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Wu D, Yang Y, Yang Y, Li L, Fu S, Wang L, Tan L, Lu X, Zhang W, Di W. An insulin-like signalling pathway model for Fasciola gigantica. BMC Vet Res 2024; 20:252. [PMID: 38851737 PMCID: PMC11162077 DOI: 10.1186/s12917-024-04107-7] [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: 02/07/2024] [Accepted: 05/31/2024] [Indexed: 06/10/2024] Open
Abstract
BACKGROUND The insulin/insulin-like signalling (IIS) pathway is common in mammals and invertebrates, and the IIS pathway is unknown in Fasciola gigantica. In the present study, the IIS pathway was reconstructed in F. gigantica. We defined the components involved in the IIS pathway and investigated the transcription profiles of these genes for all developmental stages of F. gigantica. In addition, the presence of these components in excretory and secretory products (ESPs) was predicted via signal peptide annotation. RESULTS The core components of the IIS pathway were detected in F. gigantica. Among these proteins, one ligand (FgILP) and one insulin-like molecule binding protein (FgIGFBP) were analysed. Interestingly, three receptors (FgIR-1/FgIR-2/FgIR-3) were detected, and a novel receptor, FgIR-3, was screened, suggesting novel functions. Fg14-3-3ζ, Fgirs, and Fgpp2a exhibited increased transcription in 42-day-old juveniles and 70-day-old juveniles, while Fgilp, Fgigfb, Fgsgk-1, Fgakt-1, Fgir-3, Fgpten, and Fgaap-1 exhibited increased transcription in metacercariae. FgILP, FgIGFBP, FgIR-2, FgIR-3, and two transcription factors (FgHSF-1 and FgSKN-1) were predicted to be present in FgESPs, indicating their exogenous roles. CONCLUSIONS This study helps to elucidate the signal transduction pathway of IIS in F. gigantica, which will aid in understanding the interaction between flukes and hosts, as well as in understanding fluke developmental regulation, and will also lay a foundation for further characterisation of the IIS pathways of trematodes.
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Affiliation(s)
- Dongqi Wu
- College of Animal Science and Technology, Guangxi University, Nanning, Guangxi, China
| | - Yuqing Yang
- College of Animal Science and Technology, Guangxi University, Nanning, Guangxi, China
| | - Yankun Yang
- College of Animal Science and Technology, Guangxi University, Nanning, Guangxi, China
| | - Liang Li
- College of Animal Science and Technology, Guangxi University, Nanning, Guangxi, China
| | - Shishi Fu
- College of Animal Science and Technology, Guangxi University, Nanning, Guangxi, China
| | - Lei Wang
- College of Animal Science and Technology, Guangxi University, Nanning, Guangxi, China
| | - Li Tan
- Wuhan Keqian Biology Limited Company, Wuhan, Hubei, China
| | - Xiuhong Lu
- Nanning Animal Disease Prevention and Control Center, Nanning, Guangxi, China
| | - Weiyu Zhang
- College of Animal Science and Technology, Guangxi University, Nanning, Guangxi, China
| | - Wenda Di
- College of Animal Science and Technology, Guangxi University, Nanning, Guangxi, China.
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Orrego MA, Szczesniak MW, Vasquez CM, Verastegui MR, Bustos JA, Garcia HH, Nash TE. Transcriptomic analysis of subarachnoid cysts of Taenia solium reveals mechanisms for uncontrolled proliferation and adaptations to the microenvironment. Sci Rep 2024; 14:11833. [PMID: 38782926 PMCID: PMC11116493 DOI: 10.1038/s41598-024-61973-9] [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: 02/01/2024] [Accepted: 05/13/2024] [Indexed: 05/25/2024] Open
Abstract
Subarachnoid neurocysticercosis (SANCC) is caused by an abnormally transformed form of the metacestode or larval form of the tapeworm Taenia solium. In contrast to vesicular parenchymal and ventricular located cysts that contain a viable scolex and are anlage of the adult tapeworm, the subarachnoid cyst proliferates to form aberrant membranous cystic masses within the subarachnoid spaces that cause mass effects and acute and chronic arachnoiditis. How subarachnoid cyst proliferates and interacts with the human host is poorly understood, but parasite stem cells (germinative cells) likely participate. RNA-seq analysis of the subarachnoid cyst bladder wall compared to the bladder wall and scolex of the vesicular cyst revealed that the subarachnoid form exhibits activation of signaling pathways that promote proliferation and increased lipid metabolism. These adaptions allow growth in a nutrient-limited cerebral spinal fluid. In addition, we identified therapeutic drug targets that would inhibit growth of the parasite, potentially increase effectiveness of treatment, and shorten its duration.
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Affiliation(s)
- Miguel A Orrego
- Laboratory of Immunopathology in Neurocysticercosis, Facultad de Ciencias e Ingenierías, Universidad Peruana Cayetano Heredia, Lima, Peru.
- Center for Global Health, Universidad Peruana Cayetano Heredia, Lima, Peru.
| | - Michal W Szczesniak
- Institute of Human Biology and Evolution, Adam Mickiewicz University in Poznan, Poznan, Poland
| | - Carlos M Vasquez
- Department of Neurosurgery, Instituto Nacional de Ciencias Neurológicas, Lima, Peru
| | - Manuela R Verastegui
- Infectious Diseases Research Laboratory, Facultad de Ciencias e Ingenierías, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Javier A Bustos
- Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima, Peru
- Center for Global Health, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Hector H Garcia
- Laboratory of Immunopathology in Neurocysticercosis, Facultad de Ciencias e Ingenierías, Universidad Peruana Cayetano Heredia, Lima, Peru
- Cysticercosis Unit, Instituto Nacional de Ciencias Neurológicas, Lima, Peru
- Center for Global Health, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Theodore E Nash
- Laboratory of Immunopathology in Neurocysticercosis, Facultad de Ciencias e Ingenierías, Universidad Peruana Cayetano Heredia, Lima, Peru
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Derakhshani A, Mousavi SM, Rezaei M, Afgar A, Keyhani AR, Mohammadi MA, Dabiri S, Fasihi Harandi M. Natural history of Echinococcus granulosus microcyst development in long term in vitro culture and molecular and morphological changes induced by insulin and BMP-4. Front Vet Sci 2023; 9:1068602. [PMID: 36699324 PMCID: PMC9868913 DOI: 10.3389/fvets.2022.1068602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023] Open
Abstract
Introduction Cystic echinococcosis (CE) caused by the cestode Echinococcus granulosus is a disease of worldwide public health and economic importance. The determinants and underlying cellular mechanisms of CE development and fate in intermediate hosts are largely unknown. Hormones and cytokines such as insulin and BMP-4 are the key players in the development, differentiation, and apoptosis. In this study, we evaluated the long term natural history of E. granulosus microcysts in an vitro setting and the molecular and morphological changes induced by the growth factors, insulin and BMP4 during the development of metacestode stage of E. granulosus. Methods E. granulosus protoscoleces were cultivated and the parasite development was followed in the long term mono-phasic culture for 105 days and the morphometric, molecular and immunohistochemical changes were evaluated, including the microcysts number and size, microcysts development and deformation rates as well as the markers of calcification (Alizarin Red staining) and apoptosis (BAX, BCL2, Caspase-3, Caspase-8 and TNF-α expression) in the microcysts. Also the biological, histological and molecular consequences of insulin and BMP-4 treatment on the parasite development were evaluated. Results Insulin and BMP-4 treatment of microcysts resulted in significant increase in microcyst formation, increased size, reduced apoptosis and deformation of the microcysts. Alizarin red staining of the microcysts treated with the insulin and BMP-4 confirmed that calcium deposition is significantly lower than the untreated microcysts. Also Alizarin Red staining and Immunohistochemistry of the microcysts indicates that calcium accumulation in deformed microcysts is higher than the normal ones on day 105. The microcysts began to wrinkle and the germinal layer was partially detached from the laminated layer on day 84. Conclusion Results of the present study suggest that the degenerative changes in hydatid cysts can be slowed down by insulin and BMP-4, indicating that cellular factors and host hormones could contribute to the longevity of hydatid cysts. Significant evidences are provided suggesting that the microcysts cultivated in vitro can undergo calcification and apoptotic processes similar to what have been observed in the natural hydatid infection in the intermediate hosts.
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Affiliation(s)
- Ali Derakhshani
- Research Center for Hydatid Disease in Iran, Kerman University of Medical Sciences, Kerman, Iran
| | - Seyed Mohammad Mousavi
- Research Center for Hydatid Disease in Iran, Kerman University of Medical Sciences, Kerman, Iran
| | - Masoud Rezaei
- Research Center for Hydatid Disease in Iran, Kerman University of Medical Sciences, Kerman, Iran
| | - Ali Afgar
- Research Center for Hydatid Disease in Iran, Kerman University of Medical Sciences, Kerman, Iran,Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran
| | - Ali Reza Keyhani
- Leishmaniasis Research Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Ali Mohammadi
- Research Center for Hydatid Disease in Iran, Kerman University of Medical Sciences, Kerman, Iran
| | - Shahriar Dabiri
- Department of Pathology, Afzalipour Medical School, Pathology and Stem Cells Research Center, Kerman University of Medical Sciences, Kerman, Iran
| | - Majid Fasihi Harandi
- Research Center for Hydatid Disease in Iran, Kerman University of Medical Sciences, Kerman, Iran,*Correspondence: Majid Fasihi Harandi ✉
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Feng C, Cheng Z, Xu Z, Tian Y, Tian H, Liu F, Luo D, Wang Y. EmCyclinD-EmCDK4/6 complex is involved in the host EGF-mediated proliferation of Echinococcus multilocularis germinative cells via the EGFR-ERK pathway. Front Microbiol 2022; 13:968872. [PMID: 36033888 PMCID: PMC9410764 DOI: 10.3389/fmicb.2022.968872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 07/11/2022] [Indexed: 11/13/2022] Open
Abstract
The larval stage of the tapeworm Echinococcus multilocularis causes alveolar echinococcosis (AE), one of the most lethal helminthic infections in humans. The tumor-like growth and development of the metacestode larvae within host organs are driven by a population of somatic stem cells, the germinative cells, which represent the only proliferative cells in the parasite. Host-derived factors have been shown to promote germinative cell proliferation. Since cells sense the external signal mainly in G1 phase of the cell cycle, host factors are expected to exert impacts on the machinery regulating G1/S phase of the germinative cells, which still remains largely unknown in E. multilocularis. In this study, we described the characterization of two key members of the G1/S phase cell-cycle regulation, EmCyclinD and EmCDK4/6. Our data show that EmCyclinD and EmCDK4/6 display significant sequence similarity to their respective mammalian homologs, and that EmCyclinD interacts with EmCDK4/6, forming a kinase-active complex to activate its substrate Rb1. EmCyclinD was actively expressed in the germinative cells. Addition of human EGF caused an elevated expression of EmCyclinD while inhibition of the EGFR-ERK signaling pathway in the parasite reduced the expression of EmCyclinD and downstream transcriptional factors. Treatment with Palbociclib, a specific CDK4/6 inhibitor, downregulated the expression of cell cycle-related factors and impeded germinative cell proliferation and vesicle formation from protoscoleces. Our data demonstrated that the EmCyclinD-EmCDK4/6 complex participates in the cell cycle regulation of germinative cells which is mediated by host EGF via the EGFR-ERK-EmCyclinD pathway in E. multilocularis.
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Affiliation(s)
- Chonglv Feng
- State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Zhe Cheng
- State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Zhe Cheng,
| | - Zhijian Xu
- State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Ye Tian
- State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Huimin Tian
- Medical College, Xiamen University, Xiamen, Fujian, China
| | - Fan Liu
- Medical College, Xiamen University, Xiamen, Fujian, China
| | - Damin Luo
- State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Yanhai Wang
- State Key Laboratory of Cellular Stress Biology, Faculty of Medicine and Life Sciences, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- *Correspondence: Yanhai Wang,
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5
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Ustyantsev KV, Vavilova VY, Blinov AG, Berezikov EV. Macrostomum lignano as a model to study the genetics and genomics of parasitic flatworms. Vavilovskii Zhurnal Genet Selektsii 2021; 25:108-116. [PMID: 34901708 PMCID: PMC8629357 DOI: 10.18699/vj21.013] [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: 10/17/2020] [Revised: 12/03/2020] [Accepted: 12/08/2020] [Indexed: 12/02/2022] Open
Abstract
Hundreds of millions of people worldwide are infected by various species of parasitic flatworms. Without
treatment, acute and chronical infections frequently lead to the development of severe pathologies and even death.
Emerging data on a decreasing efficiency of some important anthelmintic compounds and the emergence of resistance to them force the search for alternative drugs. Parasitic flatworms have complex life cycles, are laborious and
expensive in culturing, and have a range of anatomic and physiological adaptations that complicate the application
of standard molecular-biological methods. On the other hand, free-living flatworm species, evolutionarily close to
parasitic flatworms, do not have the abovementioned difficulties, which makes them potential alternative models
to search for and study homologous genes. In this review, we describe the use of the basal free-living flatworm
Macrostomum lignano as such a model. M. lignano has a number of convenient biological and experimental properties, such as fast reproduction, easy and non-expensive laboratory culturing, optical body transparency, obligatory
sexual reproduction, annotated genome and transcriptome assemblies, and the availability of modern molecular
methods, including transgenesis, gene knockdown by RNA interference, and in situ hybridization. All this makes
M. lignano amenable to the most modern approaches of forward and reverse genetics, such as transposon insertional mutagenesis and methods of targeted genome editing by the CRISPR/Cas9 system. Due to the availability of
an increasing number of genome and transcriptome assemblies of different parasitic flatworm species, new knowledge generated by studying M. lignano can be easily translated to parasitic flatworms with the help of modern
bioinformatic methods of comparative genomics and transcriptomics. In support of this, we provide the results of
our bioinformatics search and analysis of genes homologous between M. lignano and parasitic flatworms, which
predicts a list of promising gene targets for subsequent research.
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Affiliation(s)
- K V Ustyantsev
- Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - V Yu Vavilova
- Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - A G Blinov
- Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - E V Berezikov
- Institute of Cytology and Genetics of Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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Identification and culture of proliferative cells in abnormal Taenia solium larvae: Role in the development of racemose neurocysticercosis. PLoS Negl Trop Dis 2021; 15:e0009303. [PMID: 33750965 PMCID: PMC8016263 DOI: 10.1371/journal.pntd.0009303] [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: 12/24/2020] [Revised: 04/01/2021] [Accepted: 03/10/2021] [Indexed: 11/19/2022] Open
Abstract
Racemose neurocysticercosis is an aggressive disease caused by the aberrant expansion of the cyst form of Taenia solium within the subarachnoid spaces of the human brain and spinal cord resulting in a mass effect and chronic inflammation. Although expansion is likely caused by the proliferation and growth of the parasite bladder wall, there is little direct evidence of the mechanisms that underlie these processes. Since the development and growth of cysts in related cestodes involves totipotential germinative cells, we hypothesized that the expansive growth of the racemose larvae is organized and maintained by germinative cells. Here, we identified proliferative cells expressing the serine/threonine-protein kinase plk1 by in situ hybridization. Proliferative cells were present within the bladder wall of racemose form and absent from the homologous tissue surrounding the vesicular form. Cyst proliferation in the related model species Taenia crassiceps (ORF strain) occurs normally by budding from the cyst bladder wall and proliferative cells were concentrated within the growth buds. Cells isolated from bladder wall of racemose larvae were established in primary cell culture and insulin stimulated their proliferation in a dose-dependent manner. These findings indicate that the growth of racemose larvae is likely due to abnormal cell proliferation. The different distribution of proliferative cells in the racemose larvae and their sensitivity to insulin may reflect significant changes at the cellular and molecular levels involved in their tumor-like growth. Parasite cell cultures offer a powerful tool to characterize the nature and formation of the racemose form, understand the developmental biology of T. solium, and to identify new effective drugs for treatment.
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You H, Jones MK, Whitworth DJ, McManus DP. Innovations and Advances in Schistosome Stem Cell Research. Front Immunol 2021; 12:599014. [PMID: 33746946 PMCID: PMC7973109 DOI: 10.3389/fimmu.2021.599014] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 02/08/2021] [Indexed: 12/14/2022] Open
Abstract
Schistosomes infect about 250 million people globally causing the devastating and persistent disease of schistosomiasis. These blood flukes have a complicated life cycle involving alternating infection of freshwater snail intermediate and definitive mammalian hosts. To survive and flourish in these diverse environments, schistosomes transition through a number of distinct life-cycle stages as a result of which they change their body plan in order to quickly adapt to each new environment. Current research suggests that stem cells, present in adults and larvae, are key in aiding schistosomes to facilitate these changes. Given the recent advances in our understanding of schistosome stem cell biology, we review the key roles that two major classes of cells play in the different life cycle stages during intramolluscan and intramammalian development; these include the germinal cells of sporocysts involved in asexual reproduction in molluscan hosts and the neoblasts of adult worms involved in sexual reproduction in human and other mammalian hosts. These studies shed considerable new light in revealing the stem cell heterogeneity driving the propagation of the schistosome life cycle. We also consider the possibility and value of establishing stem cell lines in schistosomes to advance schistosomiasis research. The availability of such self-renewable resources will provide new platforms to study stem cell behavior and regulation, and to address fundamental aspects of schistosome biology, reproductive development and survival. In turn, such studies will create new avenues to unravel individual gene function and to optimize genome-editing processes in blood flukes, which may lead to the design of novel intervention strategies for schistosomiasis.
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Affiliation(s)
- Hong You
- Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Malcolm K Jones
- Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.,School of Veterinary Science, The University of Queensland, Gatton, QLD, Australia
| | - Deanne J Whitworth
- School of Veterinary Science, The University of Queensland, Gatton, QLD, Australia
| | - Donald P McManus
- Department of Immunology, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
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Kashima M, Agata K, Shibata N. What is the role of PIWI family proteins in adult pluripotent stem cells? Insights from asexually reproducing animals, planarians. Dev Growth Differ 2020; 62:407-422. [PMID: 32621324 DOI: 10.1111/dgd.12688] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 05/26/2020] [Accepted: 06/09/2020] [Indexed: 02/06/2023]
Abstract
Planarians have a remarkable regenerative ability owing to their adult pluripotent stem cells (aPSCs), which are called "neoblasts." Planarians maintain a considerable number of neoblasts throughout their adulthood to supply differentiated cells for the maintenance of tissue homeostasis and asexual reproduction (fission followed by regeneration). Thus, planarians serve as a good model to study the regulatory mechanisms of in vivo aPSCs. In asexually reproducing invertebrates, such as sponge, Hydra, and planaria, piwi family genes are the markers most commonly expressed in aPSCs. While piwi family genes are known as guardians against transposable elements in the germline cells of animals that only sexually propagate, their functions in the aPSC system have remained elusive. In this review, we introduce recent knowledge on the PIWI family proteins in the aPSC system in planarians and other organisms and discuss how PIWI family proteins contribute to the regulation of the aPSC system.
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Affiliation(s)
- Makoto Kashima
- College of Science and Engineering, Aoyama Gakuin University, Sagamihara Chuo Ku, Japan
| | - Kiyokazu Agata
- National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Japan
| | - Norito Shibata
- Department of Integrated Science and Technology, National Institute of Technology, Tsuyama College, Tsuyama-City, Japan
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9
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Nono JK, Lutz MB, Brehm K. Expansion of Host Regulatory T Cells by Secreted Products of the Tapeworm Echinococcus multilocularis. Front Immunol 2020; 11:798. [PMID: 32457746 PMCID: PMC7225322 DOI: 10.3389/fimmu.2020.00798] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 04/07/2020] [Indexed: 01/15/2023] Open
Abstract
Background Alveolar echinococcosis (AE), caused by the metacestode larval stage of the fox-tapeworm Echinococcus multilocularis, is a chronic zoonosis associated with significant modulation of the host immune response. A role of regulatory T-cells (Treg) in generating an immunosuppressive environment around the metacestode during chronic disease has been reported, but the molecular mechanisms of Treg induction by E. multilocularis, particularly parasite immunoregulatory factors involved, remain elusive so far. Methodology/Principal Findings We herein demonstrate that excretory/secretory (E/S) products of the E. multilocularis metacestode promote the formation of Foxp3+ Treg from CD4+ T-cells in vitro in a TGF-β-dependent manner, given that this effect was abrogated by treatment with antibody to mammalian TGF-β. We also show that host T-cells secrete elevated levels of the immunosuppressive cytokine IL-10 in response to metacestode E/S products. Within the E/S fraction of the metacestode we identified an E. multilocularis activin A homolog (EmACT) that displays significant similarities to mammalian Transforming Growth Factor-β (TGF-β/activin subfamily members. EmACT obtained from heterologous expression failed to directly induce Treg expansion from naïve T cells but required addition of recombinant host TGF-β to promote CD4+ Foxp3+ Treg conversion in vitro. Furthermore, like in the case of metacestode E/S products, EmACT-treated CD4+ T-cells secreted higher levels of IL-10. These observations suggest a contribution of EmACT to in vitro expansion of Foxp3+ Treg by the E. multilocularis metacestode. Using infection experiments we show that intraperitoneally injected metacestode tissue expands host Foxp3+ Treg, confirming the expansion of this cell type in vivo during parasite establishment. Conclusion/Significance In conclusion, we herein demonstrate that E. multilocularis larvae secrete factors that induce the secretion of IL-10 by T-cells and contribute to the expansion of TGF-b-driven Foxp3+ Treg, a cell type that has been reported crucial for generating a tolerogenic environment to support parasite establishment and proliferation. Among the E/S factors of the parasite we identified a factor with structural and functional homologies to mammalian activin A which might play an important role in these activities.
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Affiliation(s)
- Justin Komguep Nono
- Institute of Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
- Division of Immunology, Health Science Faculty, University of Cape Town, Cape Town, South Africa
- The Medical Research Centre, Institute of Medical Research and Medicinal Plant Studies, Ministry of Scientific Research and Innovation, Yaounde, Cameroon
| | - Manfred B. Lutz
- Institute of Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Klaus Brehm
- Institute of Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
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10
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James K, Olson PD. The tapeworm interactome: inferring confidence scored protein-protein interactions from the proteome of Hymenolepis microstoma. BMC Genomics 2020; 21:346. [PMID: 32380953 PMCID: PMC7204028 DOI: 10.1186/s12864-020-6710-1] [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: 06/17/2019] [Accepted: 03/30/2020] [Indexed: 12/14/2022] Open
Abstract
Background Reference genome and transcriptome assemblies of helminths have reached a level of completion whereby secondary analyses that rely on accurate gene estimation or syntenic relationships can be now conducted with a high level of confidence. Recent public release of the v.3 assembly of the mouse bile-duct tapeworm, Hymenolepis microstoma, provides chromosome-level characterisation of the genome and a stabilised set of protein coding gene models underpinned by bioinformatic and empirical data. However, interactome data have not been produced. Conserved protein-protein interactions in other organisms, termed interologs, can be used to transfer interactions between species, allowing systems-level analysis in non-model organisms. Results Here, we describe a probabilistic, integrated network of interologs for the H. microstoma proteome, based on conserved protein interactions found in eukaryote model species. Almost a third of the 10,139 gene models in the v.3 assembly could be assigned interaction data and assessment of the resulting network indicates that topologically-important proteins are related to essential cellular pathways, and that the network clusters into biologically meaningful components. Moreover, network parameters are similar to those of single-species interaction networks that we constructed in the same way for S. cerevisiae, C. elegans and H. sapiens, demonstrating that information-rich, system-level analyses can be conducted even on species separated by a large phylogenetic distance from the major model organisms from which most protein interaction evidence is based. Using the interolog network, we then focused on sub-networks of interactions assigned to discrete suites of genes of interest, including signalling components and transcription factors, germline multipotency genes, and genes differentially-expressed between larval and adult worms. Results show not only an expected bias toward highly-conserved proteins, such as components of intracellular signal transduction, but in some cases predicted interactions with transcription factors that aid in identifying their target genes. Conclusions With key helminth genomes now complete, systems-level analyses can provide an important predictive framework to guide basic and applied research on helminths and will become increasingly informative as new protein-protein interaction data accumulate.
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Affiliation(s)
- Katherine James
- Department of Applied Sciences, Northumbria University, Newcastle Upon Tyne, UK. .,Department of Life Sciences, The Natural History Museum, Cromwell Road, London, UK.
| | - Peter D Olson
- Department of Life Sciences, The Natural History Museum, Cromwell Road, London, UK
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Lundström-Stadelmann B, Rufener R, Ritler D, Zurbriggen R, Hemphill A. The importance of being parasiticidal… an update on drug development for the treatment of alveolar echinococcosis. Food Waterborne Parasitol 2019; 15:e00040. [PMID: 32095613 PMCID: PMC7034016 DOI: 10.1016/j.fawpar.2019.e00040] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/06/2019] [Accepted: 02/12/2019] [Indexed: 02/06/2023] Open
Abstract
The lethal disease alveolar echinococcosis (AE) is caused by the metacestode stage of the fox tapeworm Echinococcus multilocularis. Current chemotherapeutical treatment of AE relies on albendazole and mebendazole, with the caveat that these compounds are not parasiticidal. Drugs have to be taken for a prolonged period of time, often life-long, which can cause adverse effects and reduces the patients' quality of life. In some individuals, benzimidazoles are inactive or cause toxicity, leading to treatment discontinuation. Alternatives to benzimidazoles are urgently needed. Over the recent years, in vivo and in vitro models for low-to-medium throughput drug discovery against AE have been set in place. In vitro drug tests include the phosphoglucose-isomerase (PGI) assay to measure physical damage induced to metacestodes, and viability assays to assess parasiticidal activity against metacestodes and stem cells. In vitro models are also employed for studies on mechanisms of action. In vivo models are thus far based on rodents, mainly mice, and benefits could be gained in future by comparative approaches in naturally infected dogs or captive monkeys. For the identification of novel drugs against AE, a rare disease with a low expected market return, drug-repurposing is the most promising strategy. A variety of chemically synthesized compounds as well as natural products have been analyzed with respect to in vitro and/or in vivo activities against AE. We here review and discuss the most active of these compounds including anti-infective compounds (benzimidazoles, nitazoxanide, amphotericin B, itraconazole, clarithromycin, DB1127, and buparvaquone), the anti-infective anti-malarials (artemisinin, ozonids, mefloquine, and MMV665807) and anti-cancer drugs (isoflavones, 2-methoxyestradiol, methotrexate, navelbine, vincristine, kinase inhibitors, metallo-organic ruthenium complexes, bortezomib, and taxanes). Taking into account the efficacy as well as the potential availability for patients, the most promising candidates are new formulations of benzimidazoles and mefloquine. Future drug-repurposing approaches should also target the energy metabolism of E. multilocularis, in particular the understudied malate dismutation pathway, as this offers an essential target in the parasite, which is not present in mammals. Benzimidazoles are used to treat AE, but new drugs are needed. New drugs against AE can be identified by drug repurposing. Drugs against other infectious diseases and cancer can be repurposed against AE. Most promising are new formulations of benzimidazoles and mefloquine. Future approaches should include targeting the energy metabolism of the parasite.
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Affiliation(s)
- Britta Lundström-Stadelmann
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
| | - Reto Rufener
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
| | - Dominic Ritler
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
| | - Raphael Zurbriggen
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
| | - Andrew Hemphill
- Institute of Parasitology, Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Länggassstrasse 122, 3012 Bern, Switzerland
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12
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Gui WF, Xu S, Dang ZS, Zhao YM. In Vitro and in Vivo Effect of Mapk Signal Transduction Pathway Inhibitors on Echinococcus multilocularis. J Parasitol 2019. [DOI: 10.1645/18-121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Wei-feng Gui
- Department of Parasitology, School of Basic Medicine, Guilin Medical University, Guilin, Guangxi 541004, People's Republic of China
| | - Shuo Xu
- Department of Parasitology, School of Basic Medicine, Guilin Medical University, Guilin, Guangxi 541004, People's Republic of China
| | - Zhi-sheng Dang
- Key Laboratory on Biology of Parasite and Vector, Ministry of Health, Shanghai, China; National Center for International Research on Tropical Diseases, Shanghai, China; and WHO Collaborating Center for Tropical Diseases, Shanghai, China; and National
| | - Yu-min Zhao
- Department of Parasitology, School of Basic Medicine, Guilin Medical University, Guilin, Guangxi 541004, People's Republic of China
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13
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Giri BR, Li H, Chen Y, Cheng G. Preliminary evaluation of neoblast-like stem cell factor and transcript expression profiles in Schistosoma japonicum. Acta Trop 2018; 187:57-64. [PMID: 30055172 DOI: 10.1016/j.actatropica.2018.07.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 07/17/2018] [Accepted: 07/24/2018] [Indexed: 11/18/2022]
Abstract
Neoblast-like stem cell factors and transcripts are essential for cell proliferation, self-renewal, and differentiation. Recent studies have demonstrated that nanos, sox, and vasa-like transcription factors are associated with neoblast-like stem cells in Schistosoma mansoni and play crucial roles in the regulation of worm development. However, these neoblast-like stem cell factors and transcripts and their expression profiles remain unknown in Schistosoma japonicum. In this study, we identified orthologs of 11 neoblast-like stem cell factors and transcripts in S. japonicum using bioinformatics and confirmed them by PCR. The expression profiles of neoblast-like stem cell factors and transcripts revealed that some of them were highly expressed in certain stages. Sex-based expression analysis revealed that nanos, polo-like kinase, PCNA, cyclin B, and H2A showed significantly higher expression in female worms, whereas ago and bruli showed higher expression in male worms. In addition, we noted that ago, bruli, and pp32 exhibited higher expression in the testes, while nanos, polo-like kinase, cyclin B, H2A, and H2B showed notable higher expression in both isolated ovaries and testes. Our preliminary results are expected to provide important information about the regulatory roles of these stem cell factors in parasite development and sexual maturation.
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Affiliation(s)
- Bikash Ranjan Giri
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology, Ministry of Agriculture, 518 Ziyue Road, 200241, Shanghai, China
| | - Huimin Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology, Ministry of Agriculture, 518 Ziyue Road, 200241, Shanghai, China
| | - Yongjun Chen
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology, Ministry of Agriculture, 518 Ziyue Road, 200241, Shanghai, China
| | - Guofeng Cheng
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology, Ministry of Agriculture, 518 Ziyue Road, 200241, Shanghai, China.
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14
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Podvyaznaya IM, Galaktionov KV. Reproduction of trematodes in the molluscan host: an ultrastructural study of the germinal mass and brood cavity in daughter rediae of Tristriata anatis Belopolskaia, 1953 (Digenea: Notocotylidae). Parasitol Res 2018; 117:2643-2652. [PMID: 29948202 DOI: 10.1007/s00436-018-5956-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 06/01/2018] [Indexed: 11/24/2022]
Abstract
This study describes the fine structure of the germinal mass in daughter rediae of Tristriata anatis. The germinal mass consists of undifferentiated cells, germinal cells and supporting cells and contains numerous cercarial embryos up to tail bud stage. Supporting cells and their outgrowths form a tight meshwork of the germinal mass. In its basal part, this meshwork serves as scaffolding for undifferentiated and germinal cells, naked cell aggregates and early germinal balls. More mature embryos are located apically. The hypertrophied supporting tissue appears to be involved in an intensive transport of substances, as indicated by abundant gap junctions between cell outgrowths and numerous pinocytotic vesicles and microtubules in their cytoplasm. Germinal cells contain annulate lamellae and the nuage, typical organelles of animal oocytes. In young rediae containing embryonic cercariae at the tail bud stage, the supporting tissue starts to degenerate in the apical part of the germinal mass, and a primordial brood cavity emerges though it develops fully only in mature rediae containing late embryonic cercariae. An unusual feature of the germinal mass in T. anatis rediae is an enhancement of the embryo brooding function. At the same time, the performance of this function by the brood cavity is reduced. This is the first time such a redistribution of the embryo brooding function between the germinal mass and the brood cavity has been reported.
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Affiliation(s)
- Irina M Podvyaznaya
- Zoological Institute of the Russian Academy of Sciences, St. Petersburg, 199034, Russia
| | - Kirill V Galaktionov
- Zoological Institute of the Russian Academy of Sciences, St. Petersburg, 199034, Russia. .,Department of Invertebrate Zoology, St. Petersburg State University, St. Petersburg, 199034, Russia.
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15
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Grubor NM, Jovanova-Nesic KD, Shoenfeld Y. Liver cystic echinococcosis and human host immune and autoimmune follow-up: A review. World J Hepatol 2017; 9:1176-1189. [PMID: 29109850 PMCID: PMC5666304 DOI: 10.4254/wjh.v9.i30.1176] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 08/28/2017] [Accepted: 09/14/2017] [Indexed: 02/06/2023] Open
Abstract
Cystic echinococcosis (CE) is an infectious disease caused by the larvae of parasite Echinococcus granulosus (E. granulosus). To successfully establish an infection, parasite release some substances and molecules that can modulate host immune functions, stimulating a strong anti-inflammatory reaction to carry favor to host and to reserve self-survival in the host. The literature was reviewed using MEDLINE, and an open access search for immunology of hydatidosis was performed. Accumulating data from animal experiments and human studies provided us with exciting insights into the mechanisms involved that affect all parts of immunity. In this review we used the existing scientific data and discuss how these findings assisted with a better understanding of the immunology of E. granulosus infection in man. The aim of this study is to point the several facts that challenge immune and autoimmune responses to protect E. granulosus from elimination and to minimize host severe pathology. Understanding the immune mechanisms of E. granulosus infection in an intermediate human host will provide, we believe, a more useful treatment with immunomodulating molecules and possibly better protection from parasitic infections. Besides that, the diagnosis of CE has improved due to the application of a new molecular tool for parasite identification by using of new recombinant antigens and immunogenic peptides. More studies for the better understanding of the mechanisms of parasite immune evasion is necessary. It will enable a novel approach in protection, detection and improving of the host inflammatory responses. In contrast, according to the "hygiene hypothesis", clinical applications that decrease the incidence of infection in developed countries and recently in developing countries are at the origin of the increasing incidence of both allergic and autoimmune diseases. Thus, an understanding of the immune mechanisms of E. granulosus infection is extremely important.
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Affiliation(s)
- Nikica M Grubor
- Department of Hepatobiliary and Pancreatic Surgery, First Surgical University Hospital, Clinical Center of Serbia, School of Medicine University of Belgrade, 11000 Belgrade, Serbia
| | - Katica D Jovanova-Nesic
- Immunology Research Center, Institute of Virology, Vaccine and Sera-Torlak, 11221 Belgrade, Serbia
- European Center for Peace and Development, University for Peace in the United Nation established in Belgrade, 11000 Belgrade, Serbia.
| | - Yehuda Shoenfeld
- Zabludowicz Center for Autoimmune Diseases, Sheba Medical Center, Tel Aviv University, 5265601 Tel-Hashomer, Tel Aviv, Israel
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16
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Cheng Z, Liu F, Dai M, Wu J, Li X, Guo X, Tian H, Heng Z, Lu Y, Chai X, Wang Y. Identification of EmSOX2, a member of the Sox family of transcription factors, as a potential regulator of Echinococcus multilocularis germinative cells. Int J Parasitol 2017; 47:625-632. [PMID: 28526606 DOI: 10.1016/j.ijpara.2017.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/10/2017] [Accepted: 03/15/2017] [Indexed: 12/20/2022]
Abstract
Larvae of the tapeworm Echinococcus multilocularis cause alveolar echinococcosis (AE), one of the most lethal helminthic infections in humans. The germinative cells, a population of stem cell-like cells, are considered to drive the continuous growth of the metacestodes within the host. The mechanisms and relative molecules controlling the behavior of germinative cells are poorly understood. Sox transcription factors play important roles in maintenance and regulation of stem/progenitor cells. We here describe the identification of a Sox family member in E. multilocularis, EmSOX2, as a potential regulator of germinative cells. Replacement of mouse Sox2 with EmSox2 could derive induced pluripotent stem cells (iPSCs) from somatic cells, suggesting that EmSOX2 is functionally related to mammalian SOX2. EmSOX2 is actively expressed in the proliferating germinative cells in E. multilocularis, and is significantly downregulated upon specific depletion of the germinative cell population by hydroxyurea treatment. These findings suggest that EmSOX2 may play a critical role in regulating E. multilocularis germinative cells.
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Affiliation(s)
- Zhe Cheng
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Fan Liu
- Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Mengya Dai
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Jianjian Wu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Xiu Li
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Xinrui Guo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Huimin Tian
- Medical College, Xiamen University, Xiamen, Fujian 361102, China
| | - Zhijie Heng
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Ying Lu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Xiaoli Chai
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China
| | - Yanhai Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China; Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian 361102, China.
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17
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Cheng Z, Liu F, Li X, Dai M, Wu J, Guo X, Tian H, Heng Z, Lu Y, Chai X, Wang Y. EGF-mediated EGFR/ERK signaling pathway promotes germinative cell proliferation in Echinococcus multilocularis that contributes to larval growth and development. PLoS Negl Trop Dis 2017; 11:e0005418. [PMID: 28241017 PMCID: PMC5344531 DOI: 10.1371/journal.pntd.0005418] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 03/09/2017] [Accepted: 02/16/2017] [Indexed: 12/20/2022] Open
Abstract
Background Larvae of the tapeworm E. multilocularis cause alveolar echinococcosis (AE), one of the most lethal helminthic infections in humans. A population of stem cell-like cells, the germinative cells, is considered to drive the larval growth and development within the host. The molecular mechanisms controlling the behavior of germinative cells are largely unknown. Methodology/Principal findings Using in vitro cultivation systems we show here that the EGFR/ERK signaling in the parasite can promote germinative cell proliferation in response to addition of human EGF, resulting in stimulated growth and development of the metacestode larvae. Inhibition of the signaling by either the EGFR inhibitors CI-1033 and BIBW2992 or the MEK/ERK inhibitor U0126 impairs germinative cell proliferation and larval growth. Conclusions/Significance These data demonstrate the contribution of EGF-mediated EGFR/ERK signaling to the regulation of germinative cells in E. multilocularis, and suggest the EGFR/ERK signaling as a potential therapeutic target for AE and perhaps other human cestodiasis. E. multilocularis is considered as one of the most lethal parasitic helminth in humans. It grows like tumors mainly in human liver and infiltrates other tissues, and even metastasizes. It is believed that the parasite possesses a population of stem cell-like cells, the germinative cells. These cells are totipotent, have the ability for extensive self-renewal, and drive the parasite’s development and growth in the host. However, mechanisms controlling the behavior of germinative cells are poorly understood. Here, we show that the highly conserved EGFR/ERK signaling pathway in the parasite promoted germinative cell proliferation upon addition of human EGF (epidermal growth factor) in vitro, resulting in stimulated growth and development of the parasite. Our study provides information important for understanding this mechanism regulating germinative cells and the complex host-parasite interaction, and we hope it will help in developing new therapeutic strategies for the treatment of human helminthic infections.
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Affiliation(s)
- Zhe Cheng
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Fan Liu
- Medical College, Xiamen University, Xiamen, Fujian, China
| | - Xiu Li
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Mengya Dai
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Jianjian Wu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Xinrui Guo
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Huimin Tian
- Medical College, Xiamen University, Xiamen, Fujian, China
| | - Zhijie Heng
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Ying Lu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Xiaoli Chai
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Yanhai Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- Parasitology Research Laboratory, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
- * E-mail:
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18
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Kern P, Menezes da Silva A, Akhan O, Müllhaupt B, Vizcaychipi KA, Budke C, Vuitton DA. The Echinococcoses: Diagnosis, Clinical Management and Burden of Disease. ADVANCES IN PARASITOLOGY 2017; 96:259-369. [PMID: 28212790 DOI: 10.1016/bs.apar.2016.09.006] [Citation(s) in RCA: 258] [Impact Index Per Article: 36.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The echinococcoses are chronic, parasitic diseases that are acquired after ingestion of infective taeniid tapeworm eggs from certain species of the genus Echinococcus. Cystic echinococcosis (CE) occurs worldwide, whereas, alveolar echinococcosis (AE) is restricted to the northern hemisphere, and neotropical echinococcosis (NE) has only been identified in Central and South America. Clinical manifestations and disease courses vary profoundly for the different species of Echinococcus. CE presents as small to large cysts, and has commonly been referred to as 'hydatid disease', or 'hydatidosis'. A structured stage-specific approach to CE management, based on the World Health Organization (WHO) ultrasound classification of liver cysts, is now recommended. Management options include percutaneous sterilization techniques, surgery, drug treatment, a 'watch-and-wait' approach or combinations thereof. In contrast, clinical manifestations associated with AE resemble those of a 'malignant', silently-progressing liver disease, with local tissue infiltration and metastases. Structured care is important for AE management and includes WHO staging, drug therapy and long-term follow-up for at least a decade. NE presents as polycystic or unicystic disease. Clinical characteristics resemble those of AE, and management needs to be structured accordingly. However, to date, only a few hundreds of cases have been reported in the literature. The echinococcoses are often expensive and complicated to treat, and prospective clinical studies are needed to better inform case management decisions.
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Affiliation(s)
- P Kern
- University Hospital of Ulm, Ulm, Germany
| | | | - O Akhan
- Hacettepe University, Ankara, Turkey
| | - B Müllhaupt
- University Hospital of Zurich, Zürich, Switzerland
| | - K A Vizcaychipi
- National Institute of Infectious Diseases, Buenos Aires, Argentina
| | - C Budke
- Texas A&M University, College Station, TX, United States
| | - D A Vuitton
- Université de Franche-Comté, Besançon, France
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19
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Brehm K, Koziol U. Echinococcus-Host Interactions at Cellular and Molecular Levels. ADVANCES IN PARASITOLOGY 2017; 95:147-212. [PMID: 28131363 DOI: 10.1016/bs.apar.2016.09.001] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The potentially lethal zoonotic diseases alveolar and cystic echinococcosis are caused by the metacestode larval stages of the tapeworms Echinococcus multilocularis and Echinococcus granulosus, respectively. In both cases, metacestode growth and proliferation occurs within the inner organs of mammalian hosts, which is associated with complex molecular host-parasite interactions that regulate nutrient uptake by the parasite as well as metacestode persistence and development. Using in vitro cultivation systems for parasite larvae, and informed by recently released, comprehensive genome and transcriptome data for both parasites, these molecular host-parasite interactions have been subject to significant research during recent years. In this review, we discuss progress in this field, with emphasis on parasite development and proliferation. We review host-parasite interaction mechanisms that occur early during an infection, when the invading oncosphere stage undergoes a metamorphosis towards the metacestode, and outline the decisive role of parasite stem cells during this process. We also discuss special features of metacestode morphology, and how this parasite stage takes up nutrients from the host, utilizing newly evolved or expanded gene families. We comprehensively review mechanisms of host-parasite cross-communication via evolutionarily conserved signalling systems and how the parasite signalling systems might be exploited for the development of novel chemotherapeutics. Finally, we point to an urgent need for the development of functional genomic techniques in this parasite, which will be imperative for hypothesis-driven analyses into Echinococcus stem cell biology, developmental mechanisms and immunomodulatory activities, which are all highly relevant for the development of anti-infective measures.
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Affiliation(s)
- K Brehm
- University of Würzburg, Würzburg, Germany
| | - U Koziol
- University of Würzburg, Würzburg, Germany; Universidad de la República, Montevideo, Uruguay
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20
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Gehrke AR, Srivastava M. Neoblasts and the evolution of whole-body regeneration. Curr Opin Genet Dev 2016; 40:131-137. [PMID: 27498025 DOI: 10.1016/j.gde.2016.07.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Revised: 07/02/2016] [Accepted: 07/13/2016] [Indexed: 11/26/2022]
Abstract
The molecular mechanisms underlying whole-body regeneration are best understood in the planarian flatworm Schmidtea mediterranea, where a heterogeneous population of somatic stem cells called neoblasts provides new tissue for regeneration of essentially any missing body part. Studies on Schmidtea have provided a detailed description of neoblasts and their role in regeneration, but comparatively little is known about the evolutionary history of these cells and their underlying developmental programs. Acoels, an understudied group of aquatic worms that are also capable of extensive whole-body regeneration, have arisen as an attractive group to study the evolution of regenerative processes due to their phylogenetically distant position relative to flatworms. Here, we review the phylogenetic distribution of neoblast cells and compare their anatomical locations, transcriptional profiles, and roles during regeneration in flatworms and acoels to understand the evolution of whole-body regeneration. While the general role of neoblasts appears conserved in species separated by 550 million years of evolution, the extrinsic inputs they receive during regeneration can vary, making the distinction between homology and convergence of mechanism unclear. A more detailed understanding of the precise mechanisms behind whole-body regeneration in diverse phyla is necessary to understand the evolutionary history of this powerful process.
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Affiliation(s)
- Andrew R Gehrke
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Mansi Srivastava
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.
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21
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Schistosomiasis as a disease of stem cells. Curr Opin Genet Dev 2016; 40:95-102. [PMID: 27392295 PMCID: PMC5135665 DOI: 10.1016/j.gde.2016.06.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 05/27/2016] [Accepted: 06/16/2016] [Indexed: 11/24/2022]
Abstract
Schistosomiasis is a devastating parasitic disease caused by flatworms of the genus Schistosoma. The complex life cycles and developmental plasticity of these parasites have captured the attention of parsitologists for decades, yet little is known on the molecular level about the developmental underpinnings that have allowed these worms to thrive as obligate parasites. Here, we describe basic schistosome biology and highlight how understanding the functions of stem cells in these worms will transform our understanding of these parasites. Indeed, we propose that schistosomiasis is fundamentally as disease of stem cells. We hope this review will attract new interest in the basic developmental biology of these important organisms.
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22
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Wang S, Wei W, Cai X. Genome-wide analysis of excretory/secretory proteins in Echinococcus multilocularis: insights into functional characteristics of the tapeworm secretome. Parasit Vectors 2015; 8:666. [PMID: 26715441 PMCID: PMC4696181 DOI: 10.1186/s13071-015-1282-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2015] [Accepted: 12/21/2015] [Indexed: 11/17/2022] Open
Abstract
Background The cestode Echinococcus multilocularis is the causative agent of human alveolar echinococcosis (AE). However, this life-threatening disease is still difficult to treat and control, due to the lack of efficient drugs and vaccines. Excretory/secretory (ES) proteins are crucial for parasite survival and represent potential preferred targets for novel intervention strategies. However, the ES protein features in this parasite have been poorly investigated until now. The current study was carried out to identify and characterise a repertoire of ES proteins in E. multilocularis at the genome-wide level. Methods Here we predicted and functionally annotated the classical and non-classical ES proteins, and comprehensively compared the features and evolution of ES and non-ES proteins in E. multilocularis genome using an integration of bioinformatics tools. The intervention target and antigen potentials as well as the transcription information were also investigated. Results Computational analysis of the E. multilocularis proteins identified 673 putative ES proteins (6.4 %), of which 617 (91.68 %) could be supported by transcription analyses. The predicted ES proteins in E. multilocularis were mostly represented by molecular functions of protease inhibitors, proteases, glycoside hydrolases, immunoglobulin-like folds and growth factors. Analysis of the ratio between synonymous and non-synonymous substitution rates (dN/dS) revealed no significant difference of the evolution selection pressure on ES and non-ES protein coding genes. ES proteins showed higher antigenic density measured by AAR values as compared with the transmembrane proteins but had no significant difference of that feature with intracellular proteins. Additionally, 383 possible ideal drug targets were identified in ES proteins, of which four proteins have corresponding known drugs. Conclusions The present study is the first to identify a repertoire of predicted ES proteins at the genome-wide level in E. multilocularis. The comprehensive analysis provides some novel understanding of the parasite ES protein features and a valuable resource of potential targets for future experimental studies to develop new intervention tools against this parasite. Electronic supplementary material The online version of this article (doi:10.1186/s13071-015-1282-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shuai Wang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Yanchangbu, Lanzhou, 730046, Gansu, China.
| | - Wei Wei
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Yanchangbu, Lanzhou, 730046, Gansu, China.
| | - Xuepeng Cai
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Yanchangbu, Lanzhou, 730046, Gansu, China.
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The Epigenome of Schistosoma mansoni Provides Insight about How Cercariae Poise Transcription until Infection. PLoS Negl Trop Dis 2015; 9:e0003853. [PMID: 26305466 PMCID: PMC4549315 DOI: 10.1371/journal.pntd.0003853] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 05/27/2015] [Indexed: 01/26/2023] Open
Abstract
Background Chromatin structure can control gene expression and can define specific transcription states. For example, bivalent methylation of histone H3K4 and H3K27 is linked to poised transcription in vertebrate embryonic stem cells (ESC). It allows them to rapidly engage specific developmental pathways. We reasoned that non-vertebrate metazoans that encounter a similar developmental constraint (i.e. to quickly start development into a new phenotype) might use a similar system. Schistosomes are parasitic platyhelminthes that are characterized by passage through two hosts: a mollusk as intermediate host and humans or rodents as definitive host. During its development, the parasite undergoes drastic changes, most notable immediately after infection of the definitive host, i.e. during the transition from the free-swimming cercariae into adult worms. Methodology/Principal Findings We used Chromatin Immunoprecipitation followed by massive parallel sequencing (ChIP-Seq) to analyze genome-wide chromatin structure of S. mansoni on the level of histone modifications (H3K4me3, H3K27me3, H3K9me3, and H3K9ac) in cercariae, schistosomula and adults (available at http://genome.univ-perp.fr). We saw striking differences in chromatin structure between the developmental stages, but most importantly we found that cercariae possess a specific combination of marks at the transcription start sites (TSS) that has similarities to a structure found in ESC. We demonstrate that in cercariae no transcription occurs, and we provide evidences that cercariae do not possess large numbers of canonical stem cells. Conclusions/Significance We describe here a broad view on the epigenome of a metazoan parasite. Most notably, we find bivalent histone H3 methylation in cercariae. Methylation of H3K27 is removed during transformation into schistosomula (and stays absent in adults) and transcription is activated. In addition, shifts of H3K9 methylation and acetylation occur towards upstream and downstream of the transcriptional start site (TSS). We conclude that specific H3 modifications are a phylogenetically older and probably more general mechanism, i.e. not restricted to stem cells, to poise transcription. Since adult couples must form to cause the disease symptoms, changes in histone modifications appear to be crucial for pathogenesis and represent therefore a therapeutic target. The blood fluke Schistosoma mansoni causes intestinal bilharzia. The parasite has a complex life cycle in which a freshwater snail serves as intermediate host from which the human infecting larvae hatch. These larvae will actively seek skin contact, penetrate through the epithelium and start developing straight away into adult worms. Development from larvae into adults needs thorough adjustment of gene expression through repositioning or modification of proteins that are associated with DNA (the chromatin). We decided to compare the chromatin of human infective larvae (cercariae), the first developmental stage after infection of the vertebrate host (schistosomula) and adults of S. mansoni. We found that cercariae possess chromatin structures (modifications of histone H3) around the beginning of genes that are very different from schistosomula and adults. We conclude that this structure serves to keep gene transcription in a poised state, i.e. transcription is initiated and can start immediately when the blocking histone modification is removed. A similar type of histone modification was found in embryonic stem cells of vertebrates and our data indicate that it is either a more ancient and/or more general means to poise transcription than previously assumed. Since many parasites possess infective stages that develop rapidly within the host, this particular chromatin structure could be a therapeutic target for a new class of antiparasitic drugs.
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Abstract
Alveolar and cystic echinococcosis, caused by the metacestode larval stages of the tapeworms Echinococcus multilocularis and Echinococcus granulosus, respectively, are life-threatening diseases and very difficult to treat. The introduction of benzimidazole-based chemotherapy, which targets parasite β-tubulin, has significantly improved the life-span and prognosis of echinococcosis patients. However, benzimidazoles show only parasitostatic activity, are associated with serious adverse side effects and have to be administered for very long time periods, underlining the need for new drugs. Very recently, the nuclear genomes of E. multilocularis and E. granulosus have been characterised, revealing a plethora of data for gaining a deeper understanding of host-parasite interaction, parasite development and parasite evolution. Combined with extensive transcriptome analyses of Echinococcus life cycle stages these investigations also yielded novel clues for targeted drug design. Recent years also witnessed significant advancements in the molecular and cellular characterisation of the Echinococcus 'germinative cell' population, which forms a unique stem cell system that differs from stem cells of other organisms in the expression of several genes associated with the maintenance of pluripotency. As the only parasite cell type capable of undergoing mitosis, the germinative cells are central to all developmental transitions of Echinococcus within the host and to parasite expansion via asexual proliferation. In the present article, we will briefly introduce and discuss recent advances in Echinococcus genomics and stem cell research in the context of drug design and development. Interestingly, it turns out that benzimidazoles seem to have very limited effects on Echinococcus germinative cells, which could explain the high recurrence rates observed after chemotherapeutic treatment of echinococcosis patients. This clearly indicates that future efforts into the development of parasitocidal drugs should also target the parasite's stem cell system.
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Affiliation(s)
- U Koziol
- University of Würzburg, Institute of Hygiene and Microbiology, Würzburg, Germany; Sección Bioquímica, Facultad de Ciencias, Universidad de la Republica, Montevideo, Uruguay
| | - K Brehm
- University of Würzburg, Institute of Hygiene and Microbiology, Würzburg, Germany.
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25
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Identification and characterisation of Emp53, the homologue of human tumor suppressor p53, from Echinococcus multilocularis: its role in apoptosis and the oxidative stress response. Int J Parasitol 2015; 45:517-26. [DOI: 10.1016/j.ijpara.2015.02.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 01/29/2015] [Accepted: 02/02/2015] [Indexed: 12/18/2022]
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26
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Breugelmans B, Ansell BRE, Young ND, Amani P, Stroehlein AJ, Sternberg PW, Jex AR, Boag PR, Hofmann A, Gasser RB. Flatworms have lost the right open reading frame kinase 3 gene during evolution. Sci Rep 2015; 5:9417. [PMID: 25976756 PMCID: PMC4894443 DOI: 10.1038/srep09417] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 02/26/2015] [Indexed: 01/08/2023] Open
Abstract
All multicellular organisms studied to date have three right open reading frame kinase genes (designated riok-1, riok-2 and riok-3). Current evidence indicates that riok-1 and riok-2 have essential roles in ribosome biosynthesis, and that the riok-3 gene assists this process. In the present study, we conducted a detailed bioinformatic analysis of the riok gene family in 25 parasitic flatworms (platyhelminths) for which extensive genomic and transcriptomic data sets are available. We found that none of the flatworms studied have a riok-3 gene, which is unprecedented for multicellular organisms. We propose that, unlike in other eukaryotes, the loss of RIOK-3 from flatworms does not result in an evolutionary disadvantage due to the unique biology and physiology of this phylum. We show that the loss of RIOK-3 coincides with a loss of particular proteins associated with essential cellular pathways linked to cell growth and apoptosis. These findings indicate multiple, key regulatory functions of RIOK-3 in other metazoan species. Taking advantage of a known partial crystal structure of human RIOK-1, molecular modelling revealed variability in nucleotide binding sites between flatworm and human RIOK proteins.
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Affiliation(s)
- Bert Breugelmans
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Brendan R E Ansell
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Neil D Young
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Parisa Amani
- Structural Chemistry Program, Eskitis Institute, Griffith University, Brisbane, Australia
| | - Andreas J Stroehlein
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Paul W Sternberg
- HHMI, Division of Biology, California Institute of Technology, Pasadena, California, USA
| | - Aaron R Jex
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Peter R Boag
- Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Victoria, Australia
| | - Andreas Hofmann
- 1] Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia [2] Structural Chemistry Program, Eskitis Institute, Griffith University, Brisbane, Australia
| | - Robin B Gasser
- Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
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27
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Laumer CE, Hejnol A, Giribet G. Nuclear genomic signals of the 'microturbellarian' roots of platyhelminth evolutionary innovation. eLife 2015; 4:e05503. [PMID: 25764302 PMCID: PMC4398949 DOI: 10.7554/elife.05503] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 03/06/2015] [Indexed: 12/25/2022] Open
Abstract
Flatworms number among the most diverse invertebrate phyla and represent the most biomedically significant branch of the major bilaterian clade Spiralia, but to date, deep evolutionary relationships within this group have been studied using only a single locus (the rRNA operon), leaving the origins of many key clades unclear. In this study, using a survey of genomes and transcriptomes representing all free-living flatworm orders, we provide resolution of platyhelminth interrelationships based on hundreds of nuclear protein-coding genes, exploring phylogenetic signal through concatenation as well as recently developed consensus approaches. These analyses robustly support a modern hypothesis of flatworm phylogeny, one which emphasizes the primacy of the often-overlooked 'microturbellarian' groups in understanding the major evolutionary transitions within Platyhelminthes: perhaps most notably, we propose a novel scenario for the interrelationships between free-living and vertebrate-parasitic flatworms, providing new opportunities to shed light on the origins and biological consequences of parasitism in these iconic invertebrates.
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Affiliation(s)
- Christopher E Laumer
- Museum of Comparative Zoology, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, United States
| | - Andreas Hejnol
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen, Norway
| | - Gonzalo Giribet
- Museum of Comparative Zoology, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, United States
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28
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Japa O, Hodgkinson JE, Emes RD, Flynn RJ. TGF-β superfamily members from the helminth Fasciola hepatica show intrinsic effects on viability and development. Vet Res 2015; 46:29. [PMID: 25879787 PMCID: PMC4354977 DOI: 10.1186/s13567-015-0167-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Accepted: 02/25/2015] [Indexed: 12/31/2022] Open
Abstract
The helminth Fasciola hepatica causes fasciolosis throughout the world, a major disease of livestock and an emerging zoonotic disease in humans. Sustainable control mechanisms such as vaccination are urgently required. To discover potential vaccine targets we undertook a genome screen to identify members of the transforming growth factor (TGF) family of proteins. Herein we describe the discovery of three ligands belonging to this superfamily and the cloning and characterisation of an activin/TGF like molecule we term FhTLM. FhTLM has a limited expression pattern both temporally across the parasite stages but also spatially within the worm. Furthermore, a recombinant form of this protein is able to enhance the rate (or magnitude) of multiple developmental processes of the parasite indicating a conserved role for this protein superfamily in the developmental biology of a major trematode parasite. Our study demonstrates for the first time the existence of this protein superfamily within F. hepatica and assigns a function to one of the three identified ligands. Moreover further exploration of this superfamily may yield future targets for diagnostic or vaccination purposes due to its stage restricted expression and functional role.
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Affiliation(s)
- Ornampai Japa
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, Nottingham, LE12 5RD, UK.
| | - Jane E Hodgkinson
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool, L3 5RF, UK.
| | - Richard D Emes
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, Nottingham, LE12 5RD, UK.
- Advanced Data Analysis Centre, University of Nottingham, Sutton Bonington, Nottingham, LE12 5RD, UK.
| | - Robin J Flynn
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, Nottingham, LE12 5RD, UK.
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29
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Cheng Z, Liu F, Zhu S, Tian H, Wang L, Wang Y. A rapid and convenient method for fluorescence analysis of in vitro cultivated metacestode vesicles from Echinococcus multilocularis. PLoS One 2015; 10:e0118215. [PMID: 25705880 PMCID: PMC4337908 DOI: 10.1371/journal.pone.0118215] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Accepted: 01/12/2015] [Indexed: 11/18/2022] Open
Abstract
We here describe a convenient method for preparation, fixation and fluorescence analysis of in vitro cultivated metacestode vesicles from E. multilocularis. Parasite materials could be prepared in one hour, did not need to be sectioned, and were subsequently utilized for further whole-mount staining assays directly. Using these preparations, in combination with conventional fluorescence staining techniques, we could detect the expression and subcellular localization of a specific protein and identify in situ proliferative or apoptotic cells in the germinal layer of metacestode vesicles. Based on this approach, future molecular and cellular analysis of Echinococcus metacestode vesicles in the in vitro system will be greatly facilitated.
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Affiliation(s)
- Zhe Cheng
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Fan Liu
- Medical College, Xiamen University, Xiamen, Fujian, China
| | - Shan Zhu
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Huimin Tian
- Medical College, Xiamen University, Xiamen, Fujian, China
| | - Liang Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Yanhai Wang
- State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
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30
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Geary TG, Sakanari JA, Caffrey CR. Anthelmintic drug discovery: into the future. J Parasitol 2015; 101:125-33. [PMID: 25584662 DOI: 10.1645/14-703.1] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The last half-century has provided all of the (few) drugs currently used to treat human helminthiases. Concern regarding the long-term utility of these drugs, given how readily resistance evolves in the veterinary-agricultural sector, spurs the discovery of new chemical entities. We review the approaches and technologies in use to identify anthelmintics and discuss a number of drug discovery paradigms that may prove pivotal to the next half-century of anthelmintic development.
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Affiliation(s)
- Timothy G Geary
- Institute of Parasitology, McGill University, 21,111 Lakeshore Road, Ste. Anne de Bellevue, Quebec, Canada H9X 3V9
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31
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Orrego-Solano MÁ, Cangalaya C, Nash TE, Guerra-Giraldez C. [Identification of proliferating cells in Taenia solium cysts]. Rev Peru Med Exp Salud Publica 2014; 31:702-706. [PMID: 25597721 PMCID: PMC6108088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2014] [Accepted: 09/24/2014] [Indexed: 06/04/2023] Open
Abstract
Neoblasts are totipotent cells, solely responsible for the proliferation and maturation of tissues in free-living flatworms. Similar cells have been isolated from parasitic flatworms such as Echinococcus. Taenia solium causes human taeniasis (intestinal) and cysticercosis in humans and pigs. Brain infection with larvae (cysts) of T. solium results in neurocysticercosis which is hyperendemic in Peru, and its treatment is associated with serious neurological symptoms. The proliferative capacity and development stages of T. solium have not been described and the neoblasts of this parasite have not been characterized We looked for cell proliferation in T. solium cysts collected from an infected pig, which were identified when replicating and incorporating bromodeoxyuridine nucleotide detected with a monoclonal antibody. A stable cell line of neoblasts would be useful for systematic in vitro studies on drug efficacy and the biology of T. solium.
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Affiliation(s)
- Miguel Ángel Orrego-Solano
- Laboratorio de Inmunopatología en Neurocisticercosis, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. Lima, Perú
- Biólogo
| | - Carla Cangalaya
- Laboratorio de Inmunopatología en Neurocisticercosis, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. Lima, Perú
- tecnóloga médica
| | - Theodore E. Nash
- Laboratorio de Inmunopatología en Neurocisticercosis, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. Lima, Perú
- Laboratory of Parasitic Diseases, National Institutes of Allergy and Infectious Diseases, National Institutes of Health. Bethesda, Maryland, EE. UU
- médico cirujano
| | - Cristina Guerra-Giraldez
- Laboratorio de Inmunopatología en Neurocisticercosis, Laboratorios de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. Lima, Perú
- Departamento de Ciencias Celulares y Moleculares, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. Lima, Perú
- doctora en biología molecular
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Identification and characterization of functional Smad8 and Smad4 homologues from Echinococcus granulosus. Parasitol Res 2014; 113:3745-57. [PMID: 25039015 DOI: 10.1007/s00436-014-4040-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 07/11/2014] [Indexed: 12/18/2022]
Abstract
Smad family proteins are essential cellular mediators of the transforming growth factor-β superfamily. In the present study, we identified two members of the Smad proteins, Smad8 and Smad4 homologues (termed as EgSmadE and EgSmadD, respectively), from Echinococcus granulosus, the causative agent of cystic echinococcosis (CE). Phylogenetic analysis placed EgSmadE in the Smad1, 5, and 8 subgroup of the R-Smad sub-family and EgSmadD in the Co-Smad family. Furthermore, EgSmadE and EgSmadD attained a high homology to EmSmadE and EmSmadD of E. multilocularis, respectively. Both EgSmadE and EgSmadD were co-expressed in the larval stages and exhibited the highest transcript levels in activated protoscoleces, and their encoded proteins were co-localized in the sub-tegumental and tegumental layer of the parasite. As shown by yeast two-hybrid and pull-down analysis, EgSmadE displayed a positive binding interaction with EgSmadD. In addition, EgSmadE localized in the nuclei of Mv1Lu cells (mink lung epithelial cells) upon treatment with human TGF-β1 or human BMP2, indicating that EgSmadE is capable of being translocated into nucleus, in vitro. Our study suggests that EgSmadE and EgSmadD may take part in critical biological processes, including echinococcal growth, development, and parasite-host interaction.
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Petralia RS, Mattson MP, Yao PJ. Aging and longevity in the simplest animals and the quest for immortality. Ageing Res Rev 2014; 16:66-82. [PMID: 24910306 DOI: 10.1016/j.arr.2014.05.003] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 05/08/2014] [Accepted: 05/22/2014] [Indexed: 12/12/2022]
Abstract
Here we review the examples of great longevity and potential immortality in the earliest animal types and contrast and compare these to humans and other higher animals. We start by discussing aging in single-celled organisms such as yeast and ciliates, and the idea of the immortal cell clone. Then we describe how these cell clones could become organized into colonies of different cell types that lead to multicellular animal life. We survey aging and longevity in all of the basal metazoan groups including ctenophores (comb jellies), sponges, placozoans, cnidarians (hydras, jellyfish, corals and sea anemones) and myxozoans. Then we move to the simplest bilaterian animals (with a head, three body cell layers, and bilateral symmetry), the two phyla of flatworms. A key determinant of longevity and immortality in most of these simple animals is the large numbers of pluripotent stem cells that underlie the remarkable abilities of these animals to regenerate and rejuvenate themselves. Finally, we discuss briefly the evolution of the higher bilaterians and how longevity was reduced and immortality lost due to attainment of greater body complexity and cell cycle strategies that protect these complex organisms from developing tumors. We also briefly consider how the evolution of multiple aging-related mechanisms/pathways hinders our ability to understand and modify the aging process in higher organisms.
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Targeting Echinococcus multilocularis stem cells by inhibition of the Polo-like kinase EmPlk1. PLoS Negl Trop Dis 2014; 8:e2870. [PMID: 24901228 PMCID: PMC4046951 DOI: 10.1371/journal.pntd.0002870] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 04/01/2014] [Indexed: 11/19/2022] Open
Abstract
Background Alveolar echinococcosis (AE) is a life-threatening disease caused by larvae of the fox-tapeworm Echinococcus multilocularis. Crucial to AE pathology is continuous infiltrative growth of the parasite's metacestode stage, which is driven by a population of somatic stem cells, called germinative cells. Current anti-AE chemotherapy using benzimidazoles is ineffective in eliminating the germinative cell population, thus leading to remission of parasite growth upon therapy discontinuation. Methodology/Principal findings We herein describe the characterization of EmPlk1, encoded by the gene emplk1, which displays significant homologies to members of the Plk1 sub-family of Polo-like kinases that regulate mitosis in eukaryotic cells. We demonstrate germinative cell-specific expression of emplk1 by RT-PCR, transcriptomics, and in situ hybridization. We also show that EmPlk1 can induce germinal vesicle breakdown when heterologously expressed in Xenopus oocytes, indicating that it is an active kinase. This activity was significantly suppressed in presence of BI 2536, a Plk1 inhibitor that has been tested in clinical trials against cancer. Addition of BI 2536 at concentrations as low as 20 nM significantly blocked the formation of metacestode vesicles from cultivated Echinococcus germinative cells. Furthermore, low concentrations of BI 2536 eliminated the germinative cell population from mature metacestode vesicles in vitro, yielding parasite tissue that was no longer capable of proliferation. Conclusions/Significance We conclude that BI 2536 effectively inactivates E. multilocularis germinative cells in parasite larvae in vitro by direct inhibition of EmPlk1, thus inducing mitotic arrest and germinative cell killing. Since germinative cells are decisive for parasite proliferation and metastasis formation within the host, BI 2536 and related compounds are very promising compounds to complement benzimidazoles in AE chemotherapy. The lethal disease AE is characterized by continuous and infiltrative growth of the metacestode larva of the tapeworm E. multilocularis within host organs. This cancer-like progression is exclusively driven by a population of parasite stem cells (germinative cells) that have to be eliminated for an effective cure of the disease. Current treatment options, using benzimidazoles, are parasitostatic only, and thus obviously not effective in germinative cell killing. We herein describe a novel, druggable parasite enzyme, EmPlk1, that specifically regulates germinative cell proliferation. We show that a compound, BI 2536, originally designed to inhibit the human ortholog of EmPlk1, can also inhibit the parasite protein at low doses. Furthermore, low doses of BI 2536 eliminated germinative cells from Echinococcus larvae in vitro and prevented parasite growth and development. We propose that BI 2536 and related compounds are promising drugs to complement current benzimidazole treatment for achieving parasite killing.
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35
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Boubaker G, Gottstein B, Hemphill A, Babba H, Spiliotis M. Echinococcus P29 antigen: molecular characterization and implication on post-surgery follow-up of CE patients infected with different species of the Echinococcus granulosus complex. PLoS One 2014; 9:e98357. [PMID: 24851904 PMCID: PMC4031130 DOI: 10.1371/journal.pone.0098357] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 05/01/2014] [Indexed: 01/12/2023] Open
Abstract
The protein P29 is a potential serological marker for post-treatment monitoring of cystic echinococcosis (CE) especially in young patients. We now have demonstrated that P29 is encoded in the Echinococcus genus by a single gene consisting of 7 exons spanning 1.2 kb of DNA. Variability of the p29 gene at inter- and intra-species level was assessed with 50 cDNA and 280 genomic DNA clones isolated from different E. granulosus s.l. isolates (E. granulosus sensu stricto (G1), E. equinus (G4), E. ortleppi (G5), E. canadensis (G6), E. canadensis (G7) and E. canadensis (G10)) as well as four E. multilocularis isolates. Scarce interspecies polymorphism at the p29 locus was observed and affected predominantly E. granulosus s.s. (G1), where we identified two alleles (A1 and A2) coding for identical P29 proteins and yielding in three genotypes (A1/A1, A2/A2 and A1/A2). Genotypic frequencies expected under Hardy-Weinberg equilibrium revealed a high rate of heterozygosity (47%) that strongly supports the hypothesis that E. granulosus s.s. (G1) is predominantly outbreeding. Comparative sequence analyses of the complete p29 gene showed that phylogenetic relationships within the genus Echinococcus were in agreement with those of previous nuclear gene studies. At the protein level, the deduced P29 amino acid (AA) sequences exhibited a high level of conservation, ranging from 97.9% AA sequence identity among the whole E. granulosus s.l. group to 99.58% identity among E. multilocularis isolates. We showed that P29 proteins of these two species differ by three AA substitutions without implication for antigenicity. In Western-blot analyses, serum antibodies from a human CE patient infected with E. canadensis (G6) strongly reacted with recombinant P29 from E. granulosus s.s. (G1) (recEg(G1)P29). In the same line, human anti-Eg(G1)P29 antibodies bound to recEcnd(G6)P29. Thus, minor AA sequence variations appear not to impair the prognostic serological use of P29.
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Affiliation(s)
- Ghalia Boubaker
- Institute of Parasitology, University of Berne, Berne, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Berne, Berne, Switzerland
- Department of Clinical Biology B, Laboratory of Parasitology and Mycology, University of Monastir, Monastir, Tunisia
| | - Bruno Gottstein
- Institute of Parasitology, University of Berne, Berne, Switzerland
- * E-mail:
| | - Andrew Hemphill
- Institute of Parasitology, University of Berne, Berne, Switzerland
| | - Hamouda Babba
- Department of Clinical Biology B, Laboratory of Parasitology and Mycology, University of Monastir, Monastir, Tunisia
| | - Markus Spiliotis
- Institute of Parasitology, University of Berne, Berne, Switzerland
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Koziol U, Rauschendorfer T, Zanon Rodríguez L, Krohne G, Brehm K. The unique stem cell system of the immortal larva of the human parasite Echinococcus multilocularis. EvoDevo 2014; 5:10. [PMID: 24602211 PMCID: PMC4015340 DOI: 10.1186/2041-9139-5-10] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 01/30/2014] [Indexed: 12/15/2022] Open
Abstract
Background It is believed that in tapeworms a separate population of undifferentiated cells, the germinative cells, is the only source of cell proliferation throughout the life cycle (similar to the neoblasts of free living flatworms). In Echinococcus multilocularis, the metacestode larval stage has a unique development, growing continuously like a mass of vesicles that infiltrate the tissues of the intermediate host, generating multiple protoscoleces by asexual budding. This unique proliferation potential indicates the existence of stem cells that are totipotent and have the ability for extensive self-renewal. Results We show that only the germinative cells proliferate in the larval vesicles and in primary cell cultures that undergo complete vesicle regeneration, by using a combination of morphological criteria and by developing molecular markers of differentiated cell types. The germinative cells are homogeneous in morphology but heterogeneous at the molecular level, since only sub-populations express homologs of the post-transcriptional regulators nanos and argonaute. Important differences are observed between the expression patterns of selected neoblast marker genes of other flatworms and the E. multilocularis germinative cells, including widespread expression in E. multilocularis of some genes that are neoblast-specific in planarians. Hydroxyurea treatment results in the depletion of germinative cells in larval vesicles, and after recovery following hydroxyurea treatment, surviving proliferating cells grow as patches that suggest extensive self-renewal potential for individual germinative cells. Conclusions In E. multilocularis metacestodes, the germinative cells are the only proliferating cells, presumably driving the continuous growth of the larval vesicles. However, the existence of sub-populations of the germinative cells is strongly supported by our data. Although the germinative cells are very similar to the neoblasts of other flatworms in function and in undifferentiated morphology, their unique gene expression pattern and the evolutionary loss of conserved stem cells regulators suggest that important differences in their physiology exist, which could be related to the unique biology of E. multilocularis larvae.
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Affiliation(s)
| | | | | | | | - Klaus Brehm
- Institute of Hygiene and Microbiology, University of Würzburg, Josef-Schneider-Strasse 2, D-97080 Würzburg, Germany.
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Activities of fenbendazole in comparison with albendazole against Echinococcus multilocularis metacestodes in vitro and in a murine infection model. Int J Antimicrob Agents 2014; 43:335-42. [PMID: 24646943 DOI: 10.1016/j.ijantimicag.2014.01.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 01/14/2014] [Indexed: 11/21/2022]
Abstract
The current chemotherapeutic treatment of alveolar echinococcosis (AE) in humans is based on albendazole and/or mebendazole. However, the costs of treatment, life-long consumption of drugs, parasitostatic rather than parasiticidal activity of chemotherapy, and high recurrence rates after treatment interruption warrant more efficient treatment options. Experimental treatment of mice infected with Echinococcus multilocularis metacestodes with fenbendazole revealed similar efficacy to albendazole. Inspection of parasite tissue from infected and benzimidazole-treated mice by transmission electron microscopy (TEM) demonstrated drug-induced alterations within the germinal layer of the parasites, and most notably an almost complete absence of microtriches. On the other hand, upon in vitro exposure of metacestodes to benzimidazoles, no phosphoglucose isomerase activity could be detected in medium supernatants during treatment with any of these drugs, indicating that in vitro treatment did not severely affect the viability of metacestode tissue. Corresponding TEM analysis also revealed a dramatic shortening/retraction of microtriches as a hallmark of benzimidazole action, and as a consequence separation of the acellular laminated layer from the cellular germinal layer. Since TEM did not reveal any microtubule-based structures within Echinococcus microtriches, this effect cannot be explained by the previously described mechanism of action of benzimidazoles targeting β-tubulin, thus benzimidazoles must interact with additional targets that have not been yet identified. In addition, these results indicate the potential usefulness of fenbendazole for the chemotherapy of AE.
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Podvyaznaya IM, Galaktionov KV. Trematode reproduction in the molluscan host: an ultrastructural study of the germinal mass in the rediae of Himasthla elongata (Mehlis, 1831) (Digenea: Echinostomatidae). Parasitol Res 2014; 113:1215-24. [PMID: 24481901 DOI: 10.1007/s00436-014-3760-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 01/10/2014] [Indexed: 10/25/2022]
Abstract
The germinal mass in Himasthla elongata rediae was studied in detail using transmission electron microscopy. It was shown to be a specialized reproductive organ consisting of germinal cells at various maturation stages, supporting cells and stem cells. The germinal mass also contains early cercarial embryos emerging as a result of cleavage division of mature germinal cells. The stem cells that give rise to germinal cells have heterochromatin-rich nuclei with distinct nucleoli and scarce cytoplasm containing mainly free ribosomes and few mitochondria. The differentiating germinal cells undergo a growth, which is accompanied by an emergence of annulate lamellae and the nuage in their cytoplasm, a noticeable development of RER and Golgi apparatus and an increase in the number of mitochondria. The mitochondria form a large group at one of the cell poles. During differentiation, the nucleus and nucleolus of the germinal cell enlarge while the chromatin becomes gradually less condensed. The supporting tissue of the germinal mass is made up of cells connected by septate junctions. These supporting cells are distinctly different in cellular shape and nuclear ultrastructure. Their outgrowths form a tight meshwork housing stem cells, germinal cells and early cercarial embryos. The cytoplasm of the supporting cells in the mesh area is separated into fine parallel layers by labyrinthine narrow cavities communicating with the intercellular space. The supporting tissue contains differentiating and degenerating cells which indicates its renewal. The results of this ultrastructural study lend support to the hypothesis that the germinal cells of digeneans are germ line cells.
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Affiliation(s)
- Irina M Podvyaznaya
- The Laboratory of Parasitic Worms, Zoological Institute of the Russian Academy of Sciences, Universitetskaya nab., 1, St. Petersburg, 199034, Russia,
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Domínguez MF, Koziol U, Porro V, Costábile A, Estrade S, Tort J, Bollati-Fogolin M, Castillo E. A new approach for the characterization of proliferative cells in cestodes. Exp Parasitol 2014; 138:25-9. [PMID: 24468551 DOI: 10.1016/j.exppara.2014.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Revised: 01/08/2014] [Accepted: 01/16/2014] [Indexed: 10/25/2022]
Abstract
Cestodes show a remarkable proliferative capability that sustains the constant growth and differentiation of proglottids essential for their lifestyle. It is believed that a separate population of undifferentiated stem cells (the so-called germinative cells) are the only cells capable of proliferation during growth and development. The study of this particular cell subpopulation is hampered by the current lack of methods to isolate it. In this work, we developed a reproducible flow cytometry and cell sorting method to quantify and isolate the proliferating cells in the tetrathyridia larvae of the model cestode Mesocestoides corti, based on the DNA content of the cells. The isolated cells display the typical germinative cell morphology, and can be used for RNA isolation with a yield in the ng to μg range. We expect that this approach may facilitate the characterization of the germinative cells in M. corti and other model tapeworms.
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Affiliation(s)
- M F Domínguez
- Sección Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - U Koziol
- Sección Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - V Porro
- Unidad de Biología Celular, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - A Costábile
- Sección Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Departamento de Genética, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - S Estrade
- Sección Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - J Tort
- Departamento de Genética, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - M Bollati-Fogolin
- Unidad de Biología Celular, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - E Castillo
- Sección Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.
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Hemer S, Konrad C, Spiliotis M, Koziol U, Schaack D, Förster S, Gelmedin V, Stadelmann B, Dandekar T, Hemphill A, Brehm K. Host insulin stimulates Echinococcus multilocularis insulin signalling pathways and larval development. BMC Biol 2014; 12:5. [PMID: 24468049 PMCID: PMC3923246 DOI: 10.1186/1741-7007-12-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Accepted: 01/21/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND The metacestode of the tapeworm Echinococcus multilocularis is the causative agent of alveolar echinococcosis, a lethal zoonosis. Infections are initiated through establishment of parasite larvae within the intermediate host's liver, where high concentrations of insulin are present, followed by tumour-like growth of the metacestode in host organs. The molecular mechanisms determining the organ tropism of E. multilocularis or the influences of host hormones on parasite proliferation are poorly understood. RESULTS Using in vitro cultivation systems for parasite larvae we show that physiological concentrations (10 nM) of human insulin significantly stimulate the formation of metacestode larvae from parasite stem cells and promote asexual growth of the metacestode. Addition of human insulin to parasite larvae led to increased glucose uptake and enhanced phosphorylation of Echinococcus insulin signalling components, including an insulin receptor-like kinase, EmIR1, for which we demonstrate predominant expression in the parasite's glycogen storage cells. We also characterized a second insulin receptor family member, EmIR2, and demonstrated interaction of its ligand binding domain with human insulin in the yeast two-hybrid system. Addition of an insulin receptor inhibitor resulted in metacestode killing, prevented metacestode development from parasite stem cells, and impaired the activation of insulin signalling pathways through host insulin. CONCLUSIONS Our data indicate that host insulin acts as a stimulant for parasite development within the host liver and that E. multilocularis senses the host hormone through an evolutionarily conserved insulin signalling pathway. Hormonal host-parasite cross-communication, facilitated by the relatively close phylogenetic relationship between E. multilocularis and its mammalian hosts, thus appears to be important in the pathology of alveolar echinococcosis. This contributes to a closer understanding of organ tropism and parasite persistence in larval cestode infections. Furthermore, our data show that Echinococcus insulin signalling pathways are promising targets for the development of novel drugs.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Klaus Brehm
- University of Würzburg, Institute of Hygiene and Microbiology, Josef-Schneider-Strasse 2, D-97080 Würzburg, Germany.
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Thompson RA, Lymbery AJ. Let's not forget the thinkers. Trends Parasitol 2013; 29:581-4. [DOI: 10.1016/j.pt.2013.10.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 10/10/2013] [Accepted: 10/10/2013] [Indexed: 10/26/2022]
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Development of a cell line from Echinococcus granulosus germinal layer. Acta Trop 2013; 128:124-9. [PMID: 23860182 DOI: 10.1016/j.actatropica.2013.07.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Revised: 06/27/2013] [Accepted: 07/04/2013] [Indexed: 11/22/2022]
Abstract
In vitro culture of parasitic helminths provides an important tool to study cell regeneration and physiology, as well as for molecular biology and genetic engineering studies. In the present study, we established in vitro propagation of cells from Echinococcus granulosus germinal cyst layer. E. granulosus germinal cells grew beyond 100 passages and showed no signs of reduced proliferation capacity. Microscopic analysis revealed that cells grew both attached to the substrate and in suspension, forming three-dimensional structures like mammalian stem cell aggregates. Examination of the chromosome number of attached germinal cells showed a high degree of heteroploidy, suggesting the occurrence of transformation during culture. Monolayer cells survived cryopreservation and were able to proliferate after thawing. Based on the characteristics displayed by E. granulosus germinal cells, we establish a cell line from the E. granulosus germinal layer. Furthermore, we propose that this cell line could be useful for drug screening and for obtaining parasite material.
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Zurabian R, Aguilar-Vega L, Terrones Vargas E, Cervera Hernández ME, Willms K, Ruíz-Velasco Acosta S. In vivo albendazole treatment of Taenia crassiceps cysticerci strain WFU: proliferation, damage, and recovery. Parasitol Res 2013; 112:3961-8. [DOI: 10.1007/s00436-013-3589-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 08/22/2013] [Indexed: 10/26/2022]
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Zheng Y. Strategies of Echinococcus species responses to immune attacks: implications for therapeutic tool development. Int Immunopharmacol 2013; 17:495-501. [PMID: 23973651 DOI: 10.1016/j.intimp.2013.07.022] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 07/26/2013] [Accepted: 07/30/2013] [Indexed: 01/27/2023]
Abstract
Echinococcus species have been studied as a model to investigate parasite-host interactions. Echinococcus spp. can actively communicate dynamically with a host to facilitate infection, growth and proliferation partially via secretion of molecules, especially in terms of harmonization of host immune attacks. This review systematically outlines our current knowledge of how the Echinococcus species have evolved to adapt to their host's microenvironment. This understanding of parasite-host interplay has implications in profound appreciation of parasite plasticity and is informative in designing novel and effective tools including vaccines and drugs for the treatment of echinococcosis and other diseases.
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Affiliation(s)
- Yadong Zheng
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, CAAS, Lanzhou, Gansu, China; Key Lab of New Animal Drug Project, Gansu Province, Lanzhou Institute of Husbandry, Pharmaceutical Sciences, CAAS, Lanzhou, Gansu, China; Key Lab of Veterinary Pharmaceutical Development, Ministry of Agriculture, Lanzhou Institute of Husbandry, Pharmaceutical Sciences, CAAS, Lanzhou, Gansu, China.
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Affiliation(s)
- James J. Collins
- Howard Hughes Medical Institute and Department of Cell and Developmental Biology, Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Phillip A. Newmark
- Howard Hughes Medical Institute and Department of Cell and Developmental Biology, Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- * E-mail:
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Cytosine methylation is a conserved epigenetic feature found throughout the phylum Platyhelminthes. BMC Genomics 2013; 14:462. [PMID: 23837670 PMCID: PMC3710501 DOI: 10.1186/1471-2164-14-462] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 07/03/2013] [Indexed: 12/22/2022] Open
Abstract
Background The phylum Platyhelminthes (flatworms) contains an important group of bilaterian organisms responsible for many debilitating and chronic infectious diseases of human and animal populations inhabiting the planet today. In addition to their biomedical and veterinary relevance, some platyhelminths are also frequently used models for understanding tissue regeneration and stem cell biology. Therefore, the molecular (genetic and epigenetic) characteristics that underlie trophic specialism, pathogenicity or developmental maturation are likely to be pivotal in our continued studies of this important metazoan group. Indeed, in contrast to earlier studies that failed to detect evidence of cytosine or adenine methylation in parasitic flatworm taxa, our laboratory has recently defined a critical role for cytosine methylation in Schistosoma mansoni oviposition, egg maturation and ovarian development. Thus, in order to identify whether this epigenetic modification features in other platyhelminth species or is a novelty of S. mansoni, we conducted a study simultaneously surveying for DNA methylation machinery components and DNA methylation marks throughout the phylum using both parasitic and non-parasitic representatives. Results Firstly, using both S. mansoni DNA methyltransferase 2 (SmDNMT2) and methyl-CpG binding domain protein (SmMBD) as query sequences, we illustrate that essential DNA methylation machinery components are well conserved throughout the phylum. Secondly, using both molecular (methylation specific amplification polymorphism, MSAP) and immunological (enzyme-linked immunoabsorbent assay, ELISA) methodologies, we demonstrate that representative species (Echinococcus multilocularis, Protopolystoma xenopodis, Schistosoma haematobium, Schistosoma japonicum, Fasciola hepatica and Polycelis nigra) within all four platyhelminth classes (Cestoda, Monogenea, Trematoda and ‘Turbellaria’) contain methylated cytosines within their genome compartments. Conclusions Collectively, these findings provide the first direct evidence for a functionally conserved and enzymatically active DNA methylation system throughout the Platyhelminthes. Defining how this epigenetic feature shapes phenotypic diversity and development within the phylum represents an exciting new area of metazoan biology.
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Koziol U, Krohne G, Brehm K. Anatomy and development of the larval nervous system in Echinococcus multilocularis. Front Zool 2013; 10:24. [PMID: 23642192 PMCID: PMC3658878 DOI: 10.1186/1742-9994-10-24] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 04/30/2013] [Indexed: 01/06/2023] Open
Abstract
Background The metacestode larva of Echinococcus multilocularis (Cestoda: Taeniidae) develops in the liver of intermediate hosts (typically rodents, or accidentally in humans) as a labyrinth of interconnected cysts that infiltrate the host tissue, causing the disease alveolar echinococcosis. Within the cysts, protoscoleces (the infective stage for the definitive canid host) arise by asexual multiplication. These consist of a scolex similar to that of the adult, invaginated within a small posterior body. Despite the importance of alveolar echinococcosis for human health, relatively little is known about the basic biology, anatomy and development of E. multilocularis larvae, particularly with regard to their nervous system. Results We describe the existence of a subtegumental nerve net in the metacestode cysts, which is immunoreactive for acetylated tubulin-α and contains small populations of nerve cells that are labeled by antibodies raised against several invertebrate neuropeptides. However, no evidence was found for the existence of cholinergic or serotoninergic elements in the cyst wall. Muscle fibers occur without any specific arrangement in the subtegumental layer, and accumulate during the invaginations of the cyst wall that form brood capsules, where protoscoleces develop. The nervous system of the protoscolex develops independently of that of the metacestode cyst, with an antero-posterior developmental gradient. The combination of antibodies against several nervous system markers resulted in a detailed description of the protoscolex nervous system, which is remarkably complex and already similar to that of the adult worm. Conclusions We provide evidence for the first time of the existence of a nervous system in the metacestode cyst wall, which is remarkable given the lack of motility of this larval stage, and the lack of serotoninergic and cholinergic elements. We propose that it could function as a neuroendocrine system, derived from the nervous system present in the bladder tissue of other taeniids. The detailed description of the development and anatomy of the protoscolex neuromuscular system is a necessary first step toward the understanding of the developmental mechanisms operating in these peculiar larval stages.
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Affiliation(s)
- Uriel Koziol
- University of Würzburg, Institute of Hygiene and Microbiology, Josef-Schneider-Strasse 2, Würzburg, D-97080, Germany.
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Pouchkina-Stantcheva NN, Cunningham LJ, Hrčkova G, Olson PD. RNA-mediated gene suppression and in vitro culture in Hymenolepis microstoma. Int J Parasitol 2013; 43:641-6. [PMID: 23639265 DOI: 10.1016/j.ijpara.2013.03.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 03/14/2013] [Accepted: 03/17/2013] [Indexed: 02/01/2023]
Abstract
Hymenolepis microstoma, the mouse bile-duct tapeworm, is a classical rodent-hosted model that provides easy laboratory access to all stages of the life cycle. Recent characterisation of its genome has greatly advanced its utility for molecular research, albeit contemporary techniques such as those for assaying gene function have yet to be developed in the system. Here we present research on the development of RNA-mediated gene suppression via RNA interference (RNAi), and on in vitro culture of the enteric, adult phase of the life cycle to support this work. We demonstrate up to 80% quantitative suppression of a Hox transcript via soaking activated juvenile worms with double-stranded RNAs. However, we were unable to achieve segmentation of the worms in culture despite extensive manipulations of the culture media and supplements, preventing functional interpretation. An alternative, in vivo approach to RNAi was also tested by exposing cysticercoids prior to inoculation in mice, but fluorescent labelling showed that the RNAs did not sufficiently penetrate the cyst body and no difference in expression was found between exposed and control groups grown in vivo. Genomic and transcriptomic data revealed that H. microstoma has two orthologs each of Dicer, Drosha and Ago-1-like genes and that expression of one of the Ago-1 genes appears exclusive to germline development, suggesting that two or more independent RNA-mediated pathways are in operation. These studies demonstrate the viability of RNAi in H. microstoma and extend the utility of the model for research in the genomic era.
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Abstract
Schistosomes are parasitic flatworms that cause schistosomiasis, a neglected tropical disease that affects hundreds of millions worldwide. Treatment and control of schistosomiasis relies almost entirely on the single drug praziquantel (PZQ), making the prospect of emerging drug resistance particularly worrisome. This review will survey reports of PZQ (and other drug) resistance in schistosomes and other platyhelminths, and explore mechanisms by which drug resistance might develop. Newer genomic and post-genomic strategies that offer the promise of better understanding of how drug resistance might arise in these organisms will be discussed. These approaches could also lead to insights into the mode of action of these drugs and potentially provide markers for monitoring the emergence of resistance.
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50
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The genomes of four tapeworm species reveal adaptations to parasitism. Nature 2013; 496:57-63. [PMID: 23485966 PMCID: PMC3964345 DOI: 10.1038/nature12031] [Citation(s) in RCA: 507] [Impact Index Per Article: 46.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 02/21/2013] [Indexed: 01/27/2023]
Abstract
Tapeworms cause debilitating neglected diseases that can be deadly and often require surgery due to ineffective drugs. Here we present the first analysis of tapeworm genome sequences using the human-infective species Echinococcus multilocularis, E. granulosus, Taenia solium and the laboratory model Hymenolepis microstoma as examples. The 115-141 megabase genomes offer insights into the evolution of parasitism. Synteny is maintained with distantly related blood flukes but we find extreme losses of genes and pathways ubiquitous in other animals, including 34 homeobox families and several determinants of stem cell fate. Tapeworms have species-specific expansions of non-canonical heat shock proteins and families of known antigens; specialised detoxification pathways, and metabolism finely tuned to rely on nutrients scavenged from their hosts. We identify new potential drug targets, including those on which existing pharmaceuticals may act. The genomes provide a rich resource to underpin the development of urgently needed treatments and control.
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