The engraftment of haemopoietic stem/progenitor cells (HSPCs) from umbilical cord blood (UCB) into adult recipients, although advantageous in terms of sourcing units, the decreased need to match donor and recipient and reduced risk of graft versus host disease (GvHD), is delayed compared to grafts using HSPCs from mobilised peripheral blood (MPB) or bone marrow (BM). One reason for this is the limited number of HSPCs (CD34+/CD133+ cells) in a unit of UCB compared to MPB or BM. The CXCR4-CXCL12 axis is widely recognised as a key player in the bone marrow homing, retention, and engraftment of HSPCs. The aim of this thesis was to investigate whether the engraftment of HSPCs from UCB into the bone marrow could be improved. Firstly, a novel in vitro 3D time-lapse chemotaxis assay to assess the homing capacity of human UCB CD133+ HSPCs, towards the chemokine CXCL12 was developed. One advantage of this assay was that it distinguished cell chemotaxis from chemokinesis and allowed these parameters to be quantified. Human UCB CD133+ HSPC chemotaxis towards CXCL12 was inhibited by the CXCR4 antagonist, AMD3100. Importantly, the presence of CXCL12 or AMD3100 had no affect on cell chemokinesis. To complement the in vitro chemotaxis assay, a short term in vivo homing assay in NSG mice was successfully established. The effect of siRNA silencing of the CXCR4 co-receptor, CD164, which is also expressed on CD133+ HSPCs, on cell migratory and homing ability was investigated. CD164 knock-down using siRNA in human UCB CD133+ HSPCs did not demonstrate an effect on homing to NSG bone marrow in vivo or chemotaxis to CXCL12 in vitro. However, homing to NSG mouse spleen was significantly reduced in cells silenced for CD164. Following this, an 8 day HSPC expansion system using nanofibre scaffolds (Nanex) and differing cytokines was investigated. These serum and feeder free conditions yielded a significant expansion of cells that retained CD133+CD34+ expression and their in vitro chemotactic ability to CXCL12. Time constraints did not permit the engrafting ability of these cells to be analysed in an in vivo HSC reconstitution assay that was initiated. However these studies will provide the basis to support future related research in this laboratory.

La transplantation de sang de cordon ombilical (TSCO) est utilisée pour traiter les enfants atteints de maladies hématologiques en l’absence de donneurs apparentés compatibles. Elle est associée avec des risques plus élevés d’échec de greffe et d’infections opportunistes dans les premiers mois qui suivent la transplantation en comparaison avec une greffe de moelle osseuse. Par contre, la TSCO comporte un risque plus faible de maladie du greffon contre l’hôte et une incidence comparable de rechute de leucémie. Ces quatre complications impliquent directement les lymphocytes T. Dans le but de mieux comprendre le schéma particulier des évènements qui suivent la TSCO et d’améliorer le pronostic des patients, nous avons étudié le potentiel fonctionnel, la persistance et la reconstitution antivirale des lymphocytes T au sein d’un groupe d’enfants transplantés de sang de cordon ombilical (SCO). Étant donné que le SCO contient une majorité de lymphocytes T naïfs, nous avons étudié les lymphocytes T spécifiques au HLA-A2:Melan-A26-35 A27L; seul répertoire naïf et abondant caractérisé chez l’homme. Nous avons observé que les lymphocytes T du SCO se différencient en populations effectrices, s’oligoclonalisent, produisent de l’IFN-γ et lysent spécifiquement leur cible suite à la stimulation. Néanmoins, ces cellules produisent moins d’IFN-γ et sont moins bifonctionnelles que leurs homologues issus du sang périphérique d’adultes. Chez les patients, les lymphocytes T du SCO s’épuisent après la TSCO : ils s’oligoclonalisent dramatiquement, sont principalement en différenciation terminale, et une importante fréquence exprime PD-1 (« programmed death-1 ») dans les 3 à 6 premiers mois post-greffe. Très peu de patients sont capables de développer des réponses antivirales durant cette période et la fréquence de lymphocytes T qui expriment PD-1 semble aussi avoir un impact sur le risque subséquent de faire une rechute de leucémie. La deuxième vague de lymphocytes T émergeant à 6 mois post-TSCO mène à une population fonctionnelle et diversifiée. En conclusion, la fonctionnalité des lymphocytes T présents dans les 3 à 6 premiers mois post-TSCO doit être rétablie pour améliorer les risques d’infections opportunistes et de rechute de leucémie. / Umbilical cord blood (UCB) is increasingly used as a source of hematopoietic progenitor cells to treat a variety of disorders in children. UCB transplantation (UCBT) is associated with a reduced incidence of graft-versus-host disease, a robust graft-versus-leukemia effect, more frequent graft failures and a higher incidence of opportunistic infections (OI) compared to bone marrow transplantation; four processes in which donor-derived T lymphocytes are known to be predominantly involved. UCB T cells are mostly naïve. To examine the differential functionality of UCB T cells, CD8+ T cells specific for the melanoma-associated HLA-A2-restricted Melan-A26-35 A27L peptide were isolated from UCB and UCBT recipients, as it represents an abundant preimmune repertoire in human. Following in vitro stimulation, UCB T cells proliferated, oligoclonalized, acquired cell surface markers reflective of effector/memory differentiation, expressed cytolytic activity and produced IFN-γ. While functional properties of UCB T cells resembled their counterparts in adult peripheral blood, they were more likely to reach terminal differentiation following stimulation, produced less IFN-γ and were less frequently bifunctional (IFN-γ and cytolysis). Following UCBT, T cells became exhausted: they oligoclonalized dramatically, exhibited a terminal differentiation phenotype and a high frequency also expressed PD-1 (“ programmed death 1 ”) in the first 3-6 months post-UCBT. Moreover, very few patients developed an antiviral response during this period. Finally, the frequency of PD-1+ CD8+ T cells was significantly higher in subjects who subsequently experienced leukemic relapse. A second wave of T cells emerging at 6 months post-UCBT was observed and characterized by an increase in the repertoire diversity till 1 year, the development of a naïve population with polyfunctional potential and the progressive reconstitution of antiviral responses. This study reports to the biological properties of UCB-derived CD8+ T cells and provides a rationale for the characteristics of UCBT in terms of immune reconstitution and OI. These results also suggest that the first wave of CD8+ T cells in the first 3-6 months post-UCBT should be targeted in priority to improve both OI and leukemic relapse risks.

Résumé : L’obésité est un enjeu de société de première importance; elle est un facteur de risque de plusieurs maladies et engendre d’importantes dépenses en santé. Outre l’alimentation, la sédentarité et les prédispositions génétiques, il semble que l’environnement fœtal soit un facteur déterminant dans le développement de l’obésité. En effet, il a été démontré que les nouveau-nés exposés à un environnement intra-utérin défavorable ont un risque accru de développer, à l’adolescence et à l’âge adulte, l’obésité ainsi que les désordres métaboliques qui y sont associés. Le diabète gestationnel (DG) est l’une des complications de santé maternelle les plus fréquentes et est associé à un risque accru à long terme pour la santé métabolique de l’enfant. Malgré les nombreuses données probantes épidémiologiques concernant le phénomène de la programmation fœtale associée au DG, les mécanismes moléculaires impliqués ont été très peu étudiés. Il est cependant de plus en plus évident que l’épigénétique soit l’un de ces mécanismes. Cette thèse a pour objectif d’identifier les changements de méthylation de l’ADN, la modification épigénétique la plus stable et la plus connue, chez les nouveau-nés exposés in utero au DG. Dans un premier temps, la méthylation de l’ADN de 44 échantillons de placenta et de sang de cordon a été analysée à l’échelle du génome. Cette approche a permis de démontrer que les gènes épigénétiquement modifiés suite à une exposition au DG sont majoritairement retrouvés dans les voies biologiques associées aux maladies métaboliques. Des analyses dans une cohorte indépendante (n=80) ont confirmé l’effet de la glycémie maternelle sur la méthylation de l’ADN des gènes BRD2, LRP1B et CACNA1D impliqués dans la régulation du métabolisme des lipides et du glucose et du système rénine-angiotensine respectivement. Dans un second temps, l’approche par gènes candidats a démontré que l’exposition au DG est associée à la méthylation de l’ADN de gènes du métabolisme des lipides (LPL et ABCA1) du placenta. L’analyse de la méthylation de la LEP et de l’ADIPOQ dans le sang et les tissus adipeux de sujets sévèrement obèses a permis d’identifier des sites de méthylation pouvant potentiellement être utilisés dans le sang comme marqueur de susceptibilité à l’obésité. L’ensemble des résultats de cette thèse démontrent que le DG modifie le profil épigénétique de gènes impliqués dans les voies biologiques des maladies métaboliques (métabolisme énergétique et des lipides) et supportent l’importance de la méthylation de l’ADN dans la programmation de la santé métabolique du nouveau-né ayant été exposé in utero au DG. / Abstract : Obesity has reached epidemic proportions worldwide in both adult and childhood populations and is now recognized as a major public health issue. Obesity is associated with higher incidence of cardiometabolic complications including type 2 diabetes (T2D), dyslipidemia and hypertension as well as with increased health care costs. The fetal environment now appears, with genetics and the environment, as one cause of the obesity epidemic. Indeed, according to the fetal programming hypothesis, newborns exposed to a detrimental fetal environment are more susceptible to develop obesity, T2D and other related chronic disorders when they become teenagers or adults. Many studies have associated gestational diabetes mellitus (GDM) exposure with these long-term metabolic health risks for the newborn. Although, numerous studies show epidemiological evidence to support the fetal programming hypothesis, only a few studies have been undertaken to understand the underlying molecular mechanisms. However, several studies now suggest that epigenetics may be involved. The objective of this thesis is to study changes in DNA methylation, the more stable and studied epigenetic system, in newborns that have been exposed to GDM in utero. First, a genome-wide DNA methylation analysis (BeadChip) was performed in a sample set of 44 placenta and cord blood samples to identify genes and metabolic pathways dysregulated by GDM. This approach showed that genes epigenetically affected by GDM are predominantly involved in metabolic diseases. The associations between maternal glycemia and DNA methylation levels were confirmed, in an independent birth cohort, for BRD2, LRP1B and CACNA1D gene loci involved in the regulation of lipid and glucose metabolism and the renin-angiotensin system respectively. Then, using a candidate gene approach we reported that DNA methylation levels at gene loci involved in lipid metabolism (LPL and ABCA1) are modified in the placenta following exposure to GDM. Furthermore, analyses of LEP and ADIPOQ DNA methylation levels in blood and adipose tissues of severely obese men and women allowed the identification of CpG sites that might be used in blood as a marker of obesity susceptibility. Altogether the results of this thesis show that GDM affects the epigenetic signature of genes involved in metabolic disease pathways (energy and lipid metabolism) and support the role of DNA methylation in metabolic health programming of the newborn exposed to GDM.

Human hematopoietic stem cells (HSCs) are defined by their capacity to self-renew and to differentiate into all blood lineages during an adult lifetime. Based on these unique properties, HSCs are used in transplantation procedures to treat various hematological diseases. However, the low number of HSCs in a graft limits the use of this treatment. To overcome this restrain, different approaches were established to expand HSCs ex vivo; yet, the absence of a reliable surface maker that correlates with HSC activity in culture made the assessment labor-intensive and time-consuming. Using a library of small molecules, we were able to identify pyrimidoindole derivative named UM171 as an agonist for HSC self-renewal. UM171 promotes ex vivo expansion of hematopoietic and stem cell progenitors (HSPC) independently of AhR suppression- a pathway reported by Boitano et al. to have the greatest effect in HSC expansion. Unlike AhR suppression that targets a hematopoietic population with limited proliferative potential, UM171 targets the long-term HSCs. Transcriptome analysis showed that UM171 reduces the levels of transcripts associated with lineage differentiation and induces the expression of genes encoding for membrane proteins, one of the best differentially expressed being the endothelial protein c receptor (EPCR). Cell sorting and transplantation experiments of EPCR expressing cells showed a high correlation with HSC activity. We demonstrated EPCR as a first reliable marker to enrich for HSC in culture and that it is required for HSPC function in vivo. These findings provide a valuable tool for clinical and research applications to optimize further HSPC expansion protocols and understand the molecular machinery that governs the HSC self-renewal. / Le terme de cellules souches hématopoïétiques (CSH) désigne une population rare de cellules capables de générer l’ensemble des lignages hématopoïétiques. Cette définition implique une capacité d’auto-renouvèlement, ainsi qu'un potentiel de prolifération et de différenciation important. La greffe de cellules souches hématopoïétiques est aujourd'hui une modalité thérapeutique pour le traitement de diverses maladies hématologiques et représente pour de nombreux patients un traitement de dernier recours. Malheureusement, le nombre limité de ces cellules dans une unité de sang de cordon est à l’origine du faible taux de réussite des greffes de sang de cordon chez l'adulte. Plusieurs stratégies sont actuellement mises en place pour permettre la multiplication de ces CSH ex vivo. Cependant, Il n’y a jusqu’à ce jour aucun critère ou marqueur phénotypique fiable permettant spécifiquement d'identifier ou d'isoler ces CSH amplifiées, et leur caractérisation reste un défi majeur pour les chercheurs. Dans le laboratoire, nous avons effectué un criblage à haut débit afin de tester le potentiel d’un grand nombre de molécules chimiques à multiplier des cellules souches dérivées de sang de cordon ombilical et nous avons ainsi identifié la molécule UM171, un dérivé pyrimido-indole, qui permet de multiplier par 10 le nombre de CSH et par 100 leur descendance. Nous avons démontré qu' UM171 permet de multiplier les CSH sans affecter la voie de signalisation de la protéine AhR, récemment impliquée dans l'auto-renouvèlement des CSH. L'analyse du transcriptome des CSH exposées à la molécule UM171 a permis d'identifier le récepteur endothélial à la protéine C (EPCR), comme marqueur de surface permettant de prédire le nombre et l'activité des CSH en culture et par conséquent de les isoler et de mieux les caractériser. En combinant des techniques de cytométrie de flux et d'ARN interférents avec des expériences de transplantation à long terme dans des souris immuno-déficientes, nous avons pu démontrer qu' EPCR peut être considéré non seulement comme un premier marqueur fiable pour enrichir les CSH en culture mais aussi qu'il est nécessaire pour la fonction de ces CSH in vivo. Les résultats de ces travaux représentent une avancée majeure pour accélérer les recherches et les applications cliniques sur l'expansion des CSH ex vivo et permettra de comprendre les mécanismes moléculaires qui régissent l'auto-renouvèlement des CSH.

The increasing incidence of children suffering from allergic diseases could be caused by sensitization of immature immune system during the intrauterine development. Several important scientific papers have demonstrated the ability of cord blood cells to respond by elevated proliferation activity after stimulation by common allergens. Following these findings, present study follows the production of cytokines which play a role in the pro- and anti-allergenic tuning of the immune system. Umbilical cord blood cells were stimulated with polyclonal activators (phytohaemagglutinin) and common allergens (ovalbumin, timothy grass, birch, mite). Subsequently, cytokine production was monitored using selected methods that reflect different stages of cell activation - at the level of mRNA by quantitative real time PCR (qRT-PCR), by flow cytometry detection of the presence of intracellular cytokines in different cell subpopulations and by ELISA measurement of cytokines in CBMC culture supernatants. The results obtained point to a very weak ability of these common allergens (timothy grass, birch, mite, ovalbumin) to stimulate CBMC to produce cytokines observed by all of these methodological procedures. Although we did not observe significant differences in CBMC cytokine production (IL-2, IL-4, IL-10, IL-12,...

INTRODUÇÃO: Exposição a fatores ambientais e estresse durante o período intrauterino estão associados com alterações da trajetória do neurodesenvolvimento de forma sexo-dependente. Mecanismos epigenéticos estão envolvidos a esta associação. OBJETIVOS: Analisar de acordo com a exposição ao estresse na gestação o impacto do sexo e de alterações de metilação do DNA no sangue de cordão umbilical nas medidas antropométricas do neonato. MÉTODOS: Foram recrutadas 94 gestantes e aplicados questionários de medidas exposição ao estresse e fatores de risco durante a gravidez. A coleta de sangue do cordão umbilical seguiu protocolo padronizado. Para analisar o estresse foi utilizada análise de componentes principais (ACP) dos fatores de exposição avaliados: status socioeconômico, educação, ganho de peso, índice de massa corporal pré-gravídico, presença de doença psiquiátrica, estresse psicossocial durante a gravidez. Após o ACP fizemos análise de agrupamento por K-means. As análises de metilação foram realizadas utilizando Illumina Infinium Human Methylation450 (450K) BeadChip. Os dados foram analisados pelos pacotes Minfi e ChAMP (Chip Analysis Methylation Pipeline). A partir das posições diferencialmente metiladas (PDMs) foi feito análise de enriquecimento de processos biológicos com a ferramenta WebGestalt. Para avaliar impacto do sexo e alterações de metilação no desfecho antropométrico do neonato usamos modelos de análise linear de regressão múltipla. RESULTADOS: A coorte final para a avaliação do estresse foi composta por 89 pares mãe/recém-nascidos, sendo 50 meninas e 39 meninos. A ACP mostrou que os primeiros 3 componentes explicaram 60% da variabilidade da amostra. Sendo o primeiro componente (CP1) estresse psíquico, o segundo CP estresse social e o CP3 exposição a tóxicos. O biplot dos primeiros dois componentes sugeriu a separação das mães em dois grupos, confirmados pela análise de agrupamentos. Usando o ponto de corte de p-valor < 0,01 e deltabeta-valor>5%, encontramos 110 posições PDMs entre os grupos e restringindo este valor para p-valor < 0,01 e delta beta valor > 10% encontramos 13 PDMs. Usando apenas as crianças adequadas para idade gestacional fizemos análise de metilação diferencial entre os sexos. Foram encontradas 426 PDMs. Nenhuma das 13 PDMs encontradas entre os dois grupos pertenciam ao conjunto das PDMs entre sexos. No modelo de regressão linear multivariada controlando para sexo da criança e idade da mãe não encontramos nenhuma PDM associada aos desfechos antropométricos do neonato. Na análise estratificada por grupos os sítios cg24702040 (MAP3K21), cg21550016 (PAX8) foram estatisticamente significantes para perímetro abdominal e cg18706028 (CCKBR) e cg21550016 (PAX8) foram estatisticamente significantes para índice do perímetro cefálico para a idade. Este estudo sugere que o estresse materno independente do sexo pode afetar o crescimento fetal, mediado por respostas epigenéticas em genes relacionados à resposta ao estresse, regulação negativa da via de sinalização do receptor do fator de crescimento epidérmico, biogênese da sinapse e processo apoptótico / BACKGROUND: Exposure to environmental factors and stress during the intrauterine period are associated with changes in the neurodevelopmental trajectory in a sex-dependent manner. Epigenetic mechanisms are involved in this association. OBJECTIVES: Analyze according to exposure to stress during pregnancy the impact of sex and DNA methylation alterations on umbilical cord blood in the anthropometric measurements of the neonate METHODS: A total of 94 pregnant women were recruited and questionnaires were used to measure stress exposure and risk factors during pregnancy. Umbilical cord blood collection followed a standardized protocol. In order to analyze the stress, the principal components analysis (PCA) of the exposure factors evaluated were: socioeconomic status, education, weight gain, pre-gravid body mass index, presence of psychiatric illness, and psychosocial stress during pregnancy. After the PCA we did group analysis by k-means. Methylation analyzes were performed using Illumina Infinium Human Methylation 450 (450K) BeadChip. The data were analyzed by the Minfi and ChAMP (Chip Analysis Methylation Pipeline) packages. From the differentially methylated positions (DMPs) was made analysis of enrichment of biological processes with the tool WebGestalt. To evaluate gender impact and methylation alterations in the neonatal anthropometric outcome we used multiple regression linear analysis models. RESULTS: The final cohort for the evaluation of stress was composed of 89 mother/newborn pairs, being 50 girls and 39 boys. The PCA showed that the first 3 components accounted for 60% of the variability of the sample. Being the first component (PC1) psychic stress, the second PC social stress and PC3 exposure to toxic. The biplot of the first two components suggested the separation of the mothers into two groups, confirmed by cluster analysis. Using the cutoff point of p-value < 0.01 and delta beta-value > 5%, we found 110 DMPs between the groups and restricting this value to p-value < 0.01 and delta beta-value > 10 % we found 13 DMPs. Using only children suitable for gestational age we did differential methylation analysis between genders. There were 426 DMPs found. None of the 13 DMPs found between the two groups belonged to the pool of DMPs between the sexes. In the multivariate linear regression model controlling for child sex and age of the mother we did not find any DMP associated with the anthropometric outcomes of the neonate. In group-stratified analysis the cg24702040 (MAP3K21), cg21550016 (PAX8) sites were statistically significant for abdominal perimeter and cg18706028 (CCKBR) and cg21550016 (PAX8) were statistically significant for head cephalic circumference for age. This study suggests that maternal stress independent of sex can affect fetal growth, mediated by epigenetic responses in genes related to stress response, negative regulation of the epidermal growth factor receptor signaling pathway, biogenesis of the synapse and apoptotic process

As células-tronco mesenquimais (MSCs) são células estromais não-hematopoiéticas que possuem capacidade de diferenciação, sendo capazes, de diferenciar em diversos tecidos. As MSCs residem em vários tecidos vêm sido isoladas de diferentes tecidos, tais como cartilagem, tendão, tecido adiposo, do vaso e sangue umbilical, além de tecidos fetais . O isolamento e caracterização das populações mesenquimais no modelo ovino se faz importante, visto que ele é usado em ensaios pré-clínicos ortopédicos . Nesse estudo foram utilizados 5 amostras de sangue de cordão umbilical e 5 amostras de tecido adiposo peri-renal, provenientes de 10 ovinos fêmeas adultas. As coletas foram realizadas através de cirurgia para que o material coletado fosse o mais asséptico possível. Essas amostras foram submetidas a diferentes protocolos de isolamento, com a finalidade de se testar o mais eficiente. Somente um protocolo de cada tecido mostrou-se eficiente no isolamento da MSCs, porém nenhuma dessas amostras manteve-se viável após a primeira passagem. / Mesenchymal stem cells (MSCs) are non hematopoietic stromal cells that are able to differentiate through several tissues . MCSs home in several tissues and are being isolated from different tissues, such cartilage, tendon, adipose tissue, vessels and umbilical blood, and also from fetal tissues . The isolation and characterization of mesenchymal cells in sheep are important, because it is used in orthopedic pre-clinical trials . In this study were used 5 samples of umbilical blood and 5 samples of perirenal adipose tissue from 10 female sheep. All the samples were obtained through surgery, to harvest aseptic samples. These samples were tested in different protocols to evaluate the more efficient. Just one protocol from each source showed significant results in isolation, although none of the samples survived trough the first passage.

A coleta de sangue de cordão umbilical e placentário (SCUP) é uma atividade delegada ao enfermeiro, abrindo um novo campo de atuação para esse profissional que se configura em um novo processo de trabalho e na inserção de mais um procedimento no contexto da assistência obstétrica. O objetivo deste estudo foi compreender a vivência de enfermeiras no exercício da atividade de coleta de amostras de SCUP para armazenamento de células progenitoras hematopoiéticas. Trata-se de um estudo descritivo com abordagem metodológica qualitativa. Os referenciais teórico e metodológico adotados neste estudo foram o Interacionismo Simbólico e a Teoria Fundamentada nos Dados. Participaram do estudo nove enfermeiras que atuam na atividade de coleta de SCUP para bancos de sangue de privados e públicos. Os dados foram obtidos por meio de entrevistas que foram gravadas e transcritas. A experiência da enfermeira que exerce a atividade de coleta de SCUP é compreendida pelas categorias: ACEITANDO A PROPOSTA DE TRABALHO, TENDO ATRIBUIÇÕES A CUMPRIR, PREPARANDO-SE PARA PROCEDER A COLETA DE SCUP, ENCONTRANDO CONDIÇÕES FAVORÁVEIS PARA REALIZAR A COLETA DE SCUP, UTILIZANDO ESTRATÉGIAS PARA GARANTIR A COLETA DE SCUP, ENCONTRANDO CONDIÇÕES DESFAVORÁVEIS PARA REALIZAR A COLETA DE SCUP, PROCEDENDO À COLETA DE SCUP, CONCLUINDO A COLETA DE SCUP e AVALIANDO O TRABALHO REALIZADO. Trabalhar como um profissional tendo de se inserir em um contexto desconhecido com profissionais que atuam em equipe nas diversas maternidades, coloca a enfermeira coletadora frente a situações que exigem rápida adaptação para que realize a coleta de SCUP, atendendo todas as recomendações exigidas para a coleta desse material. Um dos aspectos evidenciados e merecedor de destaque é o fato da enfermeira coletadora deparar-se com dificuldades referentes ao relacionamento com a equipe que presta assistência obstétrica; esta necessita compreender e incorporar em seu processo de trabalho no contexto da assistência ao parto que a enfermeira coletadora de SCUP presta serviço ao BSCUP público ou privado. Apesar das dificuldades relatadas pelas enfermeiras coletadoras no desenvolvimento de sua atividade, percebe-se que elas se encontram motivadas a continuar atuando nesse novo campo, seja pela remuneração, seja pela percepção de estar realizando uma atividade que beneficiará o tratamento de doenças. Vale ressaltar que este estudo poderá ajudar aos profissionais envolvidos no contexto do parto e nascimento a entenderem a atividade de coleta e a compreenderem que a equipe multiprofissional deve atuar em prol de um objetivo comum, além de serem informados a respeito do potencial que as células-tronco vêm mostrando no tratamento de doenças hematológicas / The umbilical cord blood (UCB) collection is an activity delegated to the nurse, opening a new field of action for this professional who is set on a new process of work and the insertion of a further procedure in the context of obstetrical care. The objective of this study was to understand the experience of nurses in the exercise of the activity of collecting samples of UCB for storage hematopoietic progenitor cells. This is a descriptive study with qualitative approach. The benchmarks theoretical and methodological used in this study were the Interacionism Symbolic and Grounded Theory. Were involved in the study nine nurses who serve in the activity of UCB collection for blood banks, on private and public institutions. The data were obtained through interviews that were recorded and transcribed. The experience of the nurse who carries out the activity of UCB collection is understood by the categories: ACCEPTING THE WORK PROPOSAL, HAVING TASKS TO DELIVER, PREPARING TO PROCEDER THE UCB COLLECTION, FACING FAVOURABLE CONDITIONS TO PROCEDURE THE UCB COLLECTION, USING STRATEGIES TO ASSURE THE UCB COLLECTION, FACING UNFAVOURABLE CONDITIONS TO PROCEDURE THE UCB COLLECTION, DOING THE UCB COLLECTION PROCEDURE, FINALIZING THE UCB COLLECTION PROCEDURE and UNALIZING THE WORK CARRIED. Working as a professional who needs to take part into an unknown context with other professionals who works together in various maternity, puts the nurse through situations that require quick adaptation to develop the UCB collection, attending all the recommendations required for the material collection. One of the aspects highlighted and worthy of note is the fact the nurse encounter themselves with difficulties relating to the relationship with the team that provides obstetrical care, which needs to understand and incorporate in the process of work in the context of assistance for delivery that the nurse provides service to coord bank. Despite the difficulties reported by nurses who develop this activity, is known that they are motivated to continue working in this new field, by the remuneration or by the perception of performing an activity that will benefit the treatment of diseases. This study may help the professionals involved in the obstetrical care to understand the activity of UCB collection and that the multiprofessional team should work towards a common goal, besides being informed about the potential that stem cells come showing in the treatment of hematological diseases

Introdução. As células progenitoras hematopoéticas (CPH) têm sido utilizadas no tratamento de algumas doenças malignas hematológicas e de desordens hematopoéticas. Dentre estas células estão as CPHs provenientes de cordão umbilical e placentário (SCUP). Para coleta e armazenamento destas células foram criados os Bancos de Sangue de Cordão Umbilical e Placentário (BSCUP). No Brasil existe a rede BrasilCord e o BSCUP do Hemocentro de Ribeirão Preto é um dos que compõem esta rede. Objetivo. Avaliar a viabilidade financeira de um banco de sangue de cordão umbilical e placentário público comparando os custos de seus procedimentos com os valores ressarcidos definidos pela tabela SUS. Metodologia: Este estudo utilizou a metodologia de Custeio Baseado em Atividades (Activity-Based Costing - ABC), que procura reduzir as distorções provocadas pelo rateio arbitrário dos custos indiretos utilizando direcionadores de custos. Foram avaliados os custos diretos e indiretos da coleta, transporte, processamento, testagem e criopreservação de CPH proveniente de SCUP no primeiro semestre de 2015. Para os custos indiretos foram definidos os direcionadores de custo. Resultados Os resultados mostram que o BSCUP do Hemocentro de Ribeirão Preto foi deficitário no primeiro semestre de 2015. O déficit apurado por unidade foi de R$1.155,69 para o processamento semiautomatizado e R$1.703,78 para o processamento automatizado. O déficit total no período foi de R$ 100.376,50 quando 50 unidades foram processadas utilizando o método semiautomatizado e 25 pelo método automatizado. Conclusão. O valor ressarcido pelo SUS não cobre os gastos do BSCUP do Hemocentro de Ribeirão Preto. Isso pode ser atribuído a várias causas como: sistemática de pagamento pelo SUS apenas pelo produto criopreservado, elevados índices de rejeição das doadoras na maternidade e de descarte das unidades coletadas, embora este último seja menor que o descrito na literatura, e o custo do armazenamento em longo prazo. Os custos do BSCUP são menores que os descritos na literatura e poderiam ser reduzidos com melhorias de processos de gestão e aumento do número de unidades criopreservadas, bem como, por meio de descentralização de coletas para processamento centralizado. / Introduction. Hematopoietic progenitor cells (HPC) are being used in some hematologic malignancies and hematopoietic disorders treatment. Among these cells are the HPCs from umbilical blood cord (UCB). Umbilical cord blood banks were created to collect and store these cells. In Brazil there is a net called Brasilcord and the umbilical cord blood bank (UCBB)of the Hemocentro de Ribeirão Preto belongs to this net. Objective. To evaluate the financial viability of a public umbilical cord blood bank and compare the costs from its procedure with the values reimbursed defined by the SUS table. Methodology.This study used the ActivityBased Costing, which tries to reduce distortions caused by arbitrary apportionment of indirect costs using cost drivers. Direct and indirect costs of collection, transport, processing, testing and cryopreservation of HPCs from umbilical cord blood were evaluated. Cost drivers were defined for indirect costs. Results. The results showed that there was a deficit in the UCBB of the Hemocentro de Ribeirão Preto in the first semester of 2015. The deficit was R$1.155,69 when the unit was processed by the semi-automated method and R$1.703,78 when it was processed by an automated method. The total deficit in the period was R$100.376,50 as 50 units were processed by a semi-automated method and 25 by an automated method. Conclusion. The amount reimbursed by SUS does not cover the UCBB of Hemocentro de Ribeirão Preto expenses. This can be attributed to several causes such as: systematic of reimbursement used by SUS that only cryopreserved units are payed, high percentage of deferral in the maternity and of discard of collected units, although this latter is smaller than that described in the literature and the cost of storage of the units for long periods. The costs of UCBB are lower than that described in the literature and could be reduced with improvements in managing process and increase the number of cryopreserved units as well as decentralization of collections for centralizes processing.

幹細胞療法是近年的研究熱點之一，然而幹細胞在組織修復中的實際應用受到移植後幹細胞存活率低的制約，約80% 的幹細胞在移植至組織後不能存活。 人類臍帶血管周皮 (HUCPV) 幹細胞為多功能間充質幹細胞移植提供豐富的細胞來源。 在合適的誘導環境下，它們具有向多種間充質細胞系分化的能力。 與從骨髓或臍帶血中提取的間充質幹細胞比較，人類臍帶血管周皮幹細胞的體外增殖更為容易。 在本研究中，我們從人類臍帶血管周圍組織中分離人類臍帶血管周皮幹細胞，並採用流式細胞技術分選細胞表面標記物CD34、CD45呈陰性同時CD44 、CD90、 CD105、 CD146呈陽性的HUCPV細胞。HUCPV細胞在體外培養以及三維支架的環境下具有分化為骨和軟骨的能力。 / 在本研究中，我們主要研究腦和生殖器官表達基因（BRE）在HUCPV細胞中的功能。 BRE蛋白與其他已知蛋白的同源性均不高，目前尚未鑑定出任何功能性的結構域。 至今為止，BRE基因的已知功能大多數是通過對腫瘤模型的研究發現的。 據報導，BRE能夠提高DNA損傷的腫瘤細胞的存活率，但BRE在幹細胞中的作用仍不清楚。 我們發現，當HUCPV細胞分化後，其BRE的表達水平降低。 此外，利用BRE-siRNA降低HUCPV細胞中BRE基因的表達，能夠促進HUCPV細胞向骨和軟骨分化的進程。 因此，我們假設BRE對維持HUCPV細胞的幹細胞功能具有重要的作用。 由於經過BRE基因沉默處理的HUCPV細胞與對照組相比並無顯著的表型差別，我們採用微陣列（microarray）以及比較蛋白組學的方法研究兩者間的區別，從而找出BRE基因的功能以及可能涉及BRE的信號通路。 / 通過微陣列技術，我們深入地分析了BRE基因表達沉默後HUCPV細胞的轉錄組。 在經過BRE基因沉默處理的HUCPV細胞中，我們發現與維持幹細胞多向分化潛能有關的OCT4、 FGF5和FOXO1A等基因的表達顯著下調。 另外，BRE基因的沉默能夠影響表觀遺傳調控基因以及TGF-β 信號通路組成部件的表達，而TGF -β 信號通路是維持幹細胞自我更新的重要通路。 這些結果提示，BRE作為一個重要的調控因子，在維持HUCPV細胞的多向分化潛能的同時能夠防止細胞分化。 / 在比較蛋白組學的研究中，我們發現BRE基因的沉默能夠降低細胞骨架結合蛋白的表達，例如actin, annexin II 及 tropomyosin。 此外，我們利用免疫共沉澱的方法證明了BRE蛋白與actin及 annexin II蛋白直接結合。 細胞骨架的改變可能為HUCPV細胞的分化提供了一個有利的環境，因而BRE基因的沉默能夠促進HUCPV細胞向骨和軟骨分化。 支持這一推論的其中一個依據是Lim et al., 2000; Solursh, 1989; Zhang et al., 2006，文獻報導肌動蛋白多聚化抑製劑能夠促進軟骨形成的過程。 綜上所述，本研究為進一步研究BRE基因在HUCPV細胞中的功能以及與BRE直接作用的蛋白打下了基礎。 / Stem cells therapy has gained considerable attention in recent years. However, the practical use of stem cells for tissue repair has been hindered due to their low survival rate after grafting into tissues, for approximately 80% of the stem cells died after implantation. Human umbilical cord perivascular (HUCPV) stem cells offer a new and rich resource of multipotent mesenchymal stem cells. These cells possess the ability to differentiate into various mesenchymal cell lineages when induced. HUCPV cells can be more easily amplified in culture than mesenchymal stem cells extracted from bone marrow or umbilical cord blood. In this study, HUCPV cells were isolated from the perivascular regions of human umbilical cords. The HUCPV cells were sorted using flow cytometer for CD34⁻, CD44⁺, CD45⁻, CD90⁺, CD105⁺ and CD146⁺ surface markers. These HUCPV cells were found to be capable of differentiating into osteogenic lineage in monolayer culture and chondrogenic lineage in pellet culture. These cells were also found to be capable of differentiating into osteogenic and chondrogenic lineage in silk fibroin which acted as three-dimensional scaffolds for the cells to grow on. / The function of the Brain and Reproductive Organ-Expressed (BRE) gene in the context of HUCPV cells was investigated. The BRE protein shares no homology with any other known gene products and contains no known functional domain. To date, most of what we know about the function of this gene has been conducted in the tumor model. It has been reported that BRE can enhance the cellular survival of cancer cells following DNA damage. The role of BRE in stem cells has never been examined. We have established that BRE expression was down-regulated when HUCPV cells started to differentiate. In addition, silencing BRE expression, using BRE-siRNA, in HUCPV cells could accelerate osteogenic and chondrogenic differentiation. Hence, we hypothesized that BRE played an important role in maintaining the stemness of HUCPV cells. Because there was a lack of phenotypic difference between the BRE-silenced HUCPV cells and cells transfected with the control-siRNA, we decided to profile these cells using microarray and proteomic analyses. The aim was to elucidate the function of the BRE gene and establish whether BRE was involved in any signaling pathways. / In the microarray analysis, we examined the transcriptome of HUCPV cells in response to BRE-silencing in depth. Amongst the genes that we identified were significantly down-regulated by BRE-silencing and involved in the maintenance of pluripotency in ES cells were OCT4, FGF5 and FOXO1A. BRE-silencing also altered the expression of epigenetic genes and also components of the TGF-β signaling pathway. This pathway is crucially involved in maintaining stem cell self-renewal. Therefore, we propose that BRE acts like a modulator that promotes stemness and at the same time inhibits the differentiation of HUCPV cells. / In the comparative proteomic study, BRE-silencing resulted in decreased expression patterns of cytoskeletal binding proteins such as actin, annexin II and tropomyosin. In addition, co-immunoprecipitation experiments revealed that the BRE protein can bind directly with actin and annexin II. It is possible that altering the cytoskeleton may provide a favorable environment for HUCPV cells to differentiate. This may explain why we were able to accelerate osteogenic and chondrogenic differentiation following BRE-silencing. In support of the view, it has been reported that chondrogenesis could be enhanced after cells have been treated with actin polymerization inhibitors (Lim et al., 2000; Solursh, 1989; Zhang et al., 2006). In sum, our studies provide an insight into the function of the BRE gene in HUCPV cells and the proteins that BRE can directly act on. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Chen, Elve. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 135-159). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Thesis/Assessment Committee --- p.i / Abstract --- p.ii / 摘要 --- p.v / Acknowledgements --- p.viii / List of Figures --- p.ix / List of Tables --- p.xiii / Table of Abbreviations --- p.xiv / Contents --- p.xviii / Chapter 1 --- p.1 / Literature Review --- p.1 / Chapter 1.1 --- Stem cells --- p.1 / Chapter 1.2 --- Embryonic stem cells (ESCs) --- p.2 / Chapter 1.3 --- Epiblast-derived stem (EpiS) cells --- p.2 / Chapter 1.4 --- Somatic stem cells (SSCs) --- p.3 / Chapter 1.5 --- Induced pluripotent stem (iPS) cells --- p.5 / Chapter 1.6 --- Human umbilical cord perivascular (HUCPV) cells --- p.7 / Chapter 1.7 --- CD146 --- p.8 / Chapter 1.8 --- Stem cell senescence --- p.9 / Chapter 1.9 --- Brain and reproductive organ-expressed (BRE) protein --- p.12 / Chapter 1.10 --- Stem cell self-renewal --- p.14 / Chapter 1.11 --- Apoptosis --- p.16 / Chapter 1.12 --- Stem cell niche --- p.21 / Chapter 1.13 --- Stem cell homing --- p.22 / Chapter 1.14 --- Objective --- p.22 / Chapter 2 --- p.24 / Accelerated osteogenic and chondrogenic differentiation of HUCPV cells by modulating the expression of BRE --- p.24 / Chapter 2.1 --- Introduction --- p.24 / Chapter 2.2 --- Rationale --- p.27 / Chapter 2.3 --- Materials and Methods --- p.27 / Chapter 2.3.1 --- Extraction of HUCPV cells from umbilical cord --- p.27 / Chapter 2.3.2 --- Cell culture condition --- p.28 / Chapter 2.3.3 --- Flow cytometry analysis and cell sorting --- p.28 / Chapter 2.3.4 --- In vitro osteogenic differentiation --- p.29 / Chapter 2.3.5 --- In vitro chondrogenic differentiation --- p.29 / Chapter 2.3.6 --- Alcian blue staining --- p.29 / Chapter 2.3.7 --- Alizarin red S staining --- p.30 / Chapter 2.3.8 --- Immunofluorescence analysis --- p.30 / Chapter 2.3.9 --- Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) --- p.31 / Chapter 2.3.10 --- Transfection with siRNA --- p.35 / Chapter 2.3.11 --- Microarray --- p.35 / Chapter 2.3.12 --- Cell lysis and immunoprecipitation --- p.36 / Chapter 2.3.13 --- SDS-PAGE and Western blot --- p.36 / Chapter 2.3.14 --- Isoelectric focusing and 2-dimensional gel electrophoresis --- p.37 / Chapter 2.3.15 --- Migration (wound healing) assay --- p.38 / Chapter 2.4 --- Results --- p.38 / Chapter 2.4.1 --- HUCPV cells were capable to differentiate into osteoblasts and chondrocytes --- p.38 / Chapter 2.4.2 --- BRE expression is down-regulated when HUCPV cells begins to differentiate --- p.40 / Chapter 2.4.3 --- Silencing of BRE expression accelerates induction of osteogenesis and chondrogenesis --- p.40 / Chapter 2.4.4 --- Microarray analysis of BRE-silenced HUCPV cells --- p.42 / Chapter 2.4.4.1 --- Stemness factors --- p.43 / Chapter 2.4.4.2 --- Epigenetic regulation --- p.43 / Chapter 2.4.4.3 --- Signaling pathways crucial for stemness maintenance --- p.44 / Chapter 2.4.4.4 --- TGF-β signaling --- p.44 / Chapter 2.4.4.5 --- FGF signaling --- p.44 / Chapter 2.4.4.6 --- NOTCH signaling --- p.45 / Chapter 2.4.4.7 --- WNT signaling --- p.46 / Chapter 2.4.4.8 --- Homeobox transcription factors (HOX) --- p.46 / Chapter 2.4.4.9 --- Cell cycle regulation --- p.47 / Chapter 2.4.4.10 --- Chemokines and cytokines regulation --- p.48 / Chapter 2.4.4.11 --- Apoptosis --- p.49 / Chapter 2.4.5 --- BRE-silencing alters the cellular proteome of HUCPV cells --- p.50 / Chapter 2.4.5.1 --- BRE-silencing alters the cytoskeletal binding proteins of HUCPV cells --- p.51 / Chapter 2.4.5.2 --- BRE-silencing alters the expressions of stemness-related proteins in HUCPV cells --- p.52 / Chapter 2.4.5.3 --- BRE-silencing alters the expressions of apoptosis-related proteins in HUCPV cells --- p.53 / Chapter 2.5 --- Discussion --- p.86 / Chapter 2.5.1 --- Microarray study discussion --- p.87 / Chapter 2.5.2 --- Proteomic study discussion --- p.89 / Chapter 3 --- p.93 / Replicative senescence alters the transcriptome and proteome of HUCPV cells --- p.93 / Chapter 3.1 --- Introduction --- p.93 / Chapter 3.2 --- Materials and methods --- p.93 / Chapter 3.3 --- Results --- p.93 / Chapter 3.3.1 --- Microarray analysis of aged HUCPV cells --- p.94 / Chapter 3.3.1.1 --- Stemness factors --- p.95 / Chapter 3.3.1.2 --- Epigenetic regulation --- p.96 / Chapter 3.3.1.3 --- Senescence associated markers --- p.96 / Chapter 3.3.1.4 --- Chemokines and cytokines regulation --- p.97 / Chapter 3.3.1.5 --- Matrix metalloproteinases regulation --- p.97 / Chapter 3.3.1.6 --- WNT signaling --- p.98 / Chapter 3.3.1.7 --- Toll-like receptor signaling pathway --- p.98 / Chapter 3.3.2 --- Proteomic profiling of aged HUCPV cells --- p.98 / Chapter 3.4 --- Discussion --- p.117 / Chapter 3.4.1 --- Aging alters the transcriptome of HUCPV cells --- p.117 / Chapter 3.4.2 --- Aging alters the proteome of HUCPV cells --- p.118 / Chapter 4 --- p.121 / Osteogenic and chondrogenic differentiation capacities of HUCPV cells in silk fibroin scaffold --- p.121 / Chapter 4.1 --- Introduction --- p.121 / Chapter 4.2 --- Materials and methods --- p.121 / Chapter 4.2.1 --- Extraction of silk fibroin --- p.121 / Chapter 4.2.2 --- Fabrication of porous silk fibroin scaffold --- p.122 / Chapter 4.2.3 --- Scanning electron microscopy --- p.123 / Chapter 4.2.4 --- Cell culture --- p.123 / Chapter 4.3 --- Results --- p.124 / Chapter 4.4 --- Discussion --- p.132 / Chapter 5 --- p.133 / Conclusions --- p.133 / References --- p.135