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The role of γc cytokines in the immune system and cancer immunotherapy
Ptáček, Bohumil ; Kovář, Marek (advisor) ; Adkins, Irena (referee)
Cytokines are proteins produced mostly by cells of hematopoietic origin and transduce signals via engaging cell surface receptors on either the cytokine-producing cells (autocrine signaling) or other target cells (paracrine signaling). Common cytokine receptor subunit (γc) cytokines are small glycoproteins belonging to type I cytokines with pleiotropic activities in both the innate and adaptive immune systems. All γc cytokines share a γc receptor subunit in their complete receptors. The first part of this thesis aims to summarize information about the biology of γc cytokines, their receptors, and their role in the immune system and its functions. The second part discusses the use of γc cytokines in cancer immunotherapy, presenting examples of particular γc cytokine therapies, and describes the approaches to improve the pharmacological features of γc cytokines or efficiently combine them with other immunotherapies and anticancer treatments. Keywords: γc cytokine, cytokine receptor, T cell, NK cell, cancer immunotherapy
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Exprese CD47 a jeho topologie na povrchu primárních buněk karcinomu močového měchýře při interakci s makrofágy
Rajtmajerová, Marie ; Drbal, Karel (advisor) ; Brdička, Tomáš (referee)
CD47 is a so-called "don't eat me" signal, which protects cells from phagocytosis. Its high expresion on tumor cells brings new perspective to the tumor therapy. Monoclonal antibodies, which are these days undergoing clinical trials, prevent CD47 binding to the SIRPA inhibitory receptor on macrophages, and so they enhance their phagocytic functional capacity. In this way they enable phagocytic removal of tumor cells. Overall expression, structural conformation and stoichiometry of CD47 on a particular cell predestine whether it will be phagocytised. The aim of the thesis is to develop and test methods to characterise expression parameters of CD47 via flow cytometry (FCM), quantitative PCR (qPCR) and microscopy. To achieve this goal I performed competition tests of commercially available antibodies in order to characterise their binding epitopes on cell lines. After performing tSNE analysis of primary BCa patient samples I correlated CD47 expression with other cell surface markers. I focused on CD47 expression in various differentiation stages of the tumor. To better understand the relationship between CD47 expression and differentiation status of cells I performed qPCR analysis of particular transcription factors. Using cell lines I examined method for phagocytosis quantification, which will be...
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Indoleamine 2,3-dioxygenase 1 inhibitors in cancer immunotherapy
Muffová, Barbora ; Poláková, Ingrid (advisor) ; Šroller, Vojtěch (referee)
The indoleamine 2,3-dioxygenase (IDO 1) enzyme is expressed in small amounts in most of the mammalian tissues, and its production is detected also in various types of tumours. IDO 1 catalyses the very first step of the kynurenine pathway, the tryptophan conversion to N-formylkynurenine, which is further metabolized to kynurenine (Kyn). The kynurenine/ tryptophan ratio (kyn/trp) may be used as a prognostic marker in research and treatment of IDO 1+ tumours. The kyn/trp demonstrates the activity of IDO 1 in tumours. The goal of cancer immunotherapy based on IDO 1 inhibition is to reverse or reduce the protumour effects of IDO 1, such as avoiding NK and T cells inhibition and activation of regulatory T cells or association with tumour-associated macrophages (TAM). IDO 1 inhibitors have been examined alone in monotherapy or together with cytotoxic T-lymphocytes antigen 4 (CTLA-4) inhibitors and programmed cell death protein 1 (PD-1) inhibitors in combined therapy. Recently, several studies are dedicated to invent inhibitors, which are able to inhibit the activity of other trp-catalysing enzymes, the indoleamine 2,3-dioxygenase 2 (IDO 2) and tryptophan 2,3-dioxygenase (TDO), together with the IDO 1 activity. Cancer immunotherapy based on IDO 1 inhibition may be combined also with chemotherapy.
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Antitumor activity of IL-2 and IL-7 immunocomplexes in combination with αCTLA-4 and αPD-1 mAbs
Hnízdilová, Tereza ; Kovář, Marek (advisor) ; Hájková, Michaela (referee)
Biological activity of IL-2 and IL-7 in vivo is significantly increased when complexed with some of the respective anti-cytokine mAb. Different immune cell subsets can be preferentially stimulated depending on the anti-IL-2 mAb used to complex IL-2. IL-2/anti-IL-2 mAb S4B6 immunocomplexes (IL-2/S4B6) induce preferential expansion of CD122high cells whereas IL-2/anti-IL-2 mAb JES6-1 immunocomplexes (IL-2/JES6-1) highly selectively stimulate CD25high cells in mice. Similarly, IL-7/anti-IL-7 mAb M25 immunocomplexes (IL-7/M25) possess higher stimulatory activity for both naïve and memory CD8+ T cells in vivo in comparison to free IL-7. CTLA-4 and PD-1 molecules are inhibitory receptors which negatively regulate proliferation, survival and effector functions of T cells. Blocking antibodies against these molecules represent promising immunotherapeutic tool for treatment of malignant diseases. We examined possible synergism of IL-2/S4B6 and αCTLA-4 plus αPD-1 mAbs in tumor-bearing mice. We found that the expansion of recently activated CD8+ T cells driven by IL-2/S4B6 was further augmented by αCTLA-4 plus αPD-1 mAbs. However, these two immunotherapeutic approaches did not show synergistic antitumor activity in any mouse tumor model tested. Next, we showed that IL-7/M25 possessed higher biological activity...
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Factors affecting the efficacy of anti-tumor therapy by blocking the PD-1/PD-L1 signaling pathway and predictive biomarkers of this treatment
Majerová, Miriam ; Šmahel, Michal (advisor) ; Krulová, Magdaléna (referee)
In recent years there has been a focus on cancer therapies that use patient's immune system instead of invasive traditional methods. One such method of immunotherapy is using checkpoint inhibitors. Blockade of PD-1/PD-L1 signaling pathway is one of main immunotherapy approaches utilizing patient's immune cells to combat cancer cells. Despite of positives that come along with this blockade, many patients do not respond to treatment. Therefore, better understanding of immune mechanisms and factors that affect the efficacy is needed. Finding and summarizing predictive biomarkers play an important role in selection of patients with highest chances of positive outcome and it could result in higher percentage of positively responding patients. It could also prevent patients from experiencing adverse events and unnecessary discomfort. Key words: immune checkpoints, immunotherapy, inhibitors, PD-1, PD-L1, biomarkers
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Anti-CD47 protilátka v nádorové terapii
LENCOVÁ, Radka
The aim of this thesis was to answer question whether it is possible to improve the effect of cancer immunotherapy. This is based on the combination of TLR agonists and the ligands stimulating phagocytosis. We used anti-CD47 antibody to block CD47 on tumor cells. The second question was whether it is practicable to reduce the number of vaccine applications.
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Exprese CD47 a jeho topologie na povrchu primárních buněk karcinomu močového měchýře při interakci s makrofágy
Rajtmajerová, Marie ; Drbal, Karel (advisor) ; Brdička, Tomáš (referee)
CD47 is a so-called "don't eat me" signal, which protects cells from phagocytosis. Its high expresion on tumor cells brings new perspective to the tumor therapy. Monoclonal antibodies, which are these days undergoing clinical trials, prevent CD47 binding to the SIRPA inhibitory receptor on macrophages, and so they enhance their phagocytic functional capacity. In this way they enable phagocytic removal of tumor cells. Overall expression, structural conformation and stoichiometry of CD47 on a particular cell predestine whether it will be phagocytised. The aim of the thesis is to develop and test methods to characterise expression parameters of CD47 via flow cytometry (FCM), quantitative PCR (qPCR) and microscopy. To achieve this goal I performed competition tests of commercially available antibodies in order to characterise their binding epitopes on cell lines. After performing tSNE analysis of primary BCa patient samples I correlated CD47 expression with other cell surface markers. I focused on CD47 expression in various differentiation stages of the tumor. To better understand the relationship between CD47 expression and differentiation status of cells I performed qPCR analysis of particular transcription factors. Using cell lines I examined method for phagocytosis quantification, which will be...
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