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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.
201

Percepção neural da alergia alimentar: envolvimento de mecanismos dependentes de IgE e das fibras nervosas do tipo C / Neural correlates of food allergy: role of IgE-dependent mechanisms and sensory C-fibers

Basso, Alexandre Salgado 20 August 2004 (has links)
Embora alguns estudos tenham considerado a possibilidade da existência de uma relação direta entre alergia alimentar e alterações de comportamento, são escassas as evidências que sustentem esta hipótese. Relatamos neste trabalho que, após desafio oral com o antígeno, camundongos sensibilizados com ovalbumina (OVA) apresentaram maiores níveis de ansiedade, maiores níveis séricos de corticosterona e aumento da imunorreatividade para Fos no núcleo paraventricular do hipotálamo (PVN) e no núcleo central da amígdala (CeA), áreas cerebrais relacionadas com emotividade. Os neurônios ativados pela alergia alimentar no PVN e no CeA são capazes de produzir fator liberador de corticotrofina (CRF). Os dados também demonstraram que a alergia alimentar leva à ativação do núcleo do trato solitário (NTS). Além disso, observamos que animais imunizados com OVA desenvolveram aversão à ingestão de uma solução contendo clara de ovo. Um tratamento com anticorpo anti-IgE ou a indução de tolerância oral bloquearam tanto o desenvolvimento da aversão à dieta contendo o antígeno quanto a expressão de c-fos no sistema nervoso central (SNC). Para investigar o modo pelo qual se dá a comunicação entre o cérebro e o intestino de animais com alergia alimentar, tratamos camundongos neonatalmente com capsaicina visando a destruição de fibras sensoriais do tipo C. O tratamento com capsaicina, embora não tenha impedido o desenvolvimento da aversão, diminuiu a sua magnitude. Ademais, este tratamento bloqueou completamente a ativação do PVN e diminuiu a expressão de c-fos induzida pela alergia alimentar no núcleo do trato solitário (NTS). Contudo, o tratamento com capsaicina não modificou a imunorreatividade para Fos no CeA de animais imunizados desafiados por via oral com o antígeno. Estes resultados demonstram claramente que a alergia alimentar influencia a atividade do SNC e o comportamento animal. Além disso, os dados obtidos evidenciam a participação de mecanismos dependentes de IgE e das fibras do tipo C na comunicação entre cérebro e o intestino de animais com alergia alimentar. De modo geral, além de enfatizar a relevância da integração entre os sistemas imune e nervoso na elaboração de respostas adaptativas, este estudo fornece subsídios para uma melhor compreensão de possíveis desordens de natureza psicológica em pacientes alérgicos. / Although many authors have considered the possibility of a direct interaction between food allergy and behavioral changes, the evidence supporting this hypothesis is elusive. Here we show that after oral OVA challenge allergic mice present higher levels of anxiety, increased serum corticosterone, and increased Fos expression in the paraventricular nucleus of the hypothalamus (PVN) and in the central nucleus of the amygdala (CeA), which are both emotionality-related brain areas. Food allergy-activated neurons in the PVN and in the CeA are able to produce CRF. We found that food allergy also induced enhanced Fos immunoreactivity in the nucleus of tractus solitarii (NTS) of OVA-immunized animals. Besides that, OVA-immunized animals developed aversion to an antigen-containing solution. Treatment with anti-IgE antibody, or induction of oral tolerance abrogated both food aversion and the expression of c-fos in the central nervous system. In order to investigate the brain-gut communication in allergic animals, we have employed destruction of sensory C fibers by neonatal capsaicin treatment. Although this treatment did not block development of food aversion, it decreased the magnitude of such aversion. Moreover, we observed that while the degree of Fos staining in the NTS of allergic mice was only diminished by neonatal capsaicin, it was completely blocked in the PVN. However, capsaicin did not modify food alergy-induced c-fos expression in the CeA. Besides establishing a direct relationship between brain function and food allergy, our findings provide evidence showing that IgE-dependent mechanisms and the sensory C fibers play an important role in food allergy signaling to the mouse brain. Finally, this study creates a solid ground for understanding the etiology of psychological disorders in allergic patients.
202

Diagnóstico de alergia por componentes em pacientes adultos com dermatite atópica / Component resolved diagnosis in adult patients with atopic dermatitis

Boufleur, Karine di Latella 22 May 2018 (has links)
Dermatite atópica (DA) é uma dermatose inflamatória, de caráter crônico e recidivante, com alta prevalência mundial, caracterizada por eczema localizado ou generalizado, xerose cutânea e prurido intenso, mais comum em crianças, porém podendo acometer adultos, muitas vezes prejudicando de forma considerável a qualidade de vida dos pacientes e seus familiares. O diagnóstico de alergia inclui testes in vivo (testes cutâneos de hipersensibilidade imediata ou prick test) e testes in vitro com mensuração de anticorpos IgE no sangue. Está disponível método para detecção de alergia baseado no princípio de diagnóstico por componentes, o ImmunoCAP Immunosorbent Allergen CHIP (ImmunoCAP-ISAC) que marca a transição para o diagnóstico molecular de alergia. No presente estudo, tivemos por objetivos determinar o perfil de resposta IgE a alérgenos purificados, naturais ou recombinantes, em pacientes adultos com DA e comparar o valor do diagnóstico de alergia por componentes com métodos diagnósticos existentes. Foram selecionados 39 pacientes adultos com DA dentre aqueles Atendidos nos Ambulatórios de Alergia e Dermatologia do HCFMRP-USP. A idade dos pacientes variou de 14-66 anos (média ± DP 34,3 ± 2.1 anos), 64% mulheres. O tempo médio de doença foi de 16 anos. SCORAD médio foi de 36,6 (2-90). Média geométrica (MG) de IgE total foi 1,963 kU/L (24-63,000 kU/L). Alérgenos de ácaros foram dominantes, com sensibilização a Der p1 e a Der f1, Der p2 e Der f2 em 82% e 85% dos pacientes, com MG 27,6; 50; 39,2; 45,4 ISU-E respectivamente, seguidos de gato (38%), cachorro (36%) e pólen de gramíneas (36%). IgE para alérgenos de baratas, fungos, pólen de árvores, látex e veneno de insetos foi encontrada em menos de 20% dos pacientes em baixos níveis. Sensibilização para castanhas (33%) e camarão (31%) foram os alérgenos mais prevalentes entre os alimentos, enquanto a reatividade IgE para leite e ovo esteve presente em 10% ou menos dos pacientes, com baixos níveis de anticorpos IgE na maioria dos casos. Apenas 6 pacientes (15,4%) apresentaram IgE para o panalérgeno tropomiosina, e 3/39 (7,7%) foram negativos para todos os 112 componentes de alérgenos testados no ImmunoCAP-ISAC, com níveis de IgE total de 24, 38,7 e 156 kU/L. Concluímos que o perfil de sensibilização IgE entre os pacientes adultos com dermatite atópica difere daquele entre os pacientes com alergiarespiratória, apresentando menos sensibilização para baratas e para o panalérgeno tropomiosina, e difere ainda do perfil presente em crianças com DA, com predomínio de sensibilização IgE a castanhas e camarão, e baixa taxa de sensibilização a alérgenos de leite de vaca e ovo. / Atopic dermatitis (AD) is an inflammatory, chronic, relapsing dermatosis with a high global prevalence characterized by localized or generalized eczema, cutaneous xerosis and intense pruritus, more common in children, but it can affect adults, often causing considerable damage to the quality of life of patients and their families. The diagnosis of allergy includes in vivo tests (skin tests of immediate hypersensitivity or prick test) and in vitro tests with measurement of IgE antibodies in the blood. An allergy detection method based on the principle of component diagnosis is available, ImmunoCAP Immunosorbent Allergen CHIP (ImmunoCAP-ISAC), and marks the transition to the molecular diagnosis of allergy. In the present study, we aimed to determine the IgE response profile to purified, natural or recombinant allergens in adult patients with AD and to compare the value of component allergy diagnosis with existing diagnostic methods. Thirty-nine adult patients with AD were selected from among those attending the Outpatient Clinic of Allergy and Dermatology at HCFMRP-USP. The age of the patients ranged from 14-66 years (mean ± SD 34,3 ± 2.1 years), 64% women. The mean duration of illness was 16 years. SCORAD mean was 36,6 (2- 90). Geometric mean (GM) of total IgE was 1,963 kU / L (24-63,000 kU / L). Mite allergens were dominant, with sensitization to Der p1 and Der f1, Der p2 and Der f2 in 82% and 85% of the patients, with GM 27,6; 50; 39.2; 45.4 ISU-E respectively, followed by cat (38%), dog (36%) and grass pollen (36%). IgE for cockroach, fungus, tree pollen, latex and insect venom allergens was found in less than 20% of patients at low levels. Sensitization to nuts (33%) and shrimp (31%) were the most prevalent allergens among foods, while IgE reactivity to milk and egg was present in 10% or less of the patients, with low levels of IgE antibodies in most cases. Only 6 patients (15.4%) presented IgE for the pan-allergen tropomyosin, and 3/39 (7.7%) were negative for all 112 allergen components tested on ImmunoCAP-ISAC, with total IgE levels of 24; 38,7 and 156 kU / L. We concluded that the IgE sensitization profile among adult patients with atopic dermatitis differs from that among patients with respiratory allergy, presenting less sensitization to cockroaches and to the pan-allergen tropomyosin, andalso differs from the profile present in children with AD, with a predominance of IgE sensitization to nuts and shrimp, and low sensitization rate to cow\'s milk and egg allergens.
203

American perceptions of allergies

Unknown Date (has links)
Allergies have taken on cultural meanings other than those offered by biomedicine. Interviews with allergic and non-allergic Americans were used to investigate the explanatory models of the lay population. This thesis uses ethnographic data to examine explanatory models of allergic conditions, highlighting metaphorical uses of allergies in American culture. The explanatory models of the subjects were contrasted to the biomedical model and the stereotypes created by the media in the United States. Important topics addressed in the analysis of the interview material were: what are the explanatory models of allergies in America, how do allergies influence the selfimage of someone with that condition, and how Americans with and without allergies perceive the allergic individual. / by Micheline M. Hilpert. / Thesis (M.A.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
204

Sensibilização ao extrato de Blomia tropicalis, na ausência de alum, requer a molécula adaptadora MyD88. / Sensitization to Blomia tropicalis extract without alum requires Myd88 adaptor molecule.

Yokoyama, Nicole Hune 19 February 2014 (has links)
Exposição a alérgenos de poeira doméstica é fator de risco para o desenvolvimento de doenças alérgicas. Os objetivos foram estudar a resposta inflamatória pulmonar alérgica induzida pela sensibilização i.n. ou s.c. ao extrato do ácaro Blomia tropicalis (Bt) e avaliar a participação da molécula adaptadora Myd88. Animais C57BL/6 sensibilizados com solução de extrato de Bt adsorvido ao alum exibiram altos níveis de IgE e aumento do número de eosinófilos. Contudo, animais sensibilizados apenas com Bt não apresentaram aumento dos níveis de IgE. Assim, animais C57BL/6 ou MyD88KO foram sensibilizados com uma dose maior do extrato de Bt (i.n. ou s.c.) e desafiados i.n. As sensibilizações produziram aumento do número células no BAL e níveis de IgE. Os parâmetros celulares em animais MyD88KO se mostraram inibidos, contudo, os níveis de IgE foram similares aos dos animais WT. Concluindo, o desenvolvimento de inflamação pulmonar alérgica não requer alum e sensibilização i.n. ou s.c. induz o recrutamento de células, dependente de MyD88 e produção de IgE, independe de MyD88. / Exposure to allergens from house dust is a risk factor for the development of allergic diseases. The objectives were to study the allergic lung inflammatory response induced by sensitization i.n. or s.c. to Blomia tropicalis (Bt) extract and determine the role of MyD88 adapter molecule. C57BL/6 mice sensitized with Bt extract solution adsorbed to alum exhibited high levels of IgE and increased numbers of eosinophils. However, animals sensitized only with Bt did not show increased levels of IgE. Thus, C57BL/6 or MyD88KO mice were sensitized with a higher dose of Bt extract (i.n. or s.c.) and challenged i.n. The sensitization produced increased cell number in BAL and IgE serum levels. Cell parameters were inhibited in MyD88KO mice, however, IgE levels were similar to those of WT mice. In conclusion, the development of allergic lung inflammation does not require alum, i.n. or s.c. sensitization induces cell recruitment dependent of MyD88 adaptor molecule and IgE production is independent of MyD88.
205

Spatial and Temporal Distribution of Tree Pollen in New York City: Linking Aeroallergen Measurements to Health

Weinberger, Kate Rebecca January 2015 (has links)
Allergic diseases affect a substantial proportion of people living in urban areas in the United States in general and in New York City (NYC) specifically. Many types of pollen are considered to be allergens, and have been linked to several manifestations of allergic disease, including allergic sensitization, exacerbation of allergic rhinitis, and exacerbation of allergic asthma. However, the role of pollen in determining temporal patterns of allergic disease is incompletely understood, and virtually nothing is known about the spatial distribution of pollen within cities and the relevance of this distribution to health. A better understanding of these relationships is especially critical as massive urban tree planting projects progress, and as the length and severity of the annual pollen season changes in response to changing temperature and carbon dioxide concentrations. The overall objective of this dissertation was to measure the spatial and temporal patterns of tree pollen in NYC and examine their associations with several allergic disease outcomes. Chapter 1 evaluates the health effects of the temporal distribution of pollen by examining the relationship between daily concentrations of several types of tree pollen measured in Armonk, NY with emergency department (ED) visits for asthma in NYC. We found that daily concentrations of four allergenic tree pollen genera were associated with a significantly increased rate of ED visits for asthma citywide. We further found that these associations were stronger in zip codes with higher tree canopy cover, suggesting that there may be spatial heterogeneity in tree pollen exposure within NYC not captured by the daily monitoring station. Chapter 2 tests the hypothesis that there is spatial variability in tree pollen within NYC by developing a novel dataset of spatial pollen measurements for the 2013 pollen season from 45 sites across NYC. These sites were co-located with an established network of air pollutant monitoring sites. Results from the 2013 monitoring campaign demonstrated substantial variability in tree pollen levels across the city. Total tree pollen deposition ranged from 2,942 grains per cm² to 17,460 grains per cm², a factor of almost six. Some individual tree pollen taxa exhibited an even greater degree of variation. We also developed a land use regression model for total tree pollen and tested the hypothesis that tree pollen influx at these sites is associated with tree canopy cover. When included alone in the model, percent tree canopy cover within a 0.5 km radial buffer of the monitoring sites explained 39% of the variance in tree pollen, while the inclusion of additional land use variables did not improve model fit. In Chapter 3, we use the land use regression model to develop tree pollen exposure estimates for children enrolled in the NYC Neighborhood Allergy and Asthma Study and evaluated whether modeled tree pollen influx for the first year of life is associated with allergic sensitization to tree pollen by age 7-8. We found that a standard deviation increase in tree pollen exposure in the first year of life was associated with a 50% increase in the prevalence of allergic sensitization to tree pollen. Furthermore, this association was stronger among children in the top 50% of black carbon exposure, suggesting that exposure to traffic-related pollutants may facilitate allergic sensitization.
206

Proteomic profiling of processing-induced modifications to food proteins

Sayers, Rebekah January 2017 (has links)
Peanut allergy typically results from sensitisation to one or more integral seed storage proteins; Ara h 1, 3 or 2/6. Reactions can be triggered by as little as 3 mg protein in 10% of allergic individuals and are often severe, inducing anaphylaxis which can be fatal. Accidental exposure through unintended presence can therefore be hazardous and foods must be labelled appropriately. Thermal processing is one of the main factors affecting protein properties in food systems, including the formation of Maillard reaction products. Research has suggested a link between the allergenicity of foods and cooking methods employed. A systematic study was undertaken to assess the thermal dependence of these hazard proteins, focusing on changes to solubility and chemical modifications which may alter IgE binding. Proteomic profiling was used to assess the allergenic content of peanut products and develop alternative methods for allergen analysis to support evidence-based application of precautionary allergen labelling. Runner variety peanuts were processed (boiled, fried, roasted) and their protein content determined. Proteins extracts were characterised by 1D- and 2D-polyacrylamide gel electrophoresis, including differential in-gel electrophoresis. Proteomic profiling was undertaken using label-free analysis to assess allergen composition and investigate the formation of Maillard reaction products on the most clinically relevant proteins. Peanut allergen peptide targets were then identified and used to develop label-based quantitation methods and applied to (i) investigate effects of processing on peptide targets and (ii) determine peanut in chocolate products in comparison with a commercial ELISA kit. Orthogonal studies were performed using serum samples from peanut allergic patients obtained from the Manchester Respiratory, Allergy and Thoracic Surgery (ManARTS) Biobank. Patient IgE reactivity to peanut and processed peanut products was assessed by immunoblotting, inhibition ELISA and mediator release assays. Protein solubility was reduced by thermal processing and processed protein required harsh denaturing conditions for extraction. Qualitative analysis highlighted decreased solubility of key allergens, modifications and aggregation after heating. Proteomic profiling identified and quantified different isoforms of the major peanut allergens. The protein content of processed peanuts was reduced by boiling, specifically the 2S albumins, which transferred into the cooking water. The performance of peptides selected for targeted MRM experiments was influenced by thermal processing and the presence of cocoa phenolics. Ara h 2 peptides flanked by arginine were thermostable and may prove more reliable for quantification. Application of microfluidic separation enhanced the efficiency of target ionisation in complex matrices acquiring important sensitivity gains. Maillard modifications to clinically relevant proteins Ara h 2/6 were found within IgE binding domains in raw and processed peanuts. IgE reactivity studies confirmed reduced IgE binding capacity of extensively boiled peanut and hydrolysed protein, but this did not correlate to a reduction in mediator release in poly-sensitised patients. While effective extraction limits the efficacy of analyses, buffers used in MS analyses are more robust in analysing processed protein. Proteomic profiling provides a means of characterising and profiling of allergenic proteins including food ingredients used in clinical applications. Peptides selected for targeted analyses should be validated to assess their suitability in model foods. Cooking waters collected from extensively boiled peanuts may provide an alternative and safer immunotherapy agent for patients predominantly sensitised to Ara h 2/6.
207

Mechanistic study of pruritogenic cytokine IL-31, alarmin IL-33 and ligands of NOD-like receptors on eosinophil-mediated inflammation in atopic dermatitis and allergic asthma.

January 2012 (has links)
過敏性疾病的患病率一直上升,約30%至40%的世界人口受到一個或多個過敏疾病影響。然而,現時仍然缺乏有效治療過敏性疾病的方法,大多數傳統療法只能改善臨床症狀,卻沒有針對導致過敏性炎症的主要因素。嗜酸性粒細胞浸入和積累於局部炎症部位以及延緩了的細胞凋亡是過敏性炎症的標誌,而嗜酸性粒細胞亦被認為是過敏性炎症的主要效應細胞。因此,針對嗜酸性粒細胞,抑制其活性和衍生產物,是一個有潛力和有效地治療過敏性炎症的策略。發展針對嗜酸性粒細胞的療法需要詳細了解嗜酸性粒細胞介導炎症反應的機制。 / 在第三章中,我們把嗜酸性粒細胞與皮膚成纖維細胞一起培養,建立了一個體外的皮膚炎症模型,用以研究嗜酸性粒細胞在過敏性皮炎發病病理中的作用。我們發現,嗜酸性粒細胞和成纖維細胞的共培養顯著誘導促炎性的細胞因子IL-6和濕疹相關趨化因子CXCL1,CXCL10,CCL2和CCL5的釋放。這些炎症介質的釋放在能導致皮膚瘙癢的細胞因子IL-31和內源性警報因子IL-33的刺激下進一步加強。 IL-31和IL-33可顯著引起嗜酸性粒細胞和成纖維細胞釋放CXCL8,而當兩種細胞共培養後,CXCL8的釋放進一步增強。在共培養系統中,嗜酸性粒細胞是釋放CCL5的主要來源,而成纖維細胞則是釋放IL-6,CXCL1, CXCL8,CXCL10和CCL2的主要來源。嗜酸性粒細胞和成纖維細胞之間的直接相互作用是CXCL1,CXCL10,CXCL8和CCL5的釋放所必需的。在IL-31和IL-33的刺激下,共培養系統中嗜酸性粒細胞和成纖維細胞的細胞表面粘附分子ICAM-1的表達上調。而嗜酸性粒細胞和成纖維細胞間的互作用,以及IL-31和IL-33對兩種細胞的激活,是經由p38、ERK、JNK,NF-κB和PI3K-AK訊息傳遞徑路所調節的。另外,我們亦發現1,25-二羥維生素D3能顯著抑製共培養系統在IL-31或IL-33激活下IL-6,CCL2和CXCL8的釋放。 / 在第四章中,我們探討在嗜酸性粒細胞和支氣管上皮細胞BEAS-2B的共培養系統中,兩種細胞的細菌相關模式識別受體成員NOD1和NOD2激活機制。我們發現NOD配體iE-DAP和NOD2配體MDP能激活嗜酸性粒細胞內的ERK和NF-κB信號傳導通路,而MDP可以激活嗜酸性粒細胞和BEAS-2B細胞的ERK信號傳導通路。當嗜酸性粒細胞和BEAS-2B細胞共培養時,iE-DAP和MDP均可激活嗜酸性粒細胞和BEAS-2B細胞的ERK和NF-κB信號傳導通路,而且與單獨培養的細胞相比,激活的程度更強。此外,我們還探討了iE-DAP和MDP對 BEAS-2B細胞和嗜酸性粒細胞的核轉錄因子的激活作用。我們發現iE-DAP和MDP可以激活嗜酸性粒細胞和BEAS-2B細胞的某些轉錄因子,包括因子NF-κB、STAT-3和NFAT等,而多數被激活的轉錄因子都跟過敏性炎症和哮喘的發病有關。除了體外研究,我們還建立了過敏性肺部炎症的小鼠模型,用以研究iE-DAP和MDP的生理效應。iE-DAP和MDP均可激活第二型輔助性T細胞相關的免疫球蛋白E生產,以及誘導嗜酸性粒細胞趨化因子CCL5。 / 上述的研究結果表明IL-31與IL-33在過敏性皮炎的發病病理中發揮關鍵作用,通過不同的信號傳導機制激活嗜酸性粒細胞與成纖維細胞的相互作用。另外,我們探討了在嗜酸性粒細胞和BEAS-2B細胞中,調節NOD1和NOD2激活的信號傳導機制,加上動物實驗,所得的結果有助了解細菌感染在哮喘發作中所發揮的影響。這些關於細胞之間和細胞內調控機制的研究結果,進一步增強我們對嗜酸性粒細胞介導炎症的理解,並為發展更高專一性、效用和更少副作用的消炎藥提供了新的標靶和方向。 / The prevalence of allergic diseases has been steadily increased, with about 30-40% of the world population being affected by one or more allergic conditions. Effective treatments on allergic diseases are still lacking, as most of the traditional therapies aim at clinical improvement without targeting the factors that primarily promote the allergic inflammation. Infiltration, delayed apoptosis and accumulation of eosinophils at the local inflammatory sites are the hallmarks of allergic inflammation and eosinophils are considered as the principal effector cells in allergic inflammation. Anti-eosinophils therapeutics inhibit eosinophil activity and eosinophil-derived products are thus potential strategies in treating allergic inflammation effectively. Elucidation of the detailed mechanisms of eosinophil-mediated inflammation is therefore necessary for the development of anti-eosinophils therapeutics. / In Chapter 3, we established an in vitro skin inflammation model by co-culturing eosinophils with dermal fibroblasts in order to study the pathophysiology of eosinophils’ involvement in the pathogenesis of atopic dermatitis (AD). We revealed that co-culture of eosinophils and fibroblasts significantly induced release of pro-inflammatory cytokine IL-6 and AD-related chemokines CXCL1, CXCL10, CCL2 and CCL5. Such inductions were further enhanced with pruritogenic cytokine IL-31 and endogenous alarmin IL-33 stimulation. IL-31 and IL-33 could significantly provoke the release of CXCL8 from eosinophils and fibroblasts, respectively, which was further enhanced upon co-culture. In co-culture, eosinophils and fibroblasts were the main source for the release of CCL5, and IL-6, CXCL1, CXCL8, CXCL10 and CCL2, respectively. Direct interaction between eosinophils and fibroblasts was required for CXCL1, CXCL10, CXCL8 and CCL5 release. Cell surface expression of intercellular adhesion molecule-1 on eosinophils and fibroblasts was upregulated in co-culture upon IL-31 and IL-33 stimulation. The interaction between eosinophils and fibroblasts under IL-31 and IL-33 stimulation differentially activated ERK, JNK, p38 MAPK, NF-κB and PI3KAkt pathways. 1,25-dihydroxy vitamin D3 exerted in vitro suppressive effect on the release of IL-6, CCL2 and CXCL8 release from IL-31 or IL-33 activated co-culture of eosinophils and fibroblasts. / In Chapter 4, we revealed the mechanisms underlying bacterial-related pattern recognition receptor members NOD1 and NOD2 activation in eosinophils and bronchial epithelial cells BEAS-2B from the co-culture system and animal model experiment. NOD1 ligand iE-DAP and NOD2 ligand MDP could activate ERK and NF-κB pathways in eosinophils, while MDP stimulation could activate ERK in both eosinophils and BEAS-2B cells. When the eosinophils and BEAS-2B cells were co-cultured together, both iE-DAP and MDP could induce ERK and NF-κB activation in the two cells, and the activation was enhanced when compared with that in cells cultured alone. Besides, we also investigated the transcription factors activation in eosinophils and BEAS-2B cells by iE-DAP and MDP. iE-DAP and MDP could also activate a panel of transcription factors in eosinophils and BEAS-2B cells, including NF-κB, STAT-3 and NFAT etc, the nuclear transcription factors commonly involved in allergic inflammation and related to the pathogenesis of asthma. Apart from in vitro study, we also established an in vivo allergic pulmonary inflammation mice model to study the physiological effects of iE-DAP and MDP. Both iE-DAP and MDP could activate the Th2 related IgE production and induce eosinophil chemokine CCL5. / The above findings suggest a crucial immunopathological role of IL-31 and IL-33 in AD through the activation of eosinophils-fibroblasts interaction via differential intracellular signaling mechanisms. The intracellular signaling mechanisms regulating NOD1 and NOD2 activation in eosinophils and bronchial epithelial cells and animal experiment were also revealed and give implications of the role of bacterial infections in the exacerbation of asthma. Such information further enhances our understandings on both the intercellular and intracellular mechanisms of eosinophil-mediated inflammation, and gives implications for new targets for the development of anti-inflammatory drugs with higher specificity, potency, and less side effects. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Leung, Ming Lam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 136-153). / Abstracts also in Chinese. / ACKNOWLEDGEMENTS --- p.I / ABSTRACT --- p.III / 摘要 --- p.VI / PUBLICATIONS --- p.IX / ABBREVIATIONS --- p.XI / TABLE OF CONTENTS --- p.XIV / Chapter Chapter 1 --- : General Introduction / Chapter 1.1 --- Allergy --- p.1 / Chapter 1.1.1 --- Definition and characteristics of allergy --- p.1 / Chapter 1.1.2 --- Allergic diseases and their prevalence --- p.2 / Chapter 1.1.3 --- Allergic inflammation --- p.2 / Chapter 1.2 --- Biology of eosinophils --- p.8 / Chapter 1.2.1 --- Development of eosinophils --- p.8 / Chapter 1.2.2 --- Cellular characteristics of eosinophils --- p.9 / Chapter 1.2.3 --- Eosinophils surface and intracellular markers --- p.10 / Chapter 1.2.4 --- Eosinophil-derived mediators --- p.13 / Chapter 1.2.5 --- Accumulation and activation of eosinophils at inflammatory sites --- p.16 / Chapter 1.3 --- Adhesion molecules in allergic inflammation --- p.19 / Chapter 1.3.1 --- Selectins --- p.19 / Chapter 1.3.2 --- Integrins --- p.20 / Chapter 1.3.3 --- Immunoglobulin gene super family --- p.21 / Chapter 1.4 --- Cytokines in allergic inflammation --- p.23 / Chapter 1.4.1 --- Pro-inflammatory cytokines --- p.23 / Chapter 1.4.2 --- Anti-inflammatory cytokines --- p.25 / Chapter 1.5 --- Chemokines in allergic inflammation --- p.27 / Chapter 1.6 --- Signal transduction in allergic inflammation --- p.29 / Chapter 1.6.1 --- Intracellular signaling mechanisms --- p.29 / Chapter 1.6.2 --- Transcription factors activation --- p.33 / Chapter 1.7 --- Perspective treatments --- p.36 / Chapter 1.7.1 --- Inhibition of pro-inflammatory cytokines --- p.36 / Chapter 1.7.2 --- Inhibition of chemokines --- p.37 / Chapter 1.7.3 --- Small interfering (si)RNA against transcription factor --- p.37 / Chapter 1.7.4 --- Signaling pathway inhibitors --- p.38 / Chapter 1.8 --- Aim of study --- p.39 / Chapter Chapter 2 --- : Materials and Methods / Chapter 2.1 --- Materials --- p.42 / Chapter 2.2 --- Methods --- p.60 / Chapter 2.2.1 --- Purification of human eosinophils --- p.60 / Chapter 2.2.2 --- Cell culture --- p.61 / Chapter 2.2.3 --- Cell surface and intracellular immunofluorescence staining --- p.63 / Chapter 2.2.4 --- Western blot --- p.64 / Chapter 2.2.5 --- Allergic asthmatic mice model --- p.64 / Chapter 2.2.6 --- Statistical analysis --- p.65 / Chapter Chapter 3 --- : Activation of Eosinophils Interacting with Dermal Fibroblasts by Pruritogenic Cytokine IL-31 and Alarmin IL-33: Implications in Atopic Dermatitis / Chapter 3.1 --- Introduction --- p.66 / Chapter 3.1.1 --- Atopic dermatitis --- p.66 / Chapter 3.1.2 --- Eosinophils in AD --- p.68 / Chapter 3.1.3 --- IL-31 --- p.68 / Chapter 3.1.4 --- IL-33 --- p.70 / Chapter 3.1.5 --- Vitamin D --- p.71 / Chapter 3.1.6 --- Hypothesis and aim of study --- p.73 / Chapter 3.2 --- Results --- p.74 / Chapter 3.2.1 --- Surface expression of receptors for IL-31 and IL-33 on human eosinophils and dermal fibroblasts --- p.74 / Chapter 3.2.2 --- Cytokine and chemokine release upon the interaction of eosinophils and dermal fibroblasts activated by IL-31 and IL-33 --- p.77 / Chapter 3.2.3 --- Source of the release of cytokines and chemokines in the co-culture system upon IL-31 and IL-33 stimulation --- p.80 / Chapter 3.2.4 --- Effect of transwell inserts on cytokine and chemokine release in IL-31 and IL-33-treated co-culture --- p.83 / Chapter 3.2.5 --- Effect of IL-31 and IL-33 on adhesion molecule expression on eosinophils and dermal fibroblast in co-culture system --- p.86 / Chapter 3.2.6 --- Intracellular signaling pathways involved in the interaction of eosinophils and dermal fibroblasts under IL-31 and IL-33 stimulation --- p.88 / Chapter 3.2.7 --- Surface expression of vitamin D receptor on human eosinophils and dermal fibroblasts --- p.96 / Chapter 3.2.8 --- Suppressive effects of 1,25-dihydroxy vitamin D₃ (calcitriol) on cytokine and chemokine release from IL-31 and IL-33-treated co-culture --- p.97 / Chapter 3.3 --- Discussion --- p.100 / Chapter Chapter 4 --- :Intracellular Signal Transduction Mechanisms of NLR Activation in Human Eosinophils and Bronchial Epithelial Cells: Implication for Bacterial Infection in Allergic Asthma / Chapter 4.1 --- Introduction --- p.107 / Chapter 4.1.1 --- Allergic asthma --- p.107 / Chapter 4.1.2 --- Eosinophils in allergic asthma --- p.108 / Chapter 4.1.3 --- NOD-like receptors --- p.109 / Chapter 4.1.4 --- Hypothesis and aim of study --- p.110 / Chapter 4.2 --- Results --- p.112 / Chapter 4.2.1 --- Intracellular signaling pathways involved in the interaction of eosinophils and BEAS-2B cells under iE-DAP and MDP stimulation --- p.112 / Chapter 4.2.2 --- Transcription factors activation in eosinophils and BEAS-2B cells under iE-DAP and MDP stimulation --- p.119 / Chapter 4.2.3 --- In vivo activating effect of NOD1,2 ligands on the IgE and chemokine concentration in serum and BALF in allergic asthmatic mice --- p.122 / Chapter 4.3 --- Discussion --- p.125 / Chapter Chapter 5 --- : Concluding Remarks and Future Studies / Chapter 5.1 --- Concluding remarks --- p.130 / Chapter 5.2 --- Future studies --- p.131 / REFERENCES --- p.136
208

Characterization of lysine-rich protein (LRP) in winged bean.

January 2003 (has links)
Wong Ho Wan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 140-153). / Abstracts in English and Chinese. / Thesis Committee --- p.I / Statement --- p.II / Acknowledgements --- p.III / Abstract --- p.IV / 摘要 --- p.VI / List of Tables --- p.VIII / List of Figures --- p.IX / List of Abbreviations --- p.XI / Table of Contents --- p.XIII / Chapter 1 --- General introduction --- p.1 / Chapter 2 --- Literature reviews --- p.4 / Chapter 2.1 --- LRP and winged bean --- p.4 / Chapter 2.1.1 --- Nutritional values of crop plants --- p.4 / Chapter 2.1.2 --- Lysine-rich protein (LRP) --- p.7 / Chapter 2.1.2.1 --- Identification of lysine-rich protein (LRP) --- p.7 / Chapter 2.1.2.2 --- Cloning cDNA for WBLRP --- p.7 / Chapter 2.1.2.3 --- Transgenic Expression of LRP in other plants --- p.8 / Chapter 2.1.3 --- Unknowns remained --- p.8 / Chapter 2.2 --- Food allergy and gastro-immunity --- p.10 / Chapter 2.2.1 --- What is allergy? 一 A brief introduction --- p.10 / Chapter 2.2.2 --- Food allergy and its symptoms --- p.12 / Chapter 2.2.3 --- Gastrointestinal immunity --- p.13 / Chapter 2.2.4 --- Possible mechanism of food allergy --- p.16 / Chapter 2.2.5 --- Available tests and limitations --- p.18 / Chapter 2.2.6 --- Radioallergosorbent test (RAST) --- p.19 / Chapter 2.2.7 --- Digestibility test --- p.20 / Chapter 2.2.8 --- Betv-1 Allergen Family --- p.21 / Proteins --- p.23 / Chapter 2.3 --- Pathogenesis-related proteins --- p.23 / Chapter 2.3.1 --- Defense-related proteins and pathogenesis-related proteins (PRs) --- p.23 / Chapter 2.3.2 --- Class 10 PR proteins (PR-10s) --- p.25 / Chapter 2.3.3 --- The expression patterns of PR-10s --- p.27 / Chapter 2.3.3.1 --- Pathogens-induced and signal-induced expression --- p.27 / Chapter 2.3.3.2 --- Spatially- and developmentally-regulated expression --- p.28 / Chapter 2.3.3.3 --- Other induction patterns --- p.29 / Chapter 2.3.4 --- Functions ofPR-10s --- p.30 / Chapter 2.4 --- Development of hypotheses and experiments --- p.32 / Chapter 3 --- Materials and methods --- p.36 / Chapter 3.1 --- Introduction --- p.36 / Chapter 3.2 --- Materials --- p.38 / Chapter 3.2.1 --- Chemicals --- p.38 / Chapter 3.2.2 --- Apparatus and commercial kits --- p.39 / Chapter 3.2.3 --- Vectors and bacterial strains --- p.39 / Chapter 3.2.4 --- Plant and animal materials --- p.40 / Chapter 3.2.5 --- Computer software --- p.40 / Chapter 3.3 --- Purification of LRP --- p.41 / Chapter 3.3.1 --- Purification of LRP from winged bean --- p.41 / Chapter 3.3.1.1 --- Extraction of total protein --- p.41 / Chapter 3.3.1.2 --- Differential pI precipitation --- p.41 / Chapter 3.3.1.3 --- Determination of the pI point of LRP --- p.42 / Chapter 3.3.1.4 --- Native tricine-PAGE and gel elution --- p.42 / Chapter 3.3.2 --- Purification from E. coli --- p.45 / Chapter 3.3.2.1 --- Construction of pET vector expressing recombinant LRP (rLRP) --- p.45 / Chapter 3.3.2.2 --- Expression of rLRP --- p.50 / Chapter 3.3.2.3 --- Purification by gel electrophoresis and gel band elution --- p.50 / Chapter 3.4 --- Anti-serum production --- p.52 / Chapter 3.5 --- Allergy tests --- p.53 / Chapter 3.5.1 --- Pepsin digestion --- p.53 / Chapter 3.5.1.1 --- Determination of optimal concentration of pepsin --- p.53 / Chapter 3.5.1.2 --- Pepsin digestion of allergenic and non-allergenic model proteins --- p.55 / Chapter 3.5.1.3 --- Pepsin digestion of LRP and immunodetection --- p.55 / Chapter 3.5.2 --- Trypsin digestion --- p.56 / Chapter 3.5.2.1 --- Determination of optimal trypsin concentration --- p.56 / Chapter 3.5.2.2 --- Trypsin digestion of allergenic and non-allergenic model proteins --- p.57 / Chapter 3.5.2.3 --- Trypsin digestion of LRP and immuno-detection --- p.57 / Chapter 3.5.3 --- Pepsin and trypsin digestion --- p.58 / Chapter 3.5.3.1 --- Digestions of allergenic model proteins --- p.58 / Chapter 3.5.3.2 --- Digestion of LRP --- p.58 / Chapter 3.5.4 --- IgE binding tests --- p.58 / Chapter 3.6 --- Physiology studies --- p.59 / Chapter 3.6.1 --- Preparation for the studies --- p.59 / Chapter 3.6.1.1 --- Growing winged bean in the field --- p.59 / Chapter 3.6.1.2 --- Growing winged bean in sterile conditions --- p.60 / Chapter 3.6.1.3 --- Production ofLRP-cDNA probe --- p.60 / Chapter 3.6.2 --- Detecting the expression of LRP in winged bean --- p.61 / Chapter 3.6.2.1 --- RNA extraction --- p.61 / Chapter 3.6.2.2 --- RT-PCR and DNA sequencing --- p.62 / Chapter 3.6.2.3 --- RNA electrophoresis and northern blot analysis --- p.63 / Chapter 3.6.2.4 --- Protein extraction --- p.63 / Chapter 3.6.2.5 --- Western blot and immuno-detection --- p.63 / Chapter 3.6.3 --- Expression of LRP in germinating winged bean seeds --- p.64 / Chapter 3.6.3.1 --- Seed germination --- p.64 / Chapter 3.6.3.2 --- Detection of LRP in germinating seeds --- p.64 / Chapter 3.6.4 --- RNase activity test --- p.65 / Chapter 4 --- Results --- p.67 / Chapter 4.1 --- Purification of LRP --- p.67 / Chapter 4.1.1 --- Purification from winged bean --- p.67 / Chapter 4.1.1.1 --- Identification of pI point of LRP --- p.67 / Chapter 4.1.1.2 --- Native tricine PAGE and gel elution --- p.70 / Chapter 4.1.2 --- Purification from E. coli --- p.71 / Chapter 4.1.2.1 --- Construction of pET-LRP vector --- p.71 / Chapter 4.1.2.2 --- Expression of rLRP and gel purification --- p.74 / Chapter 4.2 --- Antiserum production --- p.76 / Chapter 4.3 --- Allergy tests --- p.81 / Chapter 4.3.1 --- Pepsin digestion --- p.81 / Chapter 4.3.2 --- Trypsin digestion --- p.89 / Chapter 4.3.3 --- Pepsin and trypsin digestion --- p.96 / Chapter 4.3.4 --- Human serum IgE binding test --- p.104 / Chapter 4.4 --- Physiological studies --- p.105 / Chapter 4.4.1 --- Samples preparation --- p.105 / Chapter 4.4.2 --- RT-PCR and DNA sequencing --- p.105 / Chapter 4.4.3 --- Expression profile of WBLRP in winged bean somatic organs --- p.108 / Chapter 4.4.4 --- Expression profile ofWBLRP in winged bean flower --- p.111 / Chapter 4.4.5 --- Expression profile ofWBLRP in winged bean maturing seeds --- p.114 / Chapter 4.4.6 --- Expression profile of WBLRP gene in winged bean germinating seeds --- p.117 / Chapter 4.4.7 --- Functional assay of LRP --- p.121 / Chapter 5 --- Discussion --- p.124 / Chapter 5.1 --- LRP purification and antibody production --- p.124 / Chapter 5.2 --- Allergy tests --- p.125 / Chapter 5.3 --- Expression of LRP in WB --- p.131 / Chapter 5.4 --- Functional assay of LRP --- p.134 / Chapter 5.5 --- Hypothesis Testing --- p.135 / Chapter 5.6 --- Future prospective, --- p.136 / Chapter 6 --- Conclusion --- p.138 / Chapter 7 --- References --- p.140
209

Percepção neural da alergia alimentar: envolvimento de mecanismos dependentes de IgE e das fibras nervosas do tipo C / Neural correlates of food allergy: role of IgE-dependent mechanisms and sensory C-fibers

Alexandre Salgado Basso 20 August 2004 (has links)
Embora alguns estudos tenham considerado a possibilidade da existência de uma relação direta entre alergia alimentar e alterações de comportamento, são escassas as evidências que sustentem esta hipótese. Relatamos neste trabalho que, após desafio oral com o antígeno, camundongos sensibilizados com ovalbumina (OVA) apresentaram maiores níveis de ansiedade, maiores níveis séricos de corticosterona e aumento da imunorreatividade para Fos no núcleo paraventricular do hipotálamo (PVN) e no núcleo central da amígdala (CeA), áreas cerebrais relacionadas com emotividade. Os neurônios ativados pela alergia alimentar no PVN e no CeA são capazes de produzir fator liberador de corticotrofina (CRF). Os dados também demonstraram que a alergia alimentar leva à ativação do núcleo do trato solitário (NTS). Além disso, observamos que animais imunizados com OVA desenvolveram aversão à ingestão de uma solução contendo clara de ovo. Um tratamento com anticorpo anti-IgE ou a indução de tolerância oral bloquearam tanto o desenvolvimento da aversão à dieta contendo o antígeno quanto a expressão de c-fos no sistema nervoso central (SNC). Para investigar o modo pelo qual se dá a comunicação entre o cérebro e o intestino de animais com alergia alimentar, tratamos camundongos neonatalmente com capsaicina visando a destruição de fibras sensoriais do tipo C. O tratamento com capsaicina, embora não tenha impedido o desenvolvimento da aversão, diminuiu a sua magnitude. Ademais, este tratamento bloqueou completamente a ativação do PVN e diminuiu a expressão de c-fos induzida pela alergia alimentar no núcleo do trato solitário (NTS). Contudo, o tratamento com capsaicina não modificou a imunorreatividade para Fos no CeA de animais imunizados desafiados por via oral com o antígeno. Estes resultados demonstram claramente que a alergia alimentar influencia a atividade do SNC e o comportamento animal. Além disso, os dados obtidos evidenciam a participação de mecanismos dependentes de IgE e das fibras do tipo C na comunicação entre cérebro e o intestino de animais com alergia alimentar. De modo geral, além de enfatizar a relevância da integração entre os sistemas imune e nervoso na elaboração de respostas adaptativas, este estudo fornece subsídios para uma melhor compreensão de possíveis desordens de natureza psicológica em pacientes alérgicos. / Although many authors have considered the possibility of a direct interaction between food allergy and behavioral changes, the evidence supporting this hypothesis is elusive. Here we show that after oral OVA challenge allergic mice present higher levels of anxiety, increased serum corticosterone, and increased Fos expression in the paraventricular nucleus of the hypothalamus (PVN) and in the central nucleus of the amygdala (CeA), which are both emotionality-related brain areas. Food allergy-activated neurons in the PVN and in the CeA are able to produce CRF. We found that food allergy also induced enhanced Fos immunoreactivity in the nucleus of tractus solitarii (NTS) of OVA-immunized animals. Besides that, OVA-immunized animals developed aversion to an antigen-containing solution. Treatment with anti-IgE antibody, or induction of oral tolerance abrogated both food aversion and the expression of c-fos in the central nervous system. In order to investigate the brain-gut communication in allergic animals, we have employed destruction of sensory C fibers by neonatal capsaicin treatment. Although this treatment did not block development of food aversion, it decreased the magnitude of such aversion. Moreover, we observed that while the degree of Fos staining in the NTS of allergic mice was only diminished by neonatal capsaicin, it was completely blocked in the PVN. However, capsaicin did not modify food alergy-induced c-fos expression in the CeA. Besides establishing a direct relationship between brain function and food allergy, our findings provide evidence showing that IgE-dependent mechanisms and the sensory C fibers play an important role in food allergy signaling to the mouse brain. Finally, this study creates a solid ground for understanding the etiology of psychological disorders in allergic patients.
210

Biodegradable particles as vaccine delivery systems

Joshi, Vijaya Bharti 01 July 2014 (has links)
Immunotherapy has been widely investigated in cancer, infectious diseases and allergies for prevention or amelioration of disease progression. In the case of vaccines, the key cellular target in stimulating an effective and appropriate immune response is the professional antigen presenting cell or dendritic cell (DC). Cancer vaccines are primarily aimed at the activation of a tumor-specific cytotoxic T lymphocyte (CTL) response whilst vaccines to allergies are aimed at reducing IgE responses. Such vaccines normally involve the administration tumor-associated antigens (TAAs) for cancer, or antigens (Ags) derived from infectious microbes and allergens in the case of allergies. Ags, whether derived from tumor or allergen, can be combined with adjuvants, that include immunostimulatory molecules recognized by the pathogen associated receptors expressed by DCs and can trigger the activation/maturation of DCs. Co-delivery of an appropriate adjuvant with an Ag can stimulate DCs to subsequently promote a robust Ag-specific CTL response which may favor anti-tumor immunity. Cancer vaccines have been widely investigated in the clinics as a complementary therapy to surgery, radiation and chemotherapy. Activation of CTLs against tumor cells that express TAAs could lead to the complete eradication of a cancer and prevent its reoccurrence. In this study I developed microparticles using a polyanhydride polymer prepared from 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG) and 1,6-bis(p-carboxyphenoxy) hexane (CPH) that has shown inherent adjuvant properties. I prepared 50:50 CPTEG:CPH microparticles encapsulating a model tumor Ag, ovalbumin (OVA), and synthetic oligonucleotide containing an unmethylated CpG motif, CpG, as an adjuvant. CpG has shown significant potential as an adjuvant for TAA-based vaccines leading to significant anti-tumor immune activity. I have shown that mice vaccinated with OVA-encapsulated 50:50 CPTEG:CPH microparticles developed OVA-specific CTL responses. These mice showed enhanced survival compared to the control treatment groups when challenged with OVA expressing tumor cells . In a more novel in-situ cancer vaccine, TAAs from dying tumor cells (caused by certain chemotherapeutic drugs) can be used as the source of Ags delivered to DCs. The presence of an adjuvant with dying cancer cells can assist in appropriate maturation of DCs so as to promote the generation of an effective tumor/TAA-specific CTL response against released TAAs. In this work I developed a therapeutic in situ tumor vaccine encapsulating a chemotherapeutic drug and CpG. Doxorubicin (Dox) is a widely used chemotherapeutic drug that induces tumor cells to undergo an immunogenic form of apoptosis. Sustained release of Dox in solid tumors of mice can cause the release of a variety of TAAs which can be presented by DCs and, in the presence of CpG, stimulate a strong anti-tumor CTL response. I prepared formulations of poly(lactic-co-glycolic acid) (PLGA) particles loaded with Dox and CpG which demonstrated sustained release of their cargo. I show that among various formulations of Dox and CpG, co-delivery of Dox and CpG in the same PLGA particles in-vivo showed the highest reduction in tumor growth and longest survival when compared to treatment groups of PLGA particles delivering Dox and CpG either alone or in combination. PLGA particles have also been investigated as a prophylactic vaccine delivery system that generates a robust Ag-specific CTL response. This system has been employed for the development of vaccines against various infectious diseases and allergies. However, there has been conflicting opinions regarding the optimum size of PLGA particles required to stimulate an active CTL response. Thus, I developed different sizes of PLGA particles encapsulating OVA and CpG to study the relationship of particle size with the magnitude of OVA-specific CTL responses. I showed that the degree of particle uptake and activation of DCs increased with decreasing size of PLGA particles. I also showed that immunization of mice with 300 nm sized particles demonstrated a higher proportion of OVA-specific CTLs and increased the secretion of IgG2a antibody responses. I also evaluated the efficacy of these particles with a clinically relevant Ag, Dermatophagoides pteronyssinus-2 (Der p2). Mice vaccinated with different sizes of PLGA particles loaded with CpG and coated with Der p2 displayed different magnitudes and types of immune activation against Der p2. The small sized particles decreased the airway hyperresponsiveness associated with allergy-induced asthma. The presence of CpG in the PLGA particle vaccines also reduced the airway hyperresponsiveness. This thesis research has contributed to the identification and development of a delivery system for Dox in combination with CpG which gives sustained release of these molecules within tumors and show the longest survival in tumor bearing mice. This study also optimized the size of PLGA particles for the delivery of vaccine to produce a robust Ag specific immune response for development of vaccination against intracellular diseases, cancer and allergy.

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