Orientador: Margareth Castro Ozelo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-24T11:38:04Z (GMT). No. of bitstreams: 1 Montalvao_Silmara_M.pdf: 5511908 bytes, checksum: e7e6cf52da6e5f3fb92bce534c8e27ec (MD5) Previous issue date: 2014 / Resumo: Os principais problemas relacionados ao tratamento de pacientes portadores de hemofilia A estão relacionados ao uso terapêutico de fator VIII (FVIII), sendo estes o desenvolvimento de anticorpos neutralizantes anti-FVIII (inibidores), e o desenvolvimento de reações anafiláticas, que são eventos raros, no entanto potencialmente graves. As informações quanto aos isotipos de imunoglobulinas associados a estas duas situações clínicas ainda é limitado. O objetivo deste projeto foi avaliar as características da resposta imune humoral em pacientes com hemofilia A que apresentam inibidor e/ou em condição de reação alérgica ao FVIII. Para estas análises três metodologias foram aplicadas, (1) determinação de anticorpos inibitórios por método de Bethesda-Nijmegen, (2) determinação do isotipo de imunoglobulinas envolvidas subclasses da IgG, IgM e IgE anti-FVIII, por método de ELISA e (3) determinação de citocinas por método multiplex BDTM CBA® (cytometric bead array). Esse projeto foi dividido em três estudos. No primeiro estudo, foram analisadas amostras de 25 pacientes brasileiros com hemofilia A, sendo 44% destes afrodescendentes. Todos os pacientes receberam exclusivamente terapia de reposição com concentrado de FVIII derivado de plasma (pdFVIII) e produtos bypass após o desenvolvimento de inibidor. Cinco pacientes deste grupo foram acompanhados por uma análise longitudinal no período de até três anos. No segundo estudo, 4 pacientes com hemofilia A com inibidor foram avaliados no período em que foram tratados através do protocolo de indução de imunotolerância (ITI) para erradicação do inibidor, também em análise longitudinal. O terceiro consistiu da avaliação de incidência de reação alérgica em pacientes com hemofilia A. Três de 322 pacientes (0,9%) apresentaram reação alérgica após a exposição exclusivamente para pdFVIII durante os últimos quinze anos em nosso centro. Os resultados evidenciaram que a subclasse IgG4 é a principal na modulação em presença de anticorpos inibitórios, enquanto a IgG1 na maior parte das análises estava presente junto a baixos títulos de inibidor.Durante o tratamento de ITI os níveis das interleucinas anti-inflamatórias IL-4 e IL-6 acompanharam o decaimento dos títulos de inibidor e IgG4 nos pacientes que obtiveram sucesso ao tratamento. Além disso, no decorrer do protocolo observou-se uma resposta polarizada para o tipo Th1 como padrão de resposta na conquista da tolerância completa ao FVIII. No contexto da reação alérgica, apenas um dos três pacientes apresentou reatividade da IgE que foi exclusiva ao pdFVIII, sendo negativa no ensaio do IgE anti-rFVIII (anti-fator VIII recombinante), demonstrando que a reatividade não foi específica ao FVIII. O entendimento resposta imune humoral em pacientes com hemofilia A, incluindo a participação da IgG4 e IgG1 no mecanismos envolvendo a presença e erradicação dos inibidores e da IgE na reação alérgica, possibilita ampliar conceitos estabelecidos dos mecanismos envolvidos nessas duas situações. Isso poderá auxiliar no desenvolvimento de novos produtos menos imunogênicos e de novas estratégias para a indução de tolerância ao FVIII, que tenham maior eficiência e melhor custo benefício / Abstract: The main problems related to the treatment of hemophilia A patients are linked to the use of therapeutic factor VIII (FVIII). First, the development of neutralizing antibodies against FVIII (inhibitors), and second development of anaphylactic reactions, which are rare, however potencialy severe. The knowledge about the immunoglobulin isotypes associated with these two clinical situations is still limited.The aim of this project was to evaluate the characteristics of the humoral immune response in patients with hemophilia A who have inhibitors and/or allergic reaction to FVIII. For these analyzes three methods were used (1) inhibitory anti-FVIII antibodies assay by Bethesda-Nijmegen (2) immunoglobulins isotype ELISA assay for anti-FVIII IgG subclasses, IgM and IgE and (3) cytokines assay by BDTM Cytometric bead array (BD CBA®) multiplex method. This project was divided in three studies. In the first study, we analyzed samples from 25 Brazilian hemophilia A patients with 44% African-descents. All patients received exclusively replacement therapy with plasma-derived (pdFVIII) concentrates, and bypassing agents after the development of inhibitors. Five patients from this group were followed for a longitudinal analysis in a period up to three years. In the second study, 4 hemophilia A patients with inhibitor were evaluated also in longitudinal analyses, during the induction of immunotolerance (ITI) treatment for the eradication of the inhibitor. The third study included the evaluation of the incidence of allergic reaction among hemophilia A patients. Three out of 322 patients (0.9%) had allergic reaction after exclusively exposure to pdFVIII during the last fifteen years in our center. The results of these studies demonstrated that IgG4 subclass is the main immunoglobulin involved in the modulation of the inhibitory antibodies, while IgG1 is associated with low-titer inhibitors. During the ITI protocol, the anti- inflammatory interleukins, IL-4 and IL-6 decreased following the IgG4 reduction among the patients that achieved success in the ITI treatment. In addition, during the ITI protocol it was observed a polarized Th1 immune response after the complete success achievement. In the context of allergic reaction, only one out of three patients presented IgE reactivity that was exclusively to pdFVIII, and the assay IgE anti-rFVIII (anti-recombinant FVIII) was negative, confirming that the reativity was not specific to FVIII. The understanding of the humoral immune response in hemophilia A patients, including the role of IgG4 and IgG1 in the mechanisms involving the presence and eradication of inhibitors, and the participation of IgE in allergic reaction, allows to better understand the established concepts of the mechanisms involved in these two situations. This may help the development of less immunogenic new products and new strategies for induction of tolerance to FVIII, with higher efficiency and best value / Mestrado / Clinica Medica / Mestra em Clínica Médica

Orientador: Joyce Maria Annichino-Bizzacchi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-27T01:02:06Z (GMT). No. of bitstreams: 1 DePaula_LaisIvinaSilva_M.pdf: 1198632 bytes, checksum: 0ba443fa4dbfb9c64ad09eacb865b1bb (MD5) Previous issue date: 2015 / Resumo: Problemas associados à aterosclerose são a causa mais comum de morte na população ocidental. A aterosclerose é uma doença inflamatória, e existe uma associação da coagulação com processos inflamatórios e complicações da doença arterial. Estudos populacionais inicialmente demonstraram uma diminuição do risco de infarto agudo do miocárdio em homens hemofílicos, quando comparados com controles pareados por idade e sexo. Contudo estudos subsequentes não confirmaram esses achados, havendo inclusive um estudo que mostrou aumento do risco de doença aterosclerótica e infarto em pacientes hemofílicos. Um dos fatores que deve ter tido importante papel nessa mudança foi o aumento da sobrevida dos pacientes a partir de 1999, com o advento de terapêuticas mais eficazes. Este estudo teve como objetivo investigar o papel da deficiência grave de fator IX (FIX), no desenvolvimento da doença aterosclerótica, em um modelo de dislipidemia, utilizando animais da linhagem C57Bl/6 deficientes de apolipoproteína E (APOE -/-). Comparamos grupos de animais com deficiência de apoE com ou sem deficiência de FIX (hemofílicos B - HB), através da avaliação quantitativa das lesões, na raiz e em toda sua extensão aórtica; e caracterização histológica das lesões na raiz aórtica por imunofluorecência. Nossos resultados mostraram que os animais com hemofilia B e deficiência de apoE apresentaram o mesmo grau de formação de placa aterosclerótica quando comparados com o grupo controle (APOE -/-), com 8 e 22 semanas de dieta. Portanto, a deficiência do fator IX não protegeu contra a formação de lesões ateroscleróticas na raiz e em toda extensão aórtica. O mesmo ocorreu na avaliação qualitativa, quando comparamos a porcentagem total de macrófagos e de células musculares lisas. Independente dos seus elevados níveis de colesterol e triglicerídeos. Contudo, foi evidente a diminuição na quantidade de macrófagos M1, através da produção de IL - 1?, em comparação aos camundongos controles, deficientes apenas de apoE. Um dado intrigante é que apesar de termos observado uma diminuição de macrófagos M1 nos animais hemofílicos, isso não foi acompanhado por uma diminuição nas lesões ateroscleróticas. Portanto, apesar da hipocoagulabilidade e do perfil de resposta dos macrófagos, nossos resultados sugerem que outros fatores foram mais importantes no desenvolvimento da aterosclerose. Nossos resultados corroboram os achados mais recentes de que pacientes hemofílicos também são susceptíveis ao desenvolvimento de doença aterosclerótica, incluindo doença coronariana / Abstract: Problems associated with atherosclerosis are the most common cause of death in the western population. Atherosclerosis is an inflammatory disease, and there is a coagulation associated with inflammatory processes and complications of arterial disease. Population studies initially demonstrated a decreased risk of acute myocardial infarction in men hemophiliacs compared with controls matched for age and sex. But subsequent studies have not confirmed these findings, including having a study that showed increased risk of atherosclerotic disease and stroke in hemophilia patients. One of the factors that must have played an important role in this change was the increased survival of patients since 1999, with the advent of more effective therapies. This study aimed to investigate the role of severe deficiency of factor IX (FIX), in the development of atherosclerosis, dyslipidemia in a model using animals C57BL strain / 6 deficient apolipoprotein E (APOE - / -). Groups of animals compared with apoE-deficient or without FIX deficiency (hemophilia B - HB) by quantitative evaluation of lesions in the root and aortic its entire extension; and histological characterization of the lesions in the aortic root by immunofluorescence. Our results showed that animals with hemophilia B and apoE deficiency showed the same degree of atherosclerotic plaque formation when compared with the control group (APOE - / -), with 8 and 22 weeks of diet. Therefore, factor IX deficiency does not protect against the formation of atherosclerotic lesions in the aortic root and throughout extension. The same occurred in the qualitative evaluation, when comparing the total percentage of macrophages and smooth muscle cells. Whatever your high cholesterol and triglycerides. However, it was apparent decrease in the amount of M1 macrophages by IL - 1? compared to control mice, apoE deficient only. A given intriguing is that although we observed a decrease of M1 macrophages in hemophiliacs animals, this was not accompanied by a decrease in atherosclerotic lesions. Therefore, despite the hypocoagulability and macrophage response profile, our results suggest that other factors are more important in the development of atherosclerosis. Our results support the latest findings that hemophilia patients are also susceptible to developing atherosclerosis, including coronary heart disease / Mestrado / Fisiopatologia Médica / Mestra em Ciências

Permanent repair of the F9 gene is a significant goal to cure Hemophilia B disease. Advanced gene therapy using CRISPR/Cas9 system can increase circulation level of Factor IX proteins to a significant level without the need of demanding infusions of FIX concentrates. Induced pluripotent stem cells represent an ideal cell for gene therapy because patient-derived cells could be reprogrammed into iPSCs, genetically modified, selected, expanded and then induced to differentiate into fully functional hepatocytes in vitro. This study covered a portion of a 5-year project which ultimately aims at establishing therapeutic results in transgenic Hemophilia B mice by injecting genetically corrected iPSC-derived hepatocytes into the liver. The purpose of this thesis is to summarize what has been completed up to now: generation of the proper model of Hemophilia B human iPSCs using CRISPR/Cas9-mediated genome editing and differentiation of healthy and disease specific iPSCs into hepatocytes which will allow disease modelling to look for cell function, viability, homogeneity and drug screening. Further research will be done to effectively knock-in the F9 allele into liver safe harbor site of disease specific iPSCs, which will express FIX at a significant level to show therapeutic effects.

A 2009-2010 National Assessment Survey of youth with special needs such as hemophilia showed that 40% of youth between the ages of 12 and 17 had a transition plan before transitioning to adult care services. The lack of a transition plan caused youth to fall into a fragmented care gap when transition services are inadequate. During the gap, youth with hemophilia increased use of the emergency room and were hospitalized for complications such as frequent joint or muscle bleeding and joint disability. As a result, the health status of affected youth becomes fragile and health care costs escalate. The practice problem for this DNP project was the need for transition education and planning for youth with hemophilia. The practice-focused question asked whether a transition quick guide for youth (aged 12-17) with hemophilia enabled them to increase their knowledge of self-care management skills as evidenced by increased post-test scores of transition readiness. The purpose of the project was to prepare youth with hemophilia who are 12 to 17 years old to make a smooth transition from pediatric to the adult hemophilia clinic by using a transition quick guide to educate them about hemophilia and self-care management. The model used to inform this project was the plan-do-study-act (PDSA), a quality improvement method used to test a relatively small change of transition services within the hemophilia clinic. Sources of evidence were taken from 10 participants with hemophilia. Data to assess the project outcome was collected from pre and post educational interventions, along with demographic data to characterize the sample population from participants' clinic records. A descriptive statistics approach to obtain percentage differences between pretest and post test outcome data was used to answer the project question. Pretest data scores on a 10-point scale were between 19% (lowest score for pretest), and 58% (highest score for pretest). Post test scores after educational session were between 42% (lowest score for post test scores), and 95% (highest post test score). The percentage differences between pretest and post test showed a 14% increase in knowledge, showing that knowledge increased using the transition quick guide. The implication for positive social change was that youth who are adequately prepared for the transition to adult care services will avoid unnecessary health complications and enjoy an improved quality of life.

Hemophilia is a genetic disorder that is caused by deficiencies in coagulation factor VIII and factor IX. Optimal management of hemophilia requires tailoring the dose of treatment to the individual patient’s need. This tailoring is based on several clinical considerations, for example, bleeding phenotype and desired level of activity, and estimated individual pharmacokinetic (PK) parameters. While a classical PK approach would require several post infusion blood samples taken over multiple days, a population PK approach might enable individual assessment using fewer samples. Health information technologies can support implementation of sophisticated, easily available, point-of care resources to estimate PK values with a population approach. The Web Accessible Population Pharmacokinetic Service-Hemophilia (WAPPS-Hemo) is a proposal for such a solution, developed at McMaster University. Once tested, it will be offered to hemophilia centres worldwide. The objective of the study was to investigate the ease of use (usability) of the WAPPS-Hemo web interface among clinicians and other people who treat hemophilia through two iterative cycles of usability testing. The total number of participants was 13, and they were physicians, nurses and research coordinators. The think aloud technique was selected for testing to gain feedback and comments on the participants’ thought processes while interacting with the system and discover interface design problems. Additionally, the System Usability Scale (SUS) questionnaire was used to obtain data on user satisfaction. The initial assessment of the prototypal WAPPS-Hemo interface with SUS reported a score of 70.5, which is considered an above average score. We received many useful suggestions through two iterations of user testing, ending with a final SUS score of 73 after implementation of the suggested improvements. Verbal feedback from users in the second round showed that users experienced an easier and more intuitive interaction with the system. Usability testing and analyses were conducted in this study to discover user interface issues and to determine the usability and learnability of the WAPPS-Hemo service among various potential users. Through iterative cycles, application of the think aloud technique, and the SUS questionnaire, we optimized the usability of the WAPPS- Hemo program and have moved to implementation (June 2015). / Thesis / Master of Science (MSc)

Gene therapy for Hemophilia A (HA) using the recombinant Adeno-associated virus (rAAV) offers an alternative to classic treatment, which consists of FVIII protein infusions. However, due to limitations associated with rAAV and the FVIII protein itself, the end result is a transgene expression below therapeutic limits. One approach to improving the therapeutic value of rAAV gene therapy for HA is to engineer a more active FVIII protein through genetic modifications. Preliminary testing revealed that canine FVIII Light Chain (kLC) enhances coagulation activity, and that it would be possible to improve FVIII activity through modifications of the light chain. Through the process of engineering, evaluation, and negative selection of kLC, a final construct was engineered. The hLC-K12 is a human Light Chain (hLC) construct containing 12 amino acid changes that work together to enhance coagulation activity. A comparison of the FVIII clotting activity to the amount of protein produced determined that hLC-K12 produced a 3.28 fold increase in specific activity over hLC in vitro. Similar in vitro results were observed when hLC-k12 was tested with the X5 heavy chain (X5HC), a heavy chain that has been genetically modified to enhance production. CD4KO/HA mice were injected with a rAAV vector carrying the hLC-K12 gene in conjugation with a rAAV vector carrying the X5HC gene. Replacing the hLC vector with the hLC-K12 vector produced an average 7.43 fold increase in FVIII clotting activity. An ELISA assay revealed no significant difference between productions of the heavy or light chains at any time point. By comparing the clotting activity to the amount of protein produced, it was determined that the increase in coagulation activity was due to an increase in specific activity. In fact, replacing the hLC vector with the hLC-K12 vector resulted in an average 5.8 fold increase in FVIII specific activity. The K12 modifications were evaluated using a single chain FVIII conformation. In vitro, the addition of the K12 mutations to the human heavy chain, hHCK12BDD, resulted in a 4.3 fold increase in clotting activity, but no increase in protein production. There was however, a 3.3 fold increase in specific activity of the protein. Adding the K12 mutations to the X5 heavy chain, X5K12BDD, in vitro, resulted in a 2.7 fold increase in clotting activity and a 1.42 fold increase in specific activity of the protein. Single chain rAAV vectors were packaged and delivered to CD4KO/HA mice. Compared to mice injected with hFVIIIBDD, the hHCK12BDD produced an average 4.6 fold increase in clotting activity. An ELISA revealed no significant difference in production between these two groups. However, mice injected with hHCK12BDD produced FVIII with an average of 4.13 fold increase in specific activity. Similarly, when compared to mice injected with X5FVIIIBDD, the X5K12BDD produced an average 2.14 fold increase in clotting activity. An ELISA assay demonstrated no significant increase in protein production between these two groups. However, when compared to X5BDD, mice injected with the X5K12BDD vector produced FVIII with an average 1.98 fold increase in specific activity. Results demonstrate that the K12 light chain modifications are able to enhance clotting activity of hFVIII both in vitro and in vivo, using either a dual chain or single chain delivery method. In order to determine the mechanism of enhancement, hFVIIIBDD and hHCK12BDD protein was partially purified and tested for activity. Results demonstrated that the hHCK12BDD protein produced a specific activity of 39,153.69 Units/mg, which is a 6.28 fold increase over hFVIIIBDD specific activity, which was 6,237.92 Units/mg. Measurement of conversion from FX to FXa revealed that the hHCK12BDD protein generated a higher amount of FXa at a quicker rate. In conclusion, these results provide evidence that the K12 modifications enhance specific activity through an increase in FXa generation. / Microbiology and Immunology

Hemophilia B is a debilitating and life-threatening disorder caused by a deficiency in or dysfunction of factor IX (FIX), a complex plasma glycoprotein required for the formation and maintenance of blood clots. Treatment of hemophilia B involves infusion of replacement FIX currently derived from two sources: FIX purified from pools of human plasma (pd-FIX) and a single recombinant FIX product generated in genetically engineered Chinese hamster ovary (CHO) cells. Both of these FIX products are prohibitively expensive, limiting of the treatment options of hemophiliacs worldwide. As a result, a more abundant and affordable FIX product would greatly improve the life prospects for hemophiliacs. The biological activity of FIX is dependent upon its numerous post-translational modifications (PTMs), including gamma-carboxylation, proteolytic maturation, phosphorylation, sulfation, and glycosylation. Of these PTMs, those known to be vital for activity are gamma-carboxylation of multiple glutamate residues near the N-terminus and proteolytic cleavage of the FIX propeptide. When expressed at a high rate in exogenous expression systems, however, the ability of current systems to effect the necessary PTMs is severely rate limited, restricting the production of active FIX. The transgenic pig bioreactor represents a promising source for the production of large quantities biologically active FIX due to its demonstrated ability to perform the required FIX PTMs. It was the goal of this study to characterize the PTM structure and the resulting function of recombinant FIX when expressed at 1-3 mg/ml in the transgenic pig mammary epithelium (tg-FIX). It was found that the expressed tg-FIX is comprised of a heterogeneous mixture of FIX PTM isoforms. This mixture represents a spectrum of tg-FIX molecules of varying gamma-carboxyglutamic acid (Gla) and propeptide content, indicating that rate limitations in effecting these PTMs are present. A purification process was developed utilizing heparin-affinity chromatography to purify the total population of tg-FIX from pig milk, a complex multi-phase feedstock. Subsequently, a process was developed to fractionate the total population of tg-FIX into subpopulations based upon the extent of post-translational modification. Q ion-exchange chromatography was utilized to fractionate tg-FIX based upon molecular acidity which was found to be correlated to both biological activity and Gla content. The resulting biologically active tg-FIX population contained an average of 7 of the 12 Gla residues found in pd-FIX. Immuno-affinity chromatography was subsequently utilized to further fractionate tg-FIX into mature tg-FIX and propeptide-containing tg-FIX populations. The isolated FIX PTM populations were subjected to functional analysis by investigating in vitro clotting activity, activation by factor XIa, and in vivo pharmacokinetics. From this analysis it was found that mature tg-FIX with an average 7 Gla residues, representing approximately 9% of the total tg-FIX produced, exhibits wild-type in vitro clotting activity and normal activation by factor XIa. The remainder of the tg-FIX produced, characterized by either a lower Gla content or the presence of the propeptide, was found to be inactive and displayed less efficient activation by factor IXa. In an in vivo pharmacokinetic study in the hemophilia B mouse model, biologically active tg-FIX was found to possess altered circulating properties. Tg-FIX was characterized by a lower recovery, approximately one-sixth that of pd-FIX, but an extended circulation half-life. From this study it was found that the mean residence time of tg-FIX after injections is approximately twice that observed for pd-FIX. These altered pharmacokinetic properties are likely linked to the unique tg-FIX PTM structure, perhaps through altered endothelial cell binding characteristics caused by the reduced Gla content. / Ph. D.

<p>Electrostatic interaction is a strong force that attracts positively and negatively charged molecules to each other. Such an interaction is formed between positively charged polycationic polymers and negatively charged nucleic acids. In this dissertation, the electrostatic attraction between polycationic polymers and nucleic acids is exploited for applications in oral gene delivery and nucleic acid scavenging. An enhanced nanoparticle for oral gene delivery of a human Factor IX (hFIX) plasmid is developed using the polycationic polysaccharide, chitosan (Ch), in combination with protamine sulfate (PS) to treat hemophilia B. For nucleic acid scavenging purposes, the development of an effective nucleic acid scavenging nanofiber platform is described for dampening hyper-inflammation and reducing the formation of biofilms.</p><p>Non-viral gene therapy may be an attractive alternative to chronic protein replacement therapy. Orally administered non-viral gene vectors have been investigated for more than one decade with little progress made beyond the initial studies. Oral administration has many benefits over intravenous injection including patient compliance and overall cost; however, effective oral gene delivery systems remain elusive. To date, only chitosan carriers have demonstrated successful oral gene delivery due to chitosan’s stability via the oral route. In this study, we increase the transfection efficiency of the chitosan gene carrier by adding protamine sulfate to the nanoparticle formulation. The addition of protamine sulfate to the chitosan nanoparticles results in up to 42x higher in vitro transfection efficiency than chitosan nanoparticles without protamine sulfate. Therapeutic levels of hFIX protein are detected after oral delivery of Ch/PS/phFIX nanoparticles in 5/12 mice in vivo, ranging from 3 -132 ng/mL, as compared to levels below 4 ng/mL in 1/12 mice given Ch/phFIX nanoparticles. These results indicate the protamine sulfate enhances the transfection efficiency of chitosan and should be considered as an effective ternary component for applications in oral gene delivery.</p><p>Dying cells release nucleic acids (NA) and NA-complexes that activate the inflammatory pathways of immune cells. Sustained activation of these pathways contributes to chronic inflammation related to autoimmune diseases including systemic lupus erythematosus, rheumatoid arthritis, and inflammatory bowel disease. Studies have shown that certain soluble, cationic polymers can scavenge extracellular nucleic acids and inhibit RNA-and DNA-mediated activation of Toll-like receptors (TLRs) and inflammation. In this study, the cationic polymers are incorporated onto insoluble nanofibers, enabling local scavenging of negatively charged pro-inflammatory species such as damage-associated molecular pattern (DAMP) molecules in the extracellular space, reducing cytotoxicity related to unwanted internalization of soluble cationic polymers. In vitro data show that electrospun nanofibers grafted with cationic polymers, termed nucleic acid scavenging nanofibers (NASFs), can scavenge nucleic acid-based agonists of TLR 3 and TLR 9 directly from serum and prevent the production of NF-ĸB, an immune system activating transcription factor while also demonstrating low cytotoxicity. NASFs formed from poly (styrene-alt-maleic anhydride) conjugated with 1.8 kDa branched polyethylenimine (bPEI) resulted in randomly aligned fibers with diameters of 486±9 nm. NASFs effectively eliminate the immune stimulating response of NA based agonists CpG (TLR 9) and poly (I:C) (TLR 3) while not affecting the activation caused by the non-nucleic acid TLR agonist pam3CSK4. Results in a more biologically relevant context of doxorubicin-induced cell death in RAW cells demonstrates that NASFs block ~25-40% of NF-ĸβ response in Ramos-Blue cells treated with RAW extracellular debris, ie DAMPs, following doxorubicin treatment. Together, these data demonstrate that the formation of cationic NASFs by a simple, replicable, modular technique is effective and that such NASFs are capable of modulating localized inflammatory responses. </p><p>An understandable way to clinically apply the NASF is as a wound bandage. Chronic wounds are a serious clinical problem that is attributed to an extended period of inflammation as well as the presence of biofilms. An NASF bandage can potentially have two benefits in the treatment of chronic wounds by reducing the inflammation and preventing biofilm formation. NASF can prevent biofilm formation by reducing the NA present in the wound bed, therefore removing large components of what the bacteria use to develop their biofilm matrix, the extracellular polymeric substance, without which the biofilm cannot develop. The NASF described above is used to show the effect of the nucleic acid scavenging technology on in vitro and in vivo biofilm formation of P. aeruginosa, S. aureus, and S. epidermidis biofilms. The in vitro studies demonstrated that the NASFs were able to significantly reduce the biofilm formation in all three bacterial strains. In vivo studies of the NASF on mouse wounds infected with biofilm show that the NASF retain their functionality and are able to scavenge DNA, RNA, and protein from the wound bed. The NASF remove DNA that are maintaining the inflammatory state of the open wound and contributing to the extracellular polymeric substance (EPS), such as mtDNA, and also removing proteins that are required for bacteria/biofilm formation and maintenance such as chaperonin, ribosomal proteins, succinyl CoA-ligase, and polymerases. However, the NASF are not successful at decreasing the wound healing time because their repeated application and removal disrupts the wound bed and removes proteins required for wound healing such as fibronectin, vibronectin, keratin, and plasminogen. Further optimization of NASF treatment duration and potential combination treatments should be tested to reduce the unwanted side effects of increased wound healing time.</p> / Dissertation

A Hemofilia A é uma doença sanguínea condicionada por gene localizado no cromossomo X. É causada pela deficiência parcial ou total da atividade do Fator VIII (FVIII), uma glicoproteína plasmática cuja função é necessária para a coagulação normal do sangue. Devido às dificuldades encontradas para o reconhecimento direto da mutação no gene F8, o diagnóstico das portadoras é feito de forma indireta, isto é, por análise de ligação com marcadores polimórficos localizados dentro ou próximos ao gene que permite determinar a co-segregação do haplótipo e da mutação na família sob estudo e, desta maneira, detectar o estado de portadora e, eventualmente, auxiliar no diagnóstico pré-natal. O presente trabalho teve por objetivo avaliar o poder de alguns desses marcadores na diferenciação das populações e determinar o grau de sua informatividade para o diagnóstico e aconselhamento genético de famílias afetadas, bem como verificar o eventual uso forense de tais marcadores. Foram então determinadas as frequências alélicas e haplotípicas, diversidade genética, diferenciação populacional, desequilíbrio de ligação e composição ancestral de quatro microssatélites intragênicos (IVS 1, IVS 13, IVS 22, IVS 25.3), localizados em introns do F8, e um extragênico (IKBKG) em amostras de populações brasileiras urbanas (indivíduos normais de São Paulo, Rio Grande do Sul e Pernambuco), de quilombos (Mimbó, Sítio Velho e Gaucinha localizados no Estado do Piauí) e Ameríndios (Tikúna, Baníwa e Kashináwa). As análises, quando cabível, incluíram um grupo de pacientes hemofílicos. O DNA dos sítios polimórficos foi amplificado por PCR, os produtos separados em PAGE e corado por nitrato de prata. Para as análises estatísticas foram empregados programas já considerados de uso rotineiro. Os parâmetros de diversidade mostraram diferenças entre as amostras populacionais analisadas. Tais diferenças regionais nas frequências alélicas devem ser levadas em conta quando o diagnóstico indireto da Hemofilia A estiver sendo realizado. Com exceção do IKBKG, todos os demais microssatélites apresentaram altas taxas de heterozigose. Usando tais marcadores, o diagnóstico foi possível em 10 das 11 famílias analisadas. Os microssatélites IVS 22, IVS 1, IVS 13, IVS 25.3 e IKBKG foram informativos em 63,6% (7/11), 54.5% (6/11), 54.5% (6/11), 45.5% (5/11) e 18.2% (2/11) dos casos, respectivamente, demonstrando a eficácia do uso desses microssatélites no diagnóstico pré-natal e na identificação de portadoras na população brasileira. / Hemophilia A is a bleeding disorder conditioned by a gene located on the X chromosome and caused by partial or total deficiency of the Factor VIII (FVIII) activity, a plasma glycoprotein whose function is necessary for normal blood clotting. Due to difficulties faced on direct recognition of the F8 gene mutation, carrier diagnosis is done indirectly by linkage analysis with polymorphic markers located within or near the gene. These markers may determine the haplotype and the mutation co-segregation within the studied family, and thus detect the carrier status and possibly assist in prenatal diagnosis. This study aimed to evaluate the power of some of these markers in population differentiation and to determine their degree of informativeness for diagnosis and genetic counseling of affected families, as well as to verify the possible forensic use of such markers. We then determined the allele and haplotype frequencies, genetic diversity, population differentiation, linkage disequilibrium and ancestral composition in Brazilian urban (healthy individuals from São Paulo, Rio Grande do Sul and Pernambuco), quilombo remnant (Mimbó, Sítio Velho and Gaucinha in the State of Piauí) and Amerindian (Tikúna, Baníwa and Kashináwa) population samples by the analysis of four intragenic microsatellites (IVS 1, IVS 13, IVS 22, IVS 25.3), located on F8 introns, and one extragenic (IKBKG ). When appropriated, the analysis included a group of hemophilic patients. DNA polymorphisms were detected by PCR, PAGE and silver nitrate staining. Statistical analysis was implemented by programs already considered in routine use. Diversity parameters showed differences among the populational samples analyzed. Such regional differences in allele frequencies must be taken into account when conduct the indirect diagnosis of Hemophilia A. Except for IKBKG, all other microsatellites showed high rates of heterozygosity. Using these markers, the diagnosis was possible in 10 of the 11 families analyzed. The microsatellites IVS 22, IVS 1, IVS 13, IVS 25.3 and IKBKG were informative in 63.6% (7 / 11), 54.5% (6 / 11), 54.5% (6 / 11), 45.5% (5 / 11 ) and 18.2% (2 / 11) of the cases, respectively, demonstrating the effectiveness of the use of these microsatellites in prenatal diagnosis and on carrier identification in the Brazilian population.

O fator VIII da coagulação é utilizado para o tratamento da hemofilia A e pode ser obtido a partir de concentrados do plasma humano ou na sua forma recombinante (rFVIII). Nosso laboratório tem explorado uma alternativa mais eficiente para a produção do rFVIII em células de mamíferos, utilizando um variante artificial do rFVIII humano (rFVIII-lab). O objetivo principal deste trabalho foi avaliar a imunogenicidade do rFVIII-lab utilizando camundongos modelo da hemofilia A, tendo como objetivos experimentais a purificação, caracterização de atividade funcional in vivo e caracterização de imunogenicidade do rFVIII-lab comparada a produtos de referência, um derivado de plasma e outro recombinante. Os resultados indicam que o perfil de imunogenicidade observado para o rFVIII-lab foi menos intenso e a atividade funcional observada foi similar quando comparado aos produtos de referência. A expectativa é que o presente estudo contribua para o estabelecimento de uma plataforma de produção do rFVIII no país visando o tratamento dos pacientes hemofílicos brasileiros. / Factor VIII (FVIII) replacement therapy employing either FVIII concentrates from blood plasma or recombinant FVIII is the standard of care for management of hemophilia A. Our group has been exploring a more efficient alternative for recombinant FVIII production in mammalian cells employing an engineered artificial variant of the protein (rFVIII-lab). The main objective of this study was to evaluate the immunogenicity of the rFVIII-lab using a murine model of hemophilia A and the specific experimental objectives were to purify, evaluate the in vivo functional activity and the immunogenicity of rFVIII-lab compared to plasma derived and recombinant reference products. Data revealed reduced immunogenicity of rFVIII-lab whereas functional activity was similar when compared to the reference products. The presented study is expected to contribute to the establishment of a locally production platform for the rFVIII aiming at the treatment of Brazilian hemophilic patients.