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Helminths in the mammalian lungs: migration strategies and pathology
Butula, Dan ; Majer, Martin (advisor) ; Novák, Jan (referee)
This bachelor thesis summarizes the knowledge about the migration strategies of medically important pulmonary helminths and their laboratory models and describes the pulmonary pathology caused by these helminths. Helminths typically enter the lungs within hours or days after infection and often migrate from the lungs to other body organs. Certain species migrate through the lungs intravascularly (schistosome larvae and in certain cases filarial larvae), but others enter the lung parenchyma directly (roundworm larvae, Strongyloides hookworms, adults of Paragonimus flukes, and the metacestode of the tapeworm Echinococcus) or colonise the pleural cavity (adults of Litomosoides sigmodontis and young adults of Paragonimus flukes). This, together with the time spent in the lungs, influences the pathology caused. During this time, mechanical damage to the lung tissue, granuloma formation, infiltration of immune cells, emphysema formation, remodelling of lung tissue and blood vessels, and more can occur. Excretory secretory products of helminths contribute significantly to the pathology, which, among other things, are used as a tool to modulate host immunity and shape the migratory pathway through the lungs. This topic is of particular importance in terms of elucidating the pulmonary processes that are...
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Sledování imunomodulačních účinků extraktů z helminta na makrofágové buněčné kultuře
ŘEŽÁBKOVÁ, Lucie
The main aim of the present study was to determine the immunomodulatory effects of extracts obtained from the commensal helminth, Hymenolepis diminuta, on in vitro rat macrophages. Here, I tested two types of crude extracts derived from various tapeworm's life stages (larval stages, adults) and excretory/secretory products (ES-products). The in vitro inflammatory model was induced by bacterial lipopolysaccharides (LPS) to compare the results with normal state of macrophages. To monitoring immune response, I analysed the relative gene expressions of several cytokines TNF, IL-10, IL-1; signal transducer and activator of transcription STAT6 as well as IL-17re using by qPCR. The presence of adult extracts caused no obvious immune response of macrophages. The larval extract and ES-products induced an inflammatory response. All three types of compounds derived from H. diminuta reduced the inflammation of macrophages influenced by LPS.
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Host manipulation as a helminth strategy increasing the probability of further transmission
Urbanová, Monika ; Horák, Petr (advisor) ; Bulantová, Jana (referee)
The manipulation hypothesis deals with the ability of some parasitic organisms to efficiently change the phenotype of their hosts to facilitate their transmission. The parasite thus gains a selective advantage and, compared to non-manipulating species, is more reproductive. This phenomenon can also be observed in some parasitic helminths. The objects of helminth manipulation are most often invertebrates, who serve as intermediate hosts. In infected animals, we can observe striking morphological changes, abnormal movement reactions, or even suicidal tendencies. The objects of helminth manipulation are most often invertebrates, who serve as intermediate hosts. Manipulation can be divided into direct and indirect, depending on whether the parasite is able to act directly on the nervous tissue of the host. The desired behavioral response can be elicited in other ways, for example, by disrupting the host's metabolism or through complex interactions with the immune system. This thesis focuses mainly on the presentation of various strategies that are most often described in helminth manipulators. Key words: Helminth, host, infection, manipulation, behavioral change, extended phenotype
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Imunomodulační účinky extraktů z helminta na střevní buněčnou linii potkaního modelu
LEVÁ, Jana
In this study, we examined the immunomodulatory effect of excretory/secretory products, crude adult extracts and crude larvae extracts from Hymenolepis diminuta on the intestinal epithelilal cell line from a rat. For determination of the immunomodulation effect of all H. diminuta extracts was used relative gene expression of TNFa, IL-17re and IL-33 from epithelial cells and it was tested using real-time PCR. Our result showed that excretory/secretory products had the strongest antiinflammatory effect on the epithelial cells. We assume that crude adult extracts play an important role in increase of gene expression of IL-33 and also in the immunomodulatory ability of H. diminuta in the host organism.
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Zavedení helminta jako modelového organismu do kultury a charakterizace imunitní odpovědi hostitele
HLOŽKOVÁ, Oldřiška
The main goals of the present thesis were (i) to introduce a model commensal tapeworm, Hymenolepis diminuta, to the culture and (ii) characterization of a mucosal immune response in the host gut. Primarily, I focused on the establishment of a culture of H. diminuta under laboratory conditions based on its natural life cycle - grain beetles (Tenebrio molitor) as an intermediate host and outbred Wistar rats as definitive hosts. Infected beetles were bred at 28°C and due to this specific condition we were able to get infectious larvae three weeks after the first infection. To meet the second aim of this study, I examined a production of IgA antibodies against H. diminuta in the intestine of definitive host in the fecal samples using an indirect ELISA method. First, I performed several experiments focused on the optimization of H. diminuta antigen suitable for detection of IgA antibodies against H. diminuta in ELISA. Subsequently, I performed two experiments for detection of IgA fluctuation during H. diminuta infection in the rat model system. The strong production of IgA antibodies started always in the patent period of infection (i.e., when adult tapeworm is developed). In summary, my results suggest that H. diminuta has a strong immunomodulatory effect on the host organism.
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The role of nitric oxide in helminthoses
Šmídová, Barbora ; Macháček, Tomáš (advisor) ; Leštinová, Tereza (referee)
Nitric oxide (NO) is a small gaseous molecule produced mainly by activated macrophages, but some other cells as well, in reaction to an infection. Since late 80s, when the effect of NO on schistosomes was demonstrated, many experiments have been conducted examining both the effect of NO on other helminths and its role in helminthoses. In vitro experiments center mainly upon direct effects of NO on helminths - loss of motility and viability in particular. On the other hand, in vivo studies focus on the course of infection and pathological changes in hosts. However, in vitro and in vivo data do not always corroborate. Moreover, the effects of NO differ not only across helminth genera but also for developmental stages of the same parasite.
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Orientation of helminths during host seeking
Vojtová, Terezie ; Mikeš, Libor (advisor) ; Horák, Petr (referee)
The parasitic helminths are often forced in the environment to search for their host quickly in order to continue the ontogenetic development, or else to finish it. To search for and indentify the host, they use various types of receptors which allow them to provoke a taxes corresponding to the oncoming stimulus and to react regarding the current situation. In respect to the concept relevant to the helminths, this work concerns trematodes, whose freely movable stadia are miracidium and cercacia, and then monogeneans which are viparous or oviparous with oncomiracidium larva, and nematodes during which the third larva stage moves. The representatives of the groups of Myxozoans and Ciliophorea are also mentionned, since they use similar mechanisms to look for hosts as helminths. This thesis includes the summary of the existing knowledge related to the orientation of helminths in the environment. On the basis of the data that is already known, it is possible to compare which mechanisms are used for host-seeking by particular species, and according to which signals from the surroundings they most often orientate themselves. Powered by TCPDF (www.tcpdf.org)
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Orientation of helminths during host seeking
Vojtová, Terezie ; Mikeš, Libor (advisor) ; Horák, Petr (referee)
Helminths are often forced in the environment to search for their host quickly in order to continue the ontogenetic development, or else to finish it. To search for and indentify the host, they use various types of receptors which allow them to provoke a taxes corresponding to the oncoming stimulus and to react to the presence of the host. This thesis includes the summary of the existing knowledge related to the orientation of helminths, the comparison of the mechanisms used by the searching of a host and signals in the environment. In respect to the concept relevant to the helminths, this work concerns trematodes, whose freely movable stadia are miracidium and cercaria, and then monogeneans which are viparous or oviparous with oncomiracidium larva, and nematodes with the third infective larva stage. The representatives of fish parasites of Myxozoans and Ciliophorea are also mentionned, since they use similar mechanisms to look for hosts as helminths. Powered by TCPDF (www.tcpdf.org)
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Peroral infections of birds and mammals with the neuropathogenic fluke Trichobilharzia regenti
Pech, Václav ; Horák, Petr (advisor) ; Blažová, Kateřina (referee)
Migration within the body of an infected host is one of the most important parts in the life cycle of flukes, including schistosomes. Migration of avian and mammalian visceral schistosomes has been a quite well studied topic (Haas a Haeberlein, 2009), which became more attractive after the discovery of T. regenti, an avian schistosome which is able to migrate through the nervous tissues of infected birds and mammals as well. Migration of T. regenti and T. szidati schistosomula within the definitive (duck) and the accidental (mouse) hosts is the main topic of the diploma thesis. This work continues with the research of K. Blažová (Faculty of Science, Charles University in Prague) who studied migration of T. regenti within the definitive hosts infected perorally with cercariae or hepatopancreases of the infected intermediate snail, Radix lagotis (unpblished). She proved that T. regenti schistosomula are able to use the central nervous system for migration to the nasal mucosa of infected birds. In our work, we focused on the early phase of migration within the perorally infected birds and mice. Invasion of esophagus by T. regenti cercariae in vitro is not conditioned by secretion of glandular products, including cathepsin B2 of T. regenti (TrCB2). Activity of TrCB2 against mucins, the main components...
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