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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.
171

Burden and Needs of Patients with Severe GvHD from the Supportive and Palliative Care Perspective—A Literature Review

Wenzel, Freya, Pralong, Anne, Holtick, Udo, Scheid, Christoph, Herling, Marco, Simon, Steffen T. 26 April 2023 (has links)
Graft-versus-host disease (GvHD) is a frequent, and often life-threatening, complication after an allogeneic, hematopoietic stem cell transplantation (allo-SCT). It can appear in an acute or a chronic form and presents different grades of severity. Particularly, the severe forms of GvHD are often responsible for a change of the curative intent for allo-SCT into a palliative goal of care. For this non-systematic review, we conducted a focused literature search in the MEDLINE database via PubMed to examine whether patients with severe forms of GvHD might have special needs and burdens from a supportive and palliative care perspective. To draw a comprehensive picture of this patient group, we included findings on quality of life (QoL) and physical symptoms and function as well as psychological and spiritual well-being. In most domains, patients with severe forms of GvHD showed greater impairment and a higher symptom burden compared to patients with milder forms of GvHD. However, we could not identify any studies that specifically investigated patients with severe forms of GvHD. Further research in this field is necessary to guarantee the highest standard of care for this very special patient group.
172

Les cellules dendritiques plasmacytoides dans le sang de cordon et après greffe de sang de cordon

Charrier, Emily 08 1900 (has links)
La greffe de sang de cordon est de plus en plus utilisée et a permis de traiter avec succès chez l’enfant des déficits immunitaires ainsi que des hémopathies malignes comme les leucémies. Malgré d’importants avantages tels que l’absence de risque pour le donneur ou la plus faible incidence de maladie du greffon contre l’hôte (GvHD), utiliser le sang de cordon comporte certains inconvénients. En effet, une reconstitution immunitaire retardée, des infections opportunistes en plus grand nombre et un risque de rechute sont des complications qui peuvent survenir et engendrer un risque pour le pronostic vital du patient. Par conséquent, de nouvelles stratégies d’immunothérapies doivent être envisagées. Dans le cadre de ce travail, nous nous sommes particulièrement intéressés aux cellules dendritiques plasmacytoides (pDC) dont les fonctions sont importantes pour l’initiation des réponses immunitaires innée et adaptative et particulièrement pour leur capacité à activer les cellules NK. Afin d’élucider le rôle et l’impact de ces cellules dans les greffes de sang de cordon, le nombre et la fonction des pDC et des NK a été suivi longitudinalement chez des patients ayant subi une greffe de sang de cordon comparativement à des patients transplantés avec de la moelle osseuse. Nous avons ainsi démontré que les pDC et les NK apparaissent précocement suite à une greffe de sang de cordon et que ces cellules sont fonctionnelles. Ces résultats mettent donc en lumière que ces cellules pourraient être de bons outils pour l’établissement d’une immunothérapie après greffe de sang de cordon. De plus, la caractérisation fonctionnelle des pDC du greffon de sang de cordon a permis de révéler une plus faible production d’IFN-α par les pDC, comparativement aux pDC de sang d’adulte. Cette différence pourrait jouer un rôle dans la plus faible incidence de GvHD après les greffes de sang de cordon. Dans le but de préciser les mécanismes moléculaires de régulation négative de la production d’IFN-α par les pDC de sang de cordon, nous avons étudié les protéines de la voie de signalisation TLR9-IRF7. L’expression similaire de l’ARN du TLR9, MyD88, IRAK1 et IRF7 contraste avec la plus faible expression des protéines correspondantes. De plus, l’expression des MicroARNs miR-146a et miR-155 est plus élevé dans les pDC de sang de cordon comparativement aux pDC de sang d’adultes. Ensemble, ces données pointent une régulation négative post-transcriptionnelle de la voie TLR9-IRF7 qui pourrait expliquer la plus faible production d’IFN-α des pDC du sang de cordon. L’ensemble des ces travaux suggère que les pDC pourraient représenter une cible de choix dans le développement de nouvelles approches thérapeutiques dans les greffes de sang de cordon. / Umbilical cord blood transplantation has increasingly been used as a source of hematopoietic stem cells to successfully treat immunodeficiencies and malignant diseases such as leukemia in pediatric patients. Despite important advantages, namely lack of risk for the donor and low incidence of GvHD, use of cord blood is associated with several drawbacks. Specifically, delayed immune reconstitution, more opportunistic infections and a relative risk of relapse are complications that may occur and lead to a poor prognosis. Consequently, new immunotherapeutic strategies should be considered. In this study, we were interested in plasmacytoid dendritic cells (pDC), whose functions are important for initiation of innate and adaptive immune responses and, in particular, for their ability to activate natural killer cells (NK). In order to elucidate the role and the impact of these cells in cord blood transplantation, pDC and NK numbers and function have been longitudinally followed in cord blood and bone marrow recipients. We showed that pDC and NK cells appeared early after umbilical cord blood transplantation and that these cells retained functional activity. Thus, these cells may constitute a good tool for immunotherapy in umbilical cord blood transplantation. Moreover, the functional characterization of pDC in cord blood revealed a lower production of IFN-α by cord blood pDC, which may play a role in the lower incidence of GvHD after umbilical cord blood transplantations. In order to determine the molecular mechanism for the negative regulation of IFN-α production by cord blood pDC, we studied the expression of TLR9-IRF7 pathway. The stable expression of TLR9, MyD88, IRAK1 and IRF7 mRNA contrasts with the lower expression of corresponding proteins. Interestingly, expression of microRNA miR-146a and miR-155 is higher in cord blood pDC. Together, these results point to a post-transcriptionnal negative regulation of TLR9-IRF7 pathway which may explain the lower IFN-α production by cord blood pDC. This work reinforces the idea that pDCs constitute a target of choice for developing new therapeutic approaches in cord blood transplantations.
173

Neogênese de células T e B em pacientes com doença falciforme tratados com diferentes modalidades terapêuticas / Neogenesis of T and B cells in patients with sickle cell disease treated with different therapeutic modalities

Jarduli, Luciana Ribeiro 06 April 2018 (has links)
As doenças falciformes (DF) constituem um grupo de doenças hereditárias monogênicas. São doenças extremamente relevantes no contexto de saúde pública no Brasil, portanto diferentes estratégias terapêuticas devem ser avaliadas. As oclusões vasculares afetam praticamente todos os órgãos, inclusive o baço e a medula óssea, porém não existem dados na literatura se estas comprometem também o tecido tímico. Os pacientes apresentam maior suscetibilidade às infecções cujas causas não são ainda totalmente esclarecidas Embora as infecções observadas nos pacientes sejam atribuídas à disfunção esplênica, o quadro inflamatório crônico e possíveis alterações no timo e na medula óssea, também poderiam causar uma disfunção imunológica. O objetivo deste trabalho foi avaliar a neogênese de células T e B e a diversidade do repertório de células T periféricas em pacientes com anemia falciforme (AF) sem tratamento (N = 15), tratados com hidroxiuréia (N = 20) ou transfusão crônica (N = 21) e em pacientes com DF tratados com transplante de células-tronco hematopoéticas (TCTH) alogênico (N = 29). Pacientes sem tratamento apresentaram menores níveis de sjTREC e ?-TREC, e menor taxa de divisão celular intratímica, demonstrando alterações importantes na neogênese das células T. A produção tímica de novas células T naïve foi reestabelecida em um ano pós-transplante, com normalização dos níveis de sjTREC e ?-TREC. O desenvolvimento de doença do enxerto contra o hospedeiro (DECHa) e reativação de citomegalovírus comprometeu a timopoiese nos primeiros seis meses pós-transplante, com diminuição significativa dos níveis de sjTRECs e ?-TRECs. Análises do repertório da cadeia V? dos receptores de células T (TCRs), pelo método TCRBV CDR3 spectratyping, indicaram que os pacientes com AF apresentaram um repertório menos diverso, composto predominantemente de famílias V? com padrão skewed e picos de CDR3 monoclonais, sendo a família V?3 mais frequente. A composição do repertório de células T foi alterada após o transplante, adquirindo um perfil mais policlonal dos picos de CDR3 ao longo do tempo. A família V?22 foi a mais expressa no período pré-transplante e em todos os seguimentos pós-transplante. Os pacientes com DF apresentaram aumento de linfócitos B naive, demonstrado pelos altos níveis de sjKRECs e pela taxa de proliferação homeostática. As análises multivariadas demonstraram que as alterações esplênicas influenciam diretamente os níveis de sjKREC, indicando que a baixa função esplênica leva ao aumento da produção de células B naive pela medula óssea, sugerindo um mecanismo compensatório. Os resultados desse trabalho demonstraram a existência de um desequilíbrio na neogênese de células T e B e consequentemente nesses compartimentos celulares periféricos, que pode conferir aos pacientes com DF uma maior susceptibilidade a infecções. Entre as diferentes modalidades terapêuticas, o TCTH alogênico sobressaiu-se em relação aos tratamentos convencionais, melhorando a neogênese de células T e B a longo prazo. / Sickle Cell Disease (SCD) are a group of monogenic hereditary diseases. These are extremely relevant diseases in the context of public health in Brazil, thus, different therapeutic strategies must be studied. Vascular occlusions affect practically all organs, including the spleen and bone marrow. However, there are no literature data about the impact of vaso-occlusions on the thymic tissue. Patients are more susceptible to infections whose causes are not fully elucidated. Although the infections observed in these patients are assigned to splenic dysfunction, the chronic inflammatory state and possible alterations of the thymus and bone marrow could also lead to immune dysfunction. The goal of this work was to evaluate the neogenesis of T and B cells and the diversity of peripheral T cell repertoire in patients with sickle cell anemia (SCA) without treatment (N = 15), treated with hydroxyurea (N = 20) or chronic transfusions (N = 21) and in patients with SCD treated with hematopoietic stem cell transplantation (N = 29) allogeneic. Patients without treatment had lower levels of sjTREC and ?-TREC, and lower rate of intrathymic cell division, demonstrating important alterations in the neogenesis of T cells. The thymic production of new naïve T cells was reestablished at one-year post transplantation, with normalization of sjTREC and ?-TREC levels. The development of graft-versus-host disease (aGVHD) and cytomegalovirus activation compromised thymopoiesis in the first six months post transplantation, with a significant decrease of sjTRECs and ?-TRECs levels. Analysis of the TCR V? chain repertoire by TCRBV CDR3 spectratyping indicate that patients with SCA showed a less diverse repertoire, mainly composed by V? families with a skewed pattern and monoclonal CDR3 peaks, being the V?3 family the most frequent one. The composition of the T-cell repertoire was altered after transplantation, changing over time to more polyclonal profile of the CDR3 peaks. The V?22 family was the more expressed at pre-transplantation and at all follow-up periods. Patients with SCD presented increased numbers of naive B cells, demonstrated by higher levels of sjKRECs and homeostatic proliferation. Multivariate analysis demonstrated that splenic function directly influenced sjKREC levels, indicating that compromised splenic function leads to increase of naive B cell output by the bone marrow, suggesting a compensatory mechanism. The results of this study showed the existence of an imbalanced T and B cell neogenesis and, consequently on these peripheral cell compartments, which may confer to patients with SCD an increased susceptibility to infections. Among different therapeutic modalities, allogeneic HSCT stood out in relation to the conventional treatments, improving long-term T and B cell neogenesis.
174

Avaliação da função tímica em pacientes com diabetes mellitus tipo 1 submetidos ao transplante autólogo de células-tronco hematopoéticas / Evaluation of thymic function in type 1 diabetes mellitus patients following autologous hematopoietic stem cell transplantation.

Azevedo, Júlia Teixeira Cottas de 19 August 2013 (has links)
O diabetes mellitus tipo 1 (DM-1) é uma doença autoimune órgão-específica caracterizada pela destruição seletiva das células pancreáticas produtoras de insulina. A imunossupressão em altas doses seguida do transplante autólogo de células-tronco hematopoéticas (TACTH) constitui uma alternativa terapêutica recente e promissora para o DM-1 recém-diagnosticado, impedindo a progressão da destruição das células pancreáticas produtoras de insulina e induzindo independência insulínica por um período prolongado na maioria dos pacientes. O princípio dessa terapia baseia-se na eliminação das células autorreativas pela imunossupressão intensa e na reconstituição de um sistema imunológico novo e tolerante após o transplante. Com o objetivo de avaliar a função do timo e sua contribuição na geração do repertório de células T nos pacientes com DM-1 após o TACTH, nesse trabalho foram avaliados os níveis de T cell receptor excision circles (TRECs) em células T do sangue periférico e a diversidade do repertório de células T dos pacientes com DM-1 (n=23) antes e em diversos períodos após o transplante. A quantificação absoluta dos níveis de TRECs (número de moléculas de TRECs/100g de DNA) foi realizada pela técnica de PCR em tempo real e a avaliação do repertório de células T foi realizada pela técnica de TCRBV CDR3 Spectratyping. Dentre os vinte e três pacientes, vinte alcançaram a independência insulínica por períodos variáveis de tempo e três não responderam ao tratamento. Não foi observada a restrição do repertório de células T nos pacientes com DM-1 no período pré-transplante, ou seja, quando recém-diagnosticados. Foram identificadas cinco famílias V (7, 18, 19, 20 e 22) em expansão clonal nos pacientes com DM-1. As famílias V 7, 18, 19, 20 apresentaram-se em expansão clonal antes do transplante e se mantiveram com frequência elevada após o transplante, enquanto a família V 22 apresentou aumento da frequência somente nos períodos mais tardios após o transplante. Nos primeiros meses após o transplante, houve redução do número de moléculas de TRECs e restrição do repertório de células T. Contudo, um ano após o transplante, o número de moléculas de TRECs atingiram valores normais e o repertório de células T apresentou-se com ampla diversidade. Nossos resultados mostraram que o TACTH foi capaz de induzir mudanças na composição do repertório de células T dos pacientes com DM-1 após a terapia de IAD/TACTH, evidenciadas por alterações qualitativas e quantitativas dos picos de CDR3 do TCR, sugerindo a reconstituição de um repertório de células T diverso até dois anos pós-transplante. Embora tenha ocorrido reativação da função tímica após o transplante, evidenciada pelo aumento dos níveis de TRECs de um ano e meio a cinco anos pós-transplante, a diversidade do repertório das células T diminuiu a partir de dois anos e meio pós-transplante, sugerindo uma reconstituição tímica de novo de células T naive que expressam preferencialmente algumas cadeias V. Estas evidências imunológicas poderiam explicar a melhora clínica (independência insulínica) temporária observada na maioria dos pacientes após a terapia de IAD/TACTH. / Type 1 diabetes mellitus (T1D) is an organ-specific autoimmune disease characterized by insulin-producing pancreatic cell destruction. High-dose immunosuppression followed by autologous hematopoietic stem cell transplantation (AHSCT) is a recent and promising therapeutic approach for treatment of T1D, preventing the progress of destruction of pancreatic cells and inducing insulin independence for a prolonged period in most patients. The rationale of the AHSCT is based on the elimination of autoreactive cells by the intense immunosuppression and on the reconstitution of a new and tolerant immune system after transplantation. Aiming at assessing the thymic role in the production of new T cell repertoire in T1D patients after AHSCT, in this study was evaluated the levels of T cell receptor excision circles (TRECs) in T cells of peripheral blood as well as the clonality and diversity of T cell repertoire in T1D patients (n=23) before and several periods after transplantation. The absolute quantification of TRECs levels (number of molecules of TRECs/100ng of DNA) was performed by real-time PCR and the analysis of T cell repertoire was performed by TCRBV CDR3 Spectratyping. Among the twenty-three patients, twenty achieved insulin independence for variable periods and three did not respond to the treatment. The T cell repertoire in T1D patients was not restricted in pre-transplantation, i.e., when newly diagnosed. It was identified five V families (7, 18, 19, 20 e 22) in the clonal expansion in T1D patients. The V families 7, 18, 19, 20 were in clonal expansion before transplantation and maintained with high frequency after transplantation, whereas the V 22 family increased its frequency only in the later periods after transplantation. It was observed that the numbers of molecules of TRECs decreased and the T cell repertoire was restricted in the early months after transplantation. However, the levels of TRECs were normalized and the T cell repertoire showed diversity one year after transplantation. Our results indicate that AHSCT was able to induce changes in the composition of the T cell repertoire of patients after AHSCT, evidenced by qualitative and quantitative changes in the composition of T-cell receptor -chain CDR3 peaks, suggesting the reconstitution of diverse T cell repertoire up to two years after transplantation. Although there was reactivation of thymic function after transplantation, as evidenced by increased levels of TRECs from one and a half year to five years after transplantation, the diversity of the T cells repertoire decreased from two and a half years after transplantation, suggesting a reconstruction of new naive T cells that preferentially express some V chains. These immunological evidences could explain the temporary clinical improvement (insulin independence) observed in most patients after IAD / AHSCT therapy.
175

Alterações bucais em pacientes submetidos ao transplante de células tronco hematopoiéticas: estudo longitudinal / Oral complications in patients undergoing hematopoietic stem cell transplantation: a longitudinal study

Luiz, Ana Cláudia 03 May 2012 (has links)
A boca é local de frequentes complicações relacionadas ao transplante de células tronco hematopoiéticas (TCTH) tais como xerostomia, disgeusia, disfagia, mucosite, infecções oportunistas e doença do enxerto contra hospedeiro (DECH). Sabe-se que estas complicações podem comprometer a qualidade de vida do paciente e interferir na morbidade pós-TCTH. O dentista é o profissional da saúde que deverá intervir no momento correto para tratar e minimizar esses efeitos secundários do TCTH. Para tanto é importante conhecermos o momento em que cada complicação ocorre para que a intervenção seja pronta e eficiente. O objetivo principal deste estudo foi identificar e quantificar as alterações bucais em indivíduos submetidos ao TCTH em cinco momentos consecutivos desde antes do início do condicionamento pré-TCTH até o dia 100 pós-TCTH. Como objetivos secundários buscamos investigar possíveis relações entre a severidade da mucosite oral e a manifestação da DECH com dados demograficos (sexo, idade), com o status de saude bucal (por meio dos índices IHO-S, CPOD, número de dentes cariados) e com a realização de adequação bucal pré-TCTH, e ainda, somente para a DECH, também foi investigada a possível relação entre esta doença com infecção sistêmica por citomegalovírus e com a manifestação de mucosite oral severa. Foram incluídos no estudo 27 indivíduos com doenças hematológicas do Serviço de Transplante de Medula Óssea do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP), com idade 12 anos que receberam TCTH alogênico. Os indivíduos foram examinados em cinco momentos consecutivos. No primeiro momento, pré-TCTH, foi realizada a coleta de índices de saúde bucal e aplicação de questionário sobre o histórico de tratamentos odontológico prévios. Nos momentos de 10, 20, 60 e 100 dias pós-TCTH foram avaliadas as manifestações bucais presentes. A incidência de mucosite oral foi de 82,6% considerando todos os momentos avaliados. Mucosite oral severa, ou seja, graus 3 e 4 (OMS) foi observada em 57,9% dos pacientes avaliados nos momentos 2 e 3. Dez (37%) pacientes apresentaram GVHD em algum órgão, e destes, 8 (80%) apresentaram GVHD de boca. Infecção sistêmica por CMV foi diagnosticada em 6 (22,2%) pacientes. Concluímos que entre as queixas levantadas, dor bucal e disfagia foram as mais referidas. O período de maior incidência das complicações bucais foi nos segundo e terceiro momentos, ou seja, D+10 e D+20, representando deste forma, o período de maior morbidade do tratamento. Não houve associação entre a severidade de mucosite oral e idade, sexo, fonte de células, regime de condicionamento, número de dentes cariados, IHO-S, CPOD e preparo bucal pré-TCTH. Para a DECH a única relação encontrada foi para fonte de células, tendo sido observada menor chance de ocorrer DECH quando a fonte de células foi o sangue periférico. / The mouth is a well-known site of complications of the hematopoietic stem cell transplantation (HSCT) such as dry mouth, dysgeusia, dysphagia, mucositis, opportunistic infections and graft versus host disease (GVDH). It is known that these complications can compromise the patients quality of life and morbidity post-HSCT. The dentist is the health professional who should interfere at the right time to treat and minimize these side effects of HSCT. Thus, it is important to know the time at which each complication occurs to be dynamic and efficient. The main objective of this study was to identify and quantify the oral complications in patients treated with HSCT in five consecutive moments starting before conditioning chemotherapy until day 100 post-HSTC. As secondary objectives we seek to investigate possible relationships between the severity of oral mucositis and the manifestation of GVHD with demographic data (gender, age), with the oral health status (IHO-S, CPOD, number of decayed teeth) and dental treatment previously HSCT, and, only for GVHD, was also investigated the possible relationship between this disease with systemic cytomegalovirus infection and the manifestation of severe oral mucositis. It was included in the study 27 patients with hematologic diseases who were admitted in the Unit of Bone Marrow Transplantation, Hospital of Clinics, Faculty of Medicine, University of Sao Paulo (HC-FMUSP), 12 years old whom received allogeneic HSCT. The subjects were examined in five consecutive moments. At the first moment, before HSCT, the oral health índex evaluation and a questionnaire about history of previous dental treatments were performed. Besides that, 10, 20, 60 and 100 days after HSCT they were evaluated for oral manifestations. Oral mucositis incidence was 82,6% and 57,9% of these patients presented severe mucositis. Ten (37%) patients had GVHD in any organ, and of these, 8 (80%) had oral GVHD. Infection by CMV was diagnosed in 6 (22.2%) patients. We conclude that among the complaints raised, mouth pain and dysphagia were the most mentioned. The period of increased incidence of oral complications was the second and third times (D +10 and +20), representing the increased morbidity period. There was no association between the severity of oral mucositis and age, sex, cell source, conditioning regimen, number of decayed teeth, IHO-S, CPOD and dental treatment pre-HSCT. For GVHD the only relation found was with source of cells, in which, GVHD was less likely to occur when the source of cells was peripheral blood.
176

IInfluência do Pegivirus humano (HPgV) na medula óssea: impacto clínico e tropismo viral / Human Pegivirus (HPgV) influence on bone marrow: clinical impact and viral tropism

Dias, Juliana Zanatta de Carvalho 01 February 2019 (has links)
O HPgV (Pegivirus Humano), conhecido anteriormente por GBV-C, causa infecção assintomática, persistente e com alta carga viral. Sendo o vírus de RNA sem patologia associada mais prevalente no mundo até os dias de hoje, os estudos in vitro ainda não foram capazes de mimetizar a replicação in vivo, permanecendo pouco esclarecidos vários aspectos de sua biologia. Estudos em macacos mostraram que os órgãos responsáveis pela maior replicação viral são o baço e a medula óssea, no entanto as células específicas permissíveis à infecção ainda não foram determinadas. Na década de 90, o HPgV ganhou notoriedade por diminuir os efeitos patológicos do HIV e aumentar a sobrevida de pacientes coinfectados HIV/HPgV, através da diminuição da ativação do sistema imune. Devido a essa característica, diversos estudos tentaram associar a presença de viremia a doenças hematológicas e um deles mostrou que a viremia de HPgV parece estar associada com o desenvolvimento de linfoma não- Hodgkin, porém muitas variáveis de confusão parecem influenciar esse resultado. Em conjunto, os dados mostram que o HPgV pode ter influência sobre a maturação e liberação de células progenitoras da medula óssea e, portanto, tornou-se primordial avaliar o impacto da viremia em pacientes com doenças hematológicas e definir o tropismo viral. Para tanto, o presente trabalho analisou a dinâmica de exposição à viremia de HPgV em pacientes submetidos ao transplante de células-tronco hematopoiéticas (HSCT), em cadáveres autopsiados pelo Sistema de Verificação de Óbitos da Capital de São Paulo (SVOC-SP) e em pacientes submetidos à cirurgia de artroplastia pelo Instituto de Ortopedia e Traumatologia (IOT) do HCSP. A carga viral de HPgV foi mensurada por qRT-PCR em Tempo Real levando em consideração valores adquiridos com um curva padrão desenvolvida para este trabalho. Para os pacientes HSCT, o efeito da presença de viremia antes e após o procedimento foi avaliada quanto aos principais desfechos do transplante: doença enxerto-hospedeiro aguda (aGVHD), recaída da doença hematológica primária e mortalidade. Para amostras SVOC e IOT, células específicas dos tecidos (cérebro, fígado, baço, linfonodo, medula óssea e sangue) foram avaliadas quanto à quantidade de RNA viral de polaridade positiva e negativa, a fim de quantificar a replicação e definir o tropismo do vírus. Os resultados mostraram que a prevalência de HPgV encontrada nos pacientes HSCT foi maior do que em estudos similares: 42% para as amostra pré- HSCT e 31% para as amostras pós-HSCT; porém, para as amostras SVOC, a prevalência foi menor do que o esperado: 1,2%. A presença de alta carga viral de HPgV em pacientes HSCT foi associada com aumento da taxa de incidência de aGVHD (95% CI 1,05-5,37, p=0,038). Dada a alta prevalência de HPgV na população brasileira, é essencial confirmar esse achado em outras coortes, de modo a determinar se o monitoramento do HPgV pode beneficiar o cuidado a esses pacientes. Nas amostras SVOC e IOT, a medula óssea apresentou maior número de populações celulares com replicação viral, com destaque para as células B progenitoras e para as células dendríticas. Porém, devido às condições da coleta e do processamento das amostras, o tipo celular permissível à infecção não pôde ser identificado com clareza, portanto fazendo-se necessária a coleta de um número maior de amostras SVOC / HPgV (Human Pegivirus), previously known as GBV-C, causes asymptomatic, persistent and high viral load infection. To date, it is the most prevalent RNA virus without associated pathologies in the world, yet in vitro studies have not yet been able to mimic the in vivo replication, consequently many aspects of its biology remaining unclear. Studies in non-humam primatas have shown that the organs responsible for the greatest viral replication are spleen and bone marrow, however the specific cells permissible for infection have not yet been determined. In the 1990s, HPgV gained notoriety by decreasing the pathological effects of HIV and increasing the survival of coinfected HIV/HPgV patients, by decreasing the activation of the immune system. Because of this characteristic, several studies have attempted to associate the presence of viremia with haematological diseases, and one has shown that HPgV appears to be associated with the development of non-Hodgkin\'s lymphoma, but many confounding variables still seems to influence this outcome. Together, the data show that HPgV may influence the maturation and release of bone marrow progenitor cells and therefore it has become crucial to evaluate the impact of HPgV viremia in patients with haematological diseases and to define viral tropism. Therefore, the present study analyzed the dynamics of HPgV viremia exposure in patients submitted to hematopoietic stem cell transplantation (HSCT), in cadavers autopsied by the São Paulo City Death Verification System (SVOC-SP) and in patients submitted to arthroplasty surgery by the Orthopedics and Traumatology Institute (IOT) of the Clinics Hospital of Sao Paulo. The HPgV was identified by real-time qRT-PCR and the viral load quantification was estimated by a standard curve developed for this work. For HSCT patients, the effect of viremia before and after the procedure was evaluated for the main transplant outcomes: acute graft vs host disease (aGVHD), relapse of primary haematological disease and mortality. For SVOC and IOT samples, tissue-specific cells (brain, liver, spleen, lymph node, bone marrow and blood) were evaluated for the amount of viral positive and negative RNA strains, in order to quantify replication and define virus tropism. The results showed that the prevalence of HPgV found in HSCT patients was higher than in similar studies: 42% for pre-HSCT samples and 31% for post-HSCT samples; however, for SVOC samples, the prevalence was lower than expected: 1.2%. The presence of high viral load of HPgV in HSCT patients was associated with an increase in the incidence rate of aGVHD (95% CI 1.05-5.37, p = 0.038). Given the high prevalence of HPgV in the Brazilian population, it is essential to confirm this finding in other cohorts, in order to determine if HPgV monitoring can improve the care of these patients. In the SVOC and IOT samples, the bone marrow presented a higher number of cell populations with viral replication, especially the progenitor B cells and the dendritic cells. However, due to the conditions of specimen collection and processing, the major permissible cell could not be clearly identified, thus making it necessary to collect a larger number of SVOC samples
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Reconstitution immunitaire et immunothérapie adoptive anti-virales après allogreffe de cellules souches hématopoiétiques / Anti-viral immune reconstitution and adoptive immunotherapy after hematopoietic stem cell transplantation

Rothé, Lamia 23 July 2010 (has links)
L’allogreffe de cellules souches hématopoïétiques (CSH) est un traitement efficace des Hémopathies malignes. Cependant, les complications des allogreffes parmi lesquelles les infections virales sont associées parfois à une morbidité et une mortalité importantes. Ces infections surviennent en l’absence de reconstitution immunitaire. Un monitoring régulier de la charge virale des principaux agents infectieux impliqués est réalisé mais amène parfois à la mise en oeuvre abusive de traitements anti-viraux qui ne sont pas dénués de toxicité.Dans ce travail, nous proposons d’associer à ce monitoring un suivi régulier de la reconstitution immunitaire spécifique afin de cibler parmi les patients présentant une réactivation ceux qui nécessitent un traitement curatif de ceux qui pourront maîtriser l’infection par leur système immunitaire. Nous illustrons ce propos avec le virus d’Epstein Barr (EBV) et avons en cours une étude sur l’Adénovirus (ADV).Dans certains cas parfaitement ciblés, les traitements anti-viraux s’avèrent inefficaces. C’est pourquoi dans ce travail, nous présentons la mise au point d’une technique de grade clinique de production de lymphocytes T cytotoxiques anti-ADV (CTL anti-ADV) en condition GMP (Good Manufacturing Practice), grâce au système CliniMACS et au Cytokine Capture System de Miltenyi, afin de proposer une immunothérapie adoptive.Nous décrivons par la suite trois expériences cliniques de traitement compassionnel d’une infection ADV post-allogreffe de CSH. Enfin, nous présentons les résultats préliminaires de la production de CTL bispécifique anti-ADV et CMV / Hematopoietic stem cells Transplantation (HSCT) is a well recognized strategy for treatment of haematological malignancies. However, HSCT complications among which the viral infections a reassociated with high morbidity and mortality. These infections arise in the absence of immune reconstitution. Monitoring of viral reactivations after allogeneic HSCT is necessary, to identify patients at risk of viral infections, but not sufficient, as patients may be abusively treated. In this work we propose to combine viral DNA load assessment with specific immune monitoring to target patients who need to be treated. We report a retrospective study investigating EBV infection and EBV-specific immune recovery using the functional IFN Elispot assay in 40 allogeneic HSCT patients. We initiated a similar study with ADV which is pending. However, although patients are correctly targeted, anti-viral treatment is sometimes not effective. We present a study on the development of a complete clinical grade generation of Human anti-Adenovirus cytotoxic T cells in GMP (Good Manufacturing Practice) conditions, thanks to the system CliniMACS and the Cytokine Capture System, to propose an adoptive immunotherapy to the recipient.We describe afterwards three clinical experiments of treatment of an ADV infection after HSCT.Finally, we present the preliminary results of the anti-ADV and -CMV bi-specific CTL production.
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Immunothérapie adoptive pour le traitement des infections à Adénovirus réfractaires après allogreffes de Cellules Souches Hématopoïétiques : de la recherche fondamentale à la recherche clinique / Adoptive Cellular Immunotherapy for the treatment of refractory Adenovirus infections after Hematopoietic Stem Cell Transplantation : From bench to bedside

Qian, Chongsheng 14 June 2017 (has links)
L’allogreffe de cellules souches hématopoïétiques (CSH) est un des seuls traitements curatifs des hémopathies bénignes ou malignes et des déficits immunitaires primitifs. Cependant, les infections notamment virales ainsi que la réaction du greffon contre l’hôte comptent parmi les complications les plus fréquentes des allogreffes associées à une morbidité et une mortalité élevées. Les infections virales surviennent souvent en l’absence de reconstitution immunitaire spécifique dans un contexte d’immunosuppression liée à la GVHD elle-même ou à la prophylaxie ou au traitement de la GVHD. Les traitements médicamenteux anti-viraux préconisés présentent une efficacité inconstante dans ce contexte d’immunodéficience et ne sont pas dénués de toxicité. L’alternative thérapeutique prometteuse est l’immunothérapie adoptive cellulaire notamment celle qui consiste en l’injection de lymphocytes T spécifiques anti-viraux isolés par technique immunomagnétique (VSTs). Cependant, ces lymphocytes T peuvent être la cible des traitements immunosuppresseurs administrés pour la GVHD mais également par eux-mêmes être potentiellement la cause de la survenue ou de la réactivation d’une GVHD. Nous avons montré dans ce travail que l’efficacité des VSTs, qui repose sur leur expansion in vivo lors de la rencontre avec le virus circulant, est principalement permise par les sous-populations lymphocytaires les plus immatures, même si elles ne sont présentes qu’en faible proportion. Nous défendons dans ce travail le fait que l’efficacité des VST ainsi que leur persistance repose prioritairement sur la présence des sous-populations lymphocytaires T les plus immatures et ce quel que soit le degré de compatibilité HLA entre les VSTs et le receveur. De plus, leur sensibilité modérée aux corticoïdes, que nous avons étudiée in vitro, ne justifie pas la modulation de l’immunosuppression lors de l’injection des ADV-VSTs, comme observé in vivo dans le protocole clinique multicentrique de phase I/II que nous avons mené entre 2012 et 2015. En effet, ce protocole clinique ne rapporte aucune GVHD de novo après injection d’ADV-VSTs ; en revanche, la modulation de l’immunosuppression peut potentiellement être incriminée dans la réactivation de GVHD dans les semaines suivant l’injection des ADV-VSTs. La réalisation d’un essai comparatif de phase II permettra de prouver très clairement le rôle des VSTs dans la réactivation de GVHD. / Hematopoietic stem cell transplantation (HSCT) is one of the only curative treatments for benign or malignant hematological diseases and primary immune deficiencies. However, viral infections and graft-versus-host disease (GVHD) are among the most frequent complications after HSCT associated with high morbidity and mortality. Viral infections often occur in the absence of specific immune reconstitution in the context of immunosuppression related to GVHD itself or to the prophylaxis or treatment of GVHD. The recommended anti-viral drug treatments have an inconsistent efficacy in this context of immunodeficiency and are not devoid of toxicity. The promising therapeutic alternative is adoptive immunotherapy, in particular the infusion of specific anti-viral T lymphocytes isolated by immunomagnetic technique (VSTs). However, these T lymphocytes may be targeted by immunosuppressive treatments administered for GVHD, but also may be the cause of the onset or reactivation of GVHD. We have shown in this work that the efficacy of VSTs, which is based on their in vivo expansion when they encounter the circulating virus, is mainly allowed by the most immature lymphocyte subpopulations, even in a small proportion. We argue in this work that the efficacy of VSTs and their persistence is mainly based on the presence of the most immature T lymphocyte subpopulations and this regardless of the degree of HLA compatibility between the VSTs and the recipient. Moreover, their moderate sensitivity to corticosteroids, which we have studied in vitro, does not justify the modulation of immunosuppression at the time of infusion of ADV-VSTs, as observed in vivo in the multicenter phase I / II clinical trial we conducted between 2012 and 2015. Indeed, this clinical trial does not report any de novo GVHD after ADV-VSTs infusion. On the other hand, modulation of immunosuppression may potentially be incriminated in the reactivation of GVHD within weeks of ADV-VST infusion. A Phase II comparative trial will bring the evidence of efficacy and will clearly determine the role of VSTs in the reactivation of GVHD
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Medidas utilizadas na prevenção de infecções em transplante de células-tronco hematopoéticas: evidências para a prática / Infection prevention measures used in hematopoietic stem cell transplantation: evidences for practice

Garbin, Livia Maria 30 June 2010 (has links)
O transplante de células-tronco hematopoéticas (TCTH) consiste em um procedimento complexo e relacionado à ocorrência de diversas complicações, dentre elas os processos infecciosos decorrentes do longo período de imunossupressão vivenciado após a instituição do regime de condicionamento. Inúmeras medidas têm sido empregadas visando à prevenção e controle de infecções, porém, observam-se divergências em relação à utilização das mesmas; sendo que o emprego da prática baseada em evidências possibilita ao profissional tomar decisões em relação à sua prática fundamentadas em resultados de pesquisas científicas atuais. Esta revisão integrativa da literatura teve como objetivo identificar e avaliar as evidências disponíveis na literatura e publicadas nos últimos 20 anos em relação ao uso de três medidas de prevenção de infecção em pacientes submetidos ao TCTH durante o período de internação: uso de filtros de ar de alta eficiência, isolamento protetor e máscaras. Para a seleção dos artigos foram utilizadas as bases de dados LILACS, PUBMED, CINAHL, EMBASE e a Biblioteca Cochrane. A amostra foi composta por 15 estudos, sendo que apenas um apresentou nível de evidência forte (nível I), dois apresentaram nível de evidência moderado (nível IV e V) e doze consistiram em estudos com evidências fracas (nível VI e VII). Dez estudos abordaram a utilização dos filtros HEPA, sendo recomendado seu emprego para pacientes submetidos ao transplante alogênico durante o período de neutropenia. A necessidade de seu uso para pacientes submetidos ao transplante autólogo ainda é controversa. Nove trabalhos abordaram o uso do isolamento protetor e, embora alguns autores relatem que o emprego do mesmo parece apresentar benefícios quando não se dispõe de filtros HEPA, a utilização desta medida já não é mais indicada tanto pelos Centers for Disease Control and Prevention (CDC) quanto pela maioria dos estudos analisados. Em relação à utilização de máscaras por pacientes, profissionais de saúde ou visitantes dentro das unidades de internação para TCTH, não foram encontrados estudos com evidências fortes que justifiquem o seu uso. No entanto, recomenda-se que sejam seguidas as diretrizes dos CDC quanto ao uso de respiradores especiais (como as máscaras N95) pelos pacientes imunocomprometidos submetidos ao TCTH ao deixar a unidade de transplante provida de filtro HEPA quando próximo a ela houver áreas de construção/reforma ou atividades geradoras de poeira. Embora os dados evidenciados auxiliem na tomada de decisão para a implementação da assistência de enfermagem a estes pacientes, verificou-se a necessidade de realização de estudos com nível de evidência forte que comprovem ou refutem a efetividade destas medidas. / Hematopoietic stem cell transplantation (HSCT) is a complex procedure related to the occurrence of different complications, including infectious processes deriving from the long period of immunosuppression experienced after the establishment of the conditioning regimen. Countless measures have been used for infection prevention and control, but divergences are observed with regard to their use; evidence-based practice allows professionals to make decisions for practice based on current scientific research results. This integrative literature review aimed to identify and assess evidence available in literature and published in the last 20 years about the use of three infection prevention measures in patients submitted to HSCT during hospitalization: use of high-efficiency air filters, protective isolation and masks. LILACS, PUBMED, CINAHL, EMBASE and the Cochrane Library were used to select the articles. The sample comprised 15 studies, only one of which presented strong evidence (level I), while two presented moderate evidence (levels IV and V) and twelve were studies with weak evidence (levels VI and VII). Ten studies discussed the use of HEPA filters, recommended for patients submitted to allogeneic transplantation during the neutropenia period. It remains controversial whether these filters need to be used for patients submitted to autologous transplant. Nine studies addressed the use of protective isolation and, although some authors report that using this measure can be beneficial when HEPA filters are unavailable, neither the Centers for Disease Control and Prevention (CDC) nor by most of the studies under analysis indicate it any longer. With regard to the use of masks by patients, health professionals or visitors inside HSCT hospitalization units, no studies with strong evidence were found that justify its use. However, it is recommended that CDC recommendations be followed regarding the use of special respirators (like N95 masks) by immunocompromised patients submitted to HSCT when they leave the transplantation unit with a HEPA filter in case of nearby construction/reform areas or activities that generate dust. Although the evidenced data support decision making with a view to nursing care delivery to these patients, research with strong evidence is needed to prove or reject the efficacy of these measures.
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Alterações bucais em pacientes submetidos ao transplante de células tronco hematopoiéticas: estudo longitudinal / Oral complications in patients undergoing hematopoietic stem cell transplantation: a longitudinal study

Ana Cláudia Luiz 03 May 2012 (has links)
A boca é local de frequentes complicações relacionadas ao transplante de células tronco hematopoiéticas (TCTH) tais como xerostomia, disgeusia, disfagia, mucosite, infecções oportunistas e doença do enxerto contra hospedeiro (DECH). Sabe-se que estas complicações podem comprometer a qualidade de vida do paciente e interferir na morbidade pós-TCTH. O dentista é o profissional da saúde que deverá intervir no momento correto para tratar e minimizar esses efeitos secundários do TCTH. Para tanto é importante conhecermos o momento em que cada complicação ocorre para que a intervenção seja pronta e eficiente. O objetivo principal deste estudo foi identificar e quantificar as alterações bucais em indivíduos submetidos ao TCTH em cinco momentos consecutivos desde antes do início do condicionamento pré-TCTH até o dia 100 pós-TCTH. Como objetivos secundários buscamos investigar possíveis relações entre a severidade da mucosite oral e a manifestação da DECH com dados demograficos (sexo, idade), com o status de saude bucal (por meio dos índices IHO-S, CPOD, número de dentes cariados) e com a realização de adequação bucal pré-TCTH, e ainda, somente para a DECH, também foi investigada a possível relação entre esta doença com infecção sistêmica por citomegalovírus e com a manifestação de mucosite oral severa. Foram incluídos no estudo 27 indivíduos com doenças hematológicas do Serviço de Transplante de Medula Óssea do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP), com idade 12 anos que receberam TCTH alogênico. Os indivíduos foram examinados em cinco momentos consecutivos. No primeiro momento, pré-TCTH, foi realizada a coleta de índices de saúde bucal e aplicação de questionário sobre o histórico de tratamentos odontológico prévios. Nos momentos de 10, 20, 60 e 100 dias pós-TCTH foram avaliadas as manifestações bucais presentes. A incidência de mucosite oral foi de 82,6% considerando todos os momentos avaliados. Mucosite oral severa, ou seja, graus 3 e 4 (OMS) foi observada em 57,9% dos pacientes avaliados nos momentos 2 e 3. Dez (37%) pacientes apresentaram GVHD em algum órgão, e destes, 8 (80%) apresentaram GVHD de boca. Infecção sistêmica por CMV foi diagnosticada em 6 (22,2%) pacientes. Concluímos que entre as queixas levantadas, dor bucal e disfagia foram as mais referidas. O período de maior incidência das complicações bucais foi nos segundo e terceiro momentos, ou seja, D+10 e D+20, representando deste forma, o período de maior morbidade do tratamento. Não houve associação entre a severidade de mucosite oral e idade, sexo, fonte de células, regime de condicionamento, número de dentes cariados, IHO-S, CPOD e preparo bucal pré-TCTH. Para a DECH a única relação encontrada foi para fonte de células, tendo sido observada menor chance de ocorrer DECH quando a fonte de células foi o sangue periférico. / The mouth is a well-known site of complications of the hematopoietic stem cell transplantation (HSCT) such as dry mouth, dysgeusia, dysphagia, mucositis, opportunistic infections and graft versus host disease (GVDH). It is known that these complications can compromise the patients quality of life and morbidity post-HSCT. The dentist is the health professional who should interfere at the right time to treat and minimize these side effects of HSCT. Thus, it is important to know the time at which each complication occurs to be dynamic and efficient. The main objective of this study was to identify and quantify the oral complications in patients treated with HSCT in five consecutive moments starting before conditioning chemotherapy until day 100 post-HSTC. As secondary objectives we seek to investigate possible relationships between the severity of oral mucositis and the manifestation of GVHD with demographic data (gender, age), with the oral health status (IHO-S, CPOD, number of decayed teeth) and dental treatment previously HSCT, and, only for GVHD, was also investigated the possible relationship between this disease with systemic cytomegalovirus infection and the manifestation of severe oral mucositis. It was included in the study 27 patients with hematologic diseases who were admitted in the Unit of Bone Marrow Transplantation, Hospital of Clinics, Faculty of Medicine, University of Sao Paulo (HC-FMUSP), 12 years old whom received allogeneic HSCT. The subjects were examined in five consecutive moments. At the first moment, before HSCT, the oral health índex evaluation and a questionnaire about history of previous dental treatments were performed. Besides that, 10, 20, 60 and 100 days after HSCT they were evaluated for oral manifestations. Oral mucositis incidence was 82,6% and 57,9% of these patients presented severe mucositis. Ten (37%) patients had GVHD in any organ, and of these, 8 (80%) had oral GVHD. Infection by CMV was diagnosed in 6 (22.2%) patients. We conclude that among the complaints raised, mouth pain and dysphagia were the most mentioned. The period of increased incidence of oral complications was the second and third times (D +10 and +20), representing the increased morbidity period. There was no association between the severity of oral mucositis and age, sex, cell source, conditioning regimen, number of decayed teeth, IHO-S, CPOD and dental treatment pre-HSCT. For GVHD the only relation found was with source of cells, in which, GVHD was less likely to occur when the source of cells was peripheral blood.

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