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Preparation of probes for the cancer imaging based on single photon emission computer tomography (SPECT) based on peptidomimetic inhibitors of FAP protease
Trajhan, Filip ; Konvalinka, Jan (advisor) ; Baszczyňski, Ondřej (referee)
Fibroblast activation protein (FAP) is a membrane serine protease that is mainly expressed in epithelial tumor cells. The specific occurrence in the tumor microenvironment and its absence in most healthy tissues makes this protein an important target for the development of diagnostic probes or targeted endoradiotherapy. The goal of this work is the preparation of a new series of potential probes for SPECT imaging of tumours using low molecular weight FAP inhibitors. The structure and synthetic strategy for four new probes were proposed. At the same time two already published probes serving as references for biodistribution experiments were prepared. Two probes were based on the compound IOCB22-AP446, the most potent FAP inhibitor published so far, which was developed in the laboratory of prof. Konvalinka at the IOCB, Prague. The other four prepared probes used the inhibitor UAMC1110, which is utilized as a targeting molecule in a number of compounds in the clinical testing phase. The degree of FAP inhibition in vitro was determined for all prepared compounds. Furthermore, the ability of the probes to visualise tumour tissue in vivo was tested on two animal models of human tumours. Comparison of the results with published data led to the validation of one of the models for use in further...
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Synthesis and characterization of binding ligands for the study of targeted lysosomal protein degradation
Sidej, Natan ; Konvalinka, Jan (advisor) ; Baszczyňski, Ondřej (referee)
Targeted protein degradation is a novel concept of chemical biology that has been formulated about 20 years ago. Its central postulate is based on the fact that instead of suppressing protein activity with low-molecular inhibitors, we can instead use molecular tools to hijack the host organism's own degradation pathways and force it to degrade chosen proteins by itself. This diploma thesis revolves around the preparation of biocompatible polymeric conjugates called "iBodies" that will be used to induce targeted lysosomal degradation of two model enzymes - Fibroblast activation protein α, and Glutamate carboxypeptidase II. First, a total of four low-molecular ligands were prepared and fully characterized by standard methods of organic synthesis. The first two are mannose-6-phosphonate derivatives that serve as the inducers of protein degradation via the cellular endosomal-lysosomal degradation pathway. The remaining two are known potent inhibitors of the chosen model enzymes that will serve as their targeting-ligands. The prepared compounds were then used to prepare a total of eight poly-N-(2-hydroxypropyl)methacrylamide conjugates called iBodies, after which the polymeric conjugates were fully characterized by standard means of macromolecular chemistry. Afterwards, the obtained conjugates will be...
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Příprava mutantního serpinu z klíštěte \kur{Ixodes ricinus}
EDEROVÁ, Monika
Point mutation altering arginin for tryptophan amino acid residue in P1 site of tick salivary serpin Iripin-1 was created using specific primers. Recombinant protein with this mutation in nucleotide sequence was then expressed in chemically competent Escherichia coli cells, extracted from them and purified by affinity and size-exclusion chromatography. To see the impact of the mutation on inhibitory function of Iripin-1, its ability to bind trypsin and form covalent complexes was evaluated.
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Characteristics and gene expression levels of plant transformants modified by one related constructs shearing a gene for proteinase inhibitor.
BEZUNK, František
Tobacco plants were transformed by bacteria Agrobacterium tumefaciens bearing a plasmid construct with a fusion gene SPI2:GFP and selectable marker NPTII coding for resistance of transformants to antibiotic kanamycin. SPI2:GFP gene was created by a fusion of SPI2- (for serine protease inhibitor) and GFP gene (coding for a green fluorescent protein - GFP) sequences. Transformed tobacco plants were selected on a medium with kanamycin. Positively selected plants were selfed and segregation ratios for NPTII determined for each of genotypes. The presence and function of transgenic DNA was verified by methods of PCR, RT-PCR, Western blot and using the stereomicroscopic fluorescence study of transformants of T0 and T1 generations. This Transgenic genotypes of tobacco Nicotiana tabacum, cv. Petit Havana, SR1 WT showing the expression of the fused gene SPI2:GFP on a level of mRNA and GFP protein were obtained. Thesis was perfomed with a support of the project No. M106030 of Ministry of Education, Youth and Sports of the Czech Republic.
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Study of effects of antiretroviral drugs on transmembrane transport of tenofofovir disoproxil fumarate across MDCKII-ABCB1 cell monolayer
Repeľová, Beáta ; Červený, Lukáš (advisor) ; Čečková, Martina (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Beáta Repeľová Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Study of effects of antiretroviral drugs on transmembrane transport of tenofovir disoproxil fumarate across MDCKII - ABCB1 cell monolayer Tenofovir disoproxil fumarate (TDF) - ester prodrug of tenofovir is considered as one of the most frequently used component of combination antiretroviral therapy. Several ways of application and good patients' tolerability is typical for this compound. TDF is a substrate of dug transporter such as P-glycoprotein (P-gp) therefore its efflux activity may limit the bioavailability after oral administration and distribution of TDF. As many of antiretroviral drugs are also substrates or inhibitors of P-gp, drug - drug interactions with TDF at the level of transmembrane transport could be expected. The aim of the diploma thesis was to describe effects of co-administered antiretroviral drugs on transfer of TDF across MDCKII cell monolayer by using bidirectional transport and concentration equilibrium setups. The results of experiments confirmed that TDF is a substrate of P-gp. High values of efflux ratio describing transmembrane transport of TDF across parental cells have been observed. This...
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Detekce a kvantifikace inhibitorů proteáz v klíštěti \kur{Ixodes ricinus} pomocí monoklonálních protilátek
VANÍČKOVÁ, Martina
Inhibitors of proteases in tick saliva play an important role during tick feeding. Tick saliva contains a wide range of bioactive components which are able to modulate host imunity. Therefore, ticks are able to feed for a long time and transfer tick-borne diseases pathogens. The risk of transfer can be significantly reduced by deactivation of theese protease inhibitors. In this study I made monoclonal antibodies for detection and quantification of two serine protease inhibitors in tick saliva and other tick-body parts.
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Study of effects of antiretroviral drugs on transmembrane transport of tenofofovir disoproxil fumarate across MDCKII-ABCB1 cell monolayer
Repeľová, Beáta ; Červený, Lukáš (advisor) ; Čečková, Martina (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Beáta Repeľová Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Study of effects of antiretroviral drugs on transmembrane transport of tenofovir disoproxil fumarate across MDCKII - ABCB1 cell monolayer Tenofovir disoproxil fumarate (TDF) - ester prodrug of tenofovir is considered as one of the most frequently used component of combination antiretroviral therapy. Several ways of application and good patients' tolerability is typical for this compound. TDF is a substrate of dug transporter such as P-glycoprotein (P-gp) therefore its efflux activity may limit the bioavailability after oral administration and distribution of TDF. As many of antiretroviral drugs are also substrates or inhibitors of P-gp, drug - drug interactions with TDF at the level of transmembrane transport could be expected. The aim of the diploma thesis was to describe effects of co-administered antiretroviral drugs on transfer of TDF across MDCKII cell monolayer by using bidirectional transport and concentration equilibrium setups. The results of experiments confirmed that TDF is a substrate of P-gp. High values of efflux ratio describing transmembrane transport of TDF across parental cells have been observed. This...
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Study of effects of antiretroviral drugs on transmembrane transport of tenofofovir disoproxil fumarate across MDCKII-ABCB1 cell monolayer
Repeľová, Beáta ; Červený, Lukáš (advisor) ; Čečková, Martina (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Beáta Repeľová Supervisor: PharmDr. Lukáš Červený, Ph.D. Title of diploma thesis: Study of effects of antiretroviral drugs on transmembrane transport of tenofovir disoproxil fumarate across MDCKII - ABCB1 cell monolayer Tenofovir disoproxil fumarate (TDF) - ester prodrug of tenofovir is considered as one of the most frequently used component of combination antiretroviral therapy. Several ways of application and good patients' tolerability is typical for this compound. TDF is a substrate of dug transporter such as P-glycoprotein (P-gp) therefore its efflux activity may limit the bioavailability after oral administration and distribution of TDF. As many of antiretroviral drugs are also substrates or inhibitors of P-gp, drug - drug interactions with TDF at the level of transmembrane transport could be expected. The aim of the diploma thesis was to describe effects of co-administered antiretroviral drugs on transfer of TDF across MDCKII cell monolayer by using bidirectional transport and concentration equilibrium setups. The results of experiments confirmed that TDF is a substrate of P-gp. High values of efflux ratio describing transmembrane transport of TDF across parental cells have been observed. This...
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Secreted proteases of the liver fluke and their interaction with endogenous inhibitor
Buša, Michal ; Konvalinka, Jan (advisor) ; Ryšlavá, Helena (referee)
The liver fluke, Fasciola hepatica, is one of the most important parasites of livestock, and it also infects humans. The proteolytic system of trematodes is critical for their interaction with the host and is a potential target for the development of novel vaccines. This work is focused on proteases secreted by F. hepatica adults and on FheCy2, a new protease inhibitor from the cystatin family. The proteolytic activity of the secreted proteases was analyzed using: (a) chromogenic protein substrates and fluorogenic peptide substrates, (b) selective protease inhibitors, and (c) a fluorescent activity-based probe for visualization of proteases. The results showed that the secreted proteases are cysteine proteases of papain family belonging to cathepsins L and B. These proteases were effectivelly inhibited by FheCy2 as demonstrated by enzymological analysis. It can be assumed that FheCy2 participates in the physiological regulation of endogenous proteases secreted by F. hepatica adults, which makes it attractive candidate protein for vaccination studies. Key words: Fasciola hepatica, cathepsins, proteolytic activity, substrate specificity, protease inhibitors (In Czech)
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