• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 13
  • 4
  • 2
  • Tagged with
  • 21
  • 21
  • 11
  • 6
  • 6
  • 6
  • 5
  • 5
  • 5
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 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

Development of nanoparticle based nicotine vaccines for smoking cessation

Hu, Yun 15 June 2015 (has links)
Cigarette smoking is prevalent worldwide and has consistently been the top preventable cause of many serious diseases., which result in huge mortality, morbidity, and economic loss, in recent decades. In recent years, nicotine vaccines that can induce production of nicotine specific antibodies in human have emerged as a promising medicine to treat tobacco addiction. In the past decade, there have been numerous nicotine vaccine candidates evaluated in human clinical trials, including NicVaxNicVAX®, TA-NICTA-NIC®, Nic002NIC002®, NiccineNiccine®, and SEL-068SEL-068®. . However, traditional nicotine vaccine designs haves many disadvantages, including low immunogenicity, low specificity, difficulty in integration of molecular adjuvants, and short immune response persistence. To overcome the above limitations, in this study, various nanoparticle-based vaccine delivery systemsvaccine componentss have been developed and evaluated as potential delivery vehicles for vaccines against nicotine addiction. Firstly, a nicotine vaccine was synthesized by conjugating bovine serum albumin (BSA)-nicotine complex to the surface of nano-sized cationic liposome. Significantly higher anti-nicotine antibody titer was achieved in mice by liposome delivered nicotine vaccine compared with nicotine-BSA vaccine. Secondly, a novel nanoparticle (NP)-based delivery platform was constructed by incorporating a negatively charged nanohorn into cationic liposome to improve the stability of liposome and reduce nanoparticle flocculation. Subsequently, nicotine vaccine was constructed by conjugating nicotine-BSA complex to the surface of the nanohorn supported liposome (NsL). Marked improvement in stability in vitro and significant increase in titer of anti-nicotine antibodies were detected in nanohorn supported liposome ( NsL) delivered vaccine than liposome delivered vaccine. In addition, NsL nicotine vaccine exhibited good safety in mice after multiple injections. Thirdly, lipid- poly(lactic-co-glycolic acid) (PLGA) hybrid NPs were constructed as vaccine delivery system. due to the fact that nanohorn is not currently approved for clinical use, we substituted the nanohorn with poly(lactic-co-glycolic acid) (PLGA) nanoparticles and constructed PLGA-lipid hybrid nanoparticles. Preliminary results showed that PLGA-lipid hybrid NPs nanoparticles exhibited improved stability, better controlled release of antigens, as well as enhanced uptake by dendritic cell (DC). A lipid-PLGA hybrid NPnanoparticle was also developed that was structurally responsive to low pH challenge. The lipid shell of the hybrid nanoparticle was rapidly disintegrated under a low pH challenge, which resembles the acidic environment of endosomes in DCsdendritic cells. The hybrid NPs exhibited minimal antigen release in human serum at physiological pH, but a faster release of antigen from this NP compared to non-pH sensitive NPs was observed in DC. In the final study, hybrid NPnanoparticles with various cholesterol concentrations were constructed. Slower and more controlled release of antigens in both human serum and phosphate buffered saline were detected in nanoparticles with higher cholesterol content. However, nanoparticles containing higher cholesterol showed poorer stability due to increase fusion among NPnanoparticles. It was later found that PEGylation of NPs can effectively minimize fusion caused size increase after long term storage, leading to improved cellular uptake. The findings from this study on the nanohorn-lipids based nicotine vaccine as well as lipid-PLGA hybrid NPs may provide solid basis for future development of lipid-PLGA based nicotine vaccine. / Ph. D.
2

Efeitos adjuvantes de derivados da toxina termo-lábil de Escherichia coli (LTI) na resposta de anticorpos específicos voltados para o domínio III da glicoproteína e do vírus dengue tipo 2 (DENV2). / Adjuvant effects of Escherichia coli thermo-labile toxin (LT1) derivatives in the specific antibody response directed to the E glycoprotein domain III of type 2 dengue virus (DENV2).

Fabris, Denicar Lina Nascimento 15 July 2014 (has links)
As toxinas termo-lábeis (LT) produzidas por linhagens de Escherichia coli enterotoxigênica (ETEC) são adjuvantes com um importante foco em pesquisas acadêmicas e aplicadas, entretanto pouco é conhecido sobre a capacidade desses adjuvantes em induzir diferentes padrões de glicosilação em anticorpos IgG. Desta forma, o objetivo do presente trabalho foi analisar a capacidade dos adjuvantes LT1 e seus derivados atóxicos (LT1-K63 e LT1-B) influenciarem na qualidade da resposta imunológica humoral, particularmente quanto aos perfis de glicosilação dos anticorpos IgG EIII-específicos. A administração das LTs proporcionaram a potencialização da resposta de anticorpos antígeno-específicos, modularam o perfil de subclasses de IgG, melhoraram a capacidade de neutralização viral e induziram diferentes perfis de glicosilação presentes na estrutura dos anticorpos induzidos. Os resultados obtidos demonstram a importância dos adjuvantes no perfil de glicosilação de anticorpos antígeno-específicos e sugerem a influência da glicosilação na funcionalidade desses anticorpos. / The heat-labile toxin (LT) produced by enterotoxigenic Escherichia coli (ETEC) are an important adjuvants to focus on academic and applied research, however little is known about the ability of these adjuvants to induce different patterns of glycosylation in IgG antibodies. Thus, the aim of this study was to analyze the ability of the adjuvants LT1 and its nontoxic derivative (LT1-K63 and LT1-B) influence on the quality of the humoral immune response, particularly regarding the glycosylation profiles of the EIII-specific IgG antibodies. The management of transmission lines provided potentiation response of antigen-specific antibodies modulate the profile of IgG subclasses, improved ability to induce virus neutralizing and different glycosylation profiles of in the antibodies purified IgG. The results demonstrate the importance of adjuvants in glycosylation of antigen-specific antibody profile and suggest the influence of glycosylation on the functionality of these antibodies.
3

Impacto da imunidade prévia nos efeitos adjuvantes da toxina termo-lábil (LT) de Escherichia coli enterotoxigênica. / Impact of previous immunity in the adjuvant effects of enterotoxigenic Escherichia coli heat labile toxin (LT).

Cintra, Mariana de Jesus 29 October 2015 (has links)
As toxinas LT são expressas por linhagens de Escherichia coli enterotoxigênicas e possuem marcantes efeitos adjuvantes. No entanto, não se conhece se a exposição prévia à toxina afeta sua atividade adjuvante durante imunizações subsequentes. Assim, o presente estudo avaliou o impacto da imunidade pré-existente nas propriedades inflamatórias e adjuvantes da LT quando inoculada pela via subcutânea. Como antígeno modelo, empregou-se a proteína NS1 do vírus dengue e duas abordagens experimentais distintas: (i) incubação in vitro de LT com anticorpos anti-LT e com o receptor gangliosídio (GM1) antes da administração em camundongos não imunizados em conjunto com a proteína NS1 do vírus dengue; (ii) imunização com NS1 coadministrada à LT em camundongos previamente expostos à LT. Foram avaliados os efeitos inflamatórios locais e os efeitos adjuvantes por meio da resposta imunológica humoral anti-NS1. Nossos resultados indicam que a imunidade prévia contra a LT não afeta seu potencial inflamatório e atividade adjuvante. Além disto, a exposição ao receptor GM1 reduziu as reações inflamatórias locais sem, no entanto, reduzir os efeitos adjuvantes de LT. / LT toxins are expressed by enterotoxigenic Escherichia coli strains and display strong adjuvant effects. Nonetheless, the impact of preexisting immunity on the on LT adjuvant activities is still unknown. Thus, the present study evaluated the impact of pre-existing immunity in the inflammatory and adjuvant properties of LT after subcutaneous administration. the NS1 of dengue virus was employed as a model antigen and two experimental approaches were evaluated: (i) in vitro incubation of LT with LT-specific antibodies and the ganglyoside receptor (GM1) before administration to naïve mice in combination with NS1; (ii) immunization with NS1 co-administered with LT in mice previously exposed to LT. The local inflammatory effects induced by LT were evaluated as wel as the adjuvant effects by means of NS1-specific humoral response. Our results indicate that the LT pre-existing immunity does not affect the inflammatory and adjuvant activities of the toxin. In addition, exposure to GM1 reduced the local inflammatory reactions without affecting the toxin adjuvant effects.
4

Resposta imune humoral na Leishmaniose Tegumentar humana causada por Leishmania (Viannia) guyanensis no município de Manaus, AM - Brasil

Mota, Karina Camara da 25 November 2008 (has links)
Made available in DSpace on 2015-04-22T22:14:11Z (GMT). No. of bitstreams: 1 DISSERTACAO kARINA.pdf: 1878961 bytes, checksum: f6896d6307a1bc7e9fd5b8e1379c4194 (MD5) Previous issue date: 2008-11-25 / Fundação de Amparo à Pesquisa do Estado do Amazonas / The protozoa of the genus Leishmania has a great diverty of species and are related whith the clinical form of American tegumentary Leishmaniasis (ATL) and Visceral Leishmaniasis (VL) distinguish through the geographical distribuition, the reservoir hosts and the vectors involved in the cycle, with incidence and mortality variation according with the region. Although the clinical variation forms found in patients with ATL the ilness could be grouped in three basics types: cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis (ML) and diffuse cutaneous leishmaniasis. The immune response profile differs in the linfocyte activation of TCD4+ Th1 or Th2. The Th1 and Th2 cells could be identidied through the secreted cytokines, the Th1 linfocytes produced activators cytokines by immunity cells mediated as well as the INFg, INF a, IL-2 and IL-12. Howerver the infection susceptibility is related to Th2 cell response that secreted cytokine IL-4, IL-5, IL-6, IL-10, TGF-B, promoting the antibody response. In the mucosal leishmaniasis has a misture of Th1 and Th2 response profile, before and after treatment, with higt levels of IgA. The leterature shows that there is a positive correlation between the high levels of IgE and the Montenegro reaction, suggesting that these antigens guide the TCD+ response to a Th1 profile. For this one, the levels of immunoglobulins isotypes (IgG, IgM, IgA and IgE) were measured in the serum samples of 36 patients infected with cutaneos and mucosal leishmaniasis caused by Leishmania (Viannia) guyanensis, from the Manaus municipality, Amazonas State, Brazil. The technicals employed were ELISA and Western Blotting. This study showed low levels of IgM and IgG in patients infected with L.(V.) guyanensis by the ELISA method using the OPD substract tht was sinsible to detect the serics immunoglobulins, for this method could not be used as diagnostic but is indicate to follow-up the infection evolution. / Os protozoários do gênero Leishmania, compreendem uma vasta diversidade de espécies e estão relacionados com a forma clínica da leishmaniose (LTALeishmaniose Tegumentar Americana e LV- Leishmaniose Visceral) diferindo quanto a distribuição geográfica, aos hospedeiros e vetores envolvidos, com variações nas taxas de incidência e mortalidade de acordo com a região. Apesar da ampla variedade de formas clínicas encontradas em pacientes com LTA, podemos agrupá-las em três tipos básicos: leishmaniose cutânea (LC), leishmaniose cutâneo-mucosa (LCM) e leishmaniose cutânea difusa (LCD). O perfil da resposta imunológica na leishmaniose cutânea difere na ativação de linfócitos T CD4+ Th1 ou Th2. As células Th1 e Th2 se identificam segundo o perfil de citocinas que elas secretam, os linfócitos Th1 produzem fundamentalmente citocinas ativadoras da imunidade mediada por células tais como o INF-γ, INFa, IL-2 e IL12. Por outro lado, a sucetibilidade à infecção está relacionada à resposta de célula Th2, que secretam citocinas do tipo IL-4, IL-5, IL-6, IL-10, TGF-b, promovendo a resposta de anticorpos. Por outro lado, na leishmaniose mucosa há um mistura de perfil de resposta Th1 e Th2, antes e após tratamento, com altos índices de IgA. Dados de literatura demonstram que existe uma correlação positiva entre altos índices de IgE e a reação de Montenegro, sugerindo que antígenos orientam a resposta T CD4+ para um perfil Th2. Desta forma, buscou-se detectar níveis séricos de isotipos de imunoglobulinas (IgG, IgM, IgA e IgE) em amostras de soros de pacientes infectados com Leishmaniose cutânea e mucosa causada por Leishmania (Viannia) guyanensis, proveniente do município de Manaus, estado do Amazonas, Brasil. A técnica empregada foi o ELISA. Esta técnica utiliza extratos ou frações antigênicas do parasita. Este estudo demonstrou que a técnica sorológica pelo método de ELISA utilizando como substrato OPD é sensível para detectar a presença de imunoglobulinas séricas IgG e IgM em humanos infectados com a Leishmania (Viannia) guyanensis assim como a infecção por esta espécie leva a produção de baixo níveis de IgG e IgM, não devendo ser considerada como método útil no diagnóstico e sim como acompanhamento da evolução da infecção.
5

Impacto da imunidade prévia nos efeitos adjuvantes da toxina termo-lábil (LT) de Escherichia coli enterotoxigênica. / Impact of previous immunity in the adjuvant effects of enterotoxigenic Escherichia coli heat labile toxin (LT).

Mariana de Jesus Cintra 29 October 2015 (has links)
As toxinas LT são expressas por linhagens de Escherichia coli enterotoxigênicas e possuem marcantes efeitos adjuvantes. No entanto, não se conhece se a exposição prévia à toxina afeta sua atividade adjuvante durante imunizações subsequentes. Assim, o presente estudo avaliou o impacto da imunidade pré-existente nas propriedades inflamatórias e adjuvantes da LT quando inoculada pela via subcutânea. Como antígeno modelo, empregou-se a proteína NS1 do vírus dengue e duas abordagens experimentais distintas: (i) incubação in vitro de LT com anticorpos anti-LT e com o receptor gangliosídio (GM1) antes da administração em camundongos não imunizados em conjunto com a proteína NS1 do vírus dengue; (ii) imunização com NS1 coadministrada à LT em camundongos previamente expostos à LT. Foram avaliados os efeitos inflamatórios locais e os efeitos adjuvantes por meio da resposta imunológica humoral anti-NS1. Nossos resultados indicam que a imunidade prévia contra a LT não afeta seu potencial inflamatório e atividade adjuvante. Além disto, a exposição ao receptor GM1 reduziu as reações inflamatórias locais sem, no entanto, reduzir os efeitos adjuvantes de LT. / LT toxins are expressed by enterotoxigenic Escherichia coli strains and display strong adjuvant effects. Nonetheless, the impact of preexisting immunity on the on LT adjuvant activities is still unknown. Thus, the present study evaluated the impact of pre-existing immunity in the inflammatory and adjuvant properties of LT after subcutaneous administration. the NS1 of dengue virus was employed as a model antigen and two experimental approaches were evaluated: (i) in vitro incubation of LT with LT-specific antibodies and the ganglyoside receptor (GM1) before administration to naïve mice in combination with NS1; (ii) immunization with NS1 co-administered with LT in mice previously exposed to LT. The local inflammatory effects induced by LT were evaluated as wel as the adjuvant effects by means of NS1-specific humoral response. Our results indicate that the LT pre-existing immunity does not affect the inflammatory and adjuvant activities of the toxin. In addition, exposure to GM1 reduced the local inflammatory reactions without affecting the toxin adjuvant effects.
6

Resposta humoral de bovinos para os toxóides botulínicos C e D

Curci, Vera Cláudia Lorenzetti Magalhães [UNESP] 19 June 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-06-19Bitstream added on 2014-06-13T18:48:10Z : No. of bitstreams: 1 curci_vclm_dr_jabo.pdf: 208355 bytes, checksum: b31da2026d8809c55818b68c4c8d77b7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foi avaliado pelo teste de ELISA indireto a resposta humoral para as toxinas botulínicas tipos C e D em animais vacinados com quatro diferentes produtos comerciais. Empregou-se duas vacinas bivalentes C e D (vacina 1 e vacina 2) e duas polivalentes contendo ainda os toxóides botulínicos tipos C e D (vacina 3 e vacina 4). Para análise foram realizadas seis colheitas de sangue ao longo do experimento, nos dias 0, 42, 75, 160, 250 e 342 após a vacinação. A imunidade passiva em bezerros até os 90 dias de idade, filhos de mães vacinadas com diferentes toxóides comerciais foram avaliados em 75 bezerros, agrupados de acordo com a vacina utilizada na mãe (B1, B2, B3 e B4). Para análise foram realizadas 3 colheitas de sangue, nos dias 5 (± 2), 45 e 90 dias após o nascimento. A avaliação da resposta humoral de bovinos vacinados em diferentes faixas etárias também foi realizada empregando-se uma vacina antibotulínica bivalente (C e D) comercial. Para análise, 90 bovinos foram divididos em 3 grupos de acordo com a faixa etária; animais com idade inferior a 2 anos, entre 2 e 5 anos e superior a 5 anos. Na avaliação da resposta humoral de animais vacinados com quatro diferentes produtos comerciais, para a toxina tipo C, as vacinas 1, 2, 3 e 4 não apresentaram diferenças significativas aos 42 dias da primeira dose. Aos 75 dias, a vacina 1, foi superior às vacinas 3 e 4, induzindo maior produção de anticorpos nos animais, porém não diferiu da vacina 2. Aos 160 dias houve queda na quantidade de anticorpos em todos os grupos, não havendo mais diferenças significativas entre as quatro vacinas testadas. Para a toxina tipo D, aos 42 dias da vacinação, não houve diferenças significativas entre as vacinas 1, 2 e 4, que apresentaram neste momento, valores superiores a vacina 3. No entanto, quando avaliadas aos 75 dias, a vacina 1 apresentou maior produção de anticorpos, diferindo... / To compare the efficiency of an “in house” ELISA test, standardized to measure antibody C and D from Clostridium botulinum, a survey to analysis four different commercial vaccines was conducted. The vaccines used were two commercial, bivalent botulinum containing subtypes C and D (vaccine 1 and vaccine 2) and other two polyvalent including subtypes C and D. The first trial was blood samples taken at 0, 42, 75, 160, 250 and 342 days after vaccination, whereas the booster was performed at day 42. The second trial, maternal antibodies were also measured taken blood samples from 1-3 months age steers obtained from vaccinated heifers with the same vaccines described above, and divided into four different groups (B1, B2, B3, B4). The blood samples were taken at days 5, 45 and 90 after birth. Third and last trial was humoral response from vaccinated cattle with different age evaluation performed using the commercial Clostridium botulinum vaccine subtype C and D. For this purpose, 90 animals never vaccinated, were divided into 3 groups: 1 - 2 years old; 2 – animals aged between 2 and 5 years old; 3 – animals 5 years old. The blood samples were taken 30 days after vaccination after second dose of the vaccine. From the first trial, no significant difference was observed when subtype C was search in sera from animals at 42 days after vaccination. However, at 75 days after vaccination, vaccine 1 was able to induce higher levels of antibodies when compared to vaccine 3 and 4. The antibody level was declining after 160 days post vaccination. For subtype D antigen, at 42 days after vaccination, no differences could be observed. However, at 75 day after vaccination, higher levels of antibodies were observed from animals vaccinated with vaccine 1. Comparing the bivalent vaccines, these were able to induce higher antibodies levels at 75 days after vaccination (toxoid C). In addition, the same... (Complete abstract click electronic access below)
7

Expressão de antígenos específicos de câncer/testículo em linfomas / Expression of cancer/testis antigens in lymphomas

Inaoka, Riguel Jun [UNIFESP] 25 August 2010 (has links) (PDF)
Made available in DSpace on 2015-07-22T20:50:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-25 / Os antígenos cancer/testículo (CTAs) são considerados promissores alvos para abordagens de imunoterapia em câncer devido à sua alta imunogenicidade e padrão de expressão praticamente restrito a tecidos tumorais (estão também expressos em células germinativas do testículo, placenta e ovário fetal). Apesar do padrão de expressão dos CTAs estar bem estabelecido em carcinomas, pouco se sabe sobre a expressão desses antígenos em neoplasias linfóides como Linfomas de Hodgkin (LH) e Linfomas não-Hodgkin (LNH). Objetivo: Avaliar o potencial desses antígenos específicos tumorais como candidatos à imunoterapia em linfomas, através da análise de expressão protéica dos CTAs e avaliação da resposta imune humoral espontânea contra esses antígenos, correlacionando os achados com os dados clínicos e prognóstico. Métodos: Três blocos de Tissue Microarray (TMA) foram construídos a partir de 38 amostras teciduais de LH clássico e 106 de LNH obtidos nos arquivos do Departamento de Anatomia Patológia da UNIFESP. As lâminas de TMA foram submetidas a um painel de imunohistoquímica para 9 CTAs, a saber: MAGE-A1, MAGE-A3, MAGE-A4, MAGE-A10, CT7, CT10, NY-ESO-1, LAGE e GAGE. A avaliação da imunidade humoral espontânea foi realizada em 97 amostras de soro de pacientes com LNH ao diagnóstico (59 dos quais foram incluídos na casuística do TMA), utilizando-se a técnica de ELISA em um painel mais amplo de CTAs (MAGEA1, MAGE-A3, MAGE-A4, MAGE-A10, NY-ESO-1, CT7, CT10, CT24, CT45, CT46, CT47, CT63, CT83, SSX-1, SSX-2, SSX-4, LAGE-1, GAGE-2, SAGE-1, XAGE-1). Resultados: De forma global, houve baixa expressão de CTAs nas amostras analisadas, visto que apenas 21,1% das amostras de LH e 11,3% das amostras de LNH apresentaram positividade para pelo menos 1 dos CTAs incluídos no painel de imunohistoquímica. MAGE-A (18,4%) e CT7 (13,2%) foram os CTAs mais frequentemente expressos em LH, enquanto MAGE-A (6,6%), GAGE (5,7%) e NY-ESO-1 (4,8%) foram os mais expressos em LNH. Apesar de não ter sido encontrada diferença estatisticamente significante na expressão de CTAs entre os subgrupos clínicos de LH, houve maior frequência de positividade nos pacientes com estadiamento avançado (28,6%), comparado àqueles com estadiamento inicial (11,8%). Nos subgrupos clínicos de LNH, a frequência de expressão de CTAs foi maior nos linfomas agressivos (14,9%) em relação aos indolentes (3,1%), nos linfomas difusos de grandes células B (LDGCB) (16,1%) comparado aos não-LDGCB (6,0%) e no subgrupo que não atingiu resposta completa (15,0%) comparado àqueles que obtiveram resposta completa (6,8%). Entretanto, as diferenças não foram estatisticamente significantes em nenhum desses subgrupos. Um achado inesperado no presente estudo foi a expressão mais frequente de CTAs no subgrupo de LNH com estadiamento inicial (I e II) comparado ao subgrupo com estadiamento avançado (III e IV). Apesar da diferença encontrada na análise de sobrevida entre o grupo de pacientes que não apresentaram expressão de CTA (sobrevida mediana de 65 meses) e aqueles que apresentaram expressão de pelo menos 1 CTA (sobrevida mediana de 11 meses), a diferença não foi estatisticamente significante (p=0.0947). A resposta humoral espontânea contra pelo menos 1 CTA do painel foi encontrada em 19,6% dos pacientes com LNH. CT47 foi o CTA mais frequentemente expresso (7.2%), seguido do CT45 (5.1%), NY-ESO-1 (5.1%) e MAGE-A4 (5.1%). Os CTAs foram mais frequentemente expressos em LNH de células B (21.2%) comparado aos LNH de células T (6.2%) (p=0.048). Não houve diferença estatisticamente significante na resposta humoral anti-CTAs em qualquer dos outros subgrupos clínicos de LNH. Conclusão: De forma geral, houve baixa expressão protéica de CTAs em nossa casuística de LH e LNH com o painel utilizado. Apesar dos limitados dados disponíveis na literatura, esses achados são concordantes com a maioria dos estudos realizados utilizando RT-PCR e/ou imunohistoquímica. Não houve correlações estatisticamente significantes entre expressão de CTAs e parâmetros clínicos ou prognósticos no presente estudo. A reatividade sérica contra os CTAs testados ocorreu em níveis semelhantes ao da expressão protéica em LNH, sugerindo que os pacientes com LNH são capazes de montar resposta imune humoral específica contra CTAs. / Cancer/testis antigens (CTAs) are expressed in a variety of malignant tumors but in normal adult tissues solely in testicular germ cells. Based on this tumor-associated expression pattern, these antigens are potential targets for immunotherapy. Though carcinomas have been extensively analyzed, less is known about lymphoid malignancies such as lymphomas. Aims: To evaluate the potential of tumor specific antigens as candidates for immunotherapy in lymphomas throughout CTA protein expression and spontaneous humoral immune response analyses. We also aim to investigate clinical correlations and prognostic impact of CTAs expression in lymphomas. Methods: Tissue microarray was generated from 38 Hodgkin´s lymphoma (HL) and 106 non- Hodgkin´s lymphoma (NHL) archival cases. Immunohistochemistry (IHC) was done using a panel of 9 monoclonal antibodies against CTAs. Spontaneous humoral immune response analysis against a larger CTA panel was performed in 97 untreated NHL patient samples, including 59 cases from the TMA cohort, using ELISA technique. Results: We found overall low expression of CTAs in our series of HL (21.1%) and NHL (11.3%) TMAs, being MAGE-A (18.4%) and CT7 (13.2%) the most frequently expressed CTAs in HL, and MAGE-A (6.6%), GAGE (5.7%), NY-ESO-1 (4.8%) and CT7 (4.8%) the most frequently expressed CTAs in NHL. Although we did not find statistically significant difference in CTA expression among the clinicopathological subgroups of HL, CTA positivity was higher in advanced stage (28.6%) compared to early stage patients (11.8%). Among NHL, we found higher CTA expression in aggressive lymphomas (14.9%) compared to indolent lymphomas (3.1%), DLBCL (16.1%) compared to non-DLBCL (6.0%) and in non-complete response group (15.0%) compared to those who achieved complete response (6.8%), but it was not statistically significant. Unexpectedly, early stage disease (19.5%) had higher CTA expression than advanced stage NHL (6.2%). Despite the difference found in survival analysis between NHL patients that presented no CTAs expression (median OS 65 months) and those who expressed at least one CTA (median OS 11 months), it did not reach statistically significant difference (p=0.0947). Serum reactivity against at least 1 CTA was observed in (19.6%) of NHL patients, being more frequent in B-cell lymphomas (21.2%) then T-cell lymphomas (6.2%) (p=0.048). CT47 was the most frequently expressed CTA (7.2%), followed by CT45 (5.1%), NY-ESO-1 (5.1%) and MAGE-A4 (5.1%). Grouping the MAGE-A family similarly to the TMA analysis, we found positivity in 8.2% of NHL serum samples. Among DLBCL, CT45 and NY-ESO-1 were the most frequently expressed CTAs, being positive in 4/50 (8.0%) and 3/50 (6.0%), respectively. Conclusion: We found overall low expression of CTAs in our series of HL and NHL TMAs, and low reactivity against CTA in our serum samples. Our results demonstrated a slightly higher frequency of humoral response against most CTAs included in both TMA and ELISA panel compared to their expression by TMA. Considering that generally a small proportion of patients expressing CTAs develop specific humoral response, it is possible that CTA expression by TMA could be underestimated due to the focal expression pattern in some patients. Therefore, using an extensive panel of antibodies and large TMA and serum cohorts of lymphoma patients, we could not identify CTA candidates for immunotherapy in HL and NHL. / TEDE / BV UNIFESP: Teses e dissertações
8

Caracterização da resposta imune humoral em trabalhadores da área da saúde frente a antígenos recombinantes de Mycobacterium tuberculosis / Characterization of humoral immune response of health care workers against recombinant antigens from Mycobacterium tuberculosis

REIS, Michelle Cristina Guerreiro dos 12 December 2007 (has links)
Made available in DSpace on 2014-07-29T15:30:39Z (GMT). No. of bitstreams: 1 Dissertacao Michelle Cristina Guerreiro dos Reis.pdf: 617682 bytes, checksum: a9f91c7541dba56bdf16a1188367288a (MD5) Previous issue date: 2007-12-12 / Tuberculosis (TB), one of the oldest disease in the world, is until our days a public health concern. It s believed that one third of the world s population is latently infected. Brazil is an endemic area for TB and its incidence in 2005 was about 60 cases per 100.000 inhabitants. One of the most important challenge in TB control is the identification of individuals who are latent infected. Health Care Workers (HCW) are at high risk of getting infected with Mycobacterium tuberculosis and because of that they had increased chances to became ill. The aim of this work was to elucidate the sorological profile of latent infected HCW through the antibody response against proteic recombinant antigens from Mycobacterium tuberculosis, GLcB, Hspx and MPT51. It was observed that almost 70% of HCW presented antibodies (IgM and IgG) against these antigens. When IgM was measured, the negative TST HCW showed higher antibodies s levels than the positive TST HCW. When IgG was measured, negative and positive TST HCW showed similar antibodies´s levels. Men and women also showed similar antibodies´s levels against those antigens. The antibodies s levels were also similar between BCG-vaccinated and BCG non-vaccinated HCW, the same occurs among the different professional categories. There isn t any relation between the antibody responses (humoral response) and TST results (cellular response). These results showed that the majority of the HCW presented antibodies against the proteic recombinant antigens GLcB, Hspx e MPT51 of Mycobacterium tuberculosis independent of the TST response. / A tuberculose (TB) é uma das doenças mais antigas do mundo e permanece até os dias atuais como um problema de saúde pública. Estima-se que um terço da população mundial está infectada. O Brasil é considerado área endêmica da TB e em 2005 apresentou taxe de incidência de 60 casos a cada 100.000 habitantes. Atualmente um dos principais desafios no controle da tuberculose é a identificação dos portadores latentes. Trabalhadores da área da saúde são expostos a um alto risco de infecção e por isso têm aumentadas as chances de se tornarem portadores latentes. Com intuito de elucidar o perfil sorológico de portadores latentes, avaliamos a resposta imune humoral de trabalhadores da área da saúde frente a antígenos recombinantes do Mycobacterium tuberculosis, GLcB, Hspx e MPT51, utilizando a técnica do ensaio imunoenzimático (ELISA). Constatou-se que quase 70% dos trabalhadores da saúde apresentaram anticorpos contra tais antígenos. Nas dosagens de IgM apenas naquela contra o Hspx os trabalhadores da saúde prova tuberculínica (PT) negativa apresentaram níveis de anticorpos superiores aos dos trabalhadores PT positiva. Nas dosagens de IgG trabalhadores PT negativa ou positiva apresentaram níveis semelhantes de anticorpos. Homens e mulheres apresentaram níveis similares de anticorpos (IgM ou IgG) contra os antígenos recombinantes. Os níveis de anticorpos de indivíduos BCGvacinados e BCG-não-vacinados também foram semelhantes, bem como entre indivíduos de diferentes categorias profissionais, independentemente da classe da imunoglobulina testada. Não houve correlação entre nível de anticorpo (resposta humoral) e o resultado da prova tuberculínica dos trabalhadores da saúde (resposta celular). Os resultados deste trabalho permitem concluir que os trabalhadores da área da saúde reconhecem os antígenos protéicos recombinantes GLcB, Hspx e MPT51 do Mycobacterium tuberculosis independentemente de reação à prova tuberculínica.
9

Resposta humoral de bovinos para os toxóides botulínicos C e D /

Curci, Vera Cláudia Lorenzetti Magalhães. January 2008 (has links)
Orientador: Iveraldo dos Santos Dutra / Banca: Júlio Cesar de Freitas / Banca: Tereza Cristina Cardoso da Silva / Banca: Raul José Silva Girio / Banca: Samir Issa Samara / Resumo: Foi avaliado pelo teste de ELISA indireto a resposta humoral para as toxinas botulínicas tipos C e D em animais vacinados com quatro diferentes produtos comerciais. Empregou-se duas vacinas bivalentes C e D (vacina 1 e vacina 2) e duas polivalentes contendo ainda os toxóides botulínicos tipos C e D (vacina 3 e vacina 4). Para análise foram realizadas seis colheitas de sangue ao longo do experimento, nos dias 0, 42, 75, 160, 250 e 342 após a vacinação. A imunidade passiva em bezerros até os 90 dias de idade, filhos de mães vacinadas com diferentes toxóides comerciais foram avaliados em 75 bezerros, agrupados de acordo com a vacina utilizada na mãe (B1, B2, B3 e B4). Para análise foram realizadas 3 colheitas de sangue, nos dias 5 (± 2), 45 e 90 dias após o nascimento. A avaliação da resposta humoral de bovinos vacinados em diferentes faixas etárias também foi realizada empregando-se uma vacina antibotulínica bivalente (C e D) comercial. Para análise, 90 bovinos foram divididos em 3 grupos de acordo com a faixa etária; animais com idade inferior a 2 anos, entre 2 e 5 anos e superior a 5 anos. Na avaliação da resposta humoral de animais vacinados com quatro diferentes produtos comerciais, para a toxina tipo C, as vacinas 1, 2, 3 e 4 não apresentaram diferenças significativas aos 42 dias da primeira dose. Aos 75 dias, a vacina 1, foi superior às vacinas 3 e 4, induzindo maior produção de anticorpos nos animais, porém não diferiu da vacina 2. Aos 160 dias houve queda na quantidade de anticorpos em todos os grupos, não havendo mais diferenças significativas entre as quatro vacinas testadas. Para a toxina tipo D, aos 42 dias da vacinação, não houve diferenças significativas entre as vacinas 1, 2 e 4, que apresentaram neste momento, valores superiores a vacina 3. No entanto, quando avaliadas aos 75 dias, a vacina 1 apresentou maior produção de anticorpos, diferindo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: To compare the efficiency of an "in house" ELISA test, standardized to measure antibody C and D from Clostridium botulinum, a survey to analysis four different commercial vaccines was conducted. The vaccines used were two commercial, bivalent botulinum containing subtypes C and D (vaccine 1 and vaccine 2) and other two polyvalent including subtypes C and D. The first trial was blood samples taken at 0, 42, 75, 160, 250 and 342 days after vaccination, whereas the booster was performed at day 42. The second trial, maternal antibodies were also measured taken blood samples from 1-3 months age steers obtained from vaccinated heifers with the same vaccines described above, and divided into four different groups (B1, B2, B3, B4). The blood samples were taken at days 5, 45 and 90 after birth. Third and last trial was humoral response from vaccinated cattle with different age evaluation performed using the commercial Clostridium botulinum vaccine subtype C and D. For this purpose, 90 animals never vaccinated, were divided into 3 groups: 1 - 2 years old; 2 - animals aged between 2 and 5 years old; 3 - animals 5 years old. The blood samples were taken 30 days after vaccination after second dose of the vaccine. From the first trial, no significant difference was observed when subtype C was search in sera from animals at 42 days after vaccination. However, at 75 days after vaccination, vaccine 1 was able to induce higher levels of antibodies when compared to vaccine 3 and 4. The antibody level was declining after 160 days post vaccination. For subtype D antigen, at 42 days after vaccination, no differences could be observed. However, at 75 day after vaccination, higher levels of antibodies were observed from animals vaccinated with vaccine 1. Comparing the bivalent vaccines, these were able to induce higher antibodies levels at 75 days after vaccination (toxoid C). In addition, the same... (Complete abstract click electronic access below) / Doutor
10

Etude des propriétés génétiques et fonctionnelles des variants du virus de l'hépatite C lors d'évènements de transmission / Study genetic and functionnal properties of Hepatitis C virus variants during transmission events

Guinoiseau, Thibault 29 January 2018 (has links)
Chez un individu infecté, le VHC circule sous la forme d’une population de variants viraux appelés quasi-espèce. Lors d’un évènement de transmission, certains variants viraux sont préférentiellement transmis et un effondrement de la diversité virale chez l’individu nouvellement infecté est souvent observé. Les propriétés électives de ces variants ainsi que leur rôle dans l’évolution clinique sont méconnus. L’objectif de cette étude est d’identifier si des déterminants moléculaires situés au niveau des glycoprotéines d’enveloppe du VHC sont associés à une plus grande capacité de transmission. Les propriétés fonctionnelles des variants transmis et non transmis seront étudiées, en particulier la sensibilité à la neutralisation autologue. Les échantillons étudiés proviennent de couples mère-enfant infectés chroniquement par le VHC issus de d’un essai clinique réalisé en Thaïlande. La composition des populations virales au sein de 3 paires a été étudiée à l’aide d’une technique d’amplification après dilution limite (SGA) suivie d’un séquençage profond (Illumina). Le variant majoritaire chez la mère était retrouvé majoritaire chez l’enfant pour les paires 1 et 3. Pour 2 paires (2 et 3), une moindre diversité génétique a été observée chez l’enfant par rapport à la mère témoignant d’un goulot d’étranglement génétique lors de la transmission. Après clonage des gènes E1E2, des tests d’infectivité sur cellules hépatocytaires ainsi que des tests de neutralisation par le sérum maternel sont réalisés avec le modèle de rétrovirus pseudotypés (VHCpp). Pour la 1ère paire, le variant majoritaire chez la mère (variant transmis à l’enfant) est infectieux et résistant au sérum autologue. Pour la deuxième paire, le variant minoritaire (transmis) est légèrement résistant à la neutralisation autologue. Un variant majoritaire non transmis apparait sensible à la neutralisation autologue. Des études complémentaires en système de virus réplicatifs issus de la culture cellulaire (VHCcc) sont en cours. Au final, les résultats de cette étude contribuent à comprendre les étapes précoces de l’infection par le VHC, afin de mieux appréhender de futures approches immunoprophylactiques ou vaccinales. / In infected individuals, HCV circulates as a complex mixture of genetically different, but closely related viral variants named quasispecies. In a transmission event, some viral variants are preferentially transmitted. The genetic and functional properties of these variants are still unknown. The aim of our work was to identify molecular determinants of E1E2 associates with a greater capacity of transmission. We also intend to study the functional properties of transmitted and no transmitted variants, as for example sensibility to autologous neutralization. Studied sera samples were obtained from three women and their child infected by the HCV, who were participating in HIV prevention clinical trial for the prevention of perinatal transmission of HIV in Thailand. Quasispecies were studied with single genome amplification (SGA) followed by deep sequencing (Illumina). A decrease in intra-host diversity (genetic bottleneck) was observed in the viral population of child near birth (week 6) compared with that observed in the mother (just before delivery). For 2 pairs, the major variant observed in the mother was the same as the major one identified in the child. Retroviral pseudotypes (HCVpp), bearing each transmitted and non-transmitted envelope glycoproteins were produced. For each one, the level of infectivity on HuH7 cells was measured as well as the neutralizing activity of the autologous sera. For the first pair, the major variant (transmitted) appears resistant to autologous neutralization. For the second pair, the transmitted minor variant appears slightly resistant to autologous neutralization. A non-transmitted major variant is sensitive to autologous neutralization. Complementary studies with HCV derived from cell culture (HCVcc) are in progress We hope that the results of this study may be helpful to better understand early steps of HCV infection, which is of great interest for the development of immunoprophylaxis and vaccine strategies.

Page generated in 0.4546 seconds