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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.
341

Resposta específica aos antígenos da vacina anti-HPV em homens infectados pelo HIV-1 / Specific response to antigens of the anti-HPV vaccine in men infected with HIV-1

Fontes, Adriele Souza 18 August 2014 (has links)
Introdução: A infecção pelo Papiloma Virus Humano (HPV) vem sendo reportada como uma das doenças sexualmente transmissíveis com maior incidência na atualidade, porém a sua prevalência não é bem esclarecida em homens, principalmente devido a baixa presença de sintomas. Além disso, poucos estudos foram realizados nesta população até o momento para verificar a resposta imune pós-vacinação. As hipóteses testadas serão fundamentais para aprofundar o conhecimento da imunopatogênese, da resposta vacinal em pacientes infectados pelo HIV e colaborar no desenho e estratégias de vacinação anti-HPV na população infectada pelo HIV Objetivos: Analisar a resposta específica aos antígenos da vacina anti-HPV em homens infectados pelo HIV. Métodos: Um total de 24 pacientes infectados pelo HIV que preencheram os critérios de inclusão durante o período de coleta foram vacinados pela vacina anti-HPV bivalente em três doses nos períodos: zero, dois e seis meses. Os grupos foram divididos em: Grupo Controle (Cinco indivíduos sadios, com sorologia negativa para HIV); Grupo A (Nove pacientes com CD4 <500 celulas mm³); Grupo B (10 pacientes com CD4 >=500 celulas mm³). Foram realizados ELISA para a detecção de anticorpos Anti-HPV nos momentos pré e pós-vacinação nos grupos estudados; posteriormente realizamos nos mesmos o ensaio de cultura celular para detecção de citocinas (IFN?, IL17, TNF, IL6 e IL10) pela técnica de CBA . Resultados: Obtivemos soroconversão da primeira dose da vacina para o grupo A 55,6%, grupo B 30%, grupo controle 60%; na segunda dose obtivemos para o grupo A 88,8%, grupo B 80%, grupo controle 80%, e por final a terceira dose no grupo A 88,8%, grupo B 90%, grupo controle 100%. A citocina IL 6 (perfil TH2) demonstrou níveis mais elevados, comparados entre os grupos A, B e grupo controle (p<0.001). A partir da 3° dose da vacinação observamos baixos níveis de INF-? (perfil TH1) A e B (p<0.0006). O grupo controle apresentou produção de INF- ? quando comparado com grupos A e B (p<0.001). Conclusão: Os pacientes soropositivos e grupo controle foram respondedores a vacinação anti-HPV. Foi demonstrada uma elevada produção das citocinas entre os grupos sugerindo uma imunomodulação do grupo HIV+. Esse trabalho apresenta informações relevantes que estimulam a realização de novos estudos nessa população, avaliações de reações cruzada da vacina que pode resultar em proteção a outros tipos de HPV não presentes na vacina, além de analisar por mais tempo as titulações no soro desses pacientes. Os dados do nosso estudo podem corroborar para a vacinação nessa população, diminuindo assim o risco de uma infecção, mortalidade e morbidade das doenças causadas pelo HPV em homens. / Introduction: Infection with Human Papilloma Virus (HPV) has been reported as one of the sexually transmitted diseases with a higher incidence nowadys, but its prevalence must be clarified in men, mainly due to low presence of symptoms. Moreover, few studies have been performed in this population until now to verify the immune response post-vaccination. The hypothesis here suggested will be the key for better understanding of the immunopathogenesis, the vaccine´s response in HIV-infected patients and collaborate in the design and strategies of vaccination against HPV in HIV-infected population. Objectives: Analyze the specific response to antigens of HPV vaccine in HIV-infected men. Methods: A total of 24 HIV-infected patients who were in accordance with the inclusion criteria during the data collection period were vaccinated with anti-HPV bivalent vaccine in three period doses: zero, two and six months. The groups were distributed in: Control group (five healthy subjects with negative serology against HIV); Group A (nine subjects with CD4 <500 cells/mm³; Group B (10 subjects with CD4 >500 cells/mm³). ELISA was performed to detect the level of antibodies anti-HPV before and after vaccination in the studied cohort. Postenarly, cells of these groups were submitted in culture to verify citokynes production (IFN?, IL17, TNF, IL6 and IL10) using CBA methodology. Results: We obtained seroconversion after the first dose of anti-HPV vaccine: control group 60%, group A 55,6% and group B 30%. In the second dose: control group 80%, group A 88,8% and Group B 80%. And at last, the third dose: Control Group 100%, Group A 88,8% and group B 90%. IL 6 citokyne (TH2 response) was detected in higher level when compared Control, A and B groups (p<0.001). IFN? citokyne (TH1 response) was detect in low level only after the third dose of vaccination, showing relevance between A and B groups (p<0.0006). Additionally, higher IFN? production was detected when compared the control with A and B groups (p<0.001). Conclusion: HIV patients and controls (HIV-) were responders to anti-HPV vaccination. It was clear that an elevated cytokine production was detected between groups, suggesting immunomodulation of HIV + group. This work suggests relevant information that challenge: new studies in this population, verification of cross-reactions of the vaccine resulting in protection of other HPV types not present in this vaccine, and analyze for longer period the titers of anti-HPV antibodies in these patients. All together, our data can corroborate for vaccination in this population, thus decreasing the risk of infection, mortality and morbidity of the disease caused by HPV in men.
342

DNA Vaccines Against HIV-1: Augmenting Immunogenicity of gp120

Farfan Arribas, Diego Jose 07 January 2002 (has links)
There is currently no protective vaccine against HIV. It is known that a high mutation rate and the existence of many subspecies or clades generated by point mutations or recombination events, are at least partly responsible for the ability of the virus to escape immune responses elicited by classical vaccines. Protein subunit vaccines may not be effective due to this pronounced viral mutability. An immune evasion mechanism has been postulated in which variable domains occlude conserved epitopes crucial for infectivity. The use of DNA vaccines appeared as a favorable approach. Here, a DNA vaccine approach is presented in which the DNA constructs have been engineered to circumvent the aforementioned problems by 1) introducing elements to enhance expression, such as a heterologous promoter, a heterologous signal sequence and intron sequences, 2) by optimizing codon usage, and 3) by vaccinating with antigens that have a modified glycosylation pattern which will make them more immunogenic. The results indicated that deglycosylation of different clades of gp120 did not affect the protein conformation, and 'in vitro' expression levels were good. Antigen codon optimization dramatically increased antibody production. In the animals vaccinated with non-codon-optimized constructs, the presence of an intron and a heterologous signal sequence was required to achieve a good antibody response. Therefore, antigen engineering is required to obtain a powerful immune response against HIV-1 gp120.
343

Efetividade da vacina conjugada contra o meningococo C em menores de dois anos / Effectiveness of conjugate vaccine against meningococcus C in under two years

Conde, Mônica Tilli Reis Pessôa 30 October 2014 (has links)
Objetivo: Estimar o impacto da vacina conjugada contra o meningococo C (VCMC), na incidência e mortalidade, nas coortes de nascidos com e sem indicação de vacinação, no município de São Paulo (MSP); e estimar a efetividade direta da VCMC segundo esquema do Programa Nacional de Imunização. Métodos: O impacto foi avaliado por estudo descritivo, abrangendo casos de doença meningocócica (DM) notificados ao MSP, de 1998 a 2012. A definição de caso é a adotada pelo Ministério da Saúde. Descreveu-se o comportamento da DM no MSP para todo período e analisou-se a tendência da incidência e mortalidade da DM global e por faixa etária de 2008 a 2012, utilizando o modelo de Poisson. O impacto da VCMC foi analisado por meio das razões de taxas de incidência e mortalidade nos períodos anterior e posterior a introdução da VCMC. Estimou-se a fração prevenida na população (FPP) para mensurar o impacto, comparando-se taxas de incidência e mortalidade globais da DM, por faixa etária e sorogrupo C, de 2012 com as de 2009. Para estimativa da efetividade da VCMC utilizou-se estudo de caso-controle de base populacional, com quatro controles para cada caso, pareado pela área de residência dos casos. Casos e controles foram selecionados entre nascidos a partir de janeiro/2009. Casos eram aqueles com DM pelo sorogrupo C confirmado por cultura e/ou reação em cadeia de polimerase em tempo real, de 2011 a 2013, internados em hospitais do MSP, notificados à vigilância do município. Controles foram selecionados entre crianças residentes na vizinhança dos casos, sem história de DM. A efetividade da vacina foi estimada pela fórmula (1-odds ratio para vacinação). As odds ratios (OR) não ajustadas e ajustadas e respectivos intervalos de confiança (IC95 por cento ) foram estimados por regressão 11 logística condicional múltipla. A associação entre ser vacinado com VCMC e a variável dependente, DM pelo sorogrupo C, foi mensurada pela estimativa da OR após ajuste para potenciais confundidores. Resultados: O impacto da VCMC na incidência da DM por todos os sorogrupos, mensurado pela FPP foi de 62,7 por cento , 69,6 por cento e 61,4 por cento para, respectivamente menores um, um e dois anos; na DM pelo sorogrupo C de 81,6 por cento e 67,9 por cento para menores de dois anos e de dois a três anos. Houve impacto na taxa de mortalidade global da DM medido pela FPP de 86,2 por cento e 77,8 por cento respectivamente para menores de dois anos e de dois a três anos e na mortalidade da DM pelo sorogrupo C a FPP foi de 84,2 por cento para menores de quatro anos. A efetividade da VCMC foi de 97,7 por cento (IC95 por cento :99,6 por cento -89,6 por cento ) ajustada para idade, número de pessoas no quarto da criança e renda familiar. Conclusões: A estratégia brasileira com a VCMC resultou em elevado impacto nas coortes de nascidos com indicação de vacinação, mais acentuado nas taxas de mortalidade, sugerindo que a vacina confere não só proteção para a doença, mas também para formas mais graves. A VCMC foi altamente efetiva na faixa etária alvo. / Objective: To assess the impact of meningococcal C conjugate vaccine (MCCV), to estimate incidence and mortality rates of meningococcal disease (MD) in birth cohorts recommended and not recommended for vaccination and to measure direct vaccine effectiveness of the National Vaccination Program immunization schedule. Methods: We assessed the impact of MCCV in a descriptive study including cases of MD reported in the city of Sao Paulo, Brazil, from 1998 to 2012. We used the standard case definition recommended by the Brazilian Ministry of Health for MD reporting. We assessed changes in the disease epidemiology in the city for the entire study period and estimated incidence and mortality rates of MD (overall and by age group) from 2008 to 2012 using Poisson regression models. We conducted an impact analysis of MCCV by comparing incidence and mortality rates of MD before and after vaccine introduction. We also estimated the population prevented fraction (PPF) by comparing incidence and mortality rates of MD between 2009 and 2012 in the entire population and by age group and serogroup C. To measure vaccine effectiveness, we carried out a population-based case-control study matched for area of residence with a 4-to-1 ratio of controls to cases. Cases and controls were selected among children born from January 2009. Cases were those children admitted to the citys hospitals who were diagnosed with MD serogroup C (MDC) confirmed by culture and/or real-time polymerase chain reaction and reported to the surveillance system from 2011 to 2013. Controls were selected among children with no history of MD from neighboring areas of cases. We calculated vaccine effectiveness using the formula (1 odds ratio [OR] for 13 vaccination) and estimated crude and adjusted ORs and related 95 per cent confidence intervals (95 per cent CI) by conditional multiple logistic regression. We assessed the association between MCCV vaccination and MDC the dependent variable by estimating OR after adjustment for the potential confounders. Results: There was an impact of MCCV on the incidence of MD in all serogroups, the PPF among children under age one, age one, and age two were 62.7 per cent , 69.6 per cent , and 61.4 per cent , respectively; and in serogroup C, the PPF in children under age two and age two to three were 81.6 per cent and 67.9 per cent . There was also an impact on the overall mortality rate of MD, the PPF in children under age two and age two to three were 86.2 per cent and 77.8 per cent ; and on mortality of MDC, the PPF was 84.2 per cent in children under age four. MCCV effectiveness in children was 97.7 per cent (95 per cent CI 99.6 per cent 89.6 per cent ) after adjusting for age, number of persons per room, and household income. Conclusions: The MCCV strategy implemented in Brazil had a high impact on birth cohorts recommended for vaccination. This impact was more pronounced on mortality rates, which suggests that, in addition to preventing disease, MCCV can prevent more severe forms of MD. MCCV proved highly effective in the age groups targeted.
344

Next generation approaches to polysaccharide preparation for Burkholderia pseudomallei vaccine development

Baldwin, Victoria Mae January 2016 (has links)
Burkholderia pseudomallei is the aetiological agent of melioidosis and a potential bioterror threat. Infections are difficult to treat due to extensive antibiotic resistance and there is no prophylactic vaccine available. Studies have shown that the capsular polysaccharide (CPS) of B. pseudomallei is a virulence factor, immunogen and candidate antigen for a glycoconjugate vaccine. However, polysaccharides are complex to synthesise. One approach is to genetically engineer Escherichia coli to express the CPS; however, previous attempts at cloning the CPS coding locus from B. pseudomallei into E. coli were unsuccessful. This project proposes to clone only the essential genes from B. pseudomallei and to use native E. coli mechanisms to complete CPS synthesis. This would contribute to development of a new platform for the expression of any bespoke polysaccharide in E. coli. Six biosynthetic genes for the nucleotide sugar precursor were successfully expressed in E. coli. The structure of the precursor was verified by mass spectrometry. Precursor synthesis was also performed in an in vitro microfluidics system. This minimised the quantity of substrates and enzymes required, in preparation for the characterisation of glycosyltransferases required for CPS assembly. A novel assay for characterising glycosyltransferase activity was also developed, as current available options are prohibitively expensive and require significant quantities of glycosyltransferase which are difficult to purify. Finally, plasmids for the expression of additional glycosyltransferases to link the nascent B. pseudomallei CPS to truncated polysaccharides in E. coli were constructed. The aim of this project was to contribute to the development of a platform for the expression of bespoke polysaccharides in E. coli. The CPS of B. pseudomallei was chosen as the model polysaccharide as it has a simple structure and its manufacture is desirable for use in a vaccine against melioidosis.
345

Cellular immune responses of cattle to Escherichia coli O157:H7

Corbishley, Alexander January 2015 (has links)
Enterohaemorrhagic Escherichia coli O157:H7 causes haemorrhagic diarrhoea and potentially fatal renal failure in humans. Ruminants are considered to be the primary reservoir for human infection. Vaccines that reduce shedding in cattle are only partially protective and their underlying protective mechanisms are unknown. Studies investigating the response of cattle to colonisation generally focus on humoral immunity, leaving the role of cellular immunity unclear. To inform future vaccine development, the cellular immune response of cattle during EHEC O157:H7 colonisation was examined. Calves were challenged with either a phage type (PT) 21/28 strain possessing the Shiga toxin (Stx) 2a and Stx2c genes or a PT32 strain possessing the Stx2c gene only. T-helper cell associated transcripts at the terminal rectum were analysed by reverse transcriptase quantitative PCR (RT-qPCR). Induction of interferon (IFN)γ and T-bet was observed, with peak expression of both genes at 7 days in PT32 challenged calves, whilst up regulation was delayed, peaking at 21 days in PT21/28 challenged calves. Cells isolated from gastro-intestinal lymph nodes demonstrated antigen-specific proliferation and IFNγ release in response to type III secreted proteins (T3SPs); however responsiveness was suppressed in cells isolated from PT32 challenged calves. Lymph node cells showed increased expression of the proliferation marker Ki67 in CD4+ T cells from PT21/28, NK cells from PT32 and CD8+ and γδ T cells from both PT21/28 and PT32 challenged calves following ex vivo stimulation with T3SPs. Epitope mapping of rectal lymph node CD4+ T cell responses to 16 EHEC O157:H7 proteins, identified 20 CD4+ T cell epitopes specific to E. coli. The highly conserved N-terminal region of Intimin, including the signal peptide, was consistently recognised by mucosal CD4+ T cell populations from multiple animals of different major histocompatibility complex (MHC) class II haplotypes. Studies investigating the impact of secreted bacterial proteins on bovine peripheral blood mononuclear cells (PBMC) identified the ability of these proteins to cleave the surface molecule CD8 and that this phenotype was dependent on the ler virulence regulator but not the type III secretory system (T3SS) machinery. This effect was also observed in murine and ovine, but not human lymphocytes. Preliminary in vitro experiments suggest that this activity may reduce the efficiency of CD8+ T cell killing. This study demonstrates that cattle mount cellular immune responses during colonisation with EHEC O157:H7, the temporality of which is strain dependent, with further evidence of strain-specific immunomodulation.
346

Analýza přístupu rodičů k problematice očkování dětí v České republice, na příkladu očkování proti tuberkuloze / Analysis of the parents to approach the issue of vaccination of children in the Czech Republic, on the example of vaccination against tuberculosis

Kremličková, Jitka January 2012 (has links)
Dissertation is about the problems with vaccination of children, whose part is also the inoculation against tuberculosis. The objective is the analysis of opinions and approaches of parents toward the problems with vaccination of children in Czech Republic and to discover the level of their knowledge about tuberculosis disease and about vaccination against it. To get the information needed, the anonymous questionary has been used. In the first part we will familiarize ourselves with the main terms from the area of vaccination and also about tuberculosis's basic data. The second part includes presentation of data collected, which are sorted into the bars and graphs. It includes also the calculation of coefficient of benefit for area vaccination against tuberculosis. In the conclusion of work is the summary of collected data and their rating
347

Desenvolvimento de antígeno vacinal para Staphylococcus spp na prevenção da piodermite canina / Development of vaccinal antigen to Staphylococcus spp in the canine pyoderma prevention

Mary Ellen Matiole 28 August 2014 (has links)
A piodermite bacteriana afeta cães de todas as idades, podendo ser recorrente por toda a vida. O principal agente etiológico é o Staphylococcus pseudintermedius, que é um micro-organismo saprófita da pele, agindo como oportunista frente a alguma fragilidade na barreira imunológica. A imunização dos cães através de uma vacina eficaz tem sido um desafio, pois a vacina comercial atualmente utilizada em clínicas veterinárias é de uso terapêutico e não tem caráter preventivo. Um dos problemas da vacina de uso terapêutico para piodermite é a dependência de um bom diagnóstico diferencial em relação a outras doenças de pele ou sistêmicas que tem como sequelas a erupção cutânea. Os animais que recebem a vacina terapêutica e não a preventiva são os que já apresentam problemas de pele reincidentes e são tratados concomitantemente com antibióticos. O objetivo do presente trabalho é desenvolver um antígeno vacinal com possibilidade de aplicação por via intradérmica de modo a tratar preventivamente a piodermite canina causada por Staphylococcus spp:. A via de administração intradérmica tem como finalidade estimular uma resposta imune sistêmica, principalmente por ativação das células dendríticas da derme, de modo a estimular estas células apresentadoras de antígeno no local onde ocorrem as infecções piodérmicas. Os resultados apresentados neste trabalho demonstraram que a inoculação intradérmica foram estatisticamente igual, quando comparada com a inoculação intraperitoneal, no que se refere à inibição por anticorpos: da atividade hemolítica, da atividade da catalase, da atividade da coagulase e da atividade citotóxica, bem como na reação antígeno-anticorpo determinado por ensaio imunoenzimático. Este trabalho também demonstra que a melhor formulação do antígeno estafilocóccico foi preparado a partir de sobrenadante de cultura diafiltrado por filtração tangencial com \"cut off\" de 5.000 Da. Outras preparações utilizando somente células bacterianas ou associação de sobrenadante com células bacterianas, apesar de produzirem antigenicidade, apresentaram títulos inferiores do que quando empregado somente sobrenadante de cultura diafiltrado. / The bacterial pyoderma affects dogs of all ages and can be recurrent for a lifetime. The main etiologic agent is Staphylococcus pseudintermedius, which is a saprophytic organism of the skin, acting as an opportunistic opposite to some weakness in the immune barrier. The immunization of dogs through an effective vaccine has been a challenge, since currently it has been used commercially in veterinary clinics is therapeutic and has a preventive character. One of the problems of the therapeutic use of the vaccine for pyoderma is dependent on a good differential diagnosis in relation to other skin diseases or systemic consequences which is the rash, so treatment often does not reach its goal. Animals receiving this vaccine are those who already have skin problems again and are receiving concomitant antibiotics. The objective of this study is to develop a vaccine antigen with the possibility of implementing a preventive treatment for canine pyoderma caused by Staphylococcus spp: through pre-clinical studies, for use in young and adults, preferably before they develop any type of skin disorder primary or secondary. The administration route is intradermal, stimulating an immune response primarily by dendritic cells to become a barrier to microorganisms, as well as systemic, by the production of antibodies, to last for at least one year until needed in the body booster vaccination. The results presented here demonstrated that the intradermal inoculation was statistically equivalent when compared to intraperitoneal inoculation with regard to inhibition by antibody: of the hemolytic activity, catalase activity, the coagulase activity and cytotoxic activity, as well as antigen-antibody reaction determined by enzyme immunoassay. This work also demonstrates that the best estafilococcico antigen formulation was prepared from the culture supernatant diafiltered by tangential filtration with \"cut off\" of 5,000 Da. Other preparations using only the bacterial cells or the association of supernatant with bacterial cells, although producing antigenicity, showed lower titles than when used dialyzed culture supernatant alone.
348

Avaliação de adjuvantes como estratégia para aumentar a produção da vacina influenza no Instituto Butantan / Adjuvants as strategy to increase influenza vaccine production

Fabio Alessandro de Freitas 20 March 2015 (has links)
Influenza, também conhecida como gripe, é uma doença infecciosa viral que acomete um grande número de indivíduos anualmente, sendo responsável por um elevado número de internações e óbitos. O agente etiológico é o Myxovirus influenzae, vírus envelopado, de RNA de fita simples e polaridade negativa. A vacinação é a forma mais eficaz de se prevenir a infecção pelo vírus, no entanto, a capacidade produtiva dessa vacina não é suficiente para a vacinação da totalidade da população mundial, principalmente em casos de pandemia. Esse projeto teve por objetivo desenvolver uma vacina influenza (fragmentada e inativada) adjuvada, visando aumentar a capacidade produtiva dessa vacina no Instituto Butantan, que hoje é estimada em aproximadamente 40 milhões de doses por campanha. A utilização de adjuvantes na formulação da vacina influenza é capaz de produzir a mesma resposta imunológica protetora contra esse vírus, utilizando uma quantidade menor dos antígenos vacinais, aumentando a capacidade de produção da vacina em até quatro vezes. Foram estudadas 23 formulações adjuvantes utilizando o esqualeno como referência (formulação similar ao MF59®, adjuvante desenvolvido pela Novartis), vitaminas lipossolúveis (vitaminas A, D e E), vitamina B2 (vitamina hidrossolúvel), MPLA (monofosforil lipídio A, produzido pelo Instituto Butantan como subproduto da vacina pertussis low) e gel de hidróxido de alumínio. Para tanto, foram avaliadas a resposta imune conferida a camundongos BALB/c após imunização com diferentes formulações de vacina influenza (fragmentada e inativada) adjuvada e a existência, ou não, de toxicidade induzida pelas formulações vacinais estudadas. As formulações vacinais mais promissoras farão parte das formulações candidatas para realizações de ensaios clínicos. Os animais foram imunizados por via intraperitoneal com as formulações vacinais e foram colhidas amostras de sangue para ensaios sorológicos (inibição de hemaglutinação e ELISA) e células esplênicas para avaliação celular (dosagem de citocinas por citometria de fluxo: IL-2, IL-4, IL-6, IL-10, IL-17 TNF-&#945; e INF-&#947;). Além disso, em um dos experimentos avaliou-se a formação de memória imunológica contra influenza, parâmetro importante em se pensando em uma vacina. Os três primeiros experimentos foram uma triagem a partir da qual selecionaram-se as melhores formulações que foram testadas no último experimento. Nele foram avaliados além da indução de resposta imune a toxicidade e a memória imunológica. Todas as 23 formulações estudadas induziram resposta minimamente protetora nos animais, com exceção da formulação contendo apenas MPLA como adjuvante. As formulações que se mostraram mais promissoras continham além do gel de AI(OH)3 MPLA de B. pertussis ou vitamina B2. Isso sem considerar o tocoferol (vitamina E), que embora tenha apresentado bons resultados acabou preterido em decorrência de sua potencial relação com casos de narcolepsia descritos na literatura. O teste de memória foi capaz de demonstrar que essas formulações produzem resposta de memória imunológica duradoura. Assim, tem-se resultados promissores para novos estudos pré-clínicos e clínicos com a vacina influenza (fragmentada e inativada) sazonal (trivalente). / Influenza, also known as flu, is a viral infectious disease that infects a large number of people annually, being responsible by large morbidity and mortality rates. The etiologic agent is the Myxovirus influenzae, an enveloped virus with single-stranded RNA and negative polarity. Vaccination is the best way to prevent the virus infection; however, the production capacity of this vaccine is not sufficient to vaccinate the entire world population, especially in cases of pandemics. This project aimed to develop an adjuvanted influenza vaccine (split and inactivated), increasing the productive capacity of this vaccine in Instituto Butantan, which is estimated in approximately 40 million of doses by campaign. Influenza vaccines formulated with adjuvants can produce the same protective immunological response against the virus using less amount of antigen increasing the production capacity of this vaccine up to four times. Twenty-three adjuvants containing fat-soluble vitamins (vitamins A, D and E), vitamin B2 (water-soluble vitamin), MPLA (monophosphoryl lipid A, produced by Instituto Butantan as a byproduct of pertussis low vaccine production) and aluminum hydroxide gel were studied. An adjuvant similar to MF59® (Novartis adjuvant) containing squalene was used as control. The immune response elicited in BALB/c mice after immunization with the different formulations of the influenza vaccine and the existence or not of toxicity induced by the vaccines formulations were studied. The most promising formulation will be part of the candidate formulations of clinicai trials. The animais received the vaccine formulations intraperitoneally and at specific days blood samples were taken to serological tests (hemagglutination inhibition and ELISA). At the end, they were euthanized to collect the spleens and splenic cells were cultivated to evaluate cytokines by flow cytometry: IL-2, IL-4, IL-6, IL-10, IL-17 TNF-&#945; and INF-&#947;. Furthermore, in one experiment the immunological memory against influenza was evaluated, an important parameter to vaccines. The most promising formulations contained besides to alum either B. pertussis MPLA or B2 vitamin. Tocopherol (vitamin E) presented good results too, however it has a potential relationship with reported cases of narcolepsy. The memory test was able to demonstrate that these formulations induced long lasting immune memory response. Thus, these are promising results for new pre-clinical and clinical trials with seasonal trivalent influenza vaccine (split and inactivated).
349

Avaliação do uso de óleos de origem vegetal para formulação de adjuvantes vacinais / Assessment of the use of vegetable oils for formulation of vaccine adjuvant.

Marnen Almeida Carvalho 27 July 2012 (has links)
Os óleos vegetais são matérias primas de fontes renováveis. São metabolizáveis, biodegradáveis, de fácil disponibilidade e baixo custo. A necessidade de adjuvantes vacinais seguros e que possam modular a resposta imunológica Th1/Th2, favorece a busca por novas substâncias que assim se comportem. Este trabalho tem o objetivo de avaliar e identificar óleo vegetal capaz de mimetizar ação adjuvante dos óleos minerais comercialmente usados e modular a resposta imune. Foram realizados testes de toxicidade aguda in vivo, testes de formação de emulsões, de estabilidade, de qualidade e, por fim, de imunogenicidade com formulações com o vírus rábico. Algumas formulações derivadas dos óleos de girassol, canola e buriti se mostraram não tóxicas, estáveis e de boa qualidade. Os grupos de camundongos inoculados com estas formulações obtiveram respostas imunológicas que apoiam sua capacidade adjuvante, não diferenciando significativamente (p<0,05) dos resultados do óleo mineral comercial. Concluiu-se que é possível elaborar emulsões estáveis não tóxicas a partir de óleos vegetais para sua utilização como veículos e adjuvantes vacinais. Formulações vacinais em forma de emulsões de óleos vegetais, compostas na sua maior parte pelos óleos de girassol e de canola possuem potência e atividade adjuvante semelhantes e tão eficientes quanto aos do óleo mineral. Os óleos vegetais devem estar em seu estado bruto ou semirrefinado, sem a adição de antioxidantes e conservantes. Por último, parece haver uma tendência de equilíbrio de resposta Th1/Th2 para as formulações com óleos vegetais. / Vegetable oils are renewable raw materials. These substances are metabolizable, biodegradable, of easy availability and low cost. The need for safe vaccine adjuvants that can modulate the Th1/Th2 immune response drives the search for new substances with similar behavior. This study aims to evaluate and identify a vegetable oil able to mimic the adjuvant action of the mineral oils used commercially, and modulate the immune response. There were performed tests of in vivo acute toxicity, emulsion formation, stability, quality and immunogenicity with formulations with rabies virus. Some formulations derived from the sunflower, canola and buriti oils proved to be non-toxic, stable and of good quality. Groups of mice inoculated with these formulations had immune responses supporting their adjuvant capacity, not differing significantly (p <0.05) from the results of the commercial mineral oil. It was concluded that it is possible to prepare stable non-toxic emulsions from vegetable oils to be used as vaccine adjuvants and vehicles. Vaccine formulations as emulsions from vegetable oil, composed mostly by the oils of sunflower and canola had adjuvant activity and potency similar to and as effective as the mineral oil. The vegetable oils should be in its raw state or semi refined, without the addition of antioxidants and preservatives. Finally, there seems to be a tendency to balance Th1/Th2 response by formulations with vegetable oils.
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Poder imunogênico de bacterina experimental anti leptospirose canina: ensaio em hamsters desafiados com estirpes de leptospiras dos sorovares Copenhageni e Canicola isoladas no Brasil / Immunogenic power of an experimental canine antileptospirosis bacterin: assay in hamsters challenged with strains of leptospiras serovars Copenhageni and Canicola isolated in Brazil

Mucciolo, Giancarlo Balotim 20 September 2010 (has links)
A proteção induzida por uma vacina comercial anti-leptospirose importada, bivalente produzida com estirpes de referência dos sorovares Icterohaemorrhagiae e Canicola, foi comparada a promovida por uma bacterina experimental, bivalente produzida com as estirpes autóctones M64/06 e LO-4, respectivamente dos sorovares Copenhageni e Canicola, isoladas no Brasil e tipificadas com anticorpos monoclonais produzidos pelo Royal Tropical Institut, Laboratório de Referência da Organização Mundial de Saúde. O ensaio foi conduzido pelo teste de potência com desafio em hamsters. A vacina experimental, bivalente foi inativada com fenol a 37%, ajustada para concentração de 108 leptospiras por mL, por sorovar e produzida nas versões com e sem adjuvante hidróxido de alumínio a 0,15%. Os hamsters foram imunizados com 0,25 mL de vacina, via subcutânea em duas aplicações com 15 dias de intervalo. Os desafios foram efetuados com as estirpes LO4 (Canicola) ou L1-130 (Copenhageni) isoladas no Brasil, respectivamente nas diluições de 10-3 e 10-1 no volume de 0,5 mL via intraperitoneal por animal, 15 dias após a última dose da vacina. A estirpe de desafio do sorovar Copenhageni foi caracterizada, por anticorpos monoclonais, como idêntica a M64/06 e foi escolhida devido a apresentar melhor regularidade em termos de patogenicidade para os hamsters. Decorridos 20 dias do desafio os hamsters sobreviventes foram eutanasiados em câmara de CO2, necropsiados e nos seus rins foi efetuada a pesquisa do estado de portador de leptospiras por cultivo em meio de Fletcher. Nos desafios efetuados com a estirpe autóctone, L1-130 do sorovar Copenhageni foi obtida a proteção contra a doença clínica em oito de dez animais, para as duas vacinas experimentais, no entanto, entre os sobreviventes, houve portadores renais de leptospiras, em maior número para a vacina sem adjuvante (n=5), quando comparado a vacina acrescida de Al(OH)3, (n=3); para a vacina comercial a proteção foi total, tanto contra a doença como quanto a infecção não havendo qualquer morte por leptospirose e todos os cultivos renais dos sobreviventes foram negativos para leptospiras. Nos desafios efetuados com a estirpe autóctone, LO4 do sorovar Canicola, a proteção conferida pelas três vacinas ensaiadas foi total, não havendo mortes por leptospirose e todos os sobreviventes apresentaram resultados negativos para leptospiras nos cultivos de tecido renal. Os números de DL50 empregadas nos inóculos de desafio foram superiores a 10.000, para os dois sorovares ensaiados, pois na titulação dos inóculos morreram mais do que 50% dos animais até a última diluição testada. Foi, portanto, demonstrado a existência de proteção cruzada entre os sorovares Copenhageni e Icterohaemorrhagiae e que a bacterina importada foi capaz de induzir proteção contra a doença e contra a infecção para estirpes de leptospiras autóctones dos sorovares Canicola e Copenhageni isoladas no Brasil. Nos desafios efetuados com o sorovar Canicola a vacina experimental induziu proteção contra a doença e contra a infecção, mas nos que empregaram o sorovar Copenhageni houve proteção apenas contra a doença, constatando-se menor número de portadores renais de leptospiras entre os animais imunizados com a bacterina experimental acrescida do adjuvante de hidróxido de alumínio. / The protection induced by an imported commercial bivalent anti-leptospirosis vaccine produced with the reference strain of the serovars Icterohaemorrhagiae and Canicola was compared to one promoted by an experimental, bivalent bacterial vaccine produced with the indigenous strains M64/06 and LO-4, respectively of the serovars Copenhageni and Canicola isolated in Brazil and typified with monoclonal antibodies produced by the Royal Tropical Institut, Reference Laboratory of the World Health Organization. The assay was conducted by using the potency test with challenge in hamsters. The experimental bivalent vaccine was inactivated with 37% phenol and adjusted at a concentration of 108 leptospires/mL, for each serovar and produced in the versions with and without adjuvant (0.15% aluminium hydroxide). The hamsters were immunized by 0.25 mL of vaccine, by subcutaneous route in two applications with 15 days of interval. Fifteen days after receiving the last dose of the vaccine, the challenges were performed by employing the strains LO4 (Canicola) or L1-130 (Copenhageni), which were isolated in Brazil, respectively at the dilution of 10-3 and 10-1, in the volume of 0.5 mL/each animal by the intraperitoneal route. The challenge strain serovar Copenhageni has been characterized as identical to M64/06 strain by means of monoclonal antibodies and it was chosen due to its better regularity in terms of pathogenicity determined in hamsters. After 20 days of the challenge, the surviving hamsters were sacrificed in CO2 chamber, submitted to necropsy and the kidneys were examined to test the carrier state of leptospires by cultivation in Fletcher\'s medium. In the challenges effectuated with the indigenous strain, L1-130 of the serovar Copenhageni the protection was obtained against the clinical disease in eight of ten animals, for two experimental vaccines, however, among the survivors, there were renal carriers of leptospires, in higher number for the vaccine without containing the adjuvant (n=5), when compared to the one added with Al (OH) (n=3). For the commercial vaccine, the protection was total both against the disease and as for infection, when no death was found in consequence of leptospirosis and all the renal cultures of the survivors were negative for leptospires. In the challenges performed with the indigenous strain LO4 of the serovar Canicola, the protection conferred by the three vaccines tested was total, without observing any deaths due to leptospirosis and all the survivors presented negative culturing results for leptospires in the renal tissue. The challenge doses of the inocula were superior to 10,000 LD50, for the two serovars tested, since in the titration of the inocula have died more than 50 % of the animals up to the last tested dilution. So, the crossed protection existing between the serovars Copenhageni and Icterohaemorrhagiae was demonstrated and that the imported bacterial vaccine was able to induce protection against the disease and against the infection for the native strains of leptospires serovars Canicola and Copenhageni isolated in Brazil. In the challenges effectuated with the serovar Canicola, the experimental vaccine induced protection against the disease and against the infection, but in vaccine employing the serovar Copenhageni, protection was found only against the disease, when less number of renal carriers of leptospires was observed among the animals immunized with the experimental vaccine added with the aluminium hydroxide adjuvant.

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