Thesis (M.S.)--Brigham Young University. Dept. of Microbiology and Molecular Biology, 2007. / Includes bibliographical references (p. 37-40).

Gene therapy is the introduction or alteration of genetic material with the intention to treat disease. To support this aim, viruses have been modified, with elements linked to viral pathogenicity removed from their genome and replaced by the genetic material to be delivered. Gene therapy vectors based on lentiviruses have many advantages, such as the ability to transduce non-dividing cells and to target specific cell types via pseudotyping. They have been successfully used in ex vivo clinical trials for several haematopoietic stem cell disorders. Lentiviral vectors, however, suffer from substantially lower titres than the more popular adeno-associated virus (AAV)-based vectors and therefore have limited applicability for in vivo gene therapy which requires much greater quantities of virus. The main aim of this thesis was to investigate strategies to improve lentiviral vector productivity during manufacture, in order to increase the likelihood of lentiviruses being adopted for disease treatment. Initial experiments were based on the lentiviral vector manufacturing process currently being developed by the United Kingdom Cystic Fibrosis Gene Therapy Consortium for the generation of highly concentrated, purified lentivirus for clinical use. Supplementation of FreeStyle 293 Expression Medium used during upstream processing was attempted, but none of the assessed supplements led to significant increases in lentiviral vector production. Investigation into intrinsic immunity to viral infection indicated that over-expression of the protein kinase RNA-activated (PKR) led to lower production titres, but over-expression of its inhibitors was not successful at increasing titres. The focus then shifted to reducing, or 'knocking-down', inhibitory factors present in the host cells, which could adversely affect viral titres. Investigation of the published HIV-1 literature revealed a possible 152 candidate inhibitory factors described as having a negative impact on HIV-1 replication in the late stages of the life cycle of the virus. A novel siRNA screen was developed to assess the effect of ‘knock-down' of inhibitory factors on lentiviral vector titre. Application of the screen to 89 candidate inhibitory factors identified nine genes which, when knocked-down, resulted in increased lentiviral vector production by more than 40%. Further work will be necessary to understand the role of the inhibitory factors in lentiviral vector production, but novel cell lines in which genes encoding these factors have been permanently deleted from producer cells could lead to higher titres, reducing costs in the manufacture of lentiviral vectors and making in vivo gene therapy more feasible from a health economics perspective.

Orientadores: Clarice Weis Arns, Dagmar Ruth Stach-Machado / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-11T14:40:18Z (GMT). No. of bitstreams: 1 Coswig_LiaTreptow_D.pdf: 19863975 bytes, checksum: 7e0e923baa4947ed3f77ff3ca34747e9 (MD5) Previous issue date: 2008 / Resumo: o Metapneumovírus Aviário (AMPV), também denominado vírus da rinotraqueíte dos perus (TRT), é um vírus que acomete e causa infecção no trato aéreo superior das galinhas e perus. Além da infecção respiratória, em poedeiras e matrizes está associado com uma queda significativa na produção de ovos. Em galinhas o vírus está relacionado com a Síndrome da Cabeça Inchada (SCI), uma enfermidade multifatorial, e por este motivo é importante o diagnóstico diferencial. Testes realizados com anticorpos monoclonais (Mabs) e técnicas moleculares são capazes de detectar diferenças entre os subtipos do vírus. Os métodos de diagnóstico incluem isolamento ou detecção da partícula viral ou testes sorológicos. O isolamento das amostras virais SHS-BR-121 (subtipo A) e STG-SHS-1439 (subtipo B) foi realizado em cultura de anel de traquéia, em fibroblasto de embrião de galinha (FEG) e em células chicken embryo related (CER). A comparação das médias dos títulos obtidos para as duas amostras virais, em célula CER, apresentou diferença estatisticamente significativa (P=0,014) com p< 0,05. Neste projeto foi avaliada a suscetibilidades de seis sistemas celulares (CER, Vero, BHK-21, HEp-2, MDBK e ED) para a multiplicação das duas amostras virais (subtipos A e B). Destes sistemas as células CER, Vero e BHK-21 demonstraram ser apropriadas para a replicação vira!. Os títulos nestas células variaram de 105.5 a 107,o/mL DICC50 , para o vírus SHS-BR-121, e 105,5 a 106.0/mL DICC50 para o vírus STG-SHS-1439. As diferenças entre as médias dos títulos nos diferentes sistemas celulares foi estatisticamente significativa para a amostra SHS-BR-121 inoculada em CER em relação as células Vero e BHK-21 (P= 0,01 e P=0,004, respectivamente) com p< 0,05. Para a amostra STG-SHS-1439 não houve diferença estatística significativa, com p<0,05. A curva da cinética viral foi realizada para as duas amostras virais, em três sistemas celulares, CER, Vero e BHK-21, demonstrando estas diferenças. Foram produzidos anticorpos monoclonais contra o AMPV isolado no Brasil, sendo obtidos cinco anticorpos monoclonais para o antígeno viral através da fusão celular que apresentaram os isotipos IgG1, IgG2a e IgG2b quando da isotipagem. Dos cinco anticorpos monoclonais, três possuíam atividade neutralizante e quatro deles inibiram a fusão invitro. No teste de soroneutralização cruzada foram utilizadas três amostras virais para a análise, sendo elas SHS-Br-121, STG 854/88 e TRT-SHS-1439. Todos os anticorpos monoclonais apresentaram resultado positivo em relação à amostra homóloga, sendo que três apresentaram resultados positivos também para as amostras heterólogas. Os resultados confirmam que os dois anticorpos monoclonais descritos podem ser utilizados com importante ferramenta nos estudos epizootiológicos e para o diagnóstico específico dos subtipos na infecção pelo Metapneumovírus Aviário / Abstract: Avian Metapneumovirus (AM PV) , also denominated virus of the rhinotracheitis of the turkeys, it is a virus that attacks and it causes infection in the upper respirator) tract of chickens and turkeys. Besides the respiratory infection, in breeders and layers is associated with a significant fall in the production of eggs. In chickens the virus is related with the Swollen Head Syndrome (SHS), an illness multifactorial and for this reason it is very important the differential diagnosis. Tests accomplished with monoclonal antibodies (Mabs) and molecular techniques are capable to detect differences among the subtypes of the virus. Methods for the diagnosis of AMPV infections include detection or isolation of the virus itself, demonstration of a specific antibody response to the virus. For the primary isolation of the two samples of AMPV SHS-BR-121 (subtype A) and STG-SHS-1439 (subtype B) was it accomplished ir chicken embryo tracheal" organ culture (TOC), in chicken embryo fibroblast cell culture (CEF) and was it accomplished in cell line chicken embryo related (CER). Done the comparison of the averages of the titers obtain for the two strains, in cellline CER, did present statistically significant difference (P=0,014) with p< 0,05. The growth of SHS121-BR and STG-SHS-1439 was evaluated in six different celllines (CER, Vero, BHK21, HEp-2, MDBK and ED). CER, Vero and BHK-21 showed to be the most appropriate for virus multiplication. The titers in these cells varied from 105.5 to 107,o/mL !CID50, for the virus SHS-BR-121, and 105,5 to 106,o/mL TCID50 for the virus STG-SHS71439. The differences among the averages of the titers in the different cell lines was statistically significant differences (P=0,01) with p<0,05 for the strain SHS-BR-121 in CER cellline. One-step growth curves of the strains SHS-BR-121 and STG-SHS-1439 in CER, Vero and BHK-21 showed that there was not statistically significant difference in the infectious virus titers from 0 to 60 hours after infection. Five monoclonal antibodies were obtained for the viral antigen through the cell fusion that showed the isotypes IgG1, IgG2a and IgG2b, when of the characterization of Mabs. Three of them showed neutralizing activity and four inhibited the fusion in vitro. These MAbs were used to investigate antigenic relationship among three strains (SHS-BR-121, STG 854/8o/and TRT1439/91) of a MPV subtypes A and B using cross-neutralization test. When the five hybridomas were analyzed showed result positive for the homologus virus. In relation t4 two samples of heterologus AMPV three Mabs were positive to heterologus AMPV. Th4 results confirm that the two monoclonal antibodies described can be used as a valuable tool in the epizootiological and serological studies, and also for the specific diagnosis o the subtypes in the infection for Avian Metapneumovirus / Doutorado / Microbiologia / Doutor em Genetica e Biologia Molecular

Chronic lymphocytic leukemia (CLL) cells are considered to be derived from antigen-exposed B cells. To further explore the antigen-driven selection behind the leukemogenesis of CLL, we performed immunoglobulin (Ig) specificity screening of 7 CLL cell lines and 23 primary CLL clones from patient peripheral blood. We also included a recombinant monovalent monoclonal antibody (mAb) belonging to a subset of CLL cases with identical or semiidentical heavy chain complementarity determining region 3 (HCDR3) of the IGHV3-21 gene rearrangement. We found CLL mAb specificities against vimentin, filamin B, cofilin-1, proline-rich acidic protein 1, cardiolipin, oxidized low density lipoprotein and Streptococcus pneumoniae polysaccarides. These molecules are functionally associated with microbial infection and/or apoptotic cell removal. An antigen-driven selection would therefore imply that CLL B cell precursors are involved in the elimination and scavenging of pathogens and apoptotic cells, which could trigger the development of the disease. The limited in vitro survival of CLL cells makes Epstein-Barr virus (EBV) immortalization of CLL cells a useful experimental model for studies on antibody-specificity screening. Considering the intricate procedure of EBV transformation of CLL cells and the many false cell lines used worldwide, we also wanted to characterize and evaluate the authentic origin of several previously established CLL cell lines and their normal lymphoblastoid counterparts. Three of the CLL cell lines tested were truly authentic (I83-E95, CLL-HG3 and CII), two had features of a biclonal Ig expression (232B4 and WaC3CD5+), one was only tentatively verified (PGA-1), whereas one cell line could not be verified (EHEB) due to lack of original patient cells for comparison. Two of the presumed normal lymphoblastoid cell lines tested were shown to be a neoplastic CLL clone. This study emphasizes the importance of proper cell line authentication and we will continue to verify additional cell lines not yet proven authentic. In conclusion, we provide evidence for natural Ab production by CLL cells and suggest that these cells might be derived from B cell precursors involved in the innate immunity and, thus, providing a first-line-defence against pathogens and in elimination of apoptotic cells.

An approach to investigating cancer that has recently seen resurgence of interest is the “Warburg effect”. Otto Warburg originally described the altered metabolism of cancer cells and identified that they exhibit an increase in glucose uptake and lactate production. This up-regulation of glycolytic flux and glucose transport is now associated with 90% of cancers. In order to improve the overall understanding of the “Warburg effect” two forms of systems biology have been implemented - comparative in vitro analysis of kinetic activities and dynamic modelling. In this analysis, human breast cancer cell lines MCF-7, MDA-MB-231 and T47D and a non transformed breast cell line MCF-10A were used to identify key similarities and differences in kinetic activities across the glycolytic pathway. Additionally, activities of key glycolytic enzymes hexokinase, pyruvate kinase and lactate dehydrogenase were compared under hypoxic conditions to further understand regulation of cancer cells. The most prominent feature that arose from comparing the kinetic activities of the three malignant and one non-malignant cell line is that each cell line has its own specific set of activities for glycolysis. This indicates that there are differences in regulation across the glycolytic pathway for each of these cell lines. This is of specific interest in the search for therapeutic targets. Further, we determined that despite the prominence of oncogenic HIF signalling activities of hexokinase, pyruvate kinase and lactate dehydrogenase were further modulated by growth under hypoxic conditions. Despite the lack of obvious distinct kinetic differences between the non-cancerous and cancerous cells lines some discernible differences are apparent when modelled in silico.

Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology and Toxicology Student: Kateřina Kafuňková Supervisor: RNDr. Jana Maixnerová, Ph.D. Title of diploma thesis: Evaluation of liver toxicity in vitro The subject of the diploma thesis is toxicity evaluation of newly synthesised substances on a cellular model representing a hepatocyte. The tested substances have been provided by the Department of Organic and Bioorganic Chemistry at the Faculty of Pharmacy in Hradec Králové, Charles University, as potential antifungal pharmaceuticals and medicine effective against Methicillin-resistant Staphylococcus aureus (MK-NO2-1, MK-NO2-2, DAB-5-K, PABA-Me-5, PABA-Et-5, MK-F-1, PABAN- 3, PABAN-5, MK-F-2, MK-CF3-1, MK-CF3- 2). In order to determine the toxicity we have implemented two methods. The first method is based upon measuring metabolic activity of cells by means of reducing tetrazolium to a colored product. The second method detects the amount of LDH released as a marker of toxicity. The human hepatoma cell line HepG2was used as a model. . The IC50 and EC50 parameters were used to assess the degree of viability and cytotoxicity. The final values obtained from the first method indicated all tested substances showed a certain level of toxicity to the hepatic tissue. MK-CF3-2 is the most...

The application of nanoparticles in the field of theranostics requires knowledge of the specific interaction of nanoparticles with the immune system. One of the first cells with which nanoparticles interact when given to the body are cells of the mononuclear phagocytic system. The aim of this diploma thesis is to prepare an in vitro study that describes the effect of two types of gold and three types of silicon ultra-small nanoparticles on immune cells. Immune cells are presented in the form of primary PBMCs isolated from whole blood , and cells of monocytic cell line THP-1 in the form of monocytes and differentiated macrophages. During the experiments with primary cells, emphasis is placed on maintaining the concept of personalized protein corona. After characterization of the immune cells used, cells are subsequently stimulated with ultra-small nanoparticles and the influence of these nanoparticles on cell metabolism, viability, degree of differentiation and secretion of pro- and antiinflammatory cytokines is monitored. The outcome takes into account further use of the tested nanoparticles in the field of biomedicine. Key words: primary monocytes, cell lines, differentiation, macrophages, cytokines, cytotoxicity

Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Lucie Čermáková Supervisor: RNDr. Eva Novotná, Ph.D. Title of diploma thesis: The effect of acalabrutinib and ibrutinib on the efficacy of daunorubicin in cancer cells Leukemia presents malignant diseases of hematopoiesis, which essence is the malignant transformation of a hematopoietic stem cell at various levels of maturation and increased proliferative activity. Chemotherapy is the gold standard in the treatment of leukemia. One of the many treatments is the use of anthracycline chemotherapeutics, especially daunorubicin (DAU). Anthracyclines are widely used in clinical practice but have high cardiotoxic effects that limit their dosage. One of the main causes of side effects is the reduction of an anthracycline chemotherapeutic to the appropriate toxic metabolite, which accumulates in the heart. Carbonyl, reducing enzymes from the superfamily aldo-ketoreductase (AKR), and short-chain dehydrogenase/reductase (SDR) are involved in this reduction. At the same time, carbonyl reducing enzymes, has been shown to be involved in the mechanisms that cause tumor cells to be resistant to anthracyclines, thereby reducing the inhibition of the growth of these cells. In the diploma thesis we found that...

In the search for new genes that are regulated by thyroid hormone, DISP3, a new member of the SSD (sterol-sensing domain) protein family, has been identified. Expression analysis showed that DISP3 is expressed in cells of neural origin, and our previous results indicate that overexpression of this gene affects cell proliferation and differentiation. Oncomine database analysis also showed that DISP3 expression is increased in medulloblastomas, the most common malignancies of the central nervous system in children. The subject of this diploma thesis is studying the effect of increased DISP3 levels on cell apoptosis and cell ability to form a colony. Cell lines derived from medulloblastomas were used in the work. We compared the expression levels of the DISP3 gene in different medulloblastoma lines by quantitative PCR and selected a line with low expression of this gene for further experiments. Some medulloblastoma cell lines can form neurospheres when cultured in serum-free medium. Using quantitative PCR, we compared the expression levels of neural markers in cells cultured both as neurospheres and as adherent cells. By transfecting cells with a plasmid overexpressing DISP3, we prepared cells with increased levels of this gene. We induced apoptosis by radiation at different doses. Apoptosis was...

Magister Scientiae (Medical Bioscience) - MSc(MBS) / Insect-derived baculoviruses have been used extensively as a safe and versatile research model for transgenic protein expression. Preclinical studies have revealed the promising potential of Baculoviruses as a delivery vector for a variety of therapeutic applications, including vaccination, tissue engineering and cancer treatments. Coronaviruses are enveloped viruses containing linear, non-segmented ribonucleic acid. Human coronavirus NL63 was first discovered in the Netherlands in January 2004, where a 7-month-old girl presented with an acute respiratory tract infection that was later established to predominantly infect infants, the elderly and immunocompromised individuals.