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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The interaction of genetic and environmental vascular risk markers in patients with non-insulin-dependent diabetes mellitus and their first degree relatives

Mansfield, Michael William January 1997 (has links)
No description available.
2

Clonagem e expressão do fator VII de coagulação sanguínea em linhagens celulares humanas / Cloning and expression of coagulation factor VII in human cell lines

Freitas, Marcela Cristina Corrêa de 29 May 2015 (has links)
O Fator VII recombinante (FVIIr) tem sido a principal escolha terapêutica dos pacientes hemofílicos que desenvolvem inibidores contra os fatores VIII e IX utilizados como tratamento. Atualmente, o produto utilizado é produzido em células de camundongo (BHK-21), o qual oferece desvantagens considerando a complexidade das modificações pós-traducionais desta proteína e a inserção de glicosilações de origem murina altamente imunogênicas aos seres humanos. Dessa maneira a produção de proteínas para uso terapêutico em linhagens celulares humanas surge como uma alternativa promissora. Dentro desse contexto, o objetivo principal deste trabalho foi clonar e expressar o FVII de coagulação sanguínea em 3 linhagens celulares humanas (HepG2, Sk-Hep, HKB-11), compará-las com a linhagem murina BKH-21, e selecionar a melhor produtora da proteína recombinante. As células foram modificadas com o vetor lentiviral p1054-CIGWS, contendo os genes do FVII e do marcador GFP. Após a modificação das células foi observada uma eficiência de transdução de 80% nas células BHK-21-FVIIr, 73% nas células HepG2-FVIIr, 32% nas células HKB-11-FVIIr e 95% Sk-Hep-FVIIr. Análises da expressão gênica por PCR em Tempo Real mostraram que as três linhagens humanas modificadas apresentaram expressão do RNAm relativo ao FVIIr, sendo que a linhagem celular HepG2 foi a que teve maior expressão de FVIIr, seguida da Sk-Hep-1 e HKB-11. Quando submetidas ao tratamento com vitamina K por um período de 10 dias em cultura, a expressão do gene FVIIr foi semelhante para as três linhagens (HepG2: 164563 URE, HKB-11: 119122 URE e Sk-Hep: 124919 URE). O FVII é uma proteína que para sua ativação, possui como principal modificação pós traducional a -carboxilação vitamina K dependente, que ocorre por meio do ciclo da vitamina K com a participação de 3 enzimas, -carboxilase, VKORC1 e calumenina (inibidor). A expressão gênica dessas enzimas foi avaliada antes e após o tratamento com a vitamina K. Foi possível observar que houve um aumento nos níveis de RNAm nas células humanas tratadas com vitamina K, sugerindo que esta é capaz de ativar as enzimas do ciclo da -carboxilação. A cinética de crescimento celular em garrafas estáticas mostrou que a as células murinas BHK-21 modificadas possuem uma velocidade específica de crescimento 25% mais elevada que das células humanas. Contudo a cinética de produção das linhagens recombinantes mostrou que as células humanas produzem cerca de 3 vezes mais FVIIr do as células BHK-21. Devida a baixa produção de FVIIr na linhagem celular murina, e ao fato de que a linhagem humana HepG2 apresenta um perfil de crescimento extremamente lento, as linhagens recombinantes Sk-Hep-1-FVIIr e HKB-11-FVIIr foram selecionadas para ensaios de cultivo em suspensão utilizando microcarregadores em frascos spinners. Ao longo de 10 dias de cultivo as células HKB-11-FVIIr mostraram uma produção acumulada de 152 g de FVIIr, o que corresponde a 304 UI. As células Sk-Hep-1-FVIIr produziram cerca de 202,6 g de FVIIr, o que corresponde a 405,2 UI. Em suma, nossos dados comprovam que as linhagens celulares humanas são eficazes para a produção de fator VII recombinante, uma vez que, utilizando nosso modelo de produção, estas mostraram-se melhores do que a de células murinas (BHK-21) utilizadas pela indústria. Assim, estas linhagens celulares humanas podem ser usadas como uma nova plataforma para a produção de FVII, bem como para outras proteínas recombinantes, de maneira mais segura e com menor risco de desenvolvimento de anticorpos inibidores / Recombinant factor VII (FVIIr) has been the main therapeutic choice for hemophilic patients who develop inhibitors antibidies to conventional treatments (FVIII and FIX). Currently, the comercial product is produced in murine cells (BHK-21) which gives disadvantages considering the complexity of post-translational modifications of these proteins. The insertion of murine residues can be highly immunogenic in humans. Thus the production of proteins for therapeutic use in human cell lines appears as a promising alternative. In this context, the aim of this study was to clone and express the blood coagulation FVII in 3 human cell lines (HepG2, Sk-Hep-1, HKB-11) and select the best cell line for production of recombinant protein. The cells were modified with the lentiviral vector p1054-CIGWS containing the FVII gene and GFP gene marker. After cells modification we observed efficiency of transduction, in which 80% of BHK-21-FVIIr cells showed GFP expression, 73% of HepG2-FVIIr cells, 32% of HKB-11-FVIIr cells and 95% SK- Hep-FVIIr. Gene expression analysis by real-time PCR showed that the three modified human cell lines exhibited RNAm expression relative to FVIIr. When cells were treated with 5 ug/mL vitamin K in culture, the gene expression of FVIIr was similar in the three cell lines (HepG2: 164 563 URE, HKB-11: 119122 and SK-Hep URE: 124919 URE). For FVII activation, the main post translational modification is -carboxylation vitamin-K-dependent which envolves three enzymes, -carboxylase, VKORC1 and calumenina (inhibitor) . Gene expression of these enzymes was evaluated before and after treatment with vitamin K. It was observed that there was an increase in mRNA levels in human cells treated with vitamin K, suggesting that the treatment is capable of activating the enzymes of the vitamin K cycle. Cell growth kinetics showed that modified murine cells BHK-21 have a higher specific growth rate, around 25% more than human cells. However the kinetics of production of recombinant cell lines showed that human cells expressing rFVII 3-fold more rFVII than BHK-21 cells. Due the low rFVII production of murine cells, and the extremely slow growth profile of human cell line HepG2, the recombinant cell lines Sk-Hep-1-rFVII and HKB-11-rFVII have been selected for cultivation tests in suspension using microcarriers in spinners flasks. Over 10 days of cultivation the HKB-11 cells showed a cumulative production of rFVII 152 ug, corresponding to 304 IU and SK-Hep-1 cells showed a rFVII production of 202.6 ug, corresponding to 405.2 IU. In summary, our data demonstrate that human cell lines are effective for producing recombinant factor VII. Using our production model, human cells were better than murine cells (BHK-21) used by the industry. Thus, these human cell lines can be used as a new platform for the FVII production, as well as for other recombinant proteins, with less risk of developing inhibitor antibodies
3

Thrombin activatable fibrinolysis inhibitor (TAFI) in different hemorrhagic and thrombotic conditions /

Antovic, Jovan P., January 2003 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 6 uppsatser.
4

Clonagem e expressão do fator VII de coagulação sanguínea em linhagens celulares humanas / Cloning and expression of coagulation factor VII in human cell lines

Marcela Cristina Corrêa de Freitas 29 May 2015 (has links)
O Fator VII recombinante (FVIIr) tem sido a principal escolha terapêutica dos pacientes hemofílicos que desenvolvem inibidores contra os fatores VIII e IX utilizados como tratamento. Atualmente, o produto utilizado é produzido em células de camundongo (BHK-21), o qual oferece desvantagens considerando a complexidade das modificações pós-traducionais desta proteína e a inserção de glicosilações de origem murina altamente imunogênicas aos seres humanos. Dessa maneira a produção de proteínas para uso terapêutico em linhagens celulares humanas surge como uma alternativa promissora. Dentro desse contexto, o objetivo principal deste trabalho foi clonar e expressar o FVII de coagulação sanguínea em 3 linhagens celulares humanas (HepG2, Sk-Hep, HKB-11), compará-las com a linhagem murina BKH-21, e selecionar a melhor produtora da proteína recombinante. As células foram modificadas com o vetor lentiviral p1054-CIGWS, contendo os genes do FVII e do marcador GFP. Após a modificação das células foi observada uma eficiência de transdução de 80% nas células BHK-21-FVIIr, 73% nas células HepG2-FVIIr, 32% nas células HKB-11-FVIIr e 95% Sk-Hep-FVIIr. Análises da expressão gênica por PCR em Tempo Real mostraram que as três linhagens humanas modificadas apresentaram expressão do RNAm relativo ao FVIIr, sendo que a linhagem celular HepG2 foi a que teve maior expressão de FVIIr, seguida da Sk-Hep-1 e HKB-11. Quando submetidas ao tratamento com vitamina K por um período de 10 dias em cultura, a expressão do gene FVIIr foi semelhante para as três linhagens (HepG2: 164563 URE, HKB-11: 119122 URE e Sk-Hep: 124919 URE). O FVII é uma proteína que para sua ativação, possui como principal modificação pós traducional a -carboxilação vitamina K dependente, que ocorre por meio do ciclo da vitamina K com a participação de 3 enzimas, -carboxilase, VKORC1 e calumenina (inibidor). A expressão gênica dessas enzimas foi avaliada antes e após o tratamento com a vitamina K. Foi possível observar que houve um aumento nos níveis de RNAm nas células humanas tratadas com vitamina K, sugerindo que esta é capaz de ativar as enzimas do ciclo da -carboxilação. A cinética de crescimento celular em garrafas estáticas mostrou que a as células murinas BHK-21 modificadas possuem uma velocidade específica de crescimento 25% mais elevada que das células humanas. Contudo a cinética de produção das linhagens recombinantes mostrou que as células humanas produzem cerca de 3 vezes mais FVIIr do as células BHK-21. Devida a baixa produção de FVIIr na linhagem celular murina, e ao fato de que a linhagem humana HepG2 apresenta um perfil de crescimento extremamente lento, as linhagens recombinantes Sk-Hep-1-FVIIr e HKB-11-FVIIr foram selecionadas para ensaios de cultivo em suspensão utilizando microcarregadores em frascos spinners. Ao longo de 10 dias de cultivo as células HKB-11-FVIIr mostraram uma produção acumulada de 152 g de FVIIr, o que corresponde a 304 UI. As células Sk-Hep-1-FVIIr produziram cerca de 202,6 g de FVIIr, o que corresponde a 405,2 UI. Em suma, nossos dados comprovam que as linhagens celulares humanas são eficazes para a produção de fator VII recombinante, uma vez que, utilizando nosso modelo de produção, estas mostraram-se melhores do que a de células murinas (BHK-21) utilizadas pela indústria. Assim, estas linhagens celulares humanas podem ser usadas como uma nova plataforma para a produção de FVII, bem como para outras proteínas recombinantes, de maneira mais segura e com menor risco de desenvolvimento de anticorpos inibidores / Recombinant factor VII (FVIIr) has been the main therapeutic choice for hemophilic patients who develop inhibitors antibidies to conventional treatments (FVIII and FIX). Currently, the comercial product is produced in murine cells (BHK-21) which gives disadvantages considering the complexity of post-translational modifications of these proteins. The insertion of murine residues can be highly immunogenic in humans. Thus the production of proteins for therapeutic use in human cell lines appears as a promising alternative. In this context, the aim of this study was to clone and express the blood coagulation FVII in 3 human cell lines (HepG2, Sk-Hep-1, HKB-11) and select the best cell line for production of recombinant protein. The cells were modified with the lentiviral vector p1054-CIGWS containing the FVII gene and GFP gene marker. After cells modification we observed efficiency of transduction, in which 80% of BHK-21-FVIIr cells showed GFP expression, 73% of HepG2-FVIIr cells, 32% of HKB-11-FVIIr cells and 95% SK- Hep-FVIIr. Gene expression analysis by real-time PCR showed that the three modified human cell lines exhibited RNAm expression relative to FVIIr. When cells were treated with 5 ug/mL vitamin K in culture, the gene expression of FVIIr was similar in the three cell lines (HepG2: 164 563 URE, HKB-11: 119122 and SK-Hep URE: 124919 URE). For FVII activation, the main post translational modification is -carboxylation vitamin-K-dependent which envolves three enzymes, -carboxylase, VKORC1 and calumenina (inhibitor) . Gene expression of these enzymes was evaluated before and after treatment with vitamin K. It was observed that there was an increase in mRNA levels in human cells treated with vitamin K, suggesting that the treatment is capable of activating the enzymes of the vitamin K cycle. Cell growth kinetics showed that modified murine cells BHK-21 have a higher specific growth rate, around 25% more than human cells. However the kinetics of production of recombinant cell lines showed that human cells expressing rFVII 3-fold more rFVII than BHK-21 cells. Due the low rFVII production of murine cells, and the extremely slow growth profile of human cell line HepG2, the recombinant cell lines Sk-Hep-1-rFVII and HKB-11-rFVII have been selected for cultivation tests in suspension using microcarriers in spinners flasks. Over 10 days of cultivation the HKB-11 cells showed a cumulative production of rFVII 152 ug, corresponding to 304 IU and SK-Hep-1 cells showed a rFVII production of 202.6 ug, corresponding to 405.2 IU. In summary, our data demonstrate that human cell lines are effective for producing recombinant factor VII. Using our production model, human cells were better than murine cells (BHK-21) used by the industry. Thus, these human cell lines can be used as a new platform for the FVII production, as well as for other recombinant proteins, with less risk of developing inhibitor antibodies
5

Effect of dietary fibre on selected haemostatic variables and C-reactive protein / Christina Johanna North

North, Christina Johanna January 2006 (has links)
Motivation: Cardiovascular heart disease (CVD) is the leading cause of death worldwide. Risk markers for CVD include, amongst others, the haemostatic factors tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor type 1 (PAI-1), factor VII (FVII) and fibrinogen and more recently, C-reactive protein (CRP), a sensitive marker of inflammation. Epidemiological studies have demonstrated an inverse association between dietary fibre (DF) consumption and risk factors for CVD and CVD prevalence. Some research indicates that this protection may be related to favourable changes in the haemostatic profile and inflammatory markers. This is applicable for the consumption of total DF, as well as soluble and insoluble fibre. However, clinical intervention trials report conflicting data on the effects of DF on t-PA, PAI-1, FVII, fibrinogen and CRP. In addition, available literature is not clear on the mechanisms through which DF may have favourable effects. Objective: The main objective of this study was to review the results of randomised controlled trials systematically on the effects of DF on the above-mentioned selected haemostatic variables and CRP in healthy adults and subjects with hypertriglyceridaemia and the metabolic syndrome. Methods: Human adult intervention trials, at least two weeks in duration, with an increased and measurable consumption of DF were included. Electronic databases were searched from the earliest record to May/July 2006 and supplemented by crosschecking reference lists of relevant publications. From the literature search, two reviewers identified studies that were rated for quality based on the published methodology. No formal statistical analysis was performed due to the large differences in the study designs of the dietary intervention trials. The primary outcome measures were percentage changes between intervention and control groups, or baseline to end comparisons for t-PA, PAI-1, FVII, fibrinogen and CRP. Results t-PA activity increased significantly (14-167%) over the short and long-term following increased fibre intakes. PAI-1 activity decreased significantly between 15-57% over periods ranging from two to six weeks. These favourable changes in t-PA and PAI-1 occurred in healthy, hypertriglyceridaemic and metabolic syndrome subjects following consumption of diets containing ≥3.3 g/MJ DF and ≥4.5 g/MJ DF respectively. Mechanisms through which DF may affect t-PA and PAI-1 include its lowering effect on insulinaemic and glycaemic responses, decreasing triglycerides which are a precursor of very-low-density lipoproteins, fermentation of DF to short-chain fatty acids, which may reduce free fatty acid concentrations, as well as the role of DF in promoting weight loss. High DF intakes did not have a significant effect on fibrinogen concentrations possibly because of relatively little weight loss, too low DF dosages and maintaining a good nutritional status. Inadequate study designs deterred from meaningful conclusions. Significant decreases in FVll coagulant activity (6-16%) were observed with DF intakes of ≥3.3 g/MJ and concomitant decreased saturated fat intakes and weight loss in healthy and hypertriglyceridaemic subjects. Confounding factors include weight loss and a simultaneous decreased intake of saturated fats. The type of fibre seems to play a role as well. Mechanisms through which DF may reduce FVll concentrations include its effects on triglyceride-rich lipoproteins, insulin and weight loss. Increased DF consumption with dosages ranging between 3.3-7.8 g/MJ were followed by significantly lower CRP concentrations (25-54%), however, simultaneous weight loss and altered fatty acid intakes were also present in all the studies. Mechanisms are inconclusive but may involve the effect of DF on weight loss, insulin, glucose, adiponectin, interleukin-6, free fatty acids and triglycerides. Conclusions: Epidemiological evidence indicates an association between DF and the CVD risk factors t-PA, PAI-1, FVII, fibrinogen and CRP. In general, the risk of CVD may improve with high-fibre intakes as indicated by the favourable changes in some of the parameters. However, simultaneous reduced fat intakes and weight loss presented difficulties in separating out the effects of specific components. Furthermore, DF is consumed in a variety of different forms and different dosages that may have different effects. Overall, the study designs used in the intervention trials prevented significant conclusions. DF did, however, play a role in modifying t-PA, PAI-1, FVII and CRP. Potential effects on fibrinogen were not quantifiable. Recommendations: The results from this investigation provide the motivation for additional controlled clinical research to establish the effect and mechanisms of DF on haemostatic variables and CRP. A critical aspect of future studies would be to set up suitable protocols. The amount of subjects, duration of the trials, confounding factors such as weight loss and altered fat intakes and differentiation between types and dosage of DF are important. DF supplemental studies are recommended as they may be the most suitable method to reach meaningful conclusions. / Thesis (Ph.D. (Nutrition))--North-West University, Potchefstroom Campus, 2007
6

Effect of dietary fibre on selected haemostatic variables and C-reactive protein / C.J. North

North, C. J. (Christina Johanna) January 2006 (has links)
Thesis (Ph.D. (Nutrition))--North-West University, Potchefstroom Campus, 2007.
7

Effect of dietary fibre on selected haemostatic variables and C-reactive protein / Christina Johanna North

North, Christina Johanna January 2006 (has links)
Motivation: Cardiovascular heart disease (CVD) is the leading cause of death worldwide. Risk markers for CVD include, amongst others, the haemostatic factors tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor type 1 (PAI-1), factor VII (FVII) and fibrinogen and more recently, C-reactive protein (CRP), a sensitive marker of inflammation. Epidemiological studies have demonstrated an inverse association between dietary fibre (DF) consumption and risk factors for CVD and CVD prevalence. Some research indicates that this protection may be related to favourable changes in the haemostatic profile and inflammatory markers. This is applicable for the consumption of total DF, as well as soluble and insoluble fibre. However, clinical intervention trials report conflicting data on the effects of DF on t-PA, PAI-1, FVII, fibrinogen and CRP. In addition, available literature is not clear on the mechanisms through which DF may have favourable effects. Objective: The main objective of this study was to review the results of randomised controlled trials systematically on the effects of DF on the above-mentioned selected haemostatic variables and CRP in healthy adults and subjects with hypertriglyceridaemia and the metabolic syndrome. Methods: Human adult intervention trials, at least two weeks in duration, with an increased and measurable consumption of DF were included. Electronic databases were searched from the earliest record to May/July 2006 and supplemented by crosschecking reference lists of relevant publications. From the literature search, two reviewers identified studies that were rated for quality based on the published methodology. No formal statistical analysis was performed due to the large differences in the study designs of the dietary intervention trials. The primary outcome measures were percentage changes between intervention and control groups, or baseline to end comparisons for t-PA, PAI-1, FVII, fibrinogen and CRP. Results t-PA activity increased significantly (14-167%) over the short and long-term following increased fibre intakes. PAI-1 activity decreased significantly between 15-57% over periods ranging from two to six weeks. These favourable changes in t-PA and PAI-1 occurred in healthy, hypertriglyceridaemic and metabolic syndrome subjects following consumption of diets containing ≥3.3 g/MJ DF and ≥4.5 g/MJ DF respectively. Mechanisms through which DF may affect t-PA and PAI-1 include its lowering effect on insulinaemic and glycaemic responses, decreasing triglycerides which are a precursor of very-low-density lipoproteins, fermentation of DF to short-chain fatty acids, which may reduce free fatty acid concentrations, as well as the role of DF in promoting weight loss. High DF intakes did not have a significant effect on fibrinogen concentrations possibly because of relatively little weight loss, too low DF dosages and maintaining a good nutritional status. Inadequate study designs deterred from meaningful conclusions. Significant decreases in FVll coagulant activity (6-16%) were observed with DF intakes of ≥3.3 g/MJ and concomitant decreased saturated fat intakes and weight loss in healthy and hypertriglyceridaemic subjects. Confounding factors include weight loss and a simultaneous decreased intake of saturated fats. The type of fibre seems to play a role as well. Mechanisms through which DF may reduce FVll concentrations include its effects on triglyceride-rich lipoproteins, insulin and weight loss. Increased DF consumption with dosages ranging between 3.3-7.8 g/MJ were followed by significantly lower CRP concentrations (25-54%), however, simultaneous weight loss and altered fatty acid intakes were also present in all the studies. Mechanisms are inconclusive but may involve the effect of DF on weight loss, insulin, glucose, adiponectin, interleukin-6, free fatty acids and triglycerides. Conclusions: Epidemiological evidence indicates an association between DF and the CVD risk factors t-PA, PAI-1, FVII, fibrinogen and CRP. In general, the risk of CVD may improve with high-fibre intakes as indicated by the favourable changes in some of the parameters. However, simultaneous reduced fat intakes and weight loss presented difficulties in separating out the effects of specific components. Furthermore, DF is consumed in a variety of different forms and different dosages that may have different effects. Overall, the study designs used in the intervention trials prevented significant conclusions. DF did, however, play a role in modifying t-PA, PAI-1, FVII and CRP. Potential effects on fibrinogen were not quantifiable. Recommendations: The results from this investigation provide the motivation for additional controlled clinical research to establish the effect and mechanisms of DF on haemostatic variables and CRP. A critical aspect of future studies would be to set up suitable protocols. The amount of subjects, duration of the trials, confounding factors such as weight loss and altered fat intakes and differentiation between types and dosage of DF are important. DF supplemental studies are recommended as they may be the most suitable method to reach meaningful conclusions. / Thesis (Ph.D. (Nutrition))--North-West University, Potchefstroom Campus, 2007
8

Purificação de fatores de coagulação VIII e VII recombinantes para o tratamento das hemofilias A e B produzidos a partir de células humanas / Purification of recombinant coagulation factors VIII and VII obtained from human cells for hemophilia A and B treatement

Granovski, Vladimir 23 January 2018 (has links)
Neste trabalho foram estudados diversos métodos cromatográficos para a purificação de fatores recombinantes de coagulação VII (FVIIr) e VIII (FVIIIr) derivados de linhagens celulares humanas SK-Hep. O FVIIIr é utilizado para o tratamento da Hemofilia A, enquanto o FVIIr é utilizado para o tratamento da Hemofilia B e também a Hemofilia A. Produzir estes fatores em linhagens celulares humanas faz com os padrões de glicosilação, sulfatação e enovelamento destas proteínas sejam extremamente parecidos com os fatores endógenos produzidos no organismo humano. A purificação do FVIIIr através de técnicas de cromatografia multimodais usando a resina CaptoMMC, afinidade usando a resina FVIIISelect e troca iônica (SP-Sepharose) permitiu obter um produto bastante homogêneo e com perfil de banda (por SDS-PAGE) bem definido que demonstrou a presença esperada das cadeias leve e pesada (o Westen-Blott indicou que os anticorpos comerciais reconheceram a cadeia pesada da molécula estudada). As técnicas permitiram uma alta reprodutibilidade do processo onde sequencias de purificação indicaram o mesmo comportamento de perfis cromatográficos e o processo eliminou 99.5% ± 0,5% de proteínas inespecíficas, recuperando até 64% de FVIIIr. O FVIIr foi purificado com apenas uma única técnica cromatográfica usando a resina FVIISelect que isolou a proteína de interesse eliminando cerca de 99% de impurezas, recuperando praticamente todo o produto. O eluido da cromatografia de afinidade foi dialisado em membranas de 5 kDa o que resultou no processo de auto ativação da molécula de FVIIr, resultando em um aumento de sinal de até 5x em relação a quantidade inicial. O gel de SDS-PAGE e o Westen-Blott comprovaram o processo de auto-ativação no qual uma migração de banda de 50 kDa para 30kDa foi observada e os anticorpos comerciais contra FVII foram capazes de detecta-la. O método de purificação também foi bastante reproduzível e o perfil de banda muito semelhante se comparado ao produto comercial existente no mercado. Sendo assim, foi possível obter plataformas de purificação para as proteínas FVIIr e FVIIIr. / In this work, several chromatographic methods were studied for the purification of recombinant clotting factors VII (FVIIr) and VIII (FVIIIr) derived from human SK-Hep cell lines. The FVIIIr is used for the treatment of Hemophilia A, while the FVIIr is used for the treatment of Hemophilia B and Hemophilia A. Producing these factors in human cell lines results in glycosylation, sulphation and folding patterns similar to the endogenous factors produced in the human organism. Purification of FVIIIr by multimodal chromatography techniques using CaptoMMC resin, affinity using FVIIISelect resin and ion exchange (SP-Sepharose) yielded a fairly homogeneous and well-defined band profile (by SDS-PAGE) which demonstrated the expected presence of the light and heavy chains, Westen-Blott indicated that commercial antibodies recognized the heavy chain of the studied molecule. The techniques allowed a high reproducibility of the process where purification sequences indicated the same behavior of chromatographic profiles and the process eliminated 99.5% ± 0.5% nonspecific proteins and recovering up to 64% FVIIIr. FVIIr was purified with only a single chromatographic technique using the FVIISelect resin which isolated the protein by removing about 99% impurities and recovering virtually the entire product. The affinity chromatography eluate was dialyzed on 5 kDa membranes which resulted in the autoactivation process of the FVIIr molecule resulting in a signal increase of up to 5 fold over the initial amount. The SDS-PAGE gel and Westen-Blott demonstrated the auto-activation process where a migration of 50 kDa to 30 kDa band was observed and the commercial antibodies against FVII were able to detect the band. The purification method was also quite reproducible and the band profile very similar compared to the commercial products. Thus, it was possible to obtain purification platforms for the FVIIr and FVIIIr proteins.
9

Purificação de fatores de coagulação VIII e VII recombinantes para o tratamento das hemofilias A e B produzidos a partir de células humanas / Purification of recombinant coagulation factors VIII and VII obtained from human cells for hemophilia A and B treatement

Vladimir Granovski 23 January 2018 (has links)
Neste trabalho foram estudados diversos métodos cromatográficos para a purificação de fatores recombinantes de coagulação VII (FVIIr) e VIII (FVIIIr) derivados de linhagens celulares humanas SK-Hep. O FVIIIr é utilizado para o tratamento da Hemofilia A, enquanto o FVIIr é utilizado para o tratamento da Hemofilia B e também a Hemofilia A. Produzir estes fatores em linhagens celulares humanas faz com os padrões de glicosilação, sulfatação e enovelamento destas proteínas sejam extremamente parecidos com os fatores endógenos produzidos no organismo humano. A purificação do FVIIIr através de técnicas de cromatografia multimodais usando a resina CaptoMMC, afinidade usando a resina FVIIISelect e troca iônica (SP-Sepharose) permitiu obter um produto bastante homogêneo e com perfil de banda (por SDS-PAGE) bem definido que demonstrou a presença esperada das cadeias leve e pesada (o Westen-Blott indicou que os anticorpos comerciais reconheceram a cadeia pesada da molécula estudada). As técnicas permitiram uma alta reprodutibilidade do processo onde sequencias de purificação indicaram o mesmo comportamento de perfis cromatográficos e o processo eliminou 99.5% ± 0,5% de proteínas inespecíficas, recuperando até 64% de FVIIIr. O FVIIr foi purificado com apenas uma única técnica cromatográfica usando a resina FVIISelect que isolou a proteína de interesse eliminando cerca de 99% de impurezas, recuperando praticamente todo o produto. O eluido da cromatografia de afinidade foi dialisado em membranas de 5 kDa o que resultou no processo de auto ativação da molécula de FVIIr, resultando em um aumento de sinal de até 5x em relação a quantidade inicial. O gel de SDS-PAGE e o Westen-Blott comprovaram o processo de auto-ativação no qual uma migração de banda de 50 kDa para 30kDa foi observada e os anticorpos comerciais contra FVII foram capazes de detecta-la. O método de purificação também foi bastante reproduzível e o perfil de banda muito semelhante se comparado ao produto comercial existente no mercado. Sendo assim, foi possível obter plataformas de purificação para as proteínas FVIIr e FVIIIr. / In this work, several chromatographic methods were studied for the purification of recombinant clotting factors VII (FVIIr) and VIII (FVIIIr) derived from human SK-Hep cell lines. The FVIIIr is used for the treatment of Hemophilia A, while the FVIIr is used for the treatment of Hemophilia B and Hemophilia A. Producing these factors in human cell lines results in glycosylation, sulphation and folding patterns similar to the endogenous factors produced in the human organism. Purification of FVIIIr by multimodal chromatography techniques using CaptoMMC resin, affinity using FVIIISelect resin and ion exchange (SP-Sepharose) yielded a fairly homogeneous and well-defined band profile (by SDS-PAGE) which demonstrated the expected presence of the light and heavy chains, Westen-Blott indicated that commercial antibodies recognized the heavy chain of the studied molecule. The techniques allowed a high reproducibility of the process where purification sequences indicated the same behavior of chromatographic profiles and the process eliminated 99.5% ± 0.5% nonspecific proteins and recovering up to 64% FVIIIr. FVIIr was purified with only a single chromatographic technique using the FVIISelect resin which isolated the protein by removing about 99% impurities and recovering virtually the entire product. The affinity chromatography eluate was dialyzed on 5 kDa membranes which resulted in the autoactivation process of the FVIIr molecule resulting in a signal increase of up to 5 fold over the initial amount. The SDS-PAGE gel and Westen-Blott demonstrated the auto-activation process where a migration of 50 kDa to 30 kDa band was observed and the commercial antibodies against FVII were able to detect the band. The purification method was also quite reproducible and the band profile very similar compared to the commercial products. Thus, it was possible to obtain purification platforms for the FVIIr and FVIIIr proteins.
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Avaliação do potencial de crescimento e produção de proteínas recombinantes de células humanas adaptadas para crescimento em suspensão e meios de cultura livres de soro fetal bovino / Evaluation of growth and recombinant protein production of human cell lines adapted to serum-free suspension cultures

Biaggio, Rafael Tagé 29 October 2018 (has links)
Linhagens celulares humanas tem despertado interesse como plataformas de produção de proteínas terapêuticas recombinantes por sua capacidade de realizar modificações pós-traducionais complexas e de modo similar à humana, sem gerar epítopos imunogênicos como ocorre com proteínas produzidas em células de mamíferos. Para a produção de uma proteína com correta qualidade terapêutica, as agências regulatórias recomendam processos livres de componentes animais de modo a evitar contaminação com vírus e príons. Deste modo, esse trabalho visa a produção do fator VII da coagulação sanguínea recombinante (FVIIr) utilizada no tratamento de hemofílicos com inibidores em células humanas adaptadas para meios de cultura livres de soro fetal bovino. As linhagens humanas SK-Hep-1, HKB-11 e Huh-7 foram adaptadas para suspensão e meios livres de soro fetal bovino (SFB). Essas células adaptadas foram transfectadas de forma transiente com o vetor lentiviral p1054-GFP e o reagente polietilenimina. No entanto, a baixa eficiência de transfecção nas células SK-Hep-1 e Huh-7 mostraram que essas linhagens são difíceis de transfectar por esse método, e mesmo a transfecção da célula HKB-11 só foi possível após a variação de alguns parâmetros, resultando em uma transfecção de 49,5% de células HKB-11 GFP-positivas. Desta forma, a expressão estável foi avaliada e as células adaptadas foram transduzidas com um ciclo de lentivírus (MOI = 1) contendo o vetor p1054-FVII. Foram observadas porcentagens de células GFP-positivas acima de 35% nas três linhagens celulares humanas modificadas. As células transduzidas foram submetidas a dois processos de sorting por citometria de fluxo, no qual a população obtida apresentava mais de 90% de células GFP-positivas. As três células foram avaliadas com relação à expressão de FVIIr após a adição de vitamina K no cultivo, no entanto, não foi possível detectar níveis de FVIIr no sobrenadante de 48 horas do cultivo dessas células pelo teste ELISA. As células foram transduzidas com um segundo ciclo de lentivírus (MOI = 2). A quantificação por ELISA do sobrenadante de 48 horas de cultivo das três células detectou 240,96 ng/mL, 217,42 ng/mL e 78,46 ng/mL de FVII total, respectivamente, nos cultivos das células HKB-11-F7-2C, SK-Hep-1-F7-2C e Huh-7-F7-2C. A expressão relativa de RNA mensageiro por RT-PCR também foi observada nos três cultivos. Paralelamente, foi analisado o proteoma das três células adaptadas e não-adaptadas em triplicata sendo identificadas de forma abundante proteínas do citoesqueleto, do metabolismo celular, da síntese, enovelamento e degradação de proteínas, relacionadas à apoptose, ao ciclo celular e ao crescimento, proteínas contra estresse oxidativo e osmótico, com ação antioxidante, entre outras. / Human cell lines have attracted great interest as a plarform for recombinant therapeutic proteins production, due their ability to perform complex posttranslational modification in a similar manner to human proteins. These proteins do not carry immunogenic epitopes as occurs with proteins produced in mammalian cells. These therapeutic proteins should be produced in a animal-free process avoiding virus and prion contamination, as recommended by regulatory agencies for quality control. Thus, this work aims the production of recombinant blood coagulation factor VII (rFVII) used in the treatment of hemophiliacs with inhibitors in human cell lines adapted to serum-free suspension cultures. Human cell lines SK-Hep-1, HKB-11 and Huh-7 were adapted to suspension and serum-free media. These adapted cells were transiently transfected with p1054-GFP lentiviral vector and the polyethyleneimine reagent. However, low transfection efficiency in SK-Hep-1 and Huh-7 cells showed that these cells are difficult to transfect by this method, and even transfection of HKB-11 cell was only possible after varying some parameters, resulting in a 49,5% HKB-11 GFP-positive cells. Stable transfection was assessed and adapted cells were transduced with lentivirus particles containing p1054-FVII vector in one cycle (MOI=1). Percentages of GFP-positive cells above 35% were observed in three modified human cell lines. Transduced cells were sorted by FACS and more than 90% of GFP-positive cells were obtained. The expression of rFVII were evaluated by ELISA test after vitamin K supplementation, however, it was not possible to detect FVII levels in the 48 hour culture supernatant. Cells were transduced again with a second lentivirus cycle (MOI = 2). ELISA quantification of the 48 hour culture supernatant detected 240,96 ng/mL, 217,42 ng/mL and 78,46 ng/mL total FVII, respectively, in the cultures of HKB-11-F7-2C, SK-Hep-1-F7-2C and Huh-7-F7-2C cells. Relative expression of mRNA by RT-PCR was also observed in the three cultures assessed. In parallel, a proteomic analysis of adapted and non-adapted cells was performed in triplicate. Proteins related to cellular metabolism, cytoskeletal structure, apoptosis, cell cycle and cell growth, against oxidative and osmotic stress, antioxidant action were found.

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