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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

Particular experiences : a psychosocial exploration of myalgic encephalomyelitis (ME) and its relationship with self, environment and the material world

Fellenor, John January 2015 (has links)
Myalgic encephalomyelitis (ME), also referred to as chronic fatigue syndrome (CFS), is a symptomatically defined and debilitating condition that presents as a range of physiological and psychological effects. Post-exertional fatigue and ongoing low energy levels are cardinal features. Whilst ME-like conditions have been recognised for at least two hundred years, they have been characterised over recent decades by a fiercely contested debate as to whether aetiology is primarily psychological or physiological. ME sufferers experience profound changes to their self-perception, ability to maintain daily routines and activities and how they are perceived in terms of their capacity to carry out social roles, including illness-status. The contested aetiology results in-part from a climate of dualistic thought and the biomedical model upon which ME is treated and theorised. Whilst the effects of ME on self experience have been investigated from various qualitative and quantitative perspectives, the primary purpose of this thesis is to develop a psychosocial framework from which to explore previously neglected dimensions of the effect of ME on self experience. Developing a psychosocial understanding of ME is in keeping with a turn towards post-Cartesian and non-dualistic thinking. The second interconnected purpose of this thesis is to address the role played by the material environment and objects and to conceptualise their importance and relation to self and how it is affected by ME. This is currently absent in the literature on ME. Developing a psychosocial framework suitable for this purpose rested on a synthesis of Actor Network Theory (ANT) and a psychoanalytically influenced use of metaphor and metonymy. At the heart of this synthesis are the notions of relational ontology (Latour, 1997; DeLanda, 2002) and assemblage (Deleuze and Guattari, 1987; DeLanda, 2002; Hodder, 2012). A relational ontology focuses on the relations between disparate objects such as material artefacts, humans, other organisms and concepts and avoids prioritising any one ‘thing’ as more important than another. The notion of assemblage has emerged alongside ideas concerning complexity, chaos and indeterminacy and informs a vocabulary addressing the problem of causality, determination and the stability of social and psychological phenomena (Venn, 2006). As part of a psychoanalytically informed psychosocial framework these concepts enable an exploration of ME by bringing together disparate aspects such as everyday objects, experiences, symptoms and environments in a non-causal, non-dualistic and processual manner. The psychoanalytic element also enables an exploration of the unconscious and irrational aspects of experience, which is most pertinent with regards to the effects of ME. Thus, the premise of this research was to establish a psychosocial methodology and theoretical basis from which to explore the effects of ME on self experience. Moreover, this methodology was designed to engage with the complex, coincident and entangled nature of the symptoms, discourses, objects, material artefacts, environments and non-human organisms that ME appears to be comprised of. Methods were developed which enabled the researcher to be with and explore the day-to-day life and routines of eight ME sufferers in their everyday environments over a six month period. This involved working with the ME sufferers taking part primarily in their own homes and spaces around their home which they frequented, such as shopping malls and even a cemetery; in itself novel in terms of qualitative research into ME. Of these eight sufferers, three were male [age range 49 – 65; earliest formal diagnosis of ME occurring in 2005] and five females [age range 25 – 63; earliest diagnosis 2002]. Two sufferers were in paid employment, one was retired and five were unable to work due to their ME. Due to the extensive nature of the data, only 3 case studies, two male and three female, were selected for in-depth analysis. Cases selected were those that most clearly illustrated central analytic themes. Data comprised talk, audio-visual material and the affective responses of the researcher. Analytic methods were devised which initially adopted a thematic approach before metaphoric and metonymic equivalences were drawn between what ME sufferers discussed and aspects of the routines, objects and environments they were engaged with. This informed descriptions of how these things became networked, in an ANT sense, and how self experience was implicated. A key finding which emerged is the notion of debilitating spaces. This term captures the manner in which, for certain sufferers, the experience and hence the maintenance of ME was intrinsically enmeshed with their immediate physical environment. Further findings discussed include the way in which seemingly everyday objects such as food blenders can be co-opted by sufferers as a means of enhancing their self-experience in light of ME. Overall, the findings of this PhD are discussed in terms of the success and applicability of that premise and its contribution to the field of psychosocial approaches. The key assertion is that the methodology enhances an understanding of ME and its effects, highlighting the variable yet particular nature of ME and its effect on self experience and in incorporating the hitherto unconsidered range of objects outlined above.
82

Characterisation of fatty acid amide hydrolase as a potential therapeutic target in Multiple Sclerosis

Graves, Ryan Stanley January 2013 (has links)
Multiple sclerosis (MS) is a demyelinating neurodegenerative disease that typically has a relapsing-remitting pattern of progression superimposed on a gradual worsening of disease symptoms. Experimental autoimmune encephalomyelitis (EAE) is a model of MS where animals develop relapses, demyelination and accumulate neurological deficits. Studies using the EAE model have provided evidence that cannabinoids are beneficial in reducing disease symptoms and may impact long term neurodegeneration, but side-effects of exogenous cannabinoid receptor agonists may limit their potential as therapeutic agents for MS. Targeting enzymes involved in degradation of endocannabinoids such as the anandamide-degrading enzyme fatty acid amide hydrolase (FAAH) may be an attractive alternative strategy. Using experimental allergic encephalomyelitis (EAE) as a mouse model of MS, two complementary approaches were used to assess FAAH as a potential therapeutic target. The FAAH deficient (ABH.FAAH-/-) developed similar paralytic relapsing disease of similar severity of disease compared to the wild-type, but showed a poorer recovery following the acute phase. However, following a relapsing-remitting disease course, the FAAH deficient mice showed a substantial improvement in clinical score, improved motor control, and lost less neurofilament compared to wild-type mice. These findings indicate that fatty acid amides may be neuroprotective in EAE. Secondly, a selective FAAH inhibitor (PF-3845; 10 mg/kg) was used to treat mice during the relapse phase of the disease course. Treatment with PF-3845 caused an elevation of anandamide in the CNS. This treatment resulted in a small reduction in neurofilament loss, but no reduction in clinical score or improvement in motor control was observed compared to the vehicle treated group. To investigate at a cellular level how FAAH might affect disease progression in the EAE model, immunohistochemistry was used to analyse FAAH expression in the CNS. Employing novel antibodies to FAAH in combination with neuronal and glial cell markers, it was found that, in addition to previously reported neuronal expression of FAAH, FAAH is highly expressed 3 in oligodendrocytes, but not in other glial cell types. Thus, genetic deletion or pharmacological inhibition of FAAH may affect both neuronal activity and oligodendroglial function (e.g. myelination). The role of FAAH in oligodendrocytes was investigated in vitro. An oligodendrocyte precursor cell (OPC) monoculture was used to monitor differentiation, and a co-culture comprising neurons and OPCs was used to monitor myelination. During the differentiation of OPCs, FAAH expression was detected in the entire oligodendroglia lineage, but with high expression only in mature myelin basic protein (MBP) expressing cells. Treatment with the FAAH inhibitor PF-3845 (0.1 μM to 1 μM) increased differentiation of OPCs into mature oligodendrocytes. However, the same treatment of co-cultures had no effect on the myelination of neurites. In conclusion, this study has: i) obtained evidence that genetic deletion of FAAH is neuroprotective in a mouse model of MS and ii) provided new insights on FAAH expression in the CNS. Further investigation of FAAH, in particular its role(s) in oligodendrocytes, will be required to fully unlock the therapeutic potential of FAAH inhibition in the treatment of MS.
83

Investigating the role of T-bet in CD4+ T cell driven central nervous system autoimmunity

Cambrook, Helen Elizabeth January 2014 (has links)
Self-reactive CD4+ helper T cells (Th) are key causal agents in the pathogenesis of many autoimmune diseases. Experimental autoimmune encephalomyelitis (EAE) is a CD4+T cell model of the demyelinating autoimmune disease multiple sclerosis (MS). It has been shown that EAE is caused by CD4+ T-cells that produce pro-inflammatory cytokines IFN-γ (Th1) and IL-17 (Th17). As such, understanding how these Th cells are generated and controlled is essential. There is debate as to whether Th1 and Th17 cells act independently in EAE or if there is plasticity between these two subtypes, and whether the capacity to switch from Th1 to Th17 confers pathogenic capacity. T-bet was first described as the master transcription factor for Th1 cells, and is thought to have a critical role in EAE even though IFN-γ, the Th1 archetypal cytokine, has been shown to be redundant. More recent work has shown that T-bet is expressed in multiple immune cell types, and it remains unclear in what cells the expression of T-bet is required for EAE. Considerable efforts have been put into understanding the role of T-bet in EAE pathogenesis, with a view to modulate cells expressing T-bet for therapy. The hypothesis of this work was that T-bet has multifaceted roles in EAE, in initiating and directing an immune response in innate antigen presenting cells such as dendritic cells (DC) as well as programming pathogenic effector CD4+ T cell (Teff) response to antigen. T-bet-/- mice were studied using different models of EAE to dissect the role of T-bet in disease pathogenesis. Active immunisation of C57BL/6 mice with the immunodominant peptide from myelin oligodendrocyte glycoprotein (MOG35-55) showed that T-bet-/- mice developed EAE with an IL-17 dominated profile and critically, T-bet-/- mice were able to produce GM-CSF which has recently been described as a key cytokine for EAE. T-bet-/- cells were not able to transfer EAE in a model of passive transfer EAE, where CD4+ T cells were polarised towards a Th1 profile in vitro. Illustrating that T-bet is required in CD4+ T cells for Th1 mediated EAE. DC driven EAE showed that T-bet-/- DC were able to activate CD4+ T cells in vitro and cause EAE upon co-transfer into host mice with transgenic CD4+ T cells. Thus, it has been shown that T-bet is not required in EAE. This work represents a step further towards understanding the disease mechanisms involved in EAE and suggests T-bet is not an appropriate therapeutic target for the treatment of MS.
84

Investigating mechanisms of regulatory T cell function in inflammatory disease

Mair, Iris January 2017 (has links)
Regulatory T cells (Treg) play a crucial role in controlling immune homeostasis. Several inflammatory diseases including multiple sclerosis and inflammatory bowel disease have been associated with dysfunctional and/or reduced numbers of Treg. While several mechanisms of action have been discovered by which Treg can exert their function, disease-specific Treg requirements remain unknown. The Treg pool consists of highly diverse subpopulations, indicating that there is a potential to optimise Treg-targeted therapies if disease-relevant mechanisms can be established. Microarray data from our lab suggests a marked upregulation of the integrin αv as well as the IL-33 receptor ST2 in Treg retrieved from the inflamed central nervous system (CNS) during experimental autoimmune encephalomyelitis compared to peripheral lymphoid organs. These two molecules were further investigated within this PhD project with the aim to understand their role in Treg function during chronic inflammatory disease. αvβ integrins have been reported to be needed for effector T cell migration to inflamed sites through binding of extracellular matrix components and are involved in TGF-β activation by a variety of cell types. Conditional knockout mice lacking the integrin αv specifically in Foxpγ+ Treg were generated to address the role of αv integrins on regulatory T cells in inflammatory disease. αv-/- Treg showed a deficiency in activating latent TGF-β, but were able to suppress responder T cell proliferation in vitro as well as in vivo. αv-/- Treg were also able to migrate to the inflamed CNS during EAE and resolve disease. However, αv-/- Treg were detected at significantly lower numbers and proportions in the inflamed gut during a curative T cell transfer model of colitis; this led to a quantitative impairment in the ability of αv-/- Treg to cure colitis when compared to wild-type (WT) Treg. Whether this is a deficit in migration, survival, proliferation, or Foxp3 stability, remains to be investigated. IL-33 acts as an alarmin and is best studied as a cytokine released upon tissue damage that induces a potent type 2 immune response by acting on a multitude of immune cells. Expression of the IL-33 receptor ST2 on Treg has recently been associated with positive metabolic parameters in visceral adipose tissue, protection from gut inflammation, and tissue-restorative function in other inflamed tissues such as injured muscle or lung. This project showed that in steady state, ST2+ Treg expressed high levels of several markers which have been associated with potent regulatory function. When stimulated in vitro, ST2+ Treg showed a better survival and expansion rate compared to their ST2- counterparts, even more so in the presence of IL-33. T-bet deficiency in Treg resulted in an increased ST2+ Treg pool, and T-bet-associated cytokine IFN-γ was found to antagonise IL-33-induced expansion of the ST2+ Treg pool in a T-bet-independent manner. When ST2+ and ST2- Treg were tested for their respective suppressive capacity in vivo, ST2+ Treg were able to suppress responder T cell expansion despite being found only at low numbers in secondary lymphoid organs compared to ST2- Treg. However, in a curative model of T cell transfer colitis, ST2+ Treg were less capable of controlling the ongoing immune response than ST2- Treg. A possible explanation for the superiority of ST2- Treg in this setting can be found in the fact that injected ST2- Treg acquired a distribution of ST2 expression reminiscent of WT Treg over the course of disease. On the other hand, an increased starting pool of ST2+ Treg as occurs in T-bet-/- Treg significantly enhanced the capacity of Treg to control colitis compared to WT Treg. In conclusion, both ST2- and ST2+ Treg are likely to have a distinct, non-redundant role in suppressing T cell activation in secondary lymphoid organs and controlling ongoing inflammation in peripheral tissue, respectively.
85

In situ studies on Foxp3+ regulatory T cells in central nervous system autoimmune disease

Zandee, Stephanie Elizabeth Johanna January 2016 (has links)
In multiple sclerosis (MS), pathogenic T effector cells (Teff) are believed to orchestrate immune-mediated destruction of the central nervous system (CNS) myelin sheath. In experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, CNS infiltration by regulatory T cells (Treg), producing the anti-inflammatory cytokine IL-10, promotes the resolution of disease. Currently, little is understood about how Treg function within the inflamed CNS and on which cells they exert their suppressive function. There is a debate as to whether Treg in MS patients are capable of infiltrating the CNS and if they do, it is unclear whether they are functional. Understanding Treg function in EAE and MS could open up new possibilities for treatment, as Treg could be modulated for immunosuppressive therapy. A key step in the development of EAE (and presumably MS) is the ability of Teff cells to cross the blood brain barrier (BBB) and enter the CNS parenchyma. The hypothesis of this work was that Treg facilitate resolution of the inflamed CNS by preventing entry of the pathogenic T cells into the CNS parenchyma, thus preventing further damage. As such, it is important to understand with which immune cells and CNS resident cells Treg communicate to achieve resolution of disease. The presence of Treg in MS lesions was investigated with double immunohistochemistry (IHC) in frozen post-mortem MS brain tissue. CD4+Foxp3+ Treg were present in a subset of patients and their presence was associated with perivascular retention of CD4+Foxp3- and CD8+Foxp3- T cells. Foxp3+ cells in MS lesions predominantly expressed IL-10, indicating regulatory activity, although low-level production of IL-17, TNF-α, IFN-γ and GM-CSF was observed as well. Generally, analysis of total cytokine expression identified distinct patterns of cytokine production between lesions. Nonetheless, these could not be used to discriminate individual patients. These studies were repeated in C57BL/6 mice in which the Treg population was depleted before onset of EAE to mimic lesions with and without Treg presence, as found in MS patients. An immunofluorescent technique to study up to 5 fluorochromes simultaneously was developed to study antigen presenting cell (APC), Teff and Treg location, spatial relationship and function (as measured by cytokine expression) in the CNS of EAE mice at different stages of disease. Using this technique it was found that CD4+Foxp3- Teff and CD4+Foxp3+ Treg were located within 50-100μm of CD11c+ APC in the CNS of EAE affected mice. CNS Teff and Treg predominantly produced IFN-γ or IL-10, although low levels of IL-17 were detected in Teff and Treg as well. IL-17+ Treg were close to IL-17+ Teff, IFN-γ+ Treg were close to IFN-γ+ Teff, but IL-10+ Treg were not in close proximity to IL-10+ T cells in the CNS during EAE. In conclusion, there is evidence for functional Treg in EAE and MS lesions, supporting the concept of enhancing Treg activity as a clinical intervention. Treg seem to be capable of retaining pathogenic T cells at the blood brain barrier in MS lesions. In addition, studies of cytokine expression in MS lesions indicated that there is no sound basis for patient stratification based on peripheral blood cytokine profile. This thesis advances our understanding of Treg location, function and spatial relationship with other immune cells within the inflamed CNS.
86

CD4+ T cell responses to myelin autoantigens : activation, memory and tolerance

Chung, Chen-Yen January 2009 (has links)
Experimental autoimmune encephalomyelitis (EAE) is a CD4+ T cell mediated autoimmune disease of the central nervous system and shares many characteristics with multiple sclerosis (MS). Induction of EAE is mediated by myelin reactive CD4+ T helper (Th) cells, particularly Th1 and Th17 cells, which can be provoked by the immunization with myelin derived protein (or peptide) and Toll-like receptor (TLR) stimulus (eg, complete Freund¡s adjuvant, CFA). If given an injection of soluble peptide before immunization, mice do not develop EAE (they are tolerant). This approach has been widely applied, evoking tolerance in primary responses (i.e., in naive T cells). Therefore the first hypothesis of this thesis is that peptide induced protection from EAE is a result from T cell deletion or / and anergy. As MS patients have ongoing disease and over 85% of MS patients develop a relapsing-remitting course, memory T cells are key targets when considering peptide-induced tolerance as a therapeutic strategy. Thus, a model for ¡memory EAE¡ was established to test a second hypothesis that the myelin reactive memory T cells can be controlled by the administration of soluble peptide. Here, adoptive transfer of T cells from T cell receptor transgenic mice (2D2) recognizing myelin oligodendrocyte glycoprotein 35-55 (pMOG) was used to investigate the pMOG-reactive memory responses. Soluble pMOG administration could induce a transient expansion of 2D2 T cells followed by their loss through apoptosis. A model using double immunization was established by immunizing mice first with pMOG together with unmethylated CpG oligonucleotide (CpG) as an adjuvant, and subsequently immunizing with pMOG in CFA. This produced EAE with early onset and high incidence compared to mice which received pMOG/CFA only. Cells from mice that received the double immunization protocol produced high levels of IFN-γ, suggesting that memory T cell responses have been triggered in the mice. Administration of soluble peptide before secondary immunization could ameliorate EAE, indicating that memory T cells are susceptible to tolerance induction. pMOG-reactive memory T cells were further assessed by isolating CD4+ CD25- CD44high CD62Llow cells from pMOG-experienced 2D2 mice. These cells showed early and high production of IFN-γ, and early but transient production of IL-2, compared with naive population. These data provide basic information relevant to translating peptide-induced T cell tolerance from mice to humans.
87

Regulatory T cells : molecular requirements for their selection and therapeutic use in autoimmune disease

Malpass, Katy H. January 2009 (has links)
Regulatory T cells (Tregs), expressing the transcription factor Foxp3, form a key component of peripheral immune tolerance, guarding against auto-aggressive immune responses. Multiple Sclerosis is an inflammatory and demyelinating disease of the central nervous system (CNS) which is largely believed to be mediated by immune components reacting to the self myelin antigens that insulate the nerve fibres. Recent investigations have reported that regulatory T cells are dysfunctional in MS patients; therefore enhancing the regulatory T cell responses in MS is an attractive therapeutic target. Using the mouse model of MS, experimental autoimmune encephalomyelitis (EAE) we have attempted to develop disease-relevant Treg-based therapies to prevent disease induction. This required an understanding of the antigenic-reactivity of Tregs during disease. Results described in this thesis show that a proportion of Tregs in the draining lymph nodes and CNS were reactive to the disease initiating antigen(s) and could suppress in vitro responses of naïve T cells bearing transgenic T cell receptors, recognising the same antigen. Adoptive transfer of antigen-reactive Tregs suppressed disease induced with the same antigen, but also reduced disease induced with a distinct myelin antigen. Peptide-based tolerance using a high affinity MHC binding peptide analogue expanded and maintained antigen-reactive T cells which were tolerant to antigenic restimulation, although these cells did not express Foxp3. Peptide-treated mice showed reduced incidence of disease relapses during EAE induced against a distinct myelin antigen. Thus, while EAE and MS will involve a polyclonal effector T cell response to many antigens, therapeutic targeting of Tregs reactive against one CNS component may be sufficient to reduce disease. Endogenous expression of myelin autoantigen did not grossly alter the response of antigenreactive Tregs in the periphery. However, expression of endogenously derived viral superantigen enhanced the proportion of superantigen-reactive Foxp3+ Tregs in the periphery. This observation was extended using exogenous superantigen, suggesting that prolonged exposure to low dose (super)antigen tips the balance of the immune system in favour of regulation. This has implications for the ability to successfully fight infection, as well as for the limitation of autoaggressive responses and may contribute to the understanding of the hygiene hypothesis.
88

Infecção por paramixovírus tipo 1 em pombos (Columba livia) no sul do Brasil

Souza, Suyene Oltramari de January 2016 (has links)
A doença de Newcastle, causada por cepas patogênicas de paramixovírus aviário 1 (APMV-1), é uma doença de aves importante por causar altos índices de mortalidade e perdas econômicas. Em aves da ordem Columbiformes, vários surtos têm sido relatados ao longo de 30 anos, em diferentes partes do mundo, causados por uma cepa denominada pigeon paramyxovirus tipo 1 (PPMV-1). Este trabalho descreve um surto de mortalidade em pombos domésticos (Columba livia), provenientes de uma praça pública, no município de Porto Alegre, no Sul do Brasil, ocorrido no mês de novembro de 2014. Aves moribundas e mortas, no intervalo de cinco semanas, foram submetidas ao exame de necropsia, exame histopatológico, imuno-histoquímico anti- Newcastle, de transcrição reversa seguida da reação em cadeia da polimerase (RTPCR), exame de sequenciamento e analise filogenética. Foram acometidas aves adultas, de ambos os sexos e a mortalidade foi estimada em 80%, os sinais neurológicos apresentados foram tremores da cabeça, torcicolo, dificuldade em manter-se em estação, dificuldade de locomoção, paresia, paralisia, asas caídas e vômito. As lesões encontradas no exame macroscópico eram inespecíficas e no exame histológico do sistema nervoso central eram caracterizadas por encefalite e encefalomielite não supurativas. No rim, fígado e pâncreas foi observado infiltrado inflamatório mononuclear, que por vezes era associado à necrose. No baço, além de necrose, foi observado depleção linfoide e infiltrado de macrófagos. Das 24 aves testadas para a RTPCR, seis foram positivas para a proteína da matriz (M) e através do sequenciamento destas amostras, pode-se identificar que todas as aves foram acometidas pela mesma cepa viral. Para confirmação de que a cepa encontrada tratava-se de uma cepa virulenta, foi feita a análise por sequenciamento do sítio de clivagem da proteína F, comparando a sequência de aminoácidos encontrada, 112RRQKRF117, com outras cepas já conhecidas. Observou-se que as amostras analisadas apresentaram aminoácidos na região do sítio de clivagem da proteína F, compatíveis com cepas virulentas. De acordo com a análise filogenética, o virus foi classificado como pertencente à classe II e ao genótipo VI. Ao exame imuno-histoquimico, a marcação foi observada no cérebro, no citoplasma de astrócitos e no núcleo de neurônios; no fígado, associada ao infiltrado inflamatório no interior de macrófagos; em células epiteliais do pâncreas exócrino e no citoplasma de células epiteliais do rim. / The Newcastle disease caused by avian paramyxovirus 1 strains (APMV-1) is an important avian disease involved into high rates of mortality and economic losses. Over the last 30 years several outbreaks have been reported in the order Columbiformes in many parts of the world caused by a strain, known as pigeon paramyxovirus type 1 (PPMV-1). This paper describes a mortality outbreak in free-living pigeons (Columba livia) from a public square in a city in Southern Brazil, occurred in November 2014. Moribund or freshly dead pigeons, within five weeks interval, were submitted to necropsy, histopathological, immunohistochemical (anti-Newcastle), Reverse transcription polymerase chain reaction (RT-PCR), sequencing analisys and phylogenetic analysis. It was affected only adult free-living pigeons of both sexes, and the mortality was estimated at 80%. Neurological signs presented by the pigeons were head tremors, stiff neck, lack of balance, incoordination, paresis, paralysis, drooped wings, and vomit. Gross findings were nonspecific. Histological findings in the central nervous system were characterized by encephalitis and encephalomyelitis nonsuppurative. In the kidney, liver and pancreas was observed mononuclear inflammatory infiltrate, which sometimes was associated with necrosis. In the spleen was observed necrosis, lymphoid depletion and macrophage infiltration. Out of 24 pigeons examined by RT-PCR, 6 pigeons had positive signal for the presence of matrix (M) protein gene and by sequencing analysis it appears that the sequences were identical to each other. The complete genome sequence and the complete coding sequence of the fusion (F) gene according to the unified NDV classification system showed that isolate had cleavage site 112RRQKRF117 which is characteristic of velogenic strains. Phylogenetic analysis showed that this strain could be classified into class II and genotype VI. Immunohistochemical analysis showed that the virus antigens were detected in astrocytes and in neurons in the brain, in liver macrophages, in exocrine pancreas epithelial cells, and in kidney epithelial cells.
89

Avaliação da capacidade reguladora de células tronco mesenquimais endometriais no modelo de encefalomielite experimental automimune. / Evaluation of the regulatory capacity of endometrial mesenchymal stem cells in the experimental autoimmune encephalomyelitis model.

Polonio, Carolina Manganeli 13 July 2017 (has links)
A esclerose múltipla é uma doença inflamatória crônica desencadeada por células T autorreativas contra antígenos proteicos da mielina. A encefalomielite experimental autoimune é o modelo murino mais utilizado para o estudo da EM. As tubas uterinas e o útero de camundongos fêmeas são órgãos ricos em células mesenquimais que são pouco utilizadas em estudos. Dessa forma, no presente projeto, caracterizamos a obtenção dessa população e avaliamos sua capacidade imunossupressora utilizando o modelo de EAE. Observamos que o tratamento é capaz de modular o perfil de linfócitos T CD4+ durante sua ativação nos linfonodos, induzindo o direcionamento para a subpopulação Tr1 e atenuando as Th1 e Th17. Assim, houve uma diminuição do número de células infiltrantes no SNC associado a uma menor ativação de células da microglia. Em conjunto, demostraramos que as meMSC utilizadas como tratamento são capazes de atrasar o desenvolvimento da EAE e, portanto, evidenciando o caráter imunomodulador das MSCs derivadas do endométrio, chamando a atenção para seu potencial terapêutico. / Multiple sclerosis is a chronic inflammatory disease triggered by autoreactive T cells against myelin protein. Experimental Autoimmune Encephalomyelitis is the most commonly used murine model for the study of MS. The uterine tubes and uterus of female mice are organs rich in mesenchymal cells which are rarely used. Thus, in the present work, we characterized the extraction of this population and evaluated its immunosuppressive capacity using the EAE model. We observed that the meMSC treatment is capable of modulating the CD4 T lymphocyte profile during its activation in the lymph nodes, inducing the expansion of the Tr1 subpopulation and attenuating Th1 and Th17. Consequently, there was a decrease in the number of infiltrating cells in the CNS associated with a reduction of microglial activation. Taken together, our results demonstrated that the meMSCs used as treatment are capable of delaying the development of EAE, therefore, evidencing its immunomodulatory features drawing attention to its therapeutic potential.
90

MODULATION OF IMMUNE FUNCTION AND PROMOTION OF RESTORATIVE GENE EXPRESSION BY AF4 IN A MOUSE MODEL OF EXPERIMENTAL AUTOIMMUNE ENCEPHALOMYELITIS

Warford, Jordan R. 04 December 2012 (has links)
The anti-inflammatory and restorative effects of the flavonoid-enriched fraction AF4 were examined in a mouse model of experimental autoimmune encephalomyelitis (EAE). Relative to EAE mice that received vehicle (water, 10 ml/kg/day), oral administration of AF4 (25 mg/kg/day) beginning 24 hours after the onset of clinical signs reduced disease progression that was accompanied by diminished pro-inflammatory cytokine gene expression (cerebellum and spinal cord) and protein concentrations in the plasma. LPS-induced release of TNF-? from the whole blood of EAE mice that received AF4 was reduced at peak disease severity (day 18) but not once central inflammation had declined (day 31) indicative of unique immune modulator properties. Lastly, the expression of myelin-associated genes (PGC-1?, SCD1, and MBP) suggestive of remyelination was enhanced in the spinal cord of EAE mice that received AF4. These findings suggest that AF4 reduces EAE severity by selectively inhibiting autoimmunity and enhancing the expression of genes necessary for remyelination.

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