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1

King, Marie A. "The Humanized Mouse Model: The Study of the Human Alloimmune Response: A Dissertation." eScholarship@UMMS, 2008. https://escholarship.umassmed.edu/gsbs_diss/374.

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The transplantation of allogeneic cells and tissues for the treatment of human disease has been a life-saving procedure for many thousands of patients worldwide. However, to date, neither solid organ transplantation nor bone marrow transplantation have reached their full clinical potential. Significant limitations to the advancement of clinical transplantation stem from our current inability to prevent the rejection of allogeneic tissues by the immune system of the host. Similarly, in patients that receive allogeneic bone marrow transplants, we cannot permanently prevent the engrafted immune system from mounting a response against the patient. This problem, termed graft versus host disease is the most prevalent cause of morbidity and mortality in recipients of allogeneic bone marrow transplants. Clinically, we rely on lifelong immunosuppression to prolong survival of allogeneic tissues within the host. Our currently available therapeutics burden patients with side-effects that range from being unpleasant to life-threatening, while in most cases offering only a temporary solution to the problem of alloimmunity. Efforts are underway to develop protocols and therapeutics that more effectively prevent the pathology associated with alloimmunity. To minimize patient risk, extensive pre-clinical studies in laboratory animals are conducted to predict clinical responses. In the case of immunologic studies, many of these pre-clinical studies are carried out in murine models. Unfortunately, studies of murine immunity often do not predict outcomes in the clinic. One approach to overcome this limitation is the development of a small animal model of the human immune system. In this dissertation, we hypothesized that NOD-scid IL2rγnull mice engrafted with human peripheral blood mononuclear cells (PBMC), termed the hu-PBMC-NOD-scid IL2rγnull model, would provide a model that more accurately reflects human immunity in vivo than other models currently available. To investigate this possibility, we first investigated whether NOD-scid IL2rγnull mice were able to support the engraftment of human PBMC. We found that NOD-scid IL2rγnull mice engraft with human PBMC at much higher levels then the previous gold standard model, the NOD-scid mouse. We then investigated the kinetics of human cell engraftment, determined the optimal cell dose, and defined the influence of injection route on engraftment levels. Even at low PBMC input, NOD-scid IL2rγnullmice reproducibly support high levels of human PBMC engraftment. In contrast to previous stocks of immunodeficient mice, we observed low intra- and interdonor variability of engraftment. We next hypothesized that the human PBMC engrafted in NOD-scid IL2rγnull mice were functional and would reject transplanted allogeneic human tissues. To test this, human islets were transplanted into the spleen of chemically diabetic NOD-scid IL2rγnull mice with or without intravenous injection of HLA-mismatched human PBMC. In the absence of allogeneic PBMC, the human islets were able to restore and maintain normoglycemia. In contrast, human islet grafts were completely rejected following injection of HLA-mismatched human PBMC as evidenced by return to hyperglycemia and loss of human C-peptide in the circulation. Thus, PBMC engrafted NOD-scid IL2rγnull mice are able to provide an in vivomodel of a functional human immune system and of human islet allograft rejection. The enhanced ability of NOD-scid IL2rγnull mice to support human cell engraftment gave rise to the possibility of creating a model of graft versus host disease mediated by a human immune system. To investigate this possibility, human PBMC were injected via the tail vein into lightly irradiated NOD-scid IL2rγnull mice. We found that in contrast to previous models of GVHD using human PBMC-injected immunodeficient mice, these mice consistently (100%) developed GVHD following injection of as few as 5x106PBMC, regardless of the PBMC donor used. We then tested the contribution of host MHC in the development of GVHD in this model. As in the human disease, the development of GVHD was highly dependent on host expression of MHC class I and class II molecules. To begin to evaluate the extent to which the PBMC-engrafted NOD-scid IL2rγnull humanized mouse model of GVHD represents the clinical disease, we tested the ability of a therapeutic in clinical trials to modulate GVHD in these mice. In agreement with the clinical experience, we found that interrupting the TNFα signaling cascade with etanercept delayed the onset and severity of disease in this model. In summary, we conclude that humanized NOD-scid IL2rγnull mice represent an important surrogate for investigating in vivo mechanisms of both human islet allograft rejection and graft versus host disease.
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2

Watret, Karen Christine. "Graft-versus-host reaction and the mucosal immune response." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/19395.

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3

Carlens, Stefan. "Leukaemic relapse after allogeneic haematopoietic stem cell transplantation and the use of the graft-versus-leukaemia effect /." Stockholm, 2000. http://diss.kib.ki.se/2000/91-628-4310-9/.

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4

Desbarats, Julie. "Mechanisms of T cell immunosuppression during the graft-versus-host reaction." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28728.

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The studies presented in this thesis examine the mechanisms of T cell immunosuppression during the graft-versus-host reaction (GVHR). GVHR was induced by the injection of parental lymphoid cells into F1 hybrid recipient mice. The ensuing acute reaction consisted of an initial immunoproliferative phase, followed by the development of profound immunosuppression and histopathological lesions of epithelial and lymphoid tissues. Survivors of the acute reaction developed the persistent immune abnormalities characteristic of chronic GVHR.
We have found that the T cell protein tyrosine kinases p56$ rm sp{lck}$ and p59$ rm sp{fyn}$, involved in signal transduction through the T cell receptor (TCR), are downregulated in the T cells of mice during GVHR. The reduction of lck and fyn was prevented by adrenalectomy of the recipients, and a similar reduction could be induced in normal (non-GVH-reactive) mice by an injection of exogenous cortisone. These findings suggested that the GVHR-induced elevation in endogenous glucocorticoid levels could trigger the decrease of T cell lck and fyn, resulting in a T cell signalling defect during GVHR. In fact, we have demonstrated that glucocorticoids induced a decrease in lck and fyn in T cell clones in vitro. Thus, it appeared that the early GVHR-induced T cell unresponsiveness was due to the glucocorticoid-dependent downregulation of T cell lck and fyn.
We have investigated changes in T cell maturation and selection in the GVHR-dysplastic thymus, which may account for the persistent immune abnormalities of chronic GVHR. Thymocyte TCR expression and usage were aberrant during GVHR; changes included decreased expression of CD3 on CD4$ sp+$8 thymocytes, inconsistent TCR V$ beta$ usage, and appearance of phenotypically autoreactive mature thymocytes. These abnormalities, suggestive of defective positive and negative selection, are likely to result from the GVHR-induced decrease in thymic class II MHC expression. Altered T cell education may lead to the long-term peripheral T cell defects observed in chronic GVHR. Lastly, we report that GVHR-induced cutaneous injury was exacerbated by irradiation of the target tissue, suggesting that in clinical GVHR, irradiation may intensify tissue damage, including thymic epithelial lesions; this could potentially lead to more serious alterations in thymic function, and thus to longer lasting, more severe peripheral T cell immune deficiency.
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5

Peres, Amos. "Effects of an interferon inducer, pI:C, on the graft-versus-host reaction." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74294.

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Polyinosinic: polycytidylic acid (pI:C), an interferon (IFN) inducer, was used to investigate the role of IFN in the graft-versus-host reaction (GVHR), induced by injecting parental cells into F1 recipients and assessed for immunosuppression and pathological lesions.
PI:C-treatment of recipients, but not donors, before GVHR-induction suppressed the GVHR, an effect seen only with C57BL/6 (B6) and not A donor cells. Using fluorescein-labelled donor cells, pI:C-treatment was seen to cause a marked decrease in donor cell survival after 2 days. Elimination of donor cells was specific for the B6 donor, was associated with increased natural killer (NK) cell but not macrophage cytotoxic activity, was radioresistant and anti-asialo GM1 sensitive, evidence supporting NK-mediated rejection.
Plotting donor cell recovery against the number of cells injected into variously treated recipients indicated that in unstimulated mice a constant proportion of the injected cells were rejected, pI:C increasing that proportion, suggesting that pI:C changes F1 NK target repertoire.
PI:C-treatment after GVHR-induction increased the severity of the GVHR, especially soon after GVHR-induction, the effect waning afterwards. No strain dependence was observed.
These results demonstrate that IFN/IFN-activated cells play an important role in the regulation and in the immunosuppression/pathogenesis of a GVHR.
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6

Jaksch, Marie. "Molecular monitoring of acute graft-versus-host disease after allogeneic stem cell transplantation /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-987-0/.

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7

Li, Hu [Verfasser]. "Mechanisms of Glucocorticoids in the modulation of Graft-versus-Host Disease and the Graft-versus-Leukemia Reaction / Hu Li." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://d-nb.info/1215338570/34.

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8

Rotolo, Jimmy A. "Ceramide-mediated platform generation regulates apoptosis in vitro and in vivo /." Access full-text from WCMC:, 2007. http://proquest.umi.com/pqdweb?did=1428842781&sid=10&Fmt=2&clientId=8424&RQT=309&VName=PQD.

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9

Svahn, Britt-Marie. "Stem cell transplantation: home care, graft-versus-host disease and costs /." Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-611-5/.

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10

Ghimire, Sakhila [Verfasser], and Ernst [Akademischer Betreuer] Holler. "Analysis of the Immune Cell Infiltrates and Biomarkers during acute Gastrointestinal Graft vs Host Disease / Sakhila Ghimire ; Betreuer: Ernst Holler." Regensburg : Universitätsbibliothek Regensburg, 2016. http://d-nb.info/1122355769/34.

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11

Soares, Tânia Cristina Benetti 1978. "Análise das alterações microscópicas em glândulas salivares menores e fígado após o transplante alogênico de células tronco hematopoéticas." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288071.

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Orientadores: Maria Elvira Pizzigatti Corrêa, Cecília Amélia Fazzio Escanhoela
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: A doença do enxerto contra o hospedeiro crônica (DECHc) é um processo inflamatório aloimune o qual resulta da resposta celular (células T) do doador contra o receptor em pacientes tratados pelo transplante de células progenitoras hematopoiéticas (TCTH). Os órgãos mais afetados são pele, mucosa oral, glândulas salivares e fígado. O objetivo deste trabalho foi avaliar os achados histopatológicos das glândulas salivares menores (GSM) e fígado dos pacientes afetados pela DECHc, comparando-os entre si, com as amostras destes órgãos de pacientes que não desenvolveram DECHc pós TCTH e com pacientes que não foram tratados pelo TCTH. Amostras de GSM e fígado de pacientes tratados por TCTH mieloablativo, de doadores aparentados com HLA idêntico, entre 1994 e 2006, foram analisadas. Cinquenta e sete pacientes foram selecionados, sendo 36 com DECHc oral e hepática e 21 sem DECH. O diagnóstico de DECHc foi definido por critérios clínicos (extensa/localizada), laboratoriais e de seguimento. Amostras sem alterações de pacientes não transplantados também foram avaliadas (19 de GSM e 20 de fígado). Os espécimes foram corados em hematoxilina e eosina, ácido periódico de Schiff (PAS), Tricrômio de Masson, Reticulina e Perls e tratados pela técnica de imuno-histoquímica para CD45, CD45RO, CD68, CD4, CD8, CD138 e AE1/AE3. Os critérios definidos pela classificação proposta pelo grupo de trabalho em histopatologia da reunião de consenso do National Institutes of Health (NIH) foram empregados para a avaliação de todas as amostras de ambos os órgãos. Nos espécimes corados pelo PAS, foi tomada a medida da área acinar das GSM, em imagens digitalizadas. No fígado de pacientes que desenvolveram DECH, foi observado aumento estatisticamente significante do número de células imunomarcadas para CD8 e CD45RO, quando comparado ao dos outros 2 grupos...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital
Abstract: Chronic graft-versus-host disease (cGVHD) is an alloimmune inflammatory process, which results from a donor-origin cellular response (T cells) against host tissues. The organs mostly affected are skin, oral mucosa, salivary glands and liver. The aim of this study was to evaluate the histopathological findings of minor salivary glands (MSG) and liver of patients affected by cGVHD, comparing the findings each other and with those of the patients who did not develop cGVHD after HSCT and patients who were not underwent HSCT. MSG and liver samples from patients who underwent myeloablative HLA-matched HSCT from sibling donors, between 1994 and 2006, were analyzed. Fifty-seven patients were selected, being 36 with oral and hepatic cGVHD and 21 without GVHD. The diagnosis of cGVHD was defined through clinical/ laboratory criteria and follow-up. Samples from non-transplanted patients were also evaluated (19 MSG and 20 liver specimens). The specimens were stained with haematoxylin & eosin, periodic acid-Schiff (PAS), Masson's trichrome, reticulin and Perls, and immunolabeled for CD45, CD45RO, CD68, CD4, CD8, CD138, and AE1/AE3. The criteria defined in the classification proposed by the consensus meeting of the National Institutes of Health were used for the evaluation of all samples of both organs. Digital images of the PAS stained sections were used to estimate the MSG acinar area. In the liver of patients who developed GVHD it was observed a statistically significant increase in the number of CD45RO and CD8 immunostained cells, comparatively with the other 2 groups...Note: The complete abstract is available with the full electronic document
Doutorado
Patologia
Doutor em Estomatopatologia
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12

Moraes, Mara Cabral 1977. "Contribuição ao estudo da infusão de linfócitos do doador (ILD) em pacientes onco-hematológicos após transplante de células tronco hematopoiéticas (TCTH) alogênico." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310030.

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Orientador: José Francisco Comenalli Marques Júnior
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: INTRODUÇÃO: A ILD vem sendo utilizada como opção terapêutica para recaída de neoplasias hematológicas após transplante alogênico. Contudo, este procedimento não é isento de riscos e sua indicação deve ser criteriosa. Neste trabalho avaliamos a ILD quanto à eficácia da coleta; efeitos adversos para os doadores e pacientes e efeitos quanto à remissão da doença, redução de recaída e mortalidade. MÉTODOS: Foi realizado estudo retrospectivo dos pacientes (n=40) que receberam ILD, no Hemocentro da UNICAMP, de março 1995 a janeiro 2008, e dos respectivos doadores (n=40). As características dos pacientes, complicações e sobrevida foram comparadas a um grupo de pacientes (n=264) que realizou transplante alogênico e não recebeu ILD. RESULTADOS: As 54 coletas de linfócitos analisadas atingiram o alvo estabelecido de '10 POT. 7' CD3+/Kg receptor, sem nenhuma reação grave para os doadores. Não observamos diferença estatística na mortalidade (p= 0,85) ou incidência de DECHa (p=0,231) entre os grupos de pacientes. No entanto, as causas de óbito foram diferentes (p<0,001), com maior mortalidade por doença no grupo em estudo e por outras causas no grupo comparativo. A incidência de DECHc e remissão completa foram maiores no grupo comparativo (p<0,001), enquanto o tempo para o óbito foi maior no grupo em estudo (p=0,009). CONCLUSÕES: A coleta de linfócitos foi eficaz e segura para o doador. Para os pacientes a DECH se sobressaiu como efeito adverso, sem aumento após a ILD. Não foi observado aumento na remissão da doença ou queda na mortalidade após a ILD, contudo, o tempo para o óbito foi maior. Outros fatores e a heterogeneidade das amostras podem ter contribuído para os resultados encontrados
Abstract: BACKGROUND: Donor lymphocyte infusion (DLI) has been used as a therapeutic option for hematological recurrences after allogeneic transplantation. However, this procedure is not devoid of risks and its indication must be precise. In this article we assess DLI regarding collection efficacy; adverse effects in donors and patients and its impact on disease remission, recurrence induction and mortality. METHODS: A retrospective study of patients (n=40) who received DLI and their respective donors was performed at Hemocentro, UNICAMP, between March 1995 and January 2008. Patient characteristics, complications and survival were compared to a comparative group (n=264) consisting of patients who underwent allogeneic transplantation, but did not receive DLI. RESULTS: All the 54 lymphocyte collection procedures reviewed reached the set target of '10 POT. 7' CD3+/Kg receptor, with no serious adverse reactions to the donors. We did not observe statistical difference in mortality (p=0.85) nor in the incidence of acute GVHD (p=0.231) between the two patient groups. However, causes of death were statistically different (p<0.001), with a higher disease-related mortality rate in the study group and for other causes in the comparative group. Chronic GVHD incidence and complete remission were higher in the comparative group (p<0.001), while the overall survival was longer in the study group (p=0.008). CONCLUSIONS: Lymphocyte collection was efficient and safe to the donor. As for patients, GHVD was the most important side effect but did not have a higher incidence after DLI. We did not observe an increase in disease remission or decrease in mortality rate after DLI; however, overall survival was longer. Other factors and the sample heterogeneity might have contributed to the results observed
Mestrado
Clinica Medica
Mestra em Clínica Médica
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13

Rasmusson, Ida. "Immune modulation by mesenchymal stem cells /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-384-1/.

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14

Hentschke, Patrik. "Anti-tumour effect in solid tumours, tolerance and immune reconstitution after allogeneic haematopoietic stem cell transplantation /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-800-9/.

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15

Pidala, Joseph. "Achievement of Transplantation Tolerance: Novel Approaches and Mechanistic Insights." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5104.

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Current immune suppressive strategies fail to induce donor-recipient immune tolerance after allogeneic hematopoietic cell transplantation. Accordingly, patients suffer morbidity and mortality from graft vs. host disease (GVHD) and prolonged immune suppressive therapy. Biologic insight into transplantation tolerance is needed, and translation of such insight to novel clinical strategies may improve clinical outcomes. We report original investigation at seminal phases of this process including initial prophylactic immune suppression, onset of acute graft vs. host disease, and ultimate immune suppression discontinuation: In a controlled randomized clinical trial, we demonstrate that sirolimus-based immune suppression reduces risk for acute GVHD, ameliorates the severity of subsequent chronic GVHD, and supports reconstitution of functional regulatory T cells. Study of tissue-infiltrating CD4+ T cell subsets in acute GVHD target organs supports a pathogenic role for Th17 cells. Finally, we demonstrate that peripheral blood transcriptional biomarkers provide mechanistic insight into human transplantation tolerance. These data signal progress, and suggest rational translational efforts to achieve transplantation tolerance.
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16

Ebrahimi, Majid. "Studies of p63 and p63 related proteins in patients diagnosed with oral lichen planus." Doctoral thesis, Umeå : Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1437.

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17

Ortiz, Érica 1973. "Caracterização histopatlologica da mucosa nasossinual em pacientes transplantados de celulas tronco hematopoieticas (TCTH) sem e com doença do enxerto contra o hospeiro (DECH)." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/308575.

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Orientador: Carlos Takahiro Chone
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
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Resumo: A imunossupressão é a principal causa de rinossinusite recorrente no transplante de células tronco hematopoiéticas (TCTH) com uma incidência aumentada na Doença do Enxerto contra o Hospedeiro (DECH) pós-TCTH. Descrições histológicas de mucosas oral, pulmonar e intestinal associadas ao TCTH e a DECH têm sido descritas. Porem, para entender melhor a fisiopatogenia da resposta imune nos pacientes transplantados, verificou-se a histologia e ultraestrutura da mucosa nasossinusal dos pacientes TCTH com e sem DECH. O processo unciforme de 24 pacientes submetidos ao TCTH (19 com DECH e 5 sem) foi submetido à análise histológica através das microscopias óptica e eletrônica de transmissão (ME). A ME mostrou alterações na estrutura ciliar, quantidade de mitocôndria, microvilos e vacuolização citoplasmática. Todos os transplantados com rinossinusite apresentaram perda ou ausência significante de cílios (P=0.018). Corpúsculos apoptóticos estavam aumentados e células caliciformes, diminuídas no epitélio nasossinusal dos pacientes transplantados com DECH crônica (P=0.04). Esta destruição epitelial poderia facilitar a penetração bacteriana ou viral, desencadeando uma recorrência ou exacerbação da infecção.
Abstract: Immunosuppression is the leading cause of recurrent sinus infections following Hematopoietic Stem Cell Transplantation (HSCT) with increased incidence of sinusitis in patients with chronic graft versus host disease (GVHD) following HSCT. Histological descriptions of the oral mucosa, lung ciliary epithelium and intestinal mucosa related to HSCT and GVHD have been described. However, we sought to verify the histological and ultra structural aspects of nasal mucosa in patients following HSCT with and without GVHD in order to better understand the pathophysiology of the immune response. The uncinate processes from 24 HSCT (19 with GVHD, 5 without) patients were subjected to histological analyses via light and transmission electron microscopy (TEM). TEM revealed altered cilia structure, mitochondria quantity, microvilli, cytoplasm vacuolization. All HSCT patients with rhinosinusitis had significant loss or absence of cilia (P=0.018). Apoptotic bodies were increased and Goblet cells decreased in nasal epithelium from patients with chronic GVHD (P=0.04).This tissue destruction would facilitate the bacterial and viral penetration and may result in a recurrence or exacerbation of the infection.
Mestrado
Otorrinolaringologia
Mestre em Ciências Médicas
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18

Ortiz, Érica 1973. "Alterações histológicas nasossinusais no paciente transplantado de células tronco hematopoiéticas (TCTH) e na doença do enxerto contra o hospedeiro (DECH) crônica com rinossinusite." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312618.

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Orientadores: Ester Maria Danielli Nicola, Eulália Sakano
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: Introdução: Acredita-se que a imunossupressão seja única causa para maior prevalência de rinossinusites (RS) no transplantado de células tronco hematopoiéticas (TCTH) principalmente naqueles com Doença do Enxerto contra o Hospedeiro (DECH) crônica. Pacientes submetidos ao TCTH podem apresentar alterações nasossinusais, que podem se relacionar ao próprio transplante, assim como pelo regime de condicionamento ou pela DECH. Entretanto, estas alterações nasossinusais não estão bem descritas na literatura assim como a associação entre estas e a rinossinusite. Objetivo: verificar a histologia e ultraestrutura da mucosa nasossinusal com RS no TCTH com e sem DECH; e verificar a influencia da RS nas possíveis alterações histológicas nestes pacientes. Método: estudo prospectivo exploratório de coorte transversal com análise estatística de dados obtidos da avaliação de mucosa de processo unciforme de pacientes transplantados com (16) e sem DECH (8) com RS; através da microscopia eletrônica de transmissão e óptica. Comparação da recorrência das RS e alterações histológicas. Resultados: 47% (14) tiveram apenas 1 ou 2 episódios e 33%, mais de 3 episódios de rinossinusite. Apenas a presença de microvilosidades foi significativamente maior nos pacientes sem GVHD (p=0,05). Não houve diferença significativa na quantidade de cílios, ultraestrutura ciliar, metaplasia escamosa, células caliciformes, vacuolização citoplasmática, densidade do infiltrado inflamatório, linfócitos, eosinófilos e corpúsculos apoptóticos intraepiteliais, glândulas mucosas, espessura da membrana basal, edema e fibrose subepiteliais entre os grupos com e sem DECH. Houve diminuição significante de cílios conforme maior recorrência de rinossinusite (p=0,008). Conclusão: pacientes com RS e TCTH não apresentaram diferenças nas alterações histológicas nasossinusais, exceto aumento de microvilosidades naqueles sem a DECH. Os transplantados com e sem DECH apresentaram somente diminuição dos cílios conforme o aumento da recorrência de RS
Abstract: INTRODUCTION: It is believed that immunosuppression is the sole cause for the occurrence of rhinosinusitis in hematopoietic stem cell transplant (HSCT). There is a high incidence of sinusitis in recipient patients, especially in those with Chronic Graft-Versus-Host disease (GVHD). Histopathological abnormalities were described in recipients¿ sinus mucosa compared to immunocompetent patients. There were also mucosal abnormalities related to cytotoxicity in the transplanted patients with chronic GVHD but no difference in ultrastructure between HSCT patients with and without GVHD, except for increased goblet cells in patients without GVHD. The relation between the sinonasal mucosa abnormalities of patients with and without GVHD and rhinosinusitis is not well established yet. OBJECTIVE: To verify the ultrastructure of the sinonasal mucosa of HSCT with and without GVHD with rhinosinusitis to understand the cause of high sinusitis incidence in recipients with and without GVHD. METHOD: A prospective study with preliminary exploratory statistical analysis of data obtained from the evaluation of the uncinate process mucosa of patients transplanted with (16) and without GVHD (8) with rhinosinusitis by transmission electron and optical microscopy. RESULTS: Of the patients, 47% (14) had only 1 or 2 episodes, and 33% had more than 3 episodes of rhinosinusitis. Only the presence of microvilli was significantly higher in patients without GVHD. There was no significant difference in the amount of cilia, ciliary ultrastructure, squamous metaplasia, goblet cells, vacuolization, density of the inflammatory infiltrate, intraepithelial lymphocytes, eosinophils, mucous glands, apoptotic corpuscles intraepithelial basement membrane thickness, edema and subepithelial fibrosis between groups. There was a significant decrease of cilia with higher recurrence of rhinosinusitis. CONCLUSION: There was an increase in microvilli HSCT without GVHD with rhinosinusitis, and the ultrastructure and histological changes of HSCT with and without GVHD did not change with the recurrence of rhinosinusitis. However, there was a decrease of cilia in the epithelium of the sinonasal HSCT with higher recurrence of rhinosinusitis
Doutorado
Otorrinolaringologia
Doutora em Ciências Médicas
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19

Miranda, Eliana Cristina Martins 1965. "O impacto do evento competitivo após o transplante de células-tronco hematopoiéticas : comparação entre os métodos de incidência cumulativa e Kaplan-Meier." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/308626.

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Orientador: Carmino Antonio De Souza
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: O estudo analisa duas metodologias que estão sendo usadas para estimar a probabilidade de eventos. Um método é a inversão do Kaplan-Meier (1-KM), o qual não considera eventos competitivos, e o outro método é a função da incidência cumulativa (FIC). O estudo contemplou a definição do conceito de risco competitivo e a aplicação dos métodos citados em um conjunto de dados de pacientes submetidos ao transplante de células-tronco hematopoiéticas (TCTH). Os critérios de inclusão foram pacientes consecutivos transplantados no período de Janeiro de 1994 a Dezembro de 2010, com diagnóstico de leucemia aguda (LA) ou leucemia mieloide crônica (LMC). O evento de interesse foi a doença do enxerto contra o hospedeiro (DeCH) crônica, enquanto os eventos competitivos foram: recaída e morte prévia a DeCH crônica. O resultado após a aplicação do método 1-KM para o grupo de pacientes com LA foi de 52% e estratificado pelo tipo de enxerto foi 44% para medula óssea (MO) e 77% para sangue periférico (SP) p= 0.003. Quando aplicado o método FIC a probabilidade geral foi de 45% e por tipo de enxerto foi 17% para MO e 33% para SP, p= 0.00002. No grupo de pacientes diagnosticados com LMC, usando a mesma racional os resultados foram similares. Não há comparações entre os métodos estatísticos, principalmente porque o pressuposto de se considerar o evento competitivo é aplicado somente na metodologia FIC. A fonte de células SP cotejada com fonte de células MO conduzem a uma incidência cumulativa maior de DeCH, independente da doença de base. Os resultados apresentaram, na grande maioria, diferenças grandes entre os testes, indicando a importância de se averiguar os detalhes no momento da aplicação
Abstract: This study presents two methodologies that have been used to estimate the probability of events. One method is the Kaplan-Meier inversion (1-KM), which no consider the competitive events, and another one is the cumulative incidence function (CIF). The study showed the definition of competitive risk concepts and its application in the database of patients submitted to the hematopoietic stem cell transplantation (HSCT). Inclusion criteria were consecutive transplanted patients in the period between January 1994 to December 2010, with acute leukemia (AL) or chronic myeloid leukemia (CML). The interest event was chronic graft versus host disease (GVHD), insofar, competitive events were relapse or early death previous to chronic GVHD. The results after 1-KM application in the AL group was 52% and stratified by source of graft was 44% in bone marrow (BM) and 77% in peripheral blood (PB) with p=0.003. When CIF test applied the results was 45% and by source of graft was 17% in BM and 33% in PB, p= 0.00002. In the CML group the results were similar. There is no comparison between the statistical tests, mainly because their assumptions are not the same. PB as source of graft induces a higher incidence of chronic GVHD, independent of disease. All results presented, in the mayor, huge differences among the tests, indicating the importance to check the details at time of application
Doutorado
Clinica Medica
Doutora em Clínica Médica
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20

Feio, Patrícia do Socorro Queiroz 1982. "Estudo do proteoma salivar após transplante alogênico de células-tronco hematopoéticas." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288070.

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Orientador: Maria Elvira Pizzigatti Corrêa
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Apesar dos avanços, a doença do enxerto contra o hospedeiro (DECH) ainda é principal complicação pós-transplante alogênico de células-tronco hematopoéticas (alo TCTH), que limita sobrevida e induz maior morbidade nos pacientes. A descoberta de proteínas diferentemente presentes na DECH pode ser capaz de tornar o diagnóstico mais precoce e preciso, além de permitir melhor tratamento. Neste contexto, o estudo dos proteomas busca encontrar proteínas que funcionem como biomarcadores e a utilização da saliva para este fim apresenta vantagens por apresentar coleta não invasiva, indolor e de baixo custo. O objetivo deste estudo foi o de avaliar prospectivamente o proteoma salivar em pacientes submetidos ao alo TCTH e comparar a perfil das proteínas em pacientes que desenvolveram a DECH (DECH+) e os que não desenvolveram (DECH-), elaborando um painel de potenciais biomarcadores para esta doença. Foram incluídos neste trabalho 20 pacientes submetidos ao transplante alogênico de células-tronco hematopoéticas na Unidade de Transplante de Medula Óssea do Hospital de Clínicas da Unicamp. Todos os pacientes foram submetidos à avaliação odontológica e adequação do meio bucal quando necessário, além de serem avaliados para grau de mucosite, parâmetros clínicos de hipossalivação e avaliação das lesões orais de DECH. Foram coletadas amostras de saliva não estimulada em 3 períodos: pré-TCTH, no d+8-10 e d+ 80-100. Adicionalmente, foi avaliado o fluxo salivar dos pacientes em todas as coletas. Todas as amostras foram acondicionadas com inibidores de proteases para avaliação proteômica. A análise das amostras foi realizada por espectrometria de massas após digestão com tripsina e separação dos peptídeos por uma coluna reversa de nanocromatografia líquida. Os dados obtidos foram confrontados com o banco International Protein Index (IPI) human utilizando o software Mascot v.2.3.2.0 ® e os arquivos resultantes da busca foram carregados no software Scaffold ®. As proteínas que mostraram variação em razão de 100% (? 0,5 e >2) entre os grupos DECH+ e DECH- no período d+8-10 para d+80-100 foram consideradas significativas. Não houve correlação estatisticamente significativa dos parâmetros clínicos de hipossalivação com o grupo DECH+. Entretanto na avaliação longitudinal dos pacientes, a presença de saliva espessa e viscosa mostrou-se significativa (p = 0,003). Foram identificadas 69 proteínas nos pacientes avaliados, sendo as mais frequentes relacionadas à defesa e imunidade. No presente estudo, dez proteínas mostraram alteração no grupo DECH+, porém 4 estavam presentes em apenas uma amostra com a doença. Portanto, as proteínas Lactoferroxin-B, IGL@ protein, Submaxillary gland androgen-regulated protein 3B, Cystatin-SA, Cystatin-S e Prolactin-inducible protein foram consideradas como potencias biomarcadores para a doença do enxerto contra hospedeiro
Abstract: The graft-versus-host disease (GVHD) remains the major clinical complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT), limiting survival and inducing major morbity. Differently expressed proteins in GVHD have the potential of improving early and accurate diagnosis, also allow a better treatment. Proteome analysis is emerging for the discovery of proteins which function as biomarkers and saliva can be useful for this purpose because offers an easy, inexpensive, safe, and non-invasive approach. The aims of this study were to evaluate salivary proteome in patients underwent allo-HSCT and compare the proteins expressions between patients with and without GVHD and elaborate a panel of possible biomarkers for this condition. Twenty patients underwent allo- HSCT at the Bone Marrow Transplantation Unit - UNICAMP were enrolled in this study. Patients underwent dental evaluation before HSCT and oral environment stabilization were performed when necessary. Also, an evaluation of grade of mucositis, clinical signs of hyposalivation and oral GVHD lesions. Unstimulated saliva samples were collected on 3 different times: pre-HSCT, d+8-10 e d+ 80-100. Additionally, the unstimulated salivary flow rate was measured. Thus, these samples were stored with protease inhibitors for proteomic evaluation. The samples were analyzed by mass spectrometry after protein digestion with trypsin and peptides separated by a Reverse Phase-nanoUltra Perfomance Liquid Chromatography. Protein search was performed using the Mascot v.2.3.2.0 ® engine against International Protein Index (IPI) human Database and the output files of the searches were loaded onto Scaffold software ®. The proteins which showed 100% fold change (? 0,5 e >2) between d+8-10 and d+80-100 were significant. There was no statistically significant correlation of clinical parameters of hyposalivation with GVHD+ group. However in the longitudinal assessment of patients, the presence of thick and viscous saliva was significant (p = 0,003). Sixty nine proteins were identified and the majority was involved in defense and immunity. The results indicated ten proteins differentially expressed in GVHD+ group, but 4 were presented only in one sample with disease. Therefore, Lactoferroxin-B, IGL @ protein, Submaxillary gland androgen-regulated protein 3B, Cystatin SA, Cystatin-S and Prolactin-inducible protein were identified as potential biomarkers for graft-versus-host disease
Doutorado
Patologia
Doutora em Estomatopatologia
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21

Khairallah, Michel. "Etude physiopathologique de la reaction du greffon contre l'hote induite chez la souris par les antigenes mineurs d'histocompatibilite." Orléans, 1987. http://www.theses.fr/1987ORLE2008.

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22

Antunes, Milena Monteiro de Souza. "O envolvimento das glândulas salivares na doença do enxerto contra o hospedeiro: estudo bioquímico e análise proteômica." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/5/5133/tde-11092017-131500/.

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A doença do enxerto contra o hospedeiro (DECH) é uma complicação que ocorre após o transplante alogênico de medula óssea. A doença é mediada por células T do enxerto que atacam as células e os tecidos do receptor; um processo inflamatório, que ataca vários órgãos e tecidos, sendo este processo responsável por 15% das causas de óbito após o acometimento da doença. As citocinas estão envolvidas na ativação das células T citotóxicas e células natural killer (NK), que causam as lesões nas glândulas salivares e exibem características de morte celular com infiltração de linfócitos conduzindo à apoptose. É conhecido que as unidades secretoras das glândulas salivares, após serem acometidas pela DECH, não recuperam o seu status funcional e a presença do infiltrado inflamatório pode ser um fator importante na fibrose das glândulas salivares e outros tecidos. Há evidências de uma redução significativa do fluxo salivar nos pacientes com DECH e de alterações importantes na proteômica salivar (IgA, IgG, lactoferrina) e polimorfismos que modifiquem a síntese de proteínas que devem ser consideradas para a evolução do paciente. Consequentemente os pacientes apresentam redução de fluxo salivar, com perda variável das unidades secretoras glandulares, comprometendo a qualidade de vida e os resultados do transplante. E para melhor compreensão da DECH, contribuindo para o diagnóstico precoce e na conduta destes pacientes, o presente estudo determinou o perfil proteômico dos pacientes com a doença do enxerto contra o hospedeiro crônica e comparou com o perfil de proteínas dos pacientes submetidos ao transplante de células tronco hematopoiéticas em cinco diferentes períodos, por meio da coleta de saliva, uma técnica não invasiva, e análise proteômica; além de comparar o perfil com os grupos controles (Líquen plano oral e indivíduos saudáveis). Foram incluídos neste estudo o total de 23 pacientes submetidos ao transplante de células-tronco hematopoiéticas, na Unidade de Transplante de Medula Óssea do Hospital das Clínicas da Universidade de São Paulo. As amostras foram submetidas a análises prévias em gel de poliacrilamida contendo dodecil sulfato de sódio (SDS) e gel bidimensional (2-DE) para o conhecimento do perfil proteômico destes pacientes. As análises foram feitas por espectrometria de massa e os dados obtidos foram confrontados com banco de dados humanos. As proteínas do grupo dos pacientes com DECHc foram comparadas com o grupo controle de indivíduos saudáveis, por meio do heatmap, e ressaltamos as proteínas de maior abundância. Portanto 16 proteínas mostraram uma maior expressão, Ig gamma-1 chain C region; Isoform H14 of Myeloperoxidase; Isoform 2 of 14-3-3 protein Sigma; Fibrinogen beta chain; Alpha- 1-acidic glycoprotein 1; Isoform gamma-A of Fibrinogen gamma chain; Hemopexin; Keratin type I CK 14; Alpha-2-Macroglobulin; Thioredoxin; Complement C3; Vitamin D; Keratin type I CK16; Lactoperoxidase; Cystatin B e Neutrophil elastase. No entanto, ao comparamos estas proteínas com os diversos períodos analisados e os grupos controles, ressaltamos a importância de três proteínas para a doença do enxerto contra o hospedeiro crônica: Isoform 2 of 14-3-3 protein sigma, Hemopexin e CK14
Graft versus host disease (GVHD) is a complication that occurred after allogeneic bone marrow transplantation. The disease is mediated by graft T cells that attack as cells and tissues of the recipient; An inflammatory process, which attacks various organs and tissues, being responsible for 15% of the causes of death after the disease. Cytokines are involved in the activation of cytotoxic T cells and natural killer (NK) cells, which cause lesions in salivary glands and exhibit cell death characteristics with lymphocyte infiltration leading to apoptosis. It is known as the secretory units of the salivary glands, after being affected by GVHD, do not recover their functional state and the presence of the inflammatory infiltrate can be an important factor in the fibrosis of the salivary glands and other tissues. There is evidence of a significant reduction in salivary flow in patients with GVHD and significant changes in salivary protein (IgA, IgG, lactoferrin) and polymorphisms that modify a protein symptom that are considered for patient evolution. Consequently, patients with salary reduction, with variable loss of glandular secretory units, compromise quality of life and transplant results. In order to better understand GVHD, contributing to the early diagnosis and in the management of these patients, the present study determined the proteomic profile of patients with graft versus chronic host disease and compared them with the protein profile of patients submitted to cell transplantation Hematopoietic stem cells in five different periods, through the collection of saliva, a noninvasive technique and proteomic analysis; In addition to a profile with the control groups (Lichen planus oral and healthy individuals). Included in this study were the 23 patients submitted to hematopoietic stem cell transplantation in the Bone Marrow Transplantation Unit of the Hospital das Clínicas of the University of São Paulo. As samples were submitted to previous analyzes on polyacrylamide gel containing sodium dodecyl sulfate (SDS) and 2-dimensional gel (2-DE) to know the proteomic profile of these patients. The analyzes were done by mass spectrometry and the data obtained were compared with human data. The proteins of the group of patients with GVHDc were compared to the control group of healthy individuals by means of the Heatmap, and we emphasized as proteins of greater abundance. Therefore, 16 proteins show a greater expression, Ig gamma-1 chain C region; Isoform H14 of Myeloperoxidase; Isoform 2 of 14-3-3 protein Sigma; Fibrinogen beta chain; Alpha-1-acidic glycoprotein 1; Isoform gamma-A of Fibrinogen gamma chain; Hemopexin; Keratin type I CK 14; Alpha-2-Macroglobulin; Thioredoxin; Complement C3; Vitamin D; Keratin type I CK16; Lactoperoxidase; Cystatin B e Neutrophil elastase. Isoform 2 of 14-3-3 protein sigma, Hemopexin and CK14. Isoform 2 of 14-3-3 protein sigma, Hemopexin and CK14. However, when comparing these proteins with the various types of analyzes and the control groups, we emphasize the relevance of three proteins for the graft versus host disease: Isoform 2 of 14-3-3 protein sigma, Hemopexin and CK14
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23

Larsson, Kajsa. "Cytomegalovirus after allogeneic haematopoietic stem cell transplantation : complications in the era of CMV-specific antiviral treatment /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-735-5/.

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24

Cardozo, Daniela Maira 1984. "Importância das disparidades genéticas nos genes HLA e KIR na resposta de pacientes submetidos ao transplante alogênico de células progenitoras hematopoiéticas para o tratamento de doenças onco-hematologicas = Importance of genetic differences in HLA and KIR genes in the response of patients undergoing allogeneic hematopoietic stem cell transplantation for treatment of onco-hematological diseases." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/308649.

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Orientadores: Cármino Antonio de Souza, Jeane Eliete Laguila Visentainer
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: No organismo humano, as moléculas HLA (Human Leukocyte Antigens) são proteínas expressas na superfície da maioria das células nucleadas e são codificadas por genes localizados no braço curto do cromossomo 6 na região do Complexo Principal de Histocompatibilidade (CPH). Essas proteínas são caracterizadas pelo alto grau de polimorfismo, e também faz a ligação com receptores KIR (Immunoglobulin-like Receptors), expressos nas células Natural Killer. Os receptores KIR, que reconhecem moléculas do complexo HLA de classe I, estão entre os principais receptores inibidores dos linfócitos NK. Células infectadas por vírus e células tumorais perdem ou têm diminuída a expressão de moléculas HLA de classe I e, por isso, são eliminadas pela ausência de ligação entre moléculas HLA e receptores KIR inibitórios. Atualmente, muitos estudos têm destacado a importância dos genes KIR e HLA no Transplante de Células Progenitoras Hematopoiéticas (TCPH). O TCPH é o tratamento de escolha para muitas doenças hematológicas e dependem de vários fatores incluindo o estágio da doença, o regime de condicionamento, a fonte de células, o grau de identidade HLA entre doador e receptor e o desenvolvimento da doença do enxerto contra o hospedeiro (DECH). Estudos recentes indicam que a presença de células NK alorreativas no enxerto representa um fator favorável à recuperação de pacientes, uma vez que essas células têm a capacidade de eliminar células tumorais residuais pela ausência ou diminuição da expressão de moléculas HLA e sem a indução da DECH. Também outros fatores podem estar envolvidos na resposta pós-transplante, como a presença e ausência de determinados alelos HLA e genes KIR, os quais podem estar ligados à melhor ou pior resposta pós-transplante. O primeiro ensaio investigou a associação entre HLA e a ocorrência da DECH aguda e crônica em pacientes que receberam transplante de células progenitoras hematopoiéticas HLA-idêntico, aparentados. No total, foram 176 pacientes que receberam o primeiro transplante entre 1997 e 2009. DECH aguda foi positivamente associada ao HLA-A10 (P = 0.0007), HLA-A26 (P = 0.002), B55 (P = 0.001), DRB1*15 (P = 0.0211) e DQB1*05 (P = 0.038), enquanto que HLA-B16 (P = 0.0333) foi mais frequente em pacientes sem DECH aguda. DECH crônica foi positivamente associada com HLA-A9 (P = 0.01) e A23 (P = 0.0292) e negativamente associada com HLA-A2 (P = 0.0031) e B53 (P = 0.0116). HLA-B35 (P = 0.0373), B49 (P = 0.0155) e B55 (P = 0.0024) foi alta em pacientes com DECH aguda grau 3 ou mais, do que os outros pacientes. Nos pacientes com DECH crônica extensa, HLA-A9 (P = 0.0004), A24 (P = 0.0059) e A26 (P = 0.0411) foi maior do que nos outros pacientes, enquanto HLA-A2 foi baixo (P = 0.0097). O objetivo do segundo ensaio foi avaliar as possíveis interações dos genes KIR e HLA com o curso clínico do transplante HLA compatível, aparentado e não depletado de linfócitos T, particularmente na doença do enxerto contra o hospedeiro (DECH) aguda e crônica, recaída, sobrevida global e sobrevida livre de evento. A maioria dos doadores (78%) apresentaram o haplótipo B do KIR enquanto que 22% apresentaram o haplótipo A. Dos pacientes que receberam o haplótipo A do doador, 90% tiveram DECH, aguda ou crônica, comparados com os que receberam o haplótipo B (58%) (dados não estatisticamente significantes). Não houve diferença significativa para recaída entre pacientes que receberam os haplótipo A ou B (27% vs 23%). Não houve diferença no desenvolvimento da DECH e recaída para os pacientes homozigotos (C1C1 ou C2C2) e heterozigotos (C1C2) e nem para aqueles com HLA-Bw4 presente e ausente. Também, a sobrevida global não foi diferente para os grupos de pacientes analisados. No entanto, houve forte correlação entre o grupo de pacientes heterozigotos para HLA-C (C1C2) e a incidência de DECH aguda e recaída. A SLE foi maior nos pacientes heterozigotos que não desenvolveram DECHa (p<0,0001). Resultados mostraram que as variantes de HLA podem influenciar na ocorrência de DECH em transplante alogênico, com doadores relacionados, HLA-idênticos, tanto como fatores de proteção, quanto como fatores de susceptibilidade. Ainda, a interação KIR/HLA tem impacto significante no resultado dos transplantes relacionados, HLA compatível, sem depleção de linfócitos T, influenciando na incidência de recaída e na ocorrência da DECH. Resultados mostraram que para o grupo heterozigoto (C1C2) a maioria dos pacientes não desenvolveu DECH aguda e apresentou maior SLE, sugerindo um possível efeito protetor para esse grupo
Abstract: In the human organism, the HLA (human leukocyte antigens) are proteins expressed on the surface of most nucleated cells and are encoded by genes located on the short arm of chromosome 6 in the region of the Major Histocompatibility Complex (MHC). These proteins are characterized by a high degree of polymorphism, and also make the connection with KIR (Immunoglobulin-like Receptors), expressed in Natural Killer cells. KIR receptors that recognize HLA molecules of class I are among the major inhibitory receptors of NK-cells. Virus infected cells and tumor cells have lost or diminished expression of HLA class I molecules and therefore are eliminated by the absence of binding between HLA molecules and inhibitory KIR receptors. Currently, many studies have highlighted the importance of KIR and HLA genes in Hematopoietic Stem Cell Transplantation (HSCT). HPCT is the treatment of choice for many hematological malignancies and depends on various factors including stage of disease, the conditioning regimen, the source of cells, the degree of identity between donor and recipient HLA and development of chronic graft-versus-host (GVHD). Recent studies indicate that the presence of alloreactive NK cells in the graft is a factor aiding the recovery of patients, since these cells have the ability to eliminate residual tumor cells by the absence or diminution of expression of HLA molecules and without inducing GVHD. Also other factors may be involved in response post-transplant, as the presence or absence of certain HLA genes and KIR, which can be connected to a better or worse response after transplantation. The first trial investigated the association between HLA and the occurrence of acute and chronic GVHD in patients receiving hematopoietic stem cell transplant HLA-identical related. In total, 176 patients who received a first transplant between 1997 and 2009. GVHD was positively associated with HLA-A10 (P = 0.0007), HLA-A26 (P = 0.002), B55 (P = 0.001), DRB1 * 15 (P = 0.0211) and DQB1 * 05 (P = 0.038), while that HLA-B16 (P = 0.0333) was more frequent in patients without acute GVHD. Chronic GVHD was positively associated with HLA-A9 (P = 0.01) and A23 (P = 0.0292) and negatively associated with HLA-A2 (P = 0.0031) and B53 (P = 0.0116). HLA-B35 (P = 0.0373), B49 (P = 0.0155) and B55 (P = 0.0024) was high in patients with acute GVHD grade 3 or more, than the other patients. In patients with extensive chronic GvHD, HLA-A9 (P = 0.0004), A24 (P = 0.0059) and A26 (P = 0.0411) was greater than in the other patients, whereas HLA-A2 was low (P = 0.0097). The objective of the second test was to evaluate the possible interactions of KIR and HLA genes with the clinical course of the transplant HLA compatible related and not depleted of T lymphocytes, particularly in chronic graft versus host disease (GVHD) acute and chronic relapse, survival overall and event-free survival. Most donors (78%) presented the KIR B haplotype while 22% were haplotype A. Of the patients who received the donor haplotype A, 90% had GvHD, acute or chronic, compared with those who received the haplotype B (58%) (data not statistically significant). There was no significant difference in relapse between patients who received the haplotype A or B (27% vs 23%). There was no difference in the development of GVHD and relapse for patients homozygous (C1C1 or C2C2) and heterozygous (C1C2) and not for those with HLA-Bw4 present and absent. Also, the overall survival was not different for the groups of patients studied. However, there was strong correlation between the group of patients heterozygous for HLA-C (C1C2) and the incidence of acute GVHD and relapse. The SLE was higher in patients who did not develop GVHD heterozygotes (p <0.0001). Results showed that the HLA variants may influence the occurrence of GVHD in allogeneic transplantation with related donors, HLA-identical, both as protective factors, such as susceptibility factors. Furthermore, the interaction KIR / HLA has a significant impact on the outcome of transplantation related HLA-compatible, without depletion of T cells, influencing the incidence of relapse and the occurrence of GVHD. Results showed that for the heterozygous group (C1C2) most patients did not develop acute GVHD and showed higher SLE, suggesting a possible protective effect for this group
Doutorado
Clinica Medica
Doutora em Clínica Médica
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25

Galvao, Flávio Henrique Ferreira. "Modelo experimental de doença do enxerto versus hospedeiro após transplante de intestino delgado." Universidade de São Paulo, 1998. http://www.teses.usp.br/teses/disponiveis/5/5132/tde-13072011-171433/.

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A doença do enxerto versus hospedeiro (DEVH) é uma grave complicação do transplante de órgãos sólidos, com alta mortalidade. Seu estudo tem sido limitado pela carência de modelos experimentais apropriados. Descreve-se um modelo de DEVH baseado no aumento do quimerismo, sua evolução clínica, histopatológica, do número das células quiméricas, do perfil das citocinas e da tolerância imunológica. Ratos Lewis (LEW) foram submetidos a transplante simultâneo de intestino delgado e medula óssea provenientes de ratos ACI (grupo de estudo - E) ou LEW (grupo controle - C), tratados com FK-506 (1 mg/Kg/dia) entre o 0 e 13o PO, e uma dose semanal daí por diante. Os ratos foram divididos nos seguintes grupos: E1- 6 ratos sacrificados no 120o PO. E2- 8 ratos após apresentarem sinais clínicos graves de DEVH entre o 189o e o 271o PO. Como controle, ratos LEW foram receptores dos mesmos tipos de enxertos provenientes de ratos LEW, submetidos à mesma imunossupressão e foram assim divididos: C1- 6 ratos sacrificados no 120o PO, C2- 5 ratos sacrificados entre o 223o e o 270o PO. A citometria de fluxo foi realizada para quantificar a porcentagem das células linfóides de ACI doadores no sangue periférico nos E1, E2 em 6 períodos: 30o PO, 65o PO, 95o PO, 120o PO, 160o PO, 200o PO. Os animais foram examinados 2 vezes por semana à procura de sinais de DEVH (rash cutâneo, perda de peso, de pelo e hiperqueratose). No sacrifício dos animais do grupo E1 e C1, foram colhidas amostras de língua (LI), de linfonodos cervicais (LC), intestino delgado do receptor e do enxerto para análise das citocinas IL-2, IL-4, IL-6, IL-10, IFN-gama e TNF-alfa por meio da reação em cadeia da polimerase. Em todos os grupos foram também colhidas amostras destes órgãos para histopatologia e nos animais do grupo E2 linfonodos cervicais foram processados para análise da reatividade celular por meio da reação mista dos linfócitos (MLR). A evolução clínica e histopatológica foi graduada de 0 a 3 de acordo com a severidade dos sintomas e do infiltrado mononuclear das amostras. Os ratos dos grupos E1 e E2 iniciaram sinais da DEVH entre o 84o e 115o PO. Os ratos dos grupos C1 e C2 não apresentaram evidência de DEVH. Amostras de LI e LC dos ratos do grupo E1 apresentaram alterações histopatológicas grau 2 e do grupo E2 apresentaram alterações histopatológicas grau 3, respectivamente. Nenhuma alteração histopatológica foi encontrada nos ratos do grupo controle e em amostras do ID. Nenhuma alteração histopatológica foi encontrada no intestino delgado do receptor e do enxerto. O aumento da porcentagem de células do doador no sangue periférico do receptor foi progressivo chegando a 5,4±2.3% no 10o período, 21±4,6% no 3o período e 39,3±4% no 6o período. IL-2, IL-6, IL-10, IFN-gma e TNF-alfa estiveram aumentados em língua e IL-4, IL-6, IL-10, IFN-gama e TNF-alfa em linfonodos cervicais. Os linfócitos de ratos do grupo E2 mostraram hiporreatividade aos de ratos ACI e hiperreatividade aos de ratos PVG (terceira parte) denotando tolerância imunológica. Neste modelo experimental há uma inexorável evolução imunológica para DEVH; existe correlação direta entre o aumento do quimerismo em sangue periférico e da expressão de citocinas em língua e linfonodos cervicais e a severidade da DEVH, além da indução de tolerância imunológica do rato do grupo E2 quimérico ao rato ACI normal.
Graft-versus-host disease (GVHD) has been a major concern after small bowel transplantation (SBTX) and the lack of suitable experimental models has limited the study of GVHD after solid organ transplantation. Here we describe a re1evant experimental model of GVHD after fully allogeneic SBTX based on chimerism augmentation, its clinical and histophatological evolution, cytokine involvement, responsible donor cell and immunologic tolerance analysis. LEW rat recipients received orthotopic SBTX and simultaneous donor bone marrow cell infusion (250x106), from ACI rats (experimental group - E) or LEW (control group C). FK-506 was administered dayly at a dose of 1 mg/kg on day 0 to 13, then continued as a weekly injection of same dose until the experimental end point. The recipients were divided in the following groups: E1 - 6 rats sacrificed at 120° POD. E2 - 8 rats sacrificed with critical GVHD between DPO 189 to 271. LEW recipient of LEW grafts, under the same immunossupression were used as control and divided as: C1 - 6 rats sacrificed at POD 120; C2- 5 rats sacrificed between 223 and 270 POD the number of donor cell in the recipient circulation was determined by flowcytometry in 6 pos-operative time: 30, 65, 95, 120, 160, 200. The rats were analyzed twice a week for body weigh and searching for signs of GVHD (cutaneous rush, hiperkeratosis and loss of hair and body weigh). At the sacrificed, samples from tongue (TG), cervical lymph node (CLN), donor (SBD) and recipient (SBR) small bowel were taken from all animals for histophatology and from E1 and C1l animals for IL-2, IL-4, IL-6, IL-10, IFN-gama e TNF-alfa cytokines analysis using reverse transcription polymerase chain reaction. Samples from cervical lynph nodes of 5 animals from group E2 were used for mixed lymphocyte reaction for tolerance analysis. The clinical and histophatological evolution of the disease were evaluated from degree 0 to 3 according to the severity. GVHD in E1 and E2 animals started between 84 and 115 POD. Histophatological analysis of TG and CLN showed that E1 animals present GVHD grade 2 and E2 animals grade 3. The increase of donors cells in the recipient circulation was progressive and account for 5.4± 2.3% at POD 30, 21.4±4.6% at POD 95 and 39.3±4% at POD 200. IL-4, IL-6, IL-10, IFN-gama e TNF-alfa were upregulated in CLN and IL-2, IL-6, IL-10, IFN-gama e TNF-alfa were upregulated in TG when compared with the respective controls. The lymphocytes from E2 group showed hyporeactivety to lymphocytes of normal ACI and hypereactivety to those of PVG, meaning tolerance. No cytokines alteration was noted in SBD neither SBR. Animals from group C1 and C2 did not present any sign of disease. This result show that GVHD is a inexoravel evolution under the experimental conditions of this study and the evolution of the disease is near correlated with the augmentation of the donor cells in the recipient circulation and upregulation of cytokines gene expression in target organs. Tolerance to the same donor strain lynphocytes was also noted.
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26

Normanton, Marília. "Estudo da interação das células-tronco mesenquimais e linfócitos no modelo da doença do enxerto contra hospedeiro." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/5/5146/tde-22092014-163529/.

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Uma das principais complicações inerentes ao transplante de células-tronco hematopoiéticas é a doença do enxerto contra hospedeiro (DECH), que se trata da resposta imunológica contra os tecidos do receptor pelas células T do doador contidas no transplante. Este quadro é responsável por 15-30% das mortes que ocorrem após o transplante de células-tronco hematopoiéticas alogênicas. Apesar dos recentes avanços para reduzir a incidência de DECH através de alternância de regimes profiláticos reduzindo a intensidade do condicionamento, são poucos os tratamentos efetivos. Recentemente, o potencial imunomodulador das células-tronco mesenquimais tornou-se o foco de vários estudos. Alguns autores descreveram a atuação destas células na redução da resposta imunológica através da inibição da proliferação de células T, representando um novo potencial terapêutico para DECH. Mediante esse conhecimento, investigamos o papel das células-tronco mesenquimais na proliferação, apoptose e na produção de citocinas por linfócitos T. Nossos resultados mostraram que a presença de células-tronco mesenquimais nas culturas regulam negativamente a proliferação de linfócitos T estimulados de forma independente de contato e a apoptose de forma parcialmente dependente de contato. Observamos também que linfócitos T virgens em diferenciação para Th17 na presença de células-tronco mesenquimais apresentam redução na capacidade de produzir duas importantes citocinas efetoras implicadas na DECH, o interferon gama (IFN-y) e a interleucina 17A (IL-17A). Investigamos se a prostaglandina E2 (PGE2), por depletar triptofano, estava envolvida com a diminuição de proliferação de linfócitos T quando em cultivo com células-tronco mesenquimais. Utilizamos nas culturas a indometacina (IDT), um anti-inflamatório bloqueador de cicloxigenase (COX 1 e 2) e portanto da via da PGE2. Entretanto, observamos que o bloqueio da via da PGE2 inibia ainda mais a proliferação de linfócitos T e isto ocorria de acordo com a dose de IDT. Com o resultado deste experimento concluímos que, se a proliferação de linfócitos é inibida pela depleção de triptofano do meio, ela não ocorre via PGE2. Entretanto ainda não conseguimos esclarecer se esta via é ativada por outras moléculas, ou se é esta a via realmente responsável pela inibição da proliferação de linfócitos. No que concerne a via de inibição de apoptose, mostramos que a cadeia alpha do receptor de IL-7 (CD127) está aumentada na superfície de linfócitos T quando em presença de células-tronco mesenquimais. Verificamos que o bloqueio de IL-7 nas culturas aumenta a apoptose em linfócitos, bem como sua adição causa diminuição de apoptose. Identificamos a produção intracelular de IL-7 nas células-tronco mesenquimais, relacionando estas células e IL-7 com a inibição de apoptose em linfócitos T nestas condições. Este trabalho gerou dados que permitiram a compreensão de alguns possíveis mecanismos pelos quais as MSCs podem atuar sobre linfócitos T ativados e/ou alorreativos; mecanismos estes que podem ser utilizados como base para futuras investigações na elucidação e prevenção da DECH
A major complication after hematopoietic stem cell transplantation is the graft versus host disease (GVHD), which is an immunological response of transplanted donor T cells against the recipient tissues; this outline is responsible for 15-30% of deaths that can occur after allogeneic hematopoietic stem cells transplant. Despite recent advances in reducing GVHD incidence by alternating prophylactic regimens, thus reducing the intensity of conditioning, there are few effective treatments. Recently, the immune modulatory potential of mesenchymal stem cells has become the focus of several studies. Some authors described the role of these cells in reducing immune response by inhibiting T cell proliferation, representing a potential new therapy for GVHD. Through this knowledge, we investigated the mesenchymal stem cells role into T lymphocytes proliferation, apoptosis and cytokine production. Our results showed that the presence of mesenchymal stem cells into the cultures downregulates the proliferation of stimulated lymphocytes independent of contact and apoptosis of stimulated lymphocytes in partially contact-dependent manner. We also observed during naive T lymphocytes differentiation into Th17 cells, that the mesenchymal stem cell presence reduces the lymphocyte ability in producing the GVHD major effectors cytokines, interferon gamma (IFN-y) and interleukin-17A (IL-17A). We investigated whether prostaglandin E2 (PGE2) was involved in the reduction of T lymphocytes proliferation, when cultured with mesenchymal stem cells, by tryptophan depletion. Indomethacin (IDT), an anti-inflammatory drug blocker of cyclooxygenase (COX 1 and 2) and therefore PGE2 pathway, was used. However, we observed that, according to IDT dose, blocking this pathway further inhibited lymphocyte proliferation. With this result we conclude that if lymphocyte proliferation is inhibited by tryptophan depletion, it does not occur via PGE2. However, we still cannot say whether this pathway is activated by other molecules, or if this pathway is actually responsible for T lymphocytes proliferation inhibition. Regarding the apoptosis inhibition in T lymphocytes, we show that the IL-7 receptor alpha chain (CD127) is increased on the surface of T lymphocytes when in the presence of mesenchymal stem cells. We found that IL-7 blockage in the cultures increases apoptosis in T lymphocytes, as well as their addition causes apoptosis decrease. We also identified the intracellular production of IL-7 on mesenchymal stem cells, linking these cells and IL-7 directly with apoptosis inhibition in T lymphocytes under these conditions This work has generated data that allowed the understanding of some possible mechanisms by which MSCs can act on activated and/or alloreactive T lymphocytes; mechanisms that can be used as a basis for future research in the elucidation and prevention of GVHD
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27

Rocha, Luís Klaus Alves da. "Avaliação da reconstituição da função tímica e a caracterização das subpopulações de linfócitos T e do perfil de citocinas em pacientes submetidos ao transplante alogênico de células-tronco hematopoiéticas que desenvolveram doença do enxerto-contra-hospedeiro." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/5/5146/tde-27092018-093454/.

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O transplante de células-tronco hematopoiéticas tem sido a melhor opção terapêutica para muitas doenças. Seu sucesso, no entanto, depende de alguns fatores que influenciam a taxa de mortalidade. A doença do enxerto-contra-hospedeiro é uma causa de mortalidade. Apresenta duas formas, a aguda e a crônica, e ambas têm linfócitos T na patofisiologia. Outra causa são as infecções, cujos patógenos variam conforme o tempo de recuperação do sistema imune. O presente estudo avaliou a recuperação linfoide T com base no timo e distinção das subpopulações e citocinas nos pacientes que desenvolveram doença do enxerto-contra-hospedeiro crônica no primeiro ano de transplante. Os pacientes foram alocados no Hospital de Transplante Amaral Carvalho (Jaú/SP) e tinham entre 18 e 60 anos de idade. No pré-transplante, foram comparados com indivíduos saudáveis, pareados em idade. Após o transplante, todos os pacientes foram acompanhados por um ano e seis meses, para observação de possíveis eventos de doença do enxerto-contra-hospedeiro e/ou infecções. A análise laboratorial foi feita com o sangue do paciente, sendo a primeira antes do transplante, seguidas por mais quatro, com intervalos de três meses. Tais avaliações laboratoriais tinham por objetivos caracterizar a função tímica por quantificação de sjTREC; as subpopulações de linfócitos T, por citometria de fluxo e a análise de citocinas, por Luminex. Foram estudados 172 indivíduos, sendo 75 do transplante alogênico, 43 do transplante autólogo, além de 54 pessoas saudáveis. Nossos resultados mostraram que os pacientes apresentaram função tímica diminuída antes mesmo da realização do transplante. A função tímica enfraquecida foi um fator de risco para doença do enxerto-contrahospedeiro crônica e a recuperação do sistema imune foi melhor nos pacientes que não apresentaram doença do enxerto-contra-hospedeiro crônica após um ano do transplante. No entanto, a função tímica não foi diferente entre os pacientes que faleceram e os que estão vivos. No geral, não houve distinção quanto à apresentação das subpopulações de linfócitos T e à produção de citocinas entre os pacientes submetidos ao transplante alogênico que desenvolveram doença do enxerto-contra-hospedeiro crônica, relativamente aos demais pacientes. Com o tempo, foi observada a recuperação gradual do compartimento linfoide T e diminuição na incidência de infecções. A taxa de infecções não influenciou a apresentação das subpopulações de linfócitos T e a produção de citocinas nos pacientes que desenvolveram doença do enxerto-contrahospedeiro crônica em relação aos demais pacientes. Como conclusão, a função tímica apresentou-se deteriorada antes da realização do transplante, porém não foi determinante para que houvesse piora na evolução clínica após o transplante. Os pacientes que desenvolveram doença do enxerto-contra-hospedeiro crônica, independentemente da incidência de infecções, apresentaram semelhança no perfil das subpopulações de linfócitos T e das citocinas, quando comparados aos demais
Hematopoietic stem cell transplantation has been the best therapeutic option for many diseases. Its success depends on some factors that influence the mortality rate. Graftversus- host disease is one cause of mortality. It has two forms, acute and chronic, and both have T lymphocytes in their pathophysiology. Other causes are infections, whose pathogens vary according to immune system recovery time. The present study evaluated the lymphoid T recuperation through the thymus and the differentiation of subpopulations and cytokines in patients who developed chronic graft-versus-host disease at the first year of transplantation. The patients were allocated at Hospital de Transplantes Amaral Carvalho (Jaú/SP). They were between 18 and 60 years old. At pre-transplant phase, patients were compared to healthy individuals, age-matched. After transplantation, they were all assisted for one year and six months, so that graft-versushost disease\'s and infections\' events could be observed. The laboratory analysis was done by blood sample; the first occurred before the transplant, followed by four more, every three months. Laboratory examinations were performed to characterize thymic function by quantification of sjTREC; T lymphocyte subpopulations, by flow cytometry, and cytokine analysis, by Luminex. A total of 172 individuals were studied: 75 allogeneic transplant patients, 43 autologous transplant patients and 54 healthy persons. Our results showed that patients presented thymic function impaired even before the transplant. The weakening of the thymic function was a risk factor for chronic graft-versus-host disease and immune system recovery was better in patients who did not develop chronic graft-versus-host disease after one year of transplantation. However, the thymic function was not different between patients who died and those who remained alive. In general, there was no distinction of the presentation of T lymphocyte subpopulations and cytokines production among patients who underwent allogeneic transplant and developed chronic graft-versus-host disease, in comparison to the other patients. Over time, a gradual recovery of the T lymphoid compartment and a decrease in the infections incidence were observed. The infection rate did not influence the presentation of the T lymphocyte subpopulations and the production of cytokines in patients who developed chronic graft-versus-host disease in comparison to the other patients. In conclusion, the thymic function was impaired before transplantation, but it was not relevant for clinical evolution worsening after transplantation. Patients who developed chronic graft-versus-host disease, regardless of the incidence of infections, showed similar profile of T lymphocytes subpopulations and cytokines, relatively to other patients
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28

Seung, Edward. "CD40-CD154 Blockade Facilitates Induction of Allogeneic Hematopoietic Chimerism and Transplantation Tolerance: A Dissertation." eScholarship@UMMS, 2003. https://escholarship.umassmed.edu/gsbs_diss/103.

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Allogeneic hematopoietic chimerism leading to central tolerance has significant therapeutic potential. Establishment of hematopoietic chimerism created by stem cell transplantation has been shown to prevent and cure a number of autoimmune diseases and induce the most robust and long-lasting form of transplantation tolerance known. However, the realization of the vast clinical potential of hematopoietic chimerism for induction of transplantation tolerance has been impeded by the toxicity of the host conditioning regimen and the development of graft-versus-host disease (GVHD). This thesis describes the development of stem cell transplantation protocols that 1) reduce the host conditioning regimen; and 2) abrogate the development of GVHD. When applied to the treatment of autoimmune diabetic NOD mice, a model of type 1 diabetes, stem cell transplantation was able to 3) prevent autoimmune recurrence; and 4) permit curative pancreatic islet transplantation. I first describe a tolerance-based stem cell transplantation protocol that combines sub-lethal irradiation with transient blockade of the CD40-CD154 costimulatory pathway using an anti-CD154 antibody. With this protocol, I established hematopoietic chimerism in BALB/c mice transplanted with fully allogeneic C57BL/6 bone marrow. All chimeric mice treated with anti-CD154 antibody remained free of graft vs.host disease (GVHD) and accepted donor-origin but not third party skin allografts. It was similarly possible to create allogeneic hematopoietic chimerism in NOD/Lt mice with spontaneous autoimmune diabetes. Pancreatic islet allografts transplanted into chimeric NOD/Lt mice were resistant not only to allorejection but also to recurrence of autoimmunity. I conclude that it is possible to establish robust allogeneic hematopoietic chimerism in sub-lethally irradiated mice without subsequent GVHD by blocking the CD40-CD154 costimulatory pathway using as few as two injections of anti-CD154 antibody. I also conclude that chimerism created in this way generates donor-specific allograft tolerance and reverses the predisposition to recurrent autoimmune diabetes in NOD/Lt mice, enabling them to accept curative islet allografts. In order to further reduce the impediments associated with the implementation of allogeneic hematopoietic chimerism as a therapeutic modality, I adapted a costimulation blockade-based protocol developed for solid organ transplantation for use in stem cell transplantation. The protocol combines a donor-specific transfusion (DST) with anti-CD154 antibody to induce peripheral transplantation tolerance. When applied to stem cell transplantation, administration of DST, anti-CD154 antibody, and allogeneic bone marrow led to hematopoietic chimerism and central tolerance with no myeloablation (i.e. no radiation) and no GVHD in 3 different strains of mice. The development of donor-specific tolerance in this system was shown to involve deletion of both peripheral host alloreactive CD8+ T cells and nascent intrathymic alloreactive CD8+ T cells. In the absence of large numbers of host alloreactive CD8+ T cells, the cell transfusion that precedes transplantation need not be of donor-origin, suggesting that both allo-specific and non-allo-specific mechanisms regulate engraftment. Agents that interfere with peripheral transplantation tolerance partially impair establishment of chimerism. I conclude that robust allogeneic hematopoietic chimerism and central tolerance can be established in the absence of host myeloablative conditioning using a peripheral transplantation tolerance protocol.
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29

Bueno, Nadjanara Dorna. "O transplante de células tronco hematopoéticas alogênico e autogênico na leucemia mielóide aguda em primeira remissão completa: análise de 62 pacientes." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/5/5164/tde-19062008-172259/.

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O transplante de células tronco hematopoéticas alogênico e autogênico na leucemia mielóide aguda em primeira remissão completa: analise de 62 pacientes. Os pacientes foram submetidos a transplante de células tronco hematopoéticas alogênico e autogênico. Ao final do estudo estavam vivos no alogênico 43,3% e no autogênico 62,5%. Consolidação intensiva teve melhor sobrevida no alogênico. Os pacientes com DECH aguda grau II tiveram melhor sobrevida. Dois pacientes com DECH crônica extensa morreram. Óbito por infecção ocorreu com maior freqüência no alogênico seguido de recidiva. No autogênico a recidiva foi a principal causa de óbito. Morte por toxicidade ocorreu em 47% dos pacientes que foram a óbito no alogênico e em 8,3% no autogênico. Na analise múltipla de Cox a consolidação intensiva e DECH crônica, tiveram significância.
The allogeneic and autologous hematopoietic stem cell transplantation in acute myeloid leukemia in first complete remission: analyses of 62 patients. The patients were submitted to allogeneic and autologous hematopoietic stem cell transplantation. The end of the study were kept alive in allogeneic 43,3% and in autologous 65,2%. Patient in allogeneic who were consolidated had better survival. Patients with acute GVHD grade II had better survival. Two patients with chronic GVHD in intense, died. Infection was the most frequent dead cause in allogeneic following relapse. In autologous the relapse was the principal cause of death. Toxicity occurred in 47% of patients who died in allogeneic and 8,3% in autologous. In cox multiple analyses intensive consolidation and chronic GVHD had significance.
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30

Gaspar, Frederico Manuel Gomes Forte Portugal. "Chronic graft-versus-host disease : second line therapy review." Master's thesis, 2017. http://hdl.handle.net/10451/31315.

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Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2017
Graft-versus-Host disease (GVHD) is a complication of bone marrow transplant. It has two forms: acute and chronic. In this work we’ll only address the chronic one (cGVHD). cGVHD is a very frequent complication of the transplant (up to 50% of the patients) and a major one, given its high mortality rate, being the main cause of death in these patients, apart from the recurrence of the primary malignancy. Even thought our understanding of GVHD is far from complete, some progresses are being made. Firstly, the disease itself is being defined differently, being no longer just a temporal division between the acute GVHD (if occurred in the first 100 days after the transplant) and the chronic form (after the 100 day mark) but a more precise distinction based on the clinical manifestations, which are different between both forms. Even more, new criteria to evaluate the manifestations and the overall severity of the cGVHD have been developed, reflecting the advances in this area and enabling a better management of the patients. cGVHD treatment is very complex and far from perfect. Nowadays, the first approach relies on Corticosteroids plus a Calcineurin inhibitor. However, this treatment option has a limited efficacy (with 10% of the patients without any improvement and less than 50% only with a partial response). So, many of the patients will require second line therapy, however this isn´t perfect either. Even though there is a vast amount of options and in constant update, the number of studies is small and in many times the results aren´t satisfactory, making the clinical decision very hard and relying in a “trial and error” approach. So, with all this in mind, we develop this work in order to address every single one of these second line therapies and make some conclusions regarding them.
A Doença de Enxerto-vs-Hospedeiro (DEVH) é uma complicação decorrente do transplante de medula óssea. A DEVH pode ser dividida em forma crónica e aguda sendo que neste trabalho apenas iremos desenvolver a apresentação crónica (DEVHc). Esta é uma complicação não só extremamente frequente (até 50% dos recetores de transplante) mas também muito importante, dada a sua grande mortalidade, sendo a principal causa de morte nestes doentes, excluindo a recorrência da doença de base. Apesar de o nosso conhecimento sobre a DEVH ainda estar incompleto, já estão a ser feitos avanços. Em primeiro lugar, a própria conceção da DEVH alterou-se, passando de uma mera divisão temporal entre a forma aguda (caso se manifestasse nos primeiros 100 dias após o transplante) e a forma crónica (após o centésimo dia) para uma divisão baseada nas manifestações clínicas, que são diferentes entre ambas. Ainda mais, surgiram recentemente novos critérios de avaliação das manifestações e gravidade da DEVHc que refletem este avanço na compreensão da doença e possibilitam uma melhor avaliação dos doentes. O tratamento da DEVHc é complexo e longe se ser o ideal. Atualmente, a terapêutica inicial consiste em Corticoterapia associada a um inibidor da Calcineurina, no entanto, esta opção apresenta apenas uma eficácia limitada (com 10% dos doentes sem qualquer resposta e menos de 50% apenas com melhoria parcial). Assim, muitos doentes necessitam de terapêutica de segunda linha. No entanto, esta também não é perfeita pois, embora exista uma variedade considerável de terapêuticas possíveis e em constante atualização, estas estão pouco estudadas e muitas vezes apresentam resultados pouco satisfatórios, sendo a escolha entre estas difícil e muitas vezes baseada numa abordagem de “tentativa e erro”. Assim, é neste contexto que é desenvolvido este trabalho, com o objetivo de desenvolver cada uma destas terapêuticas de segunda linha e tecer considerações sobre estas.
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31

Li, Hu. "Mechanisms of Glucocorticoids in the modulation of Graft-versus-Host Disease and the Graft-versus-Leukemia Reaction." Doctoral thesis, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-1441-B.

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