically fused to one native allele. However, since recombinant cells represent ≪0.1% of the population following transfection, these DNA fragments also incorporate a marker cassette for positive selection. Consequently, native mRNA untranslated regions (UTRs) are replaced, potentially perturbing gene expression; in trypanosomatids, UTRs often impact gene expression in the context of widespread and constitutive polycistronic transcription. We sought to develop a tagging strategy that preserves native UTRs in bloodstream-form African trypanosomes, and here we describe a CRISPR/Cas9-based knock-in approach to drive precise and marker-free tagging of essential genes. Using simple tag-encoding amplicons, we tagged four proteins: a histone acetyltransferase, HAT2; a histone deacetylase, HDAC3; a cleavage and polyadenylation specificity factor, CPSF3; and a variant surface glycoprotein exclusion factor, VEX2. The approach maintained the native UTRs and yielded clonal strains expressing functional recombinant proteins, typically with both alleles tagged. We demonstrate utility for both immunofluorescence-based localisation and for enriching protein complexes; GFPHAT2 or GFPHDAC3 complexes in this case. This precision tagging approach facilitates the assembly of strains expressing essential recombinant genes with their native UTRs preserved.


Assuntos
Trypanosoma brucei brucei , Trypanosoma , Sistemas CRISPR-Cas , Genes Essenciais , Trypanosoma/genética , Trypanosoma brucei brucei/genética , Regiões não Traduzidas
20.
Biol Open ; 11(4)2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35373253

RESUMO

Trypanosoma theileri, a non-pathogenic parasite of bovines, has a predicted surface protein architecture that likely aids survival in its mammalian host. Their surface proteins are encoded by genes which account for ∼10% of their genome. A non-pathogenic parasite of sheep, Trypanosoma melophagium, is transmitted by the sheep ked and is closely related to T. theileri. To explore host and vector specificity between these species, we sequenced the T. melophagium genome and transcriptome and an annotated draft genome was assembled. T. melophagium was compared to 43 kinetoplastid genomes, including T. theileri. T. melophagium and T. theileri have an AT biased genome, the greatest bias of publicly available trypanosomatids. This trend may result from selection acting to decrease the genomic nucleotide cost. The T. melophagium genome is 6.3Mb smaller than T. theileri and large families of proteins, characteristic of the predicted surface of T. theileri, were found to be absent or greatly reduced in T. melophagium. Instead, T. melophagium has modestly expanded protein families associated with the avoidance of complement-mediated lysis. We propose that the contrasting genomic features of these species is linked to their mode of transmission from their insect vector to their mammalian host. This article has an associated First Person interview with the first author of the paper.


Assuntos
Dípteros , Trypanosoma , Animais , Bovinos , Dípteros/parasitologia , Genômica , Humanos , Insetos Vetores/parasitologia , Mamíferos , Filogenia , Ovinos , Trypanosoma/genética
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