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Malformations/anomalies in the development of cestodes
Aliaskerova, Madina ; Schreiber, Manfred (advisor) ; Chanová, Marta (referee)
Anomalies in tapeworms can appear spontaneously under natural conditions, at both morphological and developmental level. In adult tapeworms, malformations at morphological level are manifested on the scolex and strobila. Their detailed description can be found in Taenia saginata, Taenia pisiformis, Taenia solium, Dibothriocephalus nihonkaiense, Dibothriocephalus latus, Hymenolepis nana and Hymenolepis microstoma. In the larval stages of Taenia crassiceps, the malformations occur predominantly on the skolex. Morphological malformations may be manifested by multiplication of suckers or change in the appearance and number of hooks, change in the structure of the genitalia, occurrence of lateral segments, fenestration of the strobila or occurrence of multiple planes of symmetry. However, these malformations can also be caused by targeted radiation exposure, temperature stress or anthelmintics. Developmental anomalies are also manifested by spontaneous appearance of tapeworms in different parts of the body in different host species. There is a link between anomalous infections and the immune status of the host. Possible causes of anomalies include damage to neoblasts, lack of a proper immune response by the host, anthelmintics, host diet, or environmental influences.
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Isolation and characterisation of extracellular vesicles of parasitic helminths
MAZANEC, Hynek
Excretory-secretory products (ESP) serve as important mediators of intercellular and inter-species communication. They were originally thought to be secreted mainly in a soluble form, but recent discoveries indicate their delivery through extracellular vesicles (EVs). These membraneous particles provide protection from degradation for some of their components, as well as targeted delivery through various receptors on their surface. As such they have been studied as potent immunomodulators in host-pathogen relationships. With respect to parasitic helminths, EVs are being studied as agents for diagnosis, vaccination or therapeutics. However, their general biology, especially their biogenesis patterns, is still poorly understood compared to their functional role.Therefore, the goal of this thesis is to investigate in more detail the secretion activity of EVs in different tapeworms and their life-cycle stages. Under laboratory conditions, the life cycle of Schistocephalus solidus, a tapeworm with an aquatic life cycle, was established to explore EVs secretion at different developmental stages. Moreover, we used proteomic analyses and ultrastructural observations to identify the main biogenesis pathways behind EVs secretion in a terrestrial tapeworm Hymenolepis diminuta. This also allowed for the comparison of EVs generation in tapeworms with different host types.
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Transcriptomic analysis of Mesocestoides corti
Korená, Lucie ; Leontovyč, Roman (advisor) ; Převorovský, Martin (referee)
Some species of parasites, including helminths, can inhibit carcinogenesis in their hosts. The antitumoral effect has been discovered in the tapeworms Taenia crassiceps and Echinococcus granulosus, which genes associated with cancer regression have been identified. The effect of melanoma suppression has also been observed in tapeworm Mesocestoides corti by the Laboratory of Helminthology, Department of Parasitology, Faculty of Science, Charles University, however the mechanism-of-action, remains unknown. For the upcoming research it was essential to have the complex molecular data such as transcriptome of the developmental stage s of M. corti. This work is focused on the transcriptomic profiling of the tapeworm M. corti and the differential gene expression in two different strains of murine hosts (inbred and outbred) using the RNA-Seq. The main goal was to identify upregulated transcripts in the tapeworms from the murine hosts that could have a potential effect on cancer regression. Differential gene expression analysis was performed, and the results showed that tapeworms in murine hosts (regardless of strain) had more upregulated transcripts than tapeworms cultured in vitro. Analysis of highly upregulated transcripts in the tapeworms that were grown in the murine hosts identified several...
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Migration and pathogenicity of neurotropic helminths
Pech, Václav ; Horák, Petr (advisor) ; Chanová, Marta (referee)
A neurotropism of helminths can be observed in their intermediate, paratenic and definitive hosts. Neurotropic helminths migrate through the nervous tissue, where maturation and reproduction can take place. The neurotropic helminths can be found in the family of trematodes (Diplostomum baeri, D. phoxini, Ornithodiplostomum ptychocheilus, Trichobilharzia regenti), cestodes (Taenia multiceps, T. solium) and nematodes (Angiostrongylus cantonensis, Elaphostrongylus cervi, Parelaphostronglus tenuis, Baylisascaris procyonis). Presence of these helminths in the nervous tissue can (usually with contribution of the immune system) lead to neurological or other pathological changes: the infected hosts can even die. Some of the neurotropic helminths (A. cantonensis, B. procyonis, T. solium, T. multiceps) can infect humans as well.
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In vitro cultivation of tapeworm Hymenolepis diminuta - 2
Jandura, Dominik ; Vokřál, Ivan (advisor) ; Raisová Stuchlíková, Lucie (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Dominik Jandura Supervisor: PharmDr. Ivan Vokřál, Ph.D. Title of diploma thesis: In vitro cultivation of tapeworm Hymenolepis diminuta - 2 Aim of this diploma thesis was to obtain cycticercoids of the rat tapeworm (Hymenolepis diminuta), excyst them and find out the conditions for the maximal in vitro incubation period. As the intermediate host mealworm beetle (Tenebrio molitor) infected by the rat feces containing tapeworm eggs was used. Excystment was done using L-cystein and sodium tauroglycocholate. Excysted larvae were cultured in vitro (37 řC, 5 % CO2) in RPMI 1640 medium enriched with other substances chosen according previously published methods. Mainly sheep, mouse or rat liver extracts eventually in combination with yeast extract and sheep bile were used. The effect of tested substances on the cultivation was evaluated by measuring of the tapeworm's growth. The best effect on the grow of the tapeworms was observed using medium containing serum, yeast extract and sheep liver extract where tapeworms achieved length of 1561 µm after 16 days of incubation. The further growth was limited by appearance of pathologic formations.
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Influence of tissue helminths on the development of cancers in model organisms
Schreiber, Manfred ; Horák, Petr (advisor) ; Kolářová, Libuše (referee)
Mesocestoides corti and Taenia crassiceps are tapeworms, larvae of which are characterized by their ability to reproduce asexually. In this work, the effect of infection by M. corti and T. crassiceps in BALB/c, C57BL/6J and ICR mice on the growth and metastasis of B16F10 melanoma tumors was investigated. Although an increase in metastatic activities was observed after intravenous administration of melanoma cells to M. corti-infected mice, both tapeworms showed a strong suppressive effect on the size and number of tumors and metastases formed when the cells were administered intraperitoneally. This, in some cases, led to a complete elimination of tumor cells. In vitro cultivation of B16F10 cells in the presence of larval excretory-secretory products led to a decrease in their viability but an increase in their migration ability. Flow cytometry proved that M. corti infection has an effect on the increased number and proportion of macrophage populations in the peritoneum of ICR mice. Our work confirmed the anti-tumor effect of T. crassiceps infection in mice and introduced M. corti as a new helminth species capable of influencing cancer. Key words: helminths, cestodes, cancers, Mesocestoides corti, Taenia crassiceps
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Endoparazitózy ovcí na konvenčních farmách a biofarmách
Vomáčková, Karolína
The aim of this thesis is to assess the difference in prevalence of endoparasites in sheep bred on conventional farms and on organic farms. The theoretic part consists of a literary research on the basis of both domestic and foreign literature dealing with the problem of endoparasitic nematodes, tapeworms and coccidia in sheep. According to this research it is possible to identify seven perilous species of coccidia, fourteen species of intestinal nematodes, two species of lung nematodes, two species of tapeworms and two species of trematodes in the Czech Republic. The practical observations were carried out using nondestructive coprological techniques throughout the year 2016. Four species of coccidia (Eimeria bakuensis, Eimeria ovinoidalis, Eimeria parva, Eimeria crandalis), seven species of intestinal nematodes (Haemonchus concortus, Trychostrongylus spp.axei, Nematodirus spp., Cooperia curticei, Bunostomum trigonocephalum, Chaberia ovina, Oesophagostomum venulosum), one species of lung nematodes (Protostrongylus rufescens) and one species of tapeworms (Moniezia expansa) have been identified during the analysis. The prevalence of parasites and intensity of infection differed according to the type of farming, type of sheep care (incl. deworming) and also time of year. In total the organic farming has been assessed the healthier farming type. The practical outcome therefore is a recommendation for conventional farms to pay more attention to the sheep care with respect to the life cycles of the parasites.
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Vliv chovatelského prostředí na výskyt endoparazitů ovcí na Tišnovsku
Vomáčková, Karolína
The aim of this thesis was to survey the problem of endoparasitic nematode, cestode, trematode and coccidia infections in sheep and their connection with the farming conditions and zoo-hygienic care. We have found out that 7 species of coccidia, 14 species of gastrointestinal nematodes, three species of lung nematodes, two species of cestodes and four species of trematodes can be found in local conditions. Further we discussed possible ways of suppressing the infections in the breeding environment. The practical coprological examination took place in autumn 2018. We've examined fecal samples from 10 different sheep farms in the Tišnov region, 100 samples in total. We've discovered four species of coccidia (Eimeria bakuensis, E. crandalis, E. parva, E. ovinoidalis), eight species of gastrointestinal nematodes (Bunostomum trigonocephalum, Cooperia curticei, Haemonchus contortus, Chabertia ovina, Nematodirus spp., Oesophagostomum venulosum, Trichuris ovis, Trichostrongylus spp.), two species of lung nematodes (Muellerius ca¬pillaris, Protostrongylus rufescens) and one cestode species (Moniezia expansa). Prevalence and intensity of the infection varied greatly among the farms. We concluded that administering feed supplements during lambing had the most noticeable positive effect on the infection course.
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Helminths as causative agents of vertebrate cancers
Schreiber, Manfred ; Horák, Petr (advisor) ; Kolářová, Iva (referee)
Opisthorchis viverrini, Clonorchis sinensis, and Schistosoma haematobium have been classified as the group 1 of carcinogens by the International Agency for Research on Cancer. Infections with opisthorchid flukes may lead to the development of cholangiocarcinoma of the liver, and those with schistosomes to the squamous carcinoma of the bladder. The link between helminth infections and carcinomas has been confirmed, and the exact mechanisms of carcinoma induction are at present intensively studied. There are some other representatives of helminths that are probably associated with cancers, but their direct effect on the process of carcinogenesis has not been confirmed yet. The formation of tumors can also occur via malignant transformation of totipotent parasite cells that become invasive and metastasize to different parts of the host body. However, some types of helminths may exhibit an opposite effect and show an anti-tumor activity. This review primarily focuses on the helminths associated with the development of cancer and the currently described mechanisms of carcinogenesis caused by such infections.
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