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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.
11

G-CSF in Healthy Allogeneic Stem Cell Donors

Hölig, Kristina 05 August 2020 (has links)
Mobilization of peripheral blood stem cells (PBSC) in healthy volunteers with granulocyte colony-stimulating factor (G-CSF) is currently carried out at many institutions worldwide. This report presents the experience of the Dresden center regarding donor evaluation and mobilization schedule. Data regarding efficacy, short- and long-term safety of G-CSF treatment gained from 8290 PBSC collections in healthy donors are outlined. These results are discussed against the background of the available evidence from the literature. Although established as a standard procedure, G-CSF application to allogeneic donors will always be a very delicate procedure and requires the utmost commitment of all staff involved to ensure maximum donor safety. (PBSC) donation does not require hospitalization and is generally assumed to be less physically demanding for the donor. However, application of mobilizing agents is stringently required for successful HSC mobilization. The standard substance, which is almost exclusively used in healthy donors worldwide, is recombinant human granulocyte colony-stimulating factor (rhG-CSF). Two preparations – filgrastim and lenograstim – are available and have been approved for PBSC mobilization for about 15 years in Germany. Currently, more than 20,000 healthy donors worldwide receive rhG-CSF for PBSC mobilization every year [7]. At the Dresden University Hospital, PBSC collections have been performed since 1996. In the two collection facilities associated with the university hospital, 8,290 allogeneic PBSC collections from 8,005 donors (i.e. 285 second collections) have been documented in a database up until May 2012. This paper presents the data of our own group, and summarizes the current knowledge regarding the short- and long-term effects of G-CSF treatment in healthy stem cell donors.
12

Papel de Notch e NF-kB na regulação de fatores de transcrição durante a diferenciação in vitro de células T a partir de células progenitoras hematopoéticas CD34+ / Role of Notch and NF-kB in the regulation of transcription factors during in vitro differentiation of T cells from CD34+

Schiavinato, Josiane Lilian dos Santos 01 April 2011 (has links)
Em estudos anteriores desenvolvidos por este grupo de pesquisa uma expressão mais elevada de alvos transcricionais e componentes da via NF-kB, bem como altos níveis de NOTCH1, foi identificada em células-tronco hematopoéticas (CTH) CD34+ de sangue de cordão umbilical (SCU) quando comparadas às CTH CD34+ de medula óssea (MO). Este grupo verificou ainda, por comparação das células CD34+ com as CD133+ (mais primitivas) que diversos fatores de transcrição (FT) envolvidos com o potencial de hemangioblasto, com a autorenovação das CTH, e com a diferenciação linfóide; como: RUNX1/AML1, GATA3, USF1, TAL1/SCL, HOXA9 e HOXB4 apresentaram-se mais expressos em células mais primitivas. A potencial participação das vias Notch e NF-kB na regulação destes FT tem importância conceitual e prática no entendimento da biologia das CTH, e dos processos envolvidos na diferenciação destas células. Com isto em vista, este projeto teve como objetivo, estudar o papel da via NF-kB e da via Notch na regulação destes FT. Para isso, um modelo experimental in vitro, de diferenciação de CTH CD34+ em linfócitos T, foi utilizado e a influência de fatores agonistas e inibidores farmacológicos destas vias, foram avaliados por citometria de fluxo e PCR em tempo real. Nossos resultados evidenciam o papel da via Notch na regulação transcricional de HOXB4 e GATA3 em células-tronco hematopoéticas CD34+ humanas, o que foi confirmado com base na expressão dos alvos diretos de Notch (HEY1 e HES1). Notamos ainda, que a expressão dos transcritos HES1, GATA3 e HOXB4 é prejudicada pela síntese protéica das CTH, uma vez que quando empregamos o prétratamento com a droga CHX há aumento da transcrição dos mesmos. Também podemos inferir que a ação do TNF- é positiva sobre esses transcritos, já que quando o utilizamos há elevação do nível de expressão desses transcritos, com exceção a HES1. Em relação ao cocultivo das CTH com as células estromais de camundongos, verificamos que apenas a linhagem OP9-DL1 detém a capacidade de promover a diferenciação celular T, e isso foi comprovado pelo surgimento de células comprometidas com a linhagem linfocítica T, através da presença dos marcadores de superfície específico CD7+ e CD1a+. Esses resultados auxiliarão na compreensão dos mecanismos moleculares de regulação transcricional envolvidos não apenas na diferenciação de linfócitos T, mas também na manutenção de um estado mais primitivo das CTH. Este conhecimento pode vir a contribuir com o desenvolvimento ou otimização de protocolos laboratoriais visando à expansão de CTH ou geração de células T para usos terapêuticos. / In previous studies by this research group a higher expression of transcriptional targets and components via NF-kB, as well as high levels of NOTCH1, was identified in hematopoietic stem cells (HSC) CD34 + cells from umbilical cord blood (UCB) compared to CD34 + hematopoietic stem cells from bone marrow (BM). This group also found, by comparing the CD34 + cells with CD133 + (more primitive) that several transcription factors (TF) involved in the potential of hemangioblast, with self-renewal of hematopoietic stem cells and to differentiated lymphocytic; as Runx1 / AML1, GATA3, USF1, TAL1/SCL, HOXB4 and HOXA9 were more expressed in more primitive cells. The potential involvement of Notch signaling pathways and NF-kB in the regulation of FT has conceptual and practical importance in understanding the biology of HSC, and the processes involved in differentiation of these cells. With this in mind, this project aimed to study the role of NF-kB pathway and Notch signaling in the regulation of FT. For this, an experimental model in vitro differentiation of CD34 + hematopoietic stem cells into T lymphocytes, was used and the influence of pharmacological agonists and inhibitors of these pathways were evaluated by flow cytometry and real-time PCR. Our results highlight the role of Notch signaling in the transcriptional regulation of GATA3 and HOXB4 in hematopoietic stem cells CD34 + human, which was confirmed based on the expression of direct targets of Notch (HES1 and HEY1). We also note that the expression of transcripts HES1, GATA3 and HOXB4 protein synthesis is hampered by the HSC, since when we use the pre-treatment with the drug there CHX increased transcription thereof. We can also infer that the action of TNF- is positive about these transcripts, since when we use it for raising the level of expression of these transcripts, except the HES1. In relation to the HSC coculture with stromal cells of mice, we found that only the line-DL1 Op9 has the ability to promote T cell differentiation, and this was evidenced by the appearance of cells committed to the T lymphocyte lineage, through the presence of specific surface markers CD7 + and CD1a +. These results will help understand the molecular mechanisms of transcriptional regulation involved not only in the differentiation of T lymphocytes, but also in maintaining a more primitive state of HSC. This knowledge may contribute to the development or optimization of laboratory protocols aimed at the expansion of HSC or generation of T cells for therapeutic use.
13

Pupečníková krev - vliv kryokonzervace a demografických údajů matky a dítěte na jejím přihojení při transplantaci / Cord blood - influence of cryopreservation and demographic data of mother and child on engraftment for the transplantation

SKLADANÁ, Veronika January 2011 (has links)
The Master´s thesis gives an overview of cord blood, its use, processing and cryopreservation. The role of cord blood as an alternative resource for transplantation is being widely discussed. In the experimental part, 50 grafts of donor cord blood were processed and the effect of cryopreservation and demographic factors of mother and child were evaluated on the cellularity of cord blood. Based on the evaluation, a recommendation about the inclusion of additional tests in routine processing of cord blood were made.
14

Papel de Notch e NF-kB na regulação de fatores de transcrição durante a diferenciação in vitro de células T a partir de células progenitoras hematopoéticas CD34+ / Role of Notch and NF-kB in the regulation of transcription factors during in vitro differentiation of T cells from CD34+

Josiane Lilian dos Santos Schiavinato 01 April 2011 (has links)
Em estudos anteriores desenvolvidos por este grupo de pesquisa uma expressão mais elevada de alvos transcricionais e componentes da via NF-kB, bem como altos níveis de NOTCH1, foi identificada em células-tronco hematopoéticas (CTH) CD34+ de sangue de cordão umbilical (SCU) quando comparadas às CTH CD34+ de medula óssea (MO). Este grupo verificou ainda, por comparação das células CD34+ com as CD133+ (mais primitivas) que diversos fatores de transcrição (FT) envolvidos com o potencial de hemangioblasto, com a autorenovação das CTH, e com a diferenciação linfóide; como: RUNX1/AML1, GATA3, USF1, TAL1/SCL, HOXA9 e HOXB4 apresentaram-se mais expressos em células mais primitivas. A potencial participação das vias Notch e NF-kB na regulação destes FT tem importância conceitual e prática no entendimento da biologia das CTH, e dos processos envolvidos na diferenciação destas células. Com isto em vista, este projeto teve como objetivo, estudar o papel da via NF-kB e da via Notch na regulação destes FT. Para isso, um modelo experimental in vitro, de diferenciação de CTH CD34+ em linfócitos T, foi utilizado e a influência de fatores agonistas e inibidores farmacológicos destas vias, foram avaliados por citometria de fluxo e PCR em tempo real. Nossos resultados evidenciam o papel da via Notch na regulação transcricional de HOXB4 e GATA3 em células-tronco hematopoéticas CD34+ humanas, o que foi confirmado com base na expressão dos alvos diretos de Notch (HEY1 e HES1). Notamos ainda, que a expressão dos transcritos HES1, GATA3 e HOXB4 é prejudicada pela síntese protéica das CTH, uma vez que quando empregamos o prétratamento com a droga CHX há aumento da transcrição dos mesmos. Também podemos inferir que a ação do TNF- é positiva sobre esses transcritos, já que quando o utilizamos há elevação do nível de expressão desses transcritos, com exceção a HES1. Em relação ao cocultivo das CTH com as células estromais de camundongos, verificamos que apenas a linhagem OP9-DL1 detém a capacidade de promover a diferenciação celular T, e isso foi comprovado pelo surgimento de células comprometidas com a linhagem linfocítica T, através da presença dos marcadores de superfície específico CD7+ e CD1a+. Esses resultados auxiliarão na compreensão dos mecanismos moleculares de regulação transcricional envolvidos não apenas na diferenciação de linfócitos T, mas também na manutenção de um estado mais primitivo das CTH. Este conhecimento pode vir a contribuir com o desenvolvimento ou otimização de protocolos laboratoriais visando à expansão de CTH ou geração de células T para usos terapêuticos. / In previous studies by this research group a higher expression of transcriptional targets and components via NF-kB, as well as high levels of NOTCH1, was identified in hematopoietic stem cells (HSC) CD34 + cells from umbilical cord blood (UCB) compared to CD34 + hematopoietic stem cells from bone marrow (BM). This group also found, by comparing the CD34 + cells with CD133 + (more primitive) that several transcription factors (TF) involved in the potential of hemangioblast, with self-renewal of hematopoietic stem cells and to differentiated lymphocytic; as Runx1 / AML1, GATA3, USF1, TAL1/SCL, HOXB4 and HOXA9 were more expressed in more primitive cells. The potential involvement of Notch signaling pathways and NF-kB in the regulation of FT has conceptual and practical importance in understanding the biology of HSC, and the processes involved in differentiation of these cells. With this in mind, this project aimed to study the role of NF-kB pathway and Notch signaling in the regulation of FT. For this, an experimental model in vitro differentiation of CD34 + hematopoietic stem cells into T lymphocytes, was used and the influence of pharmacological agonists and inhibitors of these pathways were evaluated by flow cytometry and real-time PCR. Our results highlight the role of Notch signaling in the transcriptional regulation of GATA3 and HOXB4 in hematopoietic stem cells CD34 + human, which was confirmed based on the expression of direct targets of Notch (HES1 and HEY1). We also note that the expression of transcripts HES1, GATA3 and HOXB4 protein synthesis is hampered by the HSC, since when we use the pre-treatment with the drug there CHX increased transcription thereof. We can also infer that the action of TNF- is positive about these transcripts, since when we use it for raising the level of expression of these transcripts, except the HES1. In relation to the HSC coculture with stromal cells of mice, we found that only the line-DL1 Op9 has the ability to promote T cell differentiation, and this was evidenced by the appearance of cells committed to the T lymphocyte lineage, through the presence of specific surface markers CD7 + and CD1a +. These results will help understand the molecular mechanisms of transcriptional regulation involved not only in the differentiation of T lymphocytes, but also in maintaining a more primitive state of HSC. This knowledge may contribute to the development or optimization of laboratory protocols aimed at the expansion of HSC or generation of T cells for therapeutic use.
15

Characterization of the UM171-Graft: Dissecting the lymphoid lineage potential of the UM171-Graft

Maalaoui, Hana 04 1900 (has links)
De nos jours, la greffe de cellules souches hématopoïétiques (GCSH) de type allogénique est le traitement standard pour de nombreuses hémopathies malignes, et ce, en dépit des taux élevés de complications liées à la transplantation, telles que les infections, les rechutes et la maladie du greffon contre l’hôte (GVH), associées à cette procédure. Depuis les deux dernières décennies, plusieurs stratégies visant à contrôler la maladie du GVH ont émergé et incluent la déplétion partielle et la manipulation ex vivo des cellules T du greffon. En revanche, ces stratégies peuvent entrainer de sévères déficits immunitaires post-greffe. En comparaison avec les autres sources de cellules souches, une faible incidence de la maladie du GVH et de rechute est observée chez les patients recevant une greffe de sang de cordon ombilical (SC). En contrepartie, ce type de greffe engendre des retards dans la restauration immunitaire, rendant ainsi les patients plus susceptibles aux agents pathogènes. À l’inverse, une augmentation plus importante de la production de cellules T naïves, d’émigrants thymiques récents et de l’abondance des clonotypes des cellules T fut détectée chez les patients ayant reçu une GCSH dérivée du sang d’un seul cordon traité avec UM171, une molécule utilisée pour l'amplification ex vivo des CSHs dérivés de SC, relativement aux patients ayant reçu une GCSH standard. Dans ce mémoire, nous essaierons de comprendre le mécanisme moléculaire sous-jacent à la restauration immunitaire chez les patients transplantés avec un greffon de SC traité avec UM171, nous tenterons de déceler des progéniteurs lymphoïdes au sein des cellules de SC traitées avec UM171 et nous essaierons d’identifier un marqueur de surface qui pourrait être utilisé pour enrichir les progéniteurs lymphoïdes. Nos résultats démontrent la présence de deux "clusters" lymphoïdes, PCL et LMPP, qui expriment potentiellement CD10, et sont plus nombreux dans les échantillons de SC CD34+ traités avec UM171 comparativement aux contrôles. En utilisant les marqueurs de surface CD10 et CD45RA, nous avons pu identifier deux populations CD34+ (CD10medCD45RAmed/lo et CD10hiCD45RAhi) qui sont multipliées dans les cultures traitées avec UM171 relativement aux contrôles. En outre, nous démontrons également que seules les cellules CD45RA- peuvent générer les deux populations CD10+ in vitro, ce qui suggère que les cellules CD10medCD45RAmed/lo définissent une population plus primitive que les cellules CD10hiCD45RAhi. De surcroit, nous proposons que la population CD10medCD45RAmed/lo pourrait contenir des LMPPs qui se différencieront en PCLs inclus dans la population CD10hiCD45RAhi. D'un point de vue fonctionnel, nous observons un développement et une maturation des lymphocytes T nettement plus rapide pour la population CD10+CD34+ relativement à la population CD34+ totale à 3 et 6 semaines, ce qui suggère que CD10 pourrait être utilisé comme marqueur de progéniteurs lymphoïdes. Par ailleurs, nous détectons également un pourcentage plus élevé de cellules ayant un phénotype ILC dans la population CD10+CD34+ comparativement à la population CD34+ totale, ce qui suggère que la population CD10+CD34+ peut potentiellement contenir des progéniteurs lymphoïdes capables de produire différents types de cellules immunitaires. D’autre part, la population CD45RA+ produit plus rapidement des lymphocytes T contrairement à la population CD45RA-. En conséquence, nous proposons que la population CD45RA- contient des cellules primitives (ex. CSH) qui à leur tour génèrent des progéniteurs multipotents contenus dans la population CD10+CD34+ (ex. LMPP) et qui éventuellement produiront des progéniteurs à potentiel plus restreint inclus dans la population CD45RA+ (ex. CLP). En somme, ce mémoire identifie pour la première fois une population CD10+CD34+ présente dans le greffon traité avec UM171 avec un potentiel T et produisant potentiellement des ILCs. L’un des problèmes majeurs liés à la GCSH dérivée du SC est une restauration immunitaire retardée; par conséquent, optimiser l’infusion de cellules CD34- en augmentant le nombre de progéniteurs lymphoïdes pourrait considérablement aider à stimuler la restauration immunitaire chez les patients recevant une GCSH dérivée de SC. / Currently, allogeneic hematopoietic stem cell transplantation is a standard treatment for many hematological malignancies, although high rates of transplant-related complications such as infections, relapse, and GVHD has constrained the implementation of HSCT. Strategies have emerged to manage GVHD and include partial T-cell depletion and ex vivo manipulation of donor T cells, albeit they have adverse effects on post-transplantation immune recovery and can cause profound immunodeficiency. In comparison to other stem cell sources, a lower incidence of chronic GVHD and relapse is reported in patient receiving cord blood (CB) transplant, although they also display an enhanced susceptibility to pathogens caused by an ineffective T-cell reconstitution. In contrast, we reported a greater increase in naïve T cells production, recent thymic emigrants and T cell clonotype from 3 months to 6 and 12 months in patient transplanted with a single CB graft expanded with UM171, a small molecule used for the ex vivo expansion of CB HSCs, as compared to counterpart patients receiving unmanipulated CB graft. In this master research, we aimed to understand the molecular mechanism underlying T-cell reconstitution in patients transplanted with UM171- expanded CB graft. We tried to identify lymphoid progenitors within the highly heterogeneous CD34+ CB cells treated with UM171 using Cite-Seq, find a surface marker that can be used to enrich for early lymphoid progenitors using flow cytometry, and assess their lineage potential using artificial thymic organoids. Our results highlight the presence of two lymphoid clusters, CLP and LMPP, expressing CD10. The LMPP cluster is about 6 fold expanded in UM171-treated cells as compared to uncultured and DMSO-treated cells. Using the marker CD10 and CD45RA we identify two CD34+ populations (CD10medCD45RAmed/lo and CD10hiCD45RAhi) that are significantly expanded in CD34+ CB cells cultured in the presence of UM171 in contrast to uncultured CD34+ CB cells and DMSO-supplemented cultures. Furthermore, we demonstrate that only the CD45RA-negative cells can give rise to both CD10-positive subsets in vitro, suggesting that CD10medCD45RAmed/lo cells define a subset with a more primitive phenotype than CD10hiCD45RAhi. We propose that the CD10medCD45RAmed/lo subset could contain LMPPs that will commit to CLPs contained within the CD10hiCD45RAhi subset. Functionally, we compared T-cell development and maturation of the CD10+CD34+ subset (including CD10medCD45RAmed/lo and CD10hiCD45RAhi) to the CD45RA+CD34+, CD45RA-CD34+ and total CD34+ subsets and denote a faster T cell development and maturation at 3 and 6 weeks within the CD10-positive subset in contrast to the total CD34+ subset, suggesting that CD10 can be used as a marker of lymphoid precursors in UM171 cultures. We also observe a higher percentage of ILC-like cells within the CD10-positive subset as compared to total CD34+ cells suggesting that the CD10- positive subset potentially contains lymphoid precursors with multilineage capacity. Faster T cell development is observed for the CD45RA+ subset whereas CD45RA- cells display the slowest T cell development, hence we propose that the CD45RA- subset contains primitive cells (e.g. HSC) that segregate into lineage-biased multipotent progenitors enriched in the CD10-positive subset (e.g. LMPP) that will give rise to lineage-restricted precursors that are CD45RA+ (e.g. CLP). In sum, our findings represent the first identification of a CD10-positive population within the UM171- expanded graft that has T potential and could potentially produce ILCs. Delayed immune reconstitution is a major obstacle impeding the implementation of CB HSCT; therefore optimizing infusion of CD3+ donor cells by enriching for lymphoid precursors could help boost T-cell reconstitution following allogeneic HSCT.

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