|
|
Transmission and epidemiology of visceral leishmaniasis
Spitzová, Tatiana ; Volf, Petr (advisor) ; Antoniou, Maria (referee) ; Dujardin, Jean-Claude (referee)
Visceral leishmaniasis (VL) is widespread disease caused by protozoa Leishmania donovani and Leishmania infantum. Human visceral leishmaniasis caused by Le. donovani in India is considered an anthroponosis, however in East Africa, the role of animals as reservoirs remains unclear. The first part of this thesis demonstrated natural Leishmania infection in wild rodents and bats in Ethiopia. Overall, 8.2% rodents and 4.9% bats were positive for Leishmania spp. Subsequent sequencing revealed that 10% of Leishmania-positive rodents were infected by parasites from Le. donovani complex, on the other hand, no Le. donovani DNA was detected in bats. All Le. donovani-positive rodents were captured in the localities of southwest Ethiopia where human VL cases have been reported and potential sand fly vectors occur. Our findings indicate that rodents are likely to play a role in VL transmission in Ethiopia. During blood feeding, sand flies inoculate into the host skin immunogenic salivary proteins which elicit species specific antibody response. Anti-saliva antibodies could be used as a marker of host exposure to sand flies and, in leishmaniasis endemic areas, also as risk markers of Leishmania infection. In order to find out if the domestic animals (dog, goat, cow, and donkey) from north and northwest Ethiopia...
|
|
|
Transmission and epidemiology of visceral leishmaniasis
Spitzová, Tatiana
Visceral leishmaniasis (VL) is widespread disease caused by protozoa Leishmania donovani and Leishmania infantum. Human visceral leishmaniasis caused by Le. donovani in India is considered an anthroponosis, however in East Africa, the role of animals as reservoirs remains unclear. The first part of this thesis demonstrated natural Leishmania infection in wild rodents and bats in Ethiopia. Overall, 8.2% rodents and 4.9% bats were positive for Leishmania spp. Subsequent sequencing revealed that 10% of Leishmania-positive rodents were infected by parasites from Le. donovani complex, on the other hand, no Le. donovani DNA was detected in bats. All Le. donovani-positive rodents were captured in the localities of southwest Ethiopia where human VL cases have been reported and potential sand fly vectors occur. Our findings indicate that rodents are likely to play a role in VL transmission in Ethiopia. During blood feeding, sand flies inoculate into the host skin immunogenic salivary proteins which elicit species specific antibody response. Anti-saliva antibodies could be used as a marker of host exposure to sand flies and, in leishmaniasis endemic areas, also as risk markers of Leishmania infection. In order to find out if the domestic animals (dog, goat, cow, and donkey) from north and northwest Ethiopia...
|
|
|
Antigens in the sandfly saliva and antibody response of the bitten hosts
Drahota, Jan ; Volf, Petr (advisor) ; Kopecký, Jan (referee) ; Soares Maia, Carla Alexandra (referee)
Leishmaniases are neglected diseases occurring mainly in developing countries of Africa, Asia and Latin America. However, these diseases are also present in Europe and North America and due to climate changes and human activities they spread to higher latitudes and altitudes. In these theses, we review the current information about the spread of leishmaniases, its vectors and reservoirs in Europe. The risk of Leishmania transmission is closely connected with the host-vector contact. Recently, immunoglobulin G (IgG) antibody response to sandfly saliva has been proven as a reliable marker of the host exposure. However, sandfly saliva is a complex mixture of components with different chemical and antigenic properties and it is laborious and expensive to acquire. Therefore, we have focused on preparation of major salivary antigens in the form of recombinant proteins that would be capable to replace the saliva in immunological screenings. We choose two European vectors, Phlebotomus (P.) papatasi and Phlebotomus (P.) perniciosus and identified their major salivary antigens by western blotting and mass spectrometry. We expressed these proteins in the bacterial system and test their antigenicity using ELISA and western blotting with sera of mice and dogs bitten by these sand fly species. The most promising...
|
|
| |
|
| |
|
|
Phlebotomine saliva: the perspecives of application of some of their recombinantly produced proteins
Rožníčková, Lucie ; Zídková, Lenka (advisor) ; Štáfková, Jitka (referee)
Sandflies (Diptera: Phlebotominae) are the vectors of one of the most significant tropical diseases, leishmaniosis. Their saliva contains substances with antihemostatic, vasodilatory and immunomodulatory effect. These substances are of great significance in transmission of leishmaniosis, because of their ability to influence the host immune response. Naive host saliva modulate the immune system to such an extent, that it reduces an infective dose and increases the pathogenicity of leishmaniosis. On the other hand, a repeatedly exposed host generates a cellular and antibody immune response, which is able to make the initial development of infection impossible. Repeated exposure of individual sandflies lead to formation of antibodies against components of saliva, which may play a role as a rate exposure indicator and thus the risk of leashmaniosis infection. These proteins and glycoproteins can be produced by recombinant DNA technology. Recombinant vaccine could help in the fight against leishmaniasis. Keywords: saliva, sand fly, leishmania, recombinant proteins.
|
|
|
Study of receptor-ligand pair NKR-P1F and Clrg
Kotýnková, Kristýna ; Man, Petr (advisor) ; Schneider, Bohdan (referee)
Study of receptor-ligand pair NKR-P1F and Clrg Mouse NKR-P1F:Clr-g receptor:ligand pair is important component of the receptor "zipper" that occurs at the contact between natural killer cell and its target cell, and represents a recently discovered example of lectin-lectin interactions important for recognition among immune cell subsets. In order to study structure of these proteins and interactions between them, we have prepared pET-30a(+) bacterial expression vectors coding parts of extracellular domains of the two receptors. After induction of protein production with IPTG, the proteins precipitated into inclusion bodies, from which they could be refolded in vitro. Refolded proteins were purified using combination of ion exchange and size exclusion chromatography. NKR-P1F construct yielded only small amounts of soluble protein using standard refolding protocols. Furthermore we have experienced difficulties with reproducibility of the refolding results. In the case of Clrg the standard protocols for protein refolding were not sufficient. In order for the Clrg to fold properly, the odd cysteine which does not fit into the pattern usual for this family of receptors was substituted for serine and resulting C148S construct was shown to be more useful. Further, using (benzyldimethylammonio)propanesulfonate in...
|
|
|
Studies of NK cell receptors and other proteins using recombinant expression and mass spectrometry
Kavan, Daniel ; Bezouška, Karel (advisor) ; Tučková, Ludmila (referee) ; Řehulka, Pavel (referee)
Charles University in Prague Faculty of Science Department of Biochemistry Studies of NK cell receptors and other proteins using recombinant expressions and mass spectrometry Summary of Ph. D. Thesis Daniel Kavan Supervisor: Prof. RNDr. Karel Bezouška, DSc. Prague 2010 Daniel Kavan Introduction Introduction NK cells and CD69 as one of their surface receptors Natural killer cells (NK cells) are the subpopulation of large granular lymfocytes, which lacks the surface receptors typical for B cells or T cells. They are characterized by the presence of NKp46 and NKp30 [Moretta L. et. al. 2002], however. They were named natural killers according to their function in the organism, as they do not need any activation and nevertheless they are able to eliminate abnormal (i. e. infected or transformed) cells from the tissue [Kiessling R. et. al. 1975]. This function is dependent on scanning the major histocompatibility complex (MHC) class I molecules of ambient cells. The resulting action (killing or not killing the target cell) is dependent on the balance of activating and inhibiting signals mediated by the NK cell surface receptors and forwarded to the specific signaling pathway [Raulet D. H. et. al. 2001]. Specificity of NK cells is not based only on one type of antigen receptor as it is in case of T and B cells,...
|
|
|
Preparation and characterization of human cellular cofactors of retroviral integration.
Čermáková, Kateřina ; Maloy Řezáčová, Pavlína (advisor) ; Obšil, Tomáš (referee)
Lens epithelium-derived growth factor/p75 (LEDGF/p75) is a prominent cellular binding partner of Human Immunodeficiency Virus type 1 (HIV-1) integrase. It is a human nuclear protein, which has been implicated in transcriptional regulation and cell survival. The role of LEDGF/p75 in HIV integration is well characterized, the HIV integrase binding domain (IBD) was identified and structural studies, which provide detail information about this interaction, were done. However, very little is known about its physiological function. As a transcriptional co-activator, LEDGF/p75 is implicated not only in HIV replication, but also in human cancer and autoimmunity. Key feature for both, the viral and cellular role of this protein, is its ability to act as a molecular adaptor tethering proteins to the chromatin fiber. Recently, PogZ (Pogo transposable element derived protein with zinc finger domain) was identified and validated as a new cellular interaction partner of LEDGF/p75. It was shown, that their interaction is mediated by IBD of LEDGF/p75 and the C-terminal domain of PogZ. To gain more insight in this interaction, we have initiated structural studies of their complex. Structural information is crucial for understanding the LEDGF/p75 biological role and might help in design of inhibitors selectively blocking...
|
|
| |
guest ::
