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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.
81

I never thought I'd be that strong : The effect on the professional helper when working with assessment and treatment of child sexual abuse in South Africa.

Furingsten, Sara, Wistrand, Madelene January 2006 (has links)
<p>The aim of this study was to explore how professional helpers, who work at a clinic in South Africa, experience and are affected by their work in the assessment and treatment of child sexual abuse. Twelve professional helpers were interviewed using a qualitative, semi-structured interview. The analysis of the interviews resulted in five overall categories. These are; The work with children; Pressures at work; Motivation for doing the job; Influences on a personal level and Coping strategies. Our study reveals that all of the professionals are influenced by their work but most of them not to the extent that they cannot enjoy life. The people who, apart from working with abused children, also work within management seem more affected by their work. Thus one of the conclusions is that the professionals are influenced by the entire work situation and not only by the clients that they meet. Another conclusion is that the work with sexually abused children has an effect on the professionals'private lives and that boundaries between work and private life are hard to keep.</p>
82

The ‘Helper’ Phenotype: A Symbiotic Interaction Between Prochlorococcus and Hydrogen Peroxide Scavenging Microorganisms

Morris, James Jeffrey 01 May 2011 (has links)
The unicellular cyanobacterium Prochlorococcus is the numerically dominant photosynthetic organism throughout the temperate and tropical open oceans, but it is difficult to grow in pure cultures. We developed a system for rendering spontaneous streptomycin-resistant mutants of Prochlorococcus axenic by diluting them to extinction in the presence of “helper” heterotrophic bacteria, allowing them to grow to high cell concentrations, and then killing the helpers with streptomycin. Using axenic strains obtained in this fashion, we demonstrated that Prochlorococcus experiences a number of growth defects in dilute axenic culture, including reduced growth rate, inability to form colonies on solid media, and higher incidence of mortality (i.e., catastrophic failure of liquid cultures). These defects were eliminated when Prochlorococcus was grown in co-culture with a phylogenetically diverse array of helper bacteria. The primary mechanism of helping was enzymatic removal of hydrogen peroxide (HOOH) from the culture medium. Axenic Prochlorococcus cultures were profoundly sensitive to HOOH additions in comparison with reported tolerance levels for all other wild-type aerobic bacteria, but in co-culture their resistance was similar to that of the helpers. Neither is dependence on helpers limited to the laboratory. Sterile-filtered seawater exposed to sunlight accumulated enough HOOH in 24h to kill ecologically relevant cell concentrations of Prochlorococcus. We also refined a method for delivering HOOH at a defined, steady rate using the buffer HEPES to more accurately simulate the steady accumulation of HOOH in natural waters. Even at the lowest production rates that could sustain the in situ HOOH concentration in the ocean, HEPES-generated HOOH was lethal to Prochlorococcus; again, co-culture with helpers prevented this effect. We speculate on the ecological consequences of Prochlorococcus’ dependency on other organisms for survival, as well as the evolutionary forces that have led to this lack of self-sufficiency.
83

Initiation of Autoimmunity in Experimental Autoimmune Encephalomyelitis

Isaksson, Magnus January 2012 (has links)
The events that trigger an autoimmune disease remain largely unknown. To study these events animal models are necessary because symptoms of autoimmune diseases are preceded by a long asymptomatic period in humans. Experimental autoimmune encephalomyelitis (EAE) is the best characterized model for cell mediated autoimmunity and an animal model for the human disease multiple sclerosis. EAE is induced in rodents by immunization with myelin antigens (Ags) together with adjuvants. After immunization, T cells are primed in the periphery by Ag presenting cells and subsequently invade the central nervous system where they mediate parenchymal inflammation, resulting in demyelination and clinical symptoms of an ascending paralysis. It is now generally recognised that the main cell type mediating EAE is the T helper type 17 (Th17) cell. Tolerance to EAE can be attained by DNA vaccination, but how the immune response against the myelin Ags is abrogated after DNA vaccination is not known. By employing short interfering RNA technology, induction of the innate immune signalling molecule interferon (IFN) -β was found to be necessary for the protective effect of DNA vaccination in EAE. In addition, DNA vaccination inhibited subsequent autoimmune Th17 cell responses. The Toll-like receptors (TLRs) of the innate immune system have evolved to recognise conserved molecular structures on microbes and signalling through them almost exclusively converge on the molecule MyD88. Signalling via MyD88 was found to be required for induction of EAE since mice deficient in this molecule did not develop disease. Upstream signalling via TLR4 and TLR9 had tolerogenic properties. In studies of Ag presentation in EAE, two major subtypes of dendritic cells (DCs) were examined. Plasmacytoid DCs were found to have a promoting role in the induction of EAE, partly via type 1 IFNs. Myeloid DCs had a redundant role in the induction phase of EAE, neither disease severity nor encephalitogenic Th17 responses were affected by their absence during priming. These studies further demonstrate that the cells and molecules of the innate immune system exhibit a crucial role in controlling the adaptive immune system which mediates tissue damage in autoimmune diseases.
84

I never thought I'd be that strong : The effect on the professional helper when working with assessment and treatment of child sexual abuse in South Africa.

Furingsten, Sara, Wistrand, Madelene January 2006 (has links)
The aim of this study was to explore how professional helpers, who work at a clinic in South Africa, experience and are affected by their work in the assessment and treatment of child sexual abuse. Twelve professional helpers were interviewed using a qualitative, semi-structured interview. The analysis of the interviews resulted in five overall categories. These are; The work with children; Pressures at work; Motivation for doing the job; Influences on a personal level and Coping strategies. Our study reveals that all of the professionals are influenced by their work but most of them not to the extent that they cannot enjoy life. The people who, apart from working with abused children, also work within management seem more affected by their work. Thus one of the conclusions is that the professionals are influenced by the entire work situation and not only by the clients that they meet. Another conclusion is that the work with sexually abused children has an effect on the professionals'private lives and that boundaries between work and private life are hard to keep.
85

Impact of mycorrhiza helper bacterium Streptomyces sp. AcH 505 on the genetic and physiuological regulation in oaks associated to pathogenic and symbiotic fungi

Kurth, Florence 14 September 2015 (has links) (PDF)
This thesis was performed within the research project “TrophinOak”, which addresses the impact of multitrophic interactions on the pedunculate oak (Quercus robur) clone DF159. In this frame, the present work focuses on the genetic and physiological mechanisms ruling the interaction of the mycorrhiza helper bacterium (MHB) Streptomyces sp. AcH 505 with microcuttings of DF159 either alone or in presence of the ectomycorrhizal fungus Piloderma croceum or the fungal leaf pathogen oak powdery mildew Microsphaera alphitoides. The work consists of 3 chapters. Chapter 1 characterises the growth of AcH 505 and P. croceum in a soil-based culture system used within the TrophinOak project. Besides the establishment and evaluation of quantification methods of these microorganisms by quantitative real-time PCR, the impact of the soil microbial community and the oak on the bacterium-fungus interaction was investigated, and AcH 505 and P. croceum were visualized by scanning electron microscopy. It was observed that the presence of the soil microorganisms and the oak both affect the bacterium-fungus interaction, and that P. croceum enhances the growth of AcH 505. Chapter 2 presents a study with the oak, AcH 505 and the EM fungus P. croceum, enabling to disentangle the direct effect of the MHB on the oak from the indirect one via the EM symbiosis. The used approach was transcriptomic based on RNA sequencing. It was shown that i) differential gene expression occurred between root and the distant leaf tissues (local vs. systemic effects), different developmental stages and treatments, suggesting that oak specifically coordinates its gene expression patterns, and ii) that genes related to plant growth, defence and DNA modification were dominant among the differential expressed genes, suggesting that these processes play essential roles in both symbiotic interactions investigated. Chapter 3 represents a second transcriptome study, addressing how AcH 505 suppresses powdery mildew infection in oak by analysing RNA Sequencing data from singly- and coinoculated oaks. This study combined the systemic impact of the root associated bacterium with local effects of the leaf pathogen, thereby linking belowground and aboveground interactions. Systemic defence response is induced by the bacterium and further enhanced upon pathogen challenge, suggesting that on the leaf level, some bacterial effectors are recognized as harmful for the plant.
86

Immunological Studies using Human and Canine Model Disorders / Immunologiska studier av modellsjukdomar i människa och hund

Ahlgren, Kerstin M. January 2011 (has links)
The studies presented in this thesis focus on human and canine models for autoimmune disease, with the main aim to gain new knowledge about disease mechanisms and to further evaluate the dog as a model for autoimmune disease. Autoimmune Polyendocrine Syndrome type 1 (APS-1) is a hereditary human multiorgan disease caused by mutations in the autoimmune regulator (AIRE) gene. Hallmarks of APS-1 are chronic mucocutaneous candidiasis caused by Candida albicans, together with the autoimmune endocrine disorders hypoparathyroidism and adrenocortical failure. Many human diseases have an equivalent disease in dogs. Because humans share environment, and in part life style with the dogs they provide an interesting model for further genetic studies. Immune responses to Candida albicans in APS-1 patients displayed an increased secretion of the proinflammatory cytokine IL-17A and similar results were also found in AIRE deficient mice. Anticytokine autoantibodies to IL-17A, IL-17F and IL-22 were detected in APS-1 patients, and a radioligand binding assay for measuring these autoantibodies was developed and evaluated. In the canine studies we investigated whether canine diabetes mellitus could serve as a model for human autoimmune diabetes mellitus. Furthermore, we investigated type I IFN responses in Nova Scotia duck tolling retriever dogs with a systemic autoimmune disease resembling human SLE. Four assays were used in search for signs of humoral autoimmunity in diabetic dogs. However, no evidence for a type 1 diabetes-like phenotype in dogs was found. Sera from Nova Scotia duck tolling retrievers suffering from steroid-responsive meningitis arteritis elicited an increased expression of IFN-inducible genes in the canine MDCK cell line. This suggests that these dogs have an IFN signature, as seen in human SLE.
87

Régulation immunitaire, angiogenèse et homéostasie tissulaire au cours des vascularites des gros vaisseaux / Regulation of immune response, angiogenesis and tissue repair in large vessel vasculitis

Desbois, Anne-Claire 11 October 2017 (has links)
Les vascularites des gros vaisseaux comprennent principalement la maladie de Takayasu et l'artérite à cellules géantes. Elles sont caractérisées par des lésions inflammatoires artérielles, associées à une néo-vascularisation adventitielle importante, une désorganisation architecturale de la paroi artérielle et des lésions fibrotiques, affectant l’aorte et ses principales branches. Ces maladies sont caractérisées par des réponses lymphocytaires Th1 et Th17 excessives et dérégulées. Actuellement, les mécanismes régulant la différenciation lymphocytaire, la réponse endothéliale et l’homéostasie tissulaire en contexte d’inflammation artérielle chronique ne sont pas suffisamment connus. Dans la 1ère partie de nos travaux, nous avons étudié le rôle de l’IL-33, cytokine sécrétée par les cellules endothéliales en cas de nécrose tissulaire, surexprimée dans les vascularites des gros vaisseaux et impliquée dans la régulation de la réponse immune. Nous avons mis en évidence le rôle immunomodulateur de l’IL-33 dans les vascularites des gros vaisseaux. Cette cytokine favorise en effet directement une différenciation Th2 et une augmentation des lymphocytes T régulateurs (Treg). L’IL-33 exerce également son action immunorégulatrice par le biais des mastocytes qui favorisent également une augmentation majeure des Treg en présence d’IL-33, probablement grâce à la sécrétion d’IL-2, essentielle à la survie et l’expansion des Treg et la sécrétion d’indoléamine 2,3 dioxygénase (IDO). L’IL-33 et les mastocytes ont également un rôle paradoxal en contexte inflammatoire, en favorisant les processus de néo-angiogenèse, d’activation endothéliale et d’augmentation de la perméabilité vasculaire, phénomènes participant au recrutement de cellules inflammatoires sur le site lésionnel. L’axe IL-33/ST2 et les mastocytes, via leurs actions pro-Th2, immunorégulatrice, et pro-angiogénique, sont également associés aux processus de réparation tissulaire, qui pourraient s’avérer délétères en cas d’inflammation persistante, en raison du développement de lésions de fibrose. Si l’IL-33 ne semble pas être directement responsable d’une activation ou d’une prolifération fibroblastique au niveau artériel, les mastocytes activés par du sérum de patients ayant une vascularite des gros vaisseaux conduisent en revanche à des modifications du phénotype fibroblastique et induisent une augmentation de production de collagène de type 1 et de fibronectine.Dans la 2ème partie de nos travaux, nous avons mis en évidence des profils de différenciation distincts des lymphocytes T CD4+ dans la maladie de Takayasu et l’artérite à cellules géantes. Nous avons démontré une augmentation des lymphocytes T folliculaires helper (Tfh) circulants dans la maladie de Takayasu. L’augmentation des Tfhc chez les patients ayant une maladie de Takayasu est associée à une augmentation des lymphocytes B circulants et à la présence d’organes lymphoïdes ectopiques aortiques. Les Tfhc des patients Takayasu gardent les propriétés fonctionnelles des lymphocytes Tfh tissulaires, puisqu’ils favorisent la prolifération des lymphocytes B ainsi que leur différenciation en cellules mémoires. Nos résultats suggèrent donc l’implication d’une coopération lymphocytaire B et T centrale dans la physiopathologie de la maladie de Takayasu, qui pourrait être associée à la présence de lymphocytes B auto-réactifs sécrétant des auto-anticorps. / Large vessel vasculitis (LVV) mainly include Takayasu arteritis (TA) and giant cell arteritis (GCA), which are characterized by arterial inflammatory lesions, associated with adventitial neo-angiogenesis and fibrotic lesions. They predominantly involve aorta and its major branches. These diseases are related to unbalanced Th1 and Th17 immune responses. The mechanisms regulating lymphocyte differentiation, endothelial response and tissue homeostasis in arterial inflammatory diseases are not sufficiently known. First, we have studied the role of IL-33, which is a cytokine secreted by endothelial cells in response to tissue necrosis and is involved in the regulation of immune response. We demonstrated the immunomodulatory impact of IL-33 and mast cells in LVV. IL-33 had a direct immunomodulatory impact by increasing Th2 and regulatory T cells in PBMC. IL-33 and MC further enhanced Th2 and regulatory responses by inducing a 6.1 fold increased proportion of Tregs through increased indoleamine 2 3-dioxygenase (IDO) and IL-2 secretion. IL-33 and mast cells also had a paradoxical impact in LVV, by promoting angiogenesis, endothelial activation and vascular permeability. IL-33 and mast cells, through Th2 and regulatory responses and angiogenesis, were associated with tissue repair and arterial fibrosis. Although IL-33 did not appear to directly lead to arterial fibroblast activation and proliferation, mast cells activated by LVV serum induced increased production of type 1 collagen and fibronectin by arterial fibroblasts. In the second part of our work, we have demonstrated distinct differentiation profiles of CD4 + T cells in TA and GCA. We demonstrated an increase in circulating T follicular helper lymphocytes (cTfh), defined as CXCR5+ CD4+ T cells, in TA. The increase of cTfh was associated with an increase in circulating B lymphocytes and the presence of tertiary lymphoid organs in TA aorta. CXCR5+ CD4+ T cells of TA patients helped B cells to differentiate into memory cells, to proliferate and to secrete type G immunoglobulins. Our data provide evidence of the key coordinated role of Tfh and B cells in tertiary lymphoid structures in TA and suggest an antigenic trigger.
88

Análise molecular da proteína HC-Pro (Helper Component-Proteinase) e seu papel na relação patógeno-hospedeiro

Frangioni, Desiré Spada dos Santos [UNESP] 29 November 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:34:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-29Bitstream added on 2014-06-13T19:24:02Z : No. of bitstreams: 1 frangioni_dss_dr_botfca.pdf: 2302780 bytes, checksum: a3bab8cdfaa8a760d70900c13de09d8d (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O gênero Potyvirus é um dos maiores dentre os vírus de planta com genoma composto por RNA. O genoma dos potyvirus codifica um único polipeptídeo que é processado por três proteinases virais que originam todas as proteínas necessárias para complementar o ciclo da infecção. A proteína HC-Pro (Helper Component proteinase) é uma dessas proteínas multifuncionais que está envolvida na amplificação do genoma, transmissão por afídeo, movimento sistêmico e local, supressão do silenciamento gênico e proteólise. Nesse trabalho, foi realizada a substituição funcional de parte da região codificadora da HC-Pro do Lettuce mosaic virus (LMV) com a porção correspondente à HC-Pro do Potato virus Y (PVY), com o objetivo de melhor compreender os papéis dessa proteína no ciclo de infecção dos potyvirus. O LMV e o PVY diferem tanto em patogenicidade quanto em círculo de hospedeiros. O LMV infecta, principalmente, espécies da família Asteraceae (alface) enquanto o PVY infecta Solanaceae. Para avaliar o efeito de tal substituição na infectividade, dois vírus quiméricos foram construídos: um clone infeccioso de LMV contendo a HC-Pro selvagem do PVY (estendendo-se dos aminoácidos 1 a 352) e um segundo clone contendo a HC-Pro de PVY com mutação no motivo conservado IGN (mutado para RPN). Os vírus recombinantes e o LMV selvagem foram inoculados via biobalística em folhas de plântulas de alface cv. Trocadero (suscetível ao LMV). A presença e a natureza das progênies virais... / The genus Potyvirus is one of the largest genera of plant RNA viruses. The potyvirus genome encodes a single polypeptide that is processed by three viral proteinases to yield all viral proteins needed for the infection cycle. One of these proteins is the multifunctional helper component proteinase (HC-Pro), which is involved in genome amplification, aphid transmission, local and systemic movement, suppression of gene silencing and proteolysis. To gain further understanding of the roles of this protein in the Potyvirus life cycle, the functional replacement of the HC-Pro coding region of Lettuce mosaic virus (LMV) with its corresponding counterpart of Potato virus Y (PVY) was performed. These viruses differ both in pathogenicity and in host range. LMV infects mainly Asteraceae while PVY infects Solanaceae. To assess the functional requirement of a homologous HC-Pro in infectivity, two different chimeric viruses were constructed i. e: a full-length LMV containing a wild type PVY HC-Pro (1aa to 352aa) and a full-length LMV containing a PVY HC-Pro with a mutation in the IGN motif (exchanged to RNP). The chimeras, and wild type LMV, were inoculated by biolistic in young lettuce plants. The presence and nature of viral progenies were checked by RT-PCR amplification followed by sequencing. All recombinant viruses were infectious and displayed systemic infection although the symptoms were weak when compared to the wild type LMV. The viruses accumulation were evaluated by differential cycles in the RT-PCR. The LMV wild type was amplified by 30 cycles while the chimerics viruses needed 40 cycles. Therefore this result indicating that the chimeric viruses titer were lower than LMV wild type. The results 4 described here demonstrated that the main biological functions of HC-Pro can be accomplished by heterologous protein.
89

Papel de RAGE e TLR4 na modulação da resposta imune inflamatoria em PBMC de pacientes diabéticos e não diabéticos: (estudo in vitro)

Frasnelli, Sabrina Cruz Tfaile [UNESP] 26 March 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-03-26Bitstream added on 2014-06-13T19:15:56Z : No. of bitstreams: 1 frasnelli_sct_me_arafo.pdf: 758242 bytes, checksum: fc10d5e79dcb4b386aacc5d2776f572c (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Diabetes mellitus se caracteriza pelo acúmulo de produtos finais da glicação avançada (AGEs) que ativam seu receptor RAGE. Entre as complicações associadas ao diabetes está a modulação da resposta imune, evidenciada pela maior susceptibilidade à infecção em diabéticos. O sistema imune percebe e reaje aos microrganismos por meio de receptores de padrões moleculares (receptores semelhantes à Toll, TLRs). Lipopolissacarídeo da parede celular (LPS) é um dos principais fatores de virulência de microrganismos Gramnegativos e é reconhecido principalmente por TLR4. A hipótese deste trabalho é que a ativação de RAGE e TLR4 por seus ligantes pode resultar em efeito sinérgico na modulação da proliferação, morte celular e expressão de citocinas inflamatórias por células mononucleares do sangue periférico (PBMC). Foram selecionados 7 indivíduos não diabéticos e 6 indivíduos portadores de diabetes tipo 2 para coleta de PBMCs. Estas células foram estimuladas com LPS bacteriano e BSA glicado, isoladamente e combinados, na presença e na ausência de inibidores dos receptores RAGE e TLR4. Proliferação e morte celular foram avaliadas por contagem direta em hemocitômetro e citometria de fluxo, respectivamente. A expressão de citocinas e quimiocinas inflamatórias foi avaliada por RT-qPCR, enquanto a modulação do padrão de resposta imune adaptativa foi estudada por meio de citometria de fluxo. Os resultados mostram 18 18 que PBMCs de pacientes portadores de diabetes tendem a ser mais resistentes à indução de morte celular. De um modo geral, a inibição dos receptores RAGE e TLR4 não interfere na atividade metabólica e viabilidade celular em diabéticos e não diabéticos. A expressão gênica de CCL3 e CCR5 não foi regulada pelos receptores RAGE e TLR, sendo discretamente mais elevada em pacientes não diabéticos. A expressão de TNF-α e IL-10 foi regulada... / Diabetes mellitus is characterized by the progressive accumulation of advanced glycation end-products (AGEs), which bind and activate their membrane-bound receptor (RAGE) on a variety of target cells. Modulation of the immune response is one of the diabetes-associated complications and is reflected on the increased susceptibility of diabetes patients to infections and sepsis. The immune system senses and reacts to microorganisms by pattern-recognition receptors, such as Toll-like receptors (TLRs). Bacterial lipopolysaccharide (LPS) is a major virulence factor of Gram-negative microorganisms, which is recognized mainly by TLR4. The hypothesis of this study is that of a synergism between activated TLR4 and RAGE that modulates the response of cells of innate and adaptive immunity in the circulation (peripheral blood monocytic cells, PBMCs). PBMCs were collected from 13 volunteers (7 with type 2 diabetes and 6 systemically-healthy controls). The cells were stimulated with bacterial LPS and glycated bovine serum albumin (AGE-BSA), both independently and in association. To study the role of TLR4 and RAGE signaling, these stimulations were performed in the presence and absence of specific inhibitors of RAGE and TLR4. We used direct counting in a hemocytometer and flow cytometry, respectively, to assess cell proliferation and 20 20 death. The expression of selected cytokines and receptors was studied by RTqPCR, whereas the effect of these stimuli on the modulation of T helper-type response was determined by flow cytometry. We observed increased cell survival in PBMCs from diabetic patients. Inhibition of RAGE and TLR4 had no marked effect on cell proliferation, metabolic activity and survival. Gene expression of CCL3 (MIP-1alpha) and CCR5 was discretely higher in PBMCs from non-diabetic patients and was not affected by RAGE or TLR4 signaling... (Complete abstract click electronic access below)
90

Papel de RAGE e TLR4 na modulação da resposta imune inflamatoria em PBMC de pacientes diabéticos e não diabéticos : (estudo in vitro) /

Frasnelli, Sabrina Cruz Tfaile. January 2012 (has links)
Orientador: Carlos Rossa Junior / Coorientador: Silvana Regina Perez Orrico / Banca: José Eduardo Cezar Sampaio / Banca: Sandra Helena Penha de Oliveira / Resumo: Diabetes mellitus se caracteriza pelo acúmulo de produtos finais da glicação avançada (AGEs) que ativam seu receptor RAGE. Entre as complicações associadas ao diabetes está a modulação da resposta imune, evidenciada pela maior susceptibilidade à infecção em diabéticos. O sistema imune percebe e reaje aos microrganismos por meio de receptores de padrões moleculares (receptores semelhantes à Toll, TLRs). Lipopolissacarídeo da parede celular (LPS) é um dos principais fatores de virulência de microrganismos Gramnegativos e é reconhecido principalmente por TLR4. A hipótese deste trabalho é que a ativação de RAGE e TLR4 por seus ligantes pode resultar em efeito sinérgico na modulação da proliferação, morte celular e expressão de citocinas inflamatórias por células mononucleares do sangue periférico (PBMC). Foram selecionados 7 indivíduos não diabéticos e 6 indivíduos portadores de diabetes tipo 2 para coleta de PBMCs. Estas células foram estimuladas com LPS bacteriano e BSA glicado, isoladamente e combinados, na presença e na ausência de inibidores dos receptores RAGE e TLR4. Proliferação e morte celular foram avaliadas por contagem direta em hemocitômetro e citometria de fluxo, respectivamente. A expressão de citocinas e quimiocinas inflamatórias foi avaliada por RT-qPCR, enquanto a modulação do padrão de resposta imune adaptativa foi estudada por meio de citometria de fluxo. Os resultados mostram 18 18 que PBMCs de pacientes portadores de diabetes tendem a ser mais resistentes à indução de morte celular. De um modo geral, a inibição dos receptores RAGE e TLR4 não interfere na atividade metabólica e viabilidade celular em diabéticos e não diabéticos. A expressão gênica de CCL3 e CCR5 não foi regulada pelos receptores RAGE e TLR, sendo discretamente mais elevada em pacientes não diabéticos. A expressão de TNF-α e IL-10 foi regulada... (Resumo completo, clicar acesso eletr^ônico abaixo) / Abstract: Diabetes mellitus is characterized by the progressive accumulation of advanced glycation end-products (AGEs), which bind and activate their membrane-bound receptor (RAGE) on a variety of target cells. Modulation of the immune response is one of the diabetes-associated complications and is reflected on the increased susceptibility of diabetes patients to infections and sepsis. The immune system senses and reacts to microorganisms by pattern-recognition receptors, such as Toll-like receptors (TLRs). Bacterial lipopolysaccharide (LPS) is a major virulence factor of Gram-negative microorganisms, which is recognized mainly by TLR4. The hypothesis of this study is that of a synergism between activated TLR4 and RAGE that modulates the response of cells of innate and adaptive immunity in the circulation (peripheral blood monocytic cells, PBMCs). PBMCs were collected from 13 volunteers (7 with type 2 diabetes and 6 systemically-healthy controls). The cells were stimulated with bacterial LPS and glycated bovine serum albumin (AGE-BSA), both independently and in association. To study the role of TLR4 and RAGE signaling, these stimulations were performed in the presence and absence of specific inhibitors of RAGE and TLR4. We used direct counting in a hemocytometer and flow cytometry, respectively, to assess cell proliferation and 20 20 death. The expression of selected cytokines and receptors was studied by RTqPCR, whereas the effect of these stimuli on the modulation of T helper-type response was determined by flow cytometry. We observed increased cell survival in PBMCs from diabetic patients. Inhibition of RAGE and TLR4 had no marked effect on cell proliferation, metabolic activity and survival. Gene expression of CCL3 (MIP-1alpha) and CCR5 was discretely higher in PBMCs from non-diabetic patients and was not affected by RAGE or TLR4 signaling... (Complete abstract click electronic access below) / Mestre

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