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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.
141

Immune Responses to Gene Product of Inducible Promoters

Le Guiner, Caroline, Stieger, Knut, Synder, Richard O., Rolling, Fabienne, Moullier, Philippe 01 October 2007 (has links)
Efficient gene transfer has been achieved in several animal models using different vector systems, leading to stable transgene expression. The tight control of this expression is now an important outcome for the field of gene therapy. Such regulation is likely to be required for therapeutic applications and in some instances for safety reasons. For this purpose, several regulatable systems depending on small molecules have been developed. Among these, the tetracycline and the rapamycin dependent systems have been largely used. However, if long-term regulation of the transgene has been obtained in small animal models using these inducible systems, when translational studies were initiated in larger animals, the development of an immune response against proteins involved in transgene regulation were often observed. Such immune response was especially documented when using the TetOn tetracycline regulatable system in nonhuman primates (NHP). Humoral and destructive cellular immune responses against the transactivator involved in this regulation system were documented in a large majority of NHP leading to the complete loss of the transgene regulation and expression. This review will describe the immune responses observed in these different model systems applied for transgene regulation. Focus will be finally given on future directions in which such immune responses might be surmounted, enabling long-term transgene regulation in future clinical developments of gene transfer.
142

Identification of Disease-Associated Cryptococcal Proteins Reactive With Serum IgG From Cryptococcal Meningitis Patients

Gressler, A. Elisabeth, Volke, Daniela, Firacative, Carolina, Schnabel, Christiane L., Müller, Uwe, Krizsan, Andor, Schulze-Richter, Bianca, Brock, Matthias, Brombacher, Frank, Escandón, Patricia, Hoffmann, Ralf, Alber, Gottfried 24 March 2023 (has links)
Cryptococcus neoformans, an opportunistic fungal pathogen ubiquitously present in the environment, causes cryptococcal meningitis (CM) mainly in immunocompromised patients, such as AIDS patients. We aimed to identify disease-associated cryptococcal protein antigens targeted by the human humoral immune response. Therefore, we used sera from Colombian CM patients, with or without HIV infection, and from healthy individuals living in the same region. Serological analysis revealed increased titers of anti-cryptococcal IgG in HIV-negative CM patients, but not HIV-positive CM patients, compared to healthy controls. In contrast, titers of anti-cryptococcal IgM were not affected by CM. Furthermore, we detected pre-existing IgG and IgM antibodies even in sera from healthy individuals. The observed induction of anti-cryptococcal IgG but not IgM during CM was supported by analysis of sera from C. neoformans-infected mice. Stronger increase in IgG was found in wild type mice with high lung fungal burden compared to IL-4Ra-deficient mice showing low lung fungal burden. To identify the proteins targeted by human anti-cryptococcal IgG antibodies, we applied a quantitative 2D immunoproteome approach identifying cryptococcal protein spots preferentially recognized by sera from CM patients or healthy individuals followed by mass spectrometry analysis. Twenty-three cryptococcal proteins were recombinantly expressed and confirmed to be immunoreactive with human sera. Fourteen of them were newly described as immunoreactive proteins. Twelve proteins were classified as disease-associated antigens, based on significantly stronger immunoreactivity with sera from CM patients compared to healthy individuals. The proteins identified in our screen significantly expand the pool of cryptococcal proteins with potential for (i) development of novel anticryptococcal agents based on implications in cryptococcal virulence or survival, or (ii) development of an anti-cryptococcal vaccine, as several candidates lack homology to human proteins and are localized extracellularly. Furthermore, this study defines preexisting anti-cryptococcal immunoreactivity in healthy individuals at a molecular level, identifying target antigens recognized by sera from healthy control persons.
143

Untersuchung der humoralen adaptiven Immunantwort auf die Infektion und die Vakzinierung mit einem enteral assoziierten Erreger

Harzer, Maxi 17 May 2024 (has links)
Einleitung: Virale Infektionen gefährden global die Gesundheit von Mensch und Tier und stehen unter Beobachtung internationaler Organisationen. Die Eintrittspforte der meisten viralen Erreger sind Schleimhautoberflächen. Das Schleimhaut-assoziierte Immunsystem schützt Lebewesen lokal vor Infektionen. Daher ist das Ziel vieler Impfstoffe eine vor Infektion bzw. Erkrankung schützende Immunantwort zu stimulieren um Schleimhaut-assoziierter Erreger an der Eintrittspforte abzuwehren zu können. Um den Schutz eines Individuums oder einer Population vor solchen viralen Erkrankungen einschätzen zu können, braucht es ein belastbares einfach zu gewinnendes Korrelat. Bei streng Schleimhaut-assoziierten Erregern können Erreger-spezifische Antikörper zwar auch im Serum gefunden werden, doch korreliert die Konzentration in vielen Fällen nicht mit dem Schutz vor Infektion bzw. Erkrankung. Im Menschen wurde ein Zusammenhang zwischen der Konzentration an Antikörpern im Speichel zu denen in der Lungen- bzw. Darmschleimhaut beschrieben. Ziele der Untersuchungen: Die Untersuchungen in der Arbeit dienten zur Überprüfung der Hypothese, dass die Bestimmung neutralisierender Antikörper im Speichel von Schweinen sich zur Beurteilung des Immunstatus gegenüber streng enteral assoziierten Erregern eignet. Es wurde weiterhin die Hypothese aufgestellt, dass mit Speichelproben der enterale Immunstatus von dem des systemischen differenziert betrachtet werden kann. Tiere, Material und Methoden: Als Modellpathogen diente das Rotavirus (RV), ein be-deutender Erreger von gastrointestinalen Erkrankungen bei Säuglingen, Kleinkindern und Jungtieren. Zu Beginn der Arbeit wurde ein RV-spezifischer Virusneutralisationstest (VNT) modifiziert und für den Einsatz von Speichel, Serum und Darmschleim validiert. Von 17 individuellen Schweinen wurden die Pathogen-spezifischen neutralisierenden Titer in Serum, Speichel und Darmschleim bestimmt und die erhobenen Titer auf Korrelation zwischen den Probenmaterialien der individuellen Tiere geprüft (Vergleichsstudie). Um die stark variablen Konzentrationen an IgA (Immunglobulin A) und damit auch an neutralisierenden Antikörpern im Speichel auszugleichen, wurde die Normierung anhand von Elektrolyt- und Amylase-konzentrationen im Speichel angestrebt (Normierungsstudie). Der analysierte Datensatz basiert auf den Werten von 34 Speichelproben, die von fünf Schweinen gewonnen wurden. Abschließend wurde überprüft, ob sich die Antikörperbestimmung im Speichel dazu eignet, den Immunstatus post Vakzinierung im Schwein zu beurteilen (Immunisierungsstudie). Erstmalig wurden dafür 18 Sauen eines Bestands über einen Zeitraum von sechs Monaten während der Einführung eines bestandsspezifischen 96 RVA-Impfstoffs unter Feldbedingungen begleitet. Für die immunologische Aufarbeitung wurden mittels VNT und IFT (Immunfluoreszenztest) in Speichel- und Blutproben RV-spezifische (neutralisierende) Antikörpertiter bestimmt. Ergebnisse: Im Rahmen der Arbeit gelang es einen belastbaren RV-spezifischen VNT zu entwickeln. Die Spezifität wurde durch die Anpassung der Viruslast sowie der Proben-Virus- Inokulationszeit im Protokoll gegenüber dem Ursprungsprotokoll verbessert. Die Sensitivität wurde indirekt über den IFT bestimmt und lag in dem Bereich der IFT-Titer von 8.000 bis 40.000. Die Wiederholbarkeit für mittlere bis hohe VNT-Titer entsprach den WAOH-Empfehlungen. Vergleichsstudie: Eine signifikante Korrelation (0,69) konnte zwischen den neutralisierenden Titern im Speichel und den neutralisierenden Titern im Duodenum festgestellt werden. Die Korrelationen zwischen den neutralisierenden Titern im Speichel und denen im Darmschleim waren höher als die Korrelation zwischen den neutralisierenden Titern im Serum und denen im Darmschleim. Normierungsstudie: Bei der statistischen Auswertung des gesamten Datensatzes ergaben sich keine Hinweise auf Korrelationen zwischen den Amylase- und Elektrolytkonzentrationen und der IgA-Konzentration oder dem VNT-Titer im Speichel. Bei Ausschluss der Datensätze, in denen die IgA-Konzentration im Speichel unter 350 ng/ml lag, zeigte sich jedoch eine signifikant positive Korrelation (Korrelationskoeffizient: 0,7607) der IgA-Konzentration zu den RVC G1P[1]1- spezifischen VNT-Titern (p = 0,0014). Immunisierungsstudie: Die VNT-Titer im Serum als Korrelat zur systemischen Immunantwort und die Speichel-VNT-Titer als Korrelat zur mukosalen Immunantwort verdeutlichten in der Immunisierungsstudie die differenzierte Immunantwort auf den parenteral verabreichten Totimpfstoff. Die Grundimmunisierung erzeugte sowohl im Serum als auch im Speichel einen signifikanten VNT-Titer-Anstieg. Bei der darauffolgenden Auffrischungsimpfung war lediglich in den Serumproben ein erneuter signifikanter VNT-Titer-Anstieg zu messen. Nach Erreichen des Titer-Höhepunkts fielen die Titer im Speichel innerhalb von zwei Wochen und die im Serum in- nerhalb von drei Monaten auf Werte nahe der Ausgangstiter ab. Mittels der IFT-Untersuchungen konnte gezeigt werden, dass die Speichel-VNT-Titer eine stark positive Korrelation zu den IgA- Titern im Blut sowie die Serum-VNT-Titer zu den IgG-Titern im Blut aufweisen. Schlussfolgerungen: Im Rahmen der vorliegenden Arbeit ist es gelungen einen für alle Probenmaterialien geeigneten VNT zu etablieren. Bei Betrachtung aller drei Teilstudien ergeben sich Indizien, die die aufgestellte Hypothese unterstützen. Die Herausforderungen bei der Nutzung von Speichelproben als Diagnostikum konnten auch in dieser Arbeit aufgezeigt werden. Eine Normierung der neutralisierenden Titer im Speichel sollte weiterverfolgt werden. Möglicherweise ist die Gewinnung von Speichel aus den Unterkiefer- bzw. Unterzungendrüsen geeigneter als Diagnostikum. Zusammenfassend betrachtet, zeigen die Untersuchungen dieser Arbeit auf, dass der differenzierten Erhebung der systemischen und der mukosalen Immunantwort eine besondere Bedeutung zukommt und grundlegende Erkenntnisse zum Verständnis immunologischer Reaktionen mittels Speichel-basierter Diagnostik erlangt werden können. / Introduction: Viral infections are a global burden to human and animal health and are in the focus of international organisations. The entry sites of most viral pathogens are mucosal surfaces. The mucosa-associated immune system protects organisms locally against infections. Therefore, the goal of many vaccines is to stimulate a protective immune response against infection or disease in order to combat mucosal-associated pathogens at the site of entry. In order to assess the protection of an individual or a population against such viral diseases, a robust correlate that can be easily obtained is needed. Although pathogen-specific antibodies can be found in serum, the concentration does often not correlate with protection against infection or disease with strictly mucosa-associated pathogens. In humans, a correlation between the concentration of antibodies in saliva and those in the lung or intestinal mucosa has been described. Objectives: The investigations in this thesis aimed to prove the hypothesis that the determination of neutralising antibodies in the saliva of pigs is suitable for the assessment of the immune status against enteral associated pathogens. It was further hypothesised that saliva samples can be used to differentiate the mucosal immune status from the systemic immune status. Animals, material and methods: Rotavirus (RV), a significant pathogen of gastrointestinal diseases in infants, children and young animals, served as a model. At the beginning of the work, an RV-specific virus neutralisation Assay (VNA) was modified and validated for use with saliva, serum and intestinal mucus. Pathogen-specific neutralising titres were determined in serum, saliva and intestinal mucus from 17 individual pigs and the titres obtained were tested for correlation between the sample materials of the individual animals (comparative study). In order to compensate for the highly variable concentrations of IgA (immunoglobulin A) and thus also of neutralising antibodies in saliva, normalisation was aimed at using electrolyte and amylase concentrations in saliva (normalisation study). The analysed data set is based on the values of 34 saliva samples obtained from five pigs. Finally, it was examined whether the determination of antibodies in saliva is suitable for assessing the post-vaccination immune status in pigs (immunisation study). For the first time, 18 sows of a herd were followed over a period of six months during the introduction of a herd-specific RVA vaccine under field conditions. For immunological work-up, RV specific (neutralising) antibody titres were determined by VNA and IFA (immune fluorescence assay) in saliva and blood samples. 98 Results: In the work developing of a robust RV-specific VNA was successful. The specificity was improved by adjusting the viral load as well as the sample-virus inoculation time in the protocol compared to the original protocol. Sensitivity was determined indirectly by IFA and was in the range of IFA titres from 8,000 to 40,000. Repeatability for intermediate to high VNA titres was in line with WAOH recommendations. Comparative study: A significant correlation (0.69) was found between the neutralising titres in saliva and the neutralising titres in the duodenum. The correlations between the neutralising titres in saliva and those in intestinal mucus were higher than the correlation between the neutralising titres in serum and those in intestinal mucus. Normalisation study: Statistical analysis of the entire data set revealed no evidence of correlations between the amylase and electrolyte concentrations and the IgA concentration or the VNA titre in saliva. However, when excluding the datasets in which the salivary IgA concentration was below 350 ng/ml, there was a significant positive correlation (correlation coefficient: 0.7607) of IgA concentration to RVC G1P[1]1-specific VNA titres (p = 0.0014). Immunisation study: The serum VNA titres as a correlate of the systemic immune response and the saliva VNA titres as a correlate of the mucosal immune response illustrated the differential immune response to the parenterally administered inactivated vaccine in the immunisation study. The primary immunisation produced a significant VNA titer increase in both serum and saliva. During the subsequent booster vaccination, a renewed significant VNA titer increase was only measured in the serum samples. After reaching the titer peak, the titres in saliva dropped to values close to the initial titres within two weeks and those in serum within three months. By means of the IFA examinations, it could be shown that the salivary VNA titres showed a strong positive correlation to the IgA titres in the blood and the serum VNA titres to the IgG titres in the blood. Conclusion: Within the framework of the present work, it was possible to establish a VNA suitable for all sample materials. Considering all three sub-studies, there are indications that support the hypothesis that was established. The challenges in the use of saliva samples as a diagnostic tool could also be demonstrated in this work. A standardisation of the neutralising titres in saliva should be further pursued. It may be that the collection of saliva from the submandibular or sublingual glands is more appropriate as a diagnostic tool. In summary, the investigations of this study show that the differentiated assessment of the systemic and mucosal immune response is of particular importance and that fundamental insights into the understanding of immunological reactions can be gained by means of saliva-based diagnostics.
144

De "chólos" à "cholè" : enquête sur les origines de la notion médicale de "bile" / From "chólos" to "cholè" : an inquiry into the origins of the medical concept of "gall"

Stevanović, Divna 12 December 2011 (has links)
La notion de « bile », exprimée par le substantif χολή, représente l’un des plus importants et des plus célèbres concepts de la médecine hippocratique, inséparable dans la pensée moderne de la fameuse théorie humorale. Au premier abord, les choses semblent donc claires. Cependant, lorsqu’on se plonge dans la lecture des écrits hippocratiques, la notion de cholè s’avère moins simple et évidente. Notre analyse des textes hippocratiques montre, en effet, que la cholè diffère d’un traité à l’autre et que chaque auteur hippocratique élabore sa propre notion de cholè. Nous nous sommes posé alors la question de l’origine de ce concept médical, ainsi que de l’origine de son cadre, qui est la théorie humorale. Notre quête des origines nous a amenée jusqu’aux idées homérique de chólos et aristophanique de cholè, qui se présentent toutes les deux comme fondamentalement différentes de l’idée médicale de cholè, unissant en elles-mêmes les notions de substance et d’état d’esprit. C’est justement cet écart entre les concepts non-médicaux et les concepts médicaux qui nous a intéressée au plus haut point, car il permet de voir comment les médecins hippocratiques élaborent leurs idées et leur discours. L’essentiel de notre travail consiste, donc, en un examen approfondi des procédés par lesquels les hippocratiques s’approprient des idées non-médicales : ce qu’ils retranchent, ce qu’ils rajoutent et ce qu’ils remanient. Nous espérons ainsi mettre en évidence les chemins par lesquels passe la pensée médicale ancienne, dans son processus d’émancipation de la culture traditionnelle, mais aussi des autres « sciences » de l’époque, telle que la philosophie. / The notion of « gall », expressed by the noun χολή, is one of the most important as well as the most celebrated concepts of the hippocratic medicine, inseparable for the modern mind from the humoral theory. At first sight then, the idea of « gall » seems fairly obvious. However, reading hippocratic treatises in detail, one realizes that the notion of cholè turns out to be far more complex and intricate than expected. Our analysis of the most relevant hippocratic texts shows indeed that the concept of cholè varies according to the texts involved, as every author tends to develop his own concept of cholè. We tried to find out whether the complex nature of the medical concept known as cholè could be elucidated by a survey of its origins, and a survey of the origins of the humoral system as a whole. Our search for the origins of cholè has led us to the Homeric concept of chólos and to the Aristophanic concept of cholè. The prerequisites of both notions conspicuously differ from the medical concept of cholè, because they unite the substance with a state of mind. This discrepancy between medical and non-medical concepts was of utmost importance for us, since it helped to understand how hippocratic authors developed their ideas and their discourse. The main asset of our work consists, therefore, in an in-depth analysis of the ways in which hippocratic authors take over some non-medical ideas to frame concepts of their own : what are the components they cut out, add or modify. Our goal is to show how ancient medical thought proceeds, in its endeavour to emancipate itself from the tradition as well as from the other contemporary “sciences”, as philosophy.
145

Efeitos do treinamento físico aeróbico sobre o remodelamento do ventrículo esquerdo e sua correlação com a ativação neuro-humoral em pacientes com infarto agudo do miocárdio / Effects of aerobic exercise training on left ventricular remodeling and its correlation with neurohumoral activation in patients with acute myocardial infarction.

Santi, Giovani Luiz de 13 April 2012 (has links)
A literatura mostra um número substancial de trabalhos que descrevem a influência do treinamento físico sobre o remodelamento ventricular em pacientes no contexto do pós-infarto agudo do miocárdio (IAM). Entretanto, essas publicações têm apresentado resultados conflitantes. O presente estudo teve como objetivo avaliar os efeitos do treinamento físico aeróbico de moderada intensidade, realizado em pacientes pós-IAM, sobre o remodelamento ventricular, e sua correlação com a ativação neuro-humoral. Foram avaliados 14 pacientes, de ambos os gêneros, idade média de 55,1 ± 10,8 anos, acometidos por um único IAM de parede anterior, divididos em dois grupos: grupo treinado (GT) (n=07) e grupo controle (GC) (n=07). O período de seguimento para esse estudo foi de 12 semanas. Antes e após o período de seguimento, os pacientes realizaram exames laboratoriais, avaliação antropométrica, coleta da freqüência cardíaca (FC) de repouso, teste cardiopulmonar e ressonância magnética cardíaca. O GT realizou treinamento físico aeróbico supervisionado em esteira ergométrica, três vezes por semana, com intensidade definida pela FC atingida no limiar de anaerobiose ventilatório. A análise estatística foi realizada através do teste não paramétrico da Soma de Postos de Wilcoxon (análise intragrupo) e teste não paramétrico de Mann-Whitney (análise intergrupo), com nível de significância de 5%. Não houve alteração estatisticamente significante no peso, índice de massa corporal, perfil lipídico e glicemia de jejum pré e pós-intervenção tanto no GC quanto no GT. Houve redução estatisticamente significante da FC de repouso no GT, sem alteração no GC. Observou-se aumento estatisticamente significante do consumo de oxigênio no limiar de anaerobiose e no pico do esforço, bem como, no incremento do pulso de oxigênio apenas no GT. Houve redução estatisticamente significante do volume diastólico final, e tendência a significância no volume sistólico final do GC. Não se observou mudanças estatisticamente significantes nos volumes cavitários pré e pós-intervenção no GT. Não houve mudança estatisticamente significante na fração de ejeção tanto no GT quanto no GC. Houve redução estatisticamente significativa do fragmento N-terminal do proBNP na condição basal e no pico do esforço tanto no GT quanto no GC. Concluímos que o treinamento físico aeróbico, de moderada intensidade, propiciou um aumento da aptidão física e cardiorrespiratória, manutenção dos volumes cavitários e da função cardíaca, e comportamento satisfatório do status neuro-humoral no GT durante o período do estudo. / The literature shows a substantial number of studies describing the influence of physical training on ventricular remodeling in patients in the context of post-acute myocardial infarction (AMI). However, these publications have produced conflicting results. The present study was to evaluate the effects of aerobic physical training of moderate intensity, performed in patients after MI on ventricular remodeling, and its correlation with neurohumoral activation. We evaluated 14 patients of both genders, mean age 55.1 ± 10.8 years, affected by a single anterior wall AMI were divided into two groups: trained group (TG) (n = 07) and control group ( CG) (n = 07). The follow-up period for this study was 12 weeks. Before and after follow-up period, patients underwent laboratory tests, anthropometric measurements, collection of heart rate (HR) at rest, cardiopulmonary exercise testing and cardiac MRI. The TG performed supervised aerobic exercise training on a treadmill three times a week, with intensity defined by HR reached at ventilatory anaerobic threshold. Statistical analysis was performed using the nonparametric Wilcoxon Sum of stations (intragroup analysis) and nonparametric Mann-Whitney test (intergroup analysis), with a significance level of 5%. There was no statistically significant change in weight, body mass index, lipid profile and fasting glucose and post-intervention in both the CG and TG. There was a statistically significant reduction in resting HR in TG, no change in CG. There was a statistically significant increase in oxygen uptake in the anaerobic threshold and peak effort, as well as an increase in oxygen pulse only in the TG. There was a statistically significant reduction in end-diastolic volume, and a tendency to significance in end-systolic volume of the CG. There was no statistically significant changes in cavity volume before and after intervention in TG. There was no statistically significant change in ejection fraction in both the TG and GC. There was a statistically significant reduction of the N-terminal fragment of proBNP at baseline and at peak exercise in both the TG and CG. We conclude that aerobic exercise training of moderate intensity, provided an increase in cardiorespiratory fitness and, maintenance of the cavity volume and cardiac function, and satisfactory performance of the neuro-humoral status in TG during the study period.
146

Identificação de marcadores genéticos associados às imunidades celular, humoral e aos status clínico e de infecção natural pela Leishmania (Leishmania) infantum em cães / Identification of genetic markers associated to clinical, antibody and cellmediated reponses to natural Leishmania (Leishmania) infantum infection in dogs

Batista, Luís Fábio da Silva 22 March 2016 (has links)
A infecção de cães pela Leishmania (Leishmania) infantum resulta em um espectro de manifestações imunopatológicas que dependem da interação parasito hospedeiro e são definidas por fatores ambientais e pela genética do hospedeiro. Apesar disso, a imunogenética da leishmaniose visceral canina (LVC) permanece inexplorada. Nós realizamos diagnóstico laboratorial, clínico, ensaio de linfoproliferação (LPA), quantificação de citocinas, teste de hipersensibilidade tardia à leishmanina (LST), quantificação de IgA, IgE, IgG, IgM anti L. (L. ) infantum, IgG anti saliva de flebotomíneo e genotipagem ampla afim de identificar polimorfismos de nucleotídeo único (SNPs) associados aos diferentes perfis de imunidades celular, humoral, resposta clínica e status de infecção em cães de área endêmica, utilizando modelo de componente de variância (EMMAX). O efeito de estrutura da amostra foi controlado em todas as análises. A presença ou ausência de infecção pela L. (L. ) infantum foi associado a regiões contendo os genes PRGR_CANFA, RAB38, NOX4, PRKCI e SMAD7, IL1RA, IL12A_CANFA relacionados à ativação de fagócitos, mecanismos microbicidas, sobrevivência intracelular de patógenos e resposta pró inflamatória; a resposta clínica foi associada a regiões contendo os genes CATA_CANFA, LIAS, IL17A e IL17F relacionados à proteção contra danos do estresse oxidativo e indução de resposta pró inflamatória; o resultado LST+ foi associado à resposta Th1, controle da infecção mas não preveniu a manifestação de sinais clínicos, enquanto o LST- foi associado à resposta Treg e aumento do parasitismo. O resultado do LST foi associado a regiões contendo os genes MEP1B, PTPRM, TLN1, TGFBR1, ITGA9, EPCAM e CALM1 envolvidos com maturação de fagócitos, migração e adesão de leucócitos, estabilidade da sinapse imunológica, diferenciação e proliferação de linfócitos. A linfoproliferação foi dependente da carga parasitária e associada a regiões contendo os genes FOCAD, PIAS2, SMAD2 e IL6R envolvidos com supressão tumoral e diferenciação de linfócitos Th17 ou Treg; o aumento dos níveis de IgA, IgE e IgG anti L. (L. ) infantum foi associado à LVC sintomática enquanto o de IgG anti saliva de Lutzomyia longipalpis foi associado à exposição e infecção assintomática. Quanto à resposta de IgM, foram identificados SNPs nos genes NXN e SH3BP5 relacionados com inibição do crescimento, diferenciação e ativação de linfócitos B e vias de sinalização de TLR4 e TLR9; para IgG anti - L. (L. ) infantum foram identificadas regiões contendo os genes IL17RB, SH2B3 e replicação do loci de susceptibilidade NOX4, RAB38, CTSC envolvidos com linfopoiese, citocinese, resposta pró inflamatória, mecanismos microbicidas, sobrevivência intracelular de Leishmania; os níveis de IgA foram associados a regiões contendo os genes LIN28A e MAFB implicados na predisposição à nefropatia glomerular, já os níveis de IgG anti saliva de Lu. longipalpis foram associados a regiões contendo os genes ERBB2IP, CD180, RAB7A_CANFA, FOXP1, RUNX1, SOD1, Q3HTU8_CANFA, IFNAR1, IFNAR2 e IFNGR2 envolvidos com supressão celular, produção de imunoglobulina via TLR4 e sobrevivência intracelular de Leishmania. Esses resultados apontam regiões cromossômicas úteis para a elucidação da resposta à infecção por L. (L. ) infantum em cães e alvos potenciais para estudos funcionais, estratégias profiláticas e terapêuticas / Leishmania (Leishmania) infantum infection in dogs leads to a range of immunopathological responses, which depend on a parasite - host interaction and are defined by environmental factors and genetic of host. Neverthless, immunogenetic of the canine leishmaniasis (CanL) remains unexplored. We performed diagnosis and clinical evaluation, lymphoproliferation assay (LPA), leishmanin skin test (LST), quantification of cytokine, anti-L. (L. ) infantum IgA, IgE, IgG, IgM, anti- sandfly saliva IgG levels and genome wide association scan of 110.165 SNPs (GWAS) in order to indentify loci associated to clinical, antibody, cell-mediated responses and status of infection in 189 dogs, employng a expedited efficient mix model of association (EMMAX). Control of stratification effects due to sample structure was evideced by the low inflation factors. Status of infection was associated to SNPs in linkage desequilibrium (LD) with PRGR_CANFA, RAB38, NOX4, PRKCI and in the neighborhood of SMAD7, IL1RA, IL12A_CANFA genes related to phagocyte maturation, killing of pathogens and proinflamatory response; clinical outcome was associated to CATA_CANFA, LIAS, IL17A, IL17F loci involved in prevention of oxidative burst mediated injury and proinflamatory response; LST+ was associated to Th1 response although it has not prevented symptoms, whereas LST- was associated to Treg response and enhanced parasite load. Overall, LST response was associated to MEP1B, PTPRM, TLN1, TGFBR1, ITGA9, EPCAM e CALM1 loci committed to phagocyte maturation, leukocyte adhesion and migration, stability in immunological synapse, lymphocyte diferenciation and proliferation. Lymphocyte proliferation was rely on parasit burden and associated to FOCAD, PIAS2 loci in the neighborhood of SMAD2 e IL6R genes, wich are implicated in tumor supression and Treg/Th17 decision; Increased levels of anti-L. (L. ) infantum IgA, IgE, IgG were observed in severity of CanL. In contrast, anti- sandfly saliva IgG was enhenced in asymptomatic dogs. IgM response was associated to NXN e SH3BP5 loci related to fate, growing and activation of B cells; anti-L. (L. ) infantum IgG levels was associated to region containing IL17RB, SH2B3 and replication of NOX4, RAB38, CTSC suscptibility loci involved in proinflamatory response, microbicidal activity, lymphopoiesis and cytokinesis; IgA levels were associated to SNPs on LIN28A and MAFB, wich are implicated glomerular nephropathy, whereas anti-sandfly saliva IgG levels were associated to ERBB2IP, CD180, RAB7A_CANFA, FOXP1, RUNX1, SOD1, Q3HTU8_CANFA, IFNAR1, IFNAR2 e IFNGR2 loci, wich are related to supression of inflamation, antibody response through the TLR4 pathway and survival of intracellular pathogens. These findins provide insights for responses to L. (L. ) infantum infection and point to potential targets for functional investigations, therapeutic and prophylactic strategies
147

Identificação de marcadores genéticos associados às imunidades celular, humoral e aos status clínico e de infecção natural pela Leishmania (Leishmania) infantum em cães / Identification of genetic markers associated to clinical, antibody and cellmediated reponses to natural Leishmania (Leishmania) infantum infection in dogs

Luís Fábio da Silva Batista 22 March 2016 (has links)
A infecção de cães pela Leishmania (Leishmania) infantum resulta em um espectro de manifestações imunopatológicas que dependem da interação parasito hospedeiro e são definidas por fatores ambientais e pela genética do hospedeiro. Apesar disso, a imunogenética da leishmaniose visceral canina (LVC) permanece inexplorada. Nós realizamos diagnóstico laboratorial, clínico, ensaio de linfoproliferação (LPA), quantificação de citocinas, teste de hipersensibilidade tardia à leishmanina (LST), quantificação de IgA, IgE, IgG, IgM anti L. (L. ) infantum, IgG anti saliva de flebotomíneo e genotipagem ampla afim de identificar polimorfismos de nucleotídeo único (SNPs) associados aos diferentes perfis de imunidades celular, humoral, resposta clínica e status de infecção em cães de área endêmica, utilizando modelo de componente de variância (EMMAX). O efeito de estrutura da amostra foi controlado em todas as análises. A presença ou ausência de infecção pela L. (L. ) infantum foi associado a regiões contendo os genes PRGR_CANFA, RAB38, NOX4, PRKCI e SMAD7, IL1RA, IL12A_CANFA relacionados à ativação de fagócitos, mecanismos microbicidas, sobrevivência intracelular de patógenos e resposta pró inflamatória; a resposta clínica foi associada a regiões contendo os genes CATA_CANFA, LIAS, IL17A e IL17F relacionados à proteção contra danos do estresse oxidativo e indução de resposta pró inflamatória; o resultado LST+ foi associado à resposta Th1, controle da infecção mas não preveniu a manifestação de sinais clínicos, enquanto o LST- foi associado à resposta Treg e aumento do parasitismo. O resultado do LST foi associado a regiões contendo os genes MEP1B, PTPRM, TLN1, TGFBR1, ITGA9, EPCAM e CALM1 envolvidos com maturação de fagócitos, migração e adesão de leucócitos, estabilidade da sinapse imunológica, diferenciação e proliferação de linfócitos. A linfoproliferação foi dependente da carga parasitária e associada a regiões contendo os genes FOCAD, PIAS2, SMAD2 e IL6R envolvidos com supressão tumoral e diferenciação de linfócitos Th17 ou Treg; o aumento dos níveis de IgA, IgE e IgG anti L. (L. ) infantum foi associado à LVC sintomática enquanto o de IgG anti saliva de Lutzomyia longipalpis foi associado à exposição e infecção assintomática. Quanto à resposta de IgM, foram identificados SNPs nos genes NXN e SH3BP5 relacionados com inibição do crescimento, diferenciação e ativação de linfócitos B e vias de sinalização de TLR4 e TLR9; para IgG anti - L. (L. ) infantum foram identificadas regiões contendo os genes IL17RB, SH2B3 e replicação do loci de susceptibilidade NOX4, RAB38, CTSC envolvidos com linfopoiese, citocinese, resposta pró inflamatória, mecanismos microbicidas, sobrevivência intracelular de Leishmania; os níveis de IgA foram associados a regiões contendo os genes LIN28A e MAFB implicados na predisposição à nefropatia glomerular, já os níveis de IgG anti saliva de Lu. longipalpis foram associados a regiões contendo os genes ERBB2IP, CD180, RAB7A_CANFA, FOXP1, RUNX1, SOD1, Q3HTU8_CANFA, IFNAR1, IFNAR2 e IFNGR2 envolvidos com supressão celular, produção de imunoglobulina via TLR4 e sobrevivência intracelular de Leishmania. Esses resultados apontam regiões cromossômicas úteis para a elucidação da resposta à infecção por L. (L. ) infantum em cães e alvos potenciais para estudos funcionais, estratégias profiláticas e terapêuticas / Leishmania (Leishmania) infantum infection in dogs leads to a range of immunopathological responses, which depend on a parasite - host interaction and are defined by environmental factors and genetic of host. Neverthless, immunogenetic of the canine leishmaniasis (CanL) remains unexplored. We performed diagnosis and clinical evaluation, lymphoproliferation assay (LPA), leishmanin skin test (LST), quantification of cytokine, anti-L. (L. ) infantum IgA, IgE, IgG, IgM, anti- sandfly saliva IgG levels and genome wide association scan of 110.165 SNPs (GWAS) in order to indentify loci associated to clinical, antibody, cell-mediated responses and status of infection in 189 dogs, employng a expedited efficient mix model of association (EMMAX). Control of stratification effects due to sample structure was evideced by the low inflation factors. Status of infection was associated to SNPs in linkage desequilibrium (LD) with PRGR_CANFA, RAB38, NOX4, PRKCI and in the neighborhood of SMAD7, IL1RA, IL12A_CANFA genes related to phagocyte maturation, killing of pathogens and proinflamatory response; clinical outcome was associated to CATA_CANFA, LIAS, IL17A, IL17F loci involved in prevention of oxidative burst mediated injury and proinflamatory response; LST+ was associated to Th1 response although it has not prevented symptoms, whereas LST- was associated to Treg response and enhanced parasite load. Overall, LST response was associated to MEP1B, PTPRM, TLN1, TGFBR1, ITGA9, EPCAM e CALM1 loci committed to phagocyte maturation, leukocyte adhesion and migration, stability in immunological synapse, lymphocyte diferenciation and proliferation. Lymphocyte proliferation was rely on parasit burden and associated to FOCAD, PIAS2 loci in the neighborhood of SMAD2 e IL6R genes, wich are implicated in tumor supression and Treg/Th17 decision; Increased levels of anti-L. (L. ) infantum IgA, IgE, IgG were observed in severity of CanL. In contrast, anti- sandfly saliva IgG was enhenced in asymptomatic dogs. IgM response was associated to NXN e SH3BP5 loci related to fate, growing and activation of B cells; anti-L. (L. ) infantum IgG levels was associated to region containing IL17RB, SH2B3 and replication of NOX4, RAB38, CTSC suscptibility loci involved in proinflamatory response, microbicidal activity, lymphopoiesis and cytokinesis; IgA levels were associated to SNPs on LIN28A and MAFB, wich are implicated glomerular nephropathy, whereas anti-sandfly saliva IgG levels were associated to ERBB2IP, CD180, RAB7A_CANFA, FOXP1, RUNX1, SOD1, Q3HTU8_CANFA, IFNAR1, IFNAR2 e IFNGR2 loci, wich are related to supression of inflamation, antibody response through the TLR4 pathway and survival of intracellular pathogens. These findins provide insights for responses to L. (L. ) infantum infection and point to potential targets for functional investigations, therapeutic and prophylactic strategies
148

The development of live vectored vaccines targeting the alpha-toxin of Clostridium perfringens for the prevention of necrotic enteritis in poultry

Gatsos, Xenia, xgatsos@optusnet.com.au January 2007 (has links)
The ƒÑ-toxin of Clostridium perfringens is a toxin involved in numerous diseases of humans and agriculturally important animals. One of these diseases is necrotic enteritis (NE), a sporadic enteric disease which affects avian species world-wide. This study involved the inactivation of alpha-toxin (ƒÑ-toxin) for use as a potential vaccine candidate to combat NE in chickens, and other diseases caused by C. perfringens type A. During the course of this research a number of ƒÑ-toxin recombinant proteins were developed through molecular inactivation of the ƒÑ-toxin gene, plc. Proteins plc316 and plc204 were developed by the deletion of the first three and seven ƒÑ-helices of the N-terminal domain respectively. These deletions resulted in proteins which were unstable in solution, constantly aggregated into insoluble masses and elicited lower overall antibody responses when administered to mice. A third protein, plcInv3 was developed from the deletion of part of the catalytic domain of the ƒÑ-toxin. PlcInv3 was highly soluble and upon immunisation of mice elicited a significant antibody response which was also capable of protecting mice against a live challenge of C. perfringens. The fourth and final protein developed was plc104. The smallest of the recombinant ƒÑ-toxin proteins, it consisted entirely of the C-terminal domain of ƒÑ-toxin. Its small size did not affect its ability to induce a strong antibody response when administered to mice, the antibodies of which were also protective during a challenge with C. perfringens. STM1, an attenuated strain of S. Typhimurium was used in the development of a vectored vaccine for the expression and oral delivery of plcInv3 and plc104 within the mouse host. The proteins were expressed within STM1 from expression plasmids containing the in vivo inducible promoters PhtrA and PpagC. A measurable humoral immune response against ƒÑ-toxin was absent following three oral vaccinations with the vectored vaccines, although, cytokine profiling of splenocytes from vaccinated mice revealed an increase in the number of interleukin-4 (IL-4)secreting cells and the lack of interferon-gamma (IFN-ƒ×) secreting cells. This indicated the stimulation of a T-helper type 2 (TH2) immune response which also lead to partial protection against a live C. perfringens challenge. This study demonstrates the feasibility of using STM1 as a carrier for the in vivo expression of the C. perfringens ƒÑ-toxin recombinant proteins plcInv3 and plc104. It is the first study to express C. perfringens antigens within an attenuated strain of S. Typhimurium, STM1.The partial protection of mice immunised with these vaccines indicates there is potential for this vectored vaccine system to be used in the protection of diseases caused by the ƒÑ-toxin of C. perfringens.
149

The immune-modulating activity of Artemisia afra

Kriel, Yusra January 2010 (has links)
<p>This study shows that herbs can be effectively screened for potiential bio-activity using in vitro methods. Further studies will be needed to better explore Artemisia afra&rsquo / s effect on immunoregulation, particularly long term effects of the herb on the immune system and its effect on other disease states.</p>
150

Protein based approaches to understand and prevent contagious bovine pleuropneumonia

Hamsten, Carl January 2009 (has links)
Contagious bovine pleuropneumonia (CBPP) is a severe infectious disease caused by Mycoplasma mycoides subsp. mycoides small colony type (M. mycoides SC) and is a vast problem in Africa. Current CBPP prevention is based on attenuated live strain vaccines, but these are limited by factors such as short-term immunity, cold-chain dependence and retained virulence. CBPP can be diagnosed using post-mortem examination, identification of the agent using culture and PCR based methods as well as serological diagnostic methods, but the latter are generally not sensitive enough and there is also demand for an inexpensive, pen side field test.The research presented in this thesis was focused on using recombinantly expressed surface proteins from M. mycoides SC to characterize humoral immune responses to CBPP. Thereby candidate proteins to be used in development of serological diagnostic methods and possibly subunit vaccines could be identified. As a first step, five putative variable surface proteins of M. mycoides SC were expressed and purified from E. coli in Paper I. These proteins were analyzed using immunoblotting techniques and results showed that one protein, MSC_0364, was variably expressed on the surface of M. mycoides SC in vitro. Paper II presents expanded efforts including cloning and expression of 64 recombinant surface proteins and an assay for high throughput analysis of protein-specific IgG, IgA and IgM titers in hundreds of sera using a bead-based screening assay. The assay was evaluated by protein-specific inhibition experiments, comparisons to Western blotting and monitoring of immune responses over time in a study with sera taken from eight animals over 293 days from a previous vaccine trial.Papers III and IV present applications using the recombinant proteins and bead-based screening assay wherein proteins for diagnostic and vaccine development were identified. In Paper III, the assay was used to screen 61 proteins using well-characterized serum samples from cattle with CBPP and healthy controls, resulting in selection of eight proteins suitable for diagnostic use. These proteins were combined and evaluated in a proof-of-concept ELISA with a discriminative power that enabled 96% correct classification of sera from CBPP-affected and CBPP-free bovines. Paper IV reports the results and protein-specific analyses of a vaccine trial using the recombinant putative variable surface proteins presented in Paper I as a subunit vaccine. The vaccine conferred no protection, but a weak vaccine response could not be excluded as the cause of failure. In an effort to identity other protein candidates to be used in a subunit vaccine, protein-specific analysis of humoral immune responses elicited by the currently approved live strain vaccine, T1/44, were investigated. Here, five proteins with high IgG titers associated to immunity were identified: LppQ, MSC_02714, MSC_0136, MSC_0079 and MSC_0431. These proteins may be important in the development of a novel subunit vaccine against CBPP. / QC 20100719

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