O nicho endosteal da medula óssea abriga as células-tronco hemopoéticas (CTH) em quiescência/autorrenovação. As CTH podem ser classificadas em dois grupos: células que reconstituem a hemopoese em longo prazo (LT-CTH) e curto prazo (CT-CTH). Investigamos, neste trabalho, os efeitos da desnutrição proteica (DP) no tecido ósseo e a participação do nicho endosteal na sinalização osteoblasto-CTH. Para tanto, utilizamos camundongos submetidos à DP induzida pelo consumo de ração hipoproteica. Os animais desnutridos apresentaram pancitopenia e diminuição nas concentrações de proteínas séricas e albumina. Quantificamos as CTH por citometria de fluxo e verificamos que os desnutridos apresentaram menor porcentagem de LT-CTH, CT-CTH e de progenitores multipotentes (PMP). Avaliamos a expressão das proteínas CD44, CXCR4, Tie-2 e Notch-1 nas LT-CTH. Observamos diminuição da expressão da proteína CD44 nos desnutridos. Isolamos as células LT-CTH por cell sorting e avaliamos a expressão gênica de CD44, CXCR4 e NOTCH-1. Verificamos que os desnutridos apresentaram menor expressão de CD44. Em relação ao ciclo celular, verificamos maior quantidade de LT-CTH nas fases G0/G1. Caracterizamos as alterações do tecido ósseo femoral, in vivo. Observamos diminuição da densidade mineral óssea e da densidade medular nos desnutridos. A desnutrição acarretou diminuição da área média das seções transversais, do perímetro do periósteo e do endósteo na cortical do fêmur dos animais. E na região trabecular, verificou-se diminuição da razão entre volume ósseo e volume da amostra e do número de trabéculas, aumento da distância entre as trabéculas e prevalência de trabéculas ósseas em formato cilíndrico. Avaliamos a expressão de colágeno, osteonectina (ON) e osteocalcina (OC) por imuno-histoquímica, e de osteopontina (OPN) por imunofluorescência no fêmur e verificamos diminuição da marcação para OPN, colágeno tipo I, OC e ON nos desnutridos. Evidenciamos, pela técnica do Picrosírius, desorganização na distribuição das fibras colágenas e presença de fibras tipo III nos fêmures dos desnutridos, além de maior número de osteoclastos evidenciados pela reação da fosfatase ácida tartarato resistente. Os osteoblastos da região femoral foram isolados por depleção imunomagnética, imunofenotipados por citometria de fluxo e cultivados em meio de indução osteogênica. Observamos menor positividade para fosfatase alcalina e vermelho de alizarina nas culturas dos osteoblastos dos desnutridos. Avaliamos, por Western Blotting, a expressão de colágeno tipo I, OPN, osterix, Runx2, RANKL e osteoprotegerina (OPG), e, por PCR em tempo real, a expressão de COL1A2, SP7, CXCL12, ANGPT1, SPP1, JAG2 e CDH2 nos osteoblastos isolados. Verificamos que a desnutrição acarretou diminuição da expressão proteica de osterix e OPG e menor expressão gênica de ANGPT1. Avaliamos a proliferação das células LSK (Lin-Sca1+c-Kit+) utilizando ensaio de CFSE (carboxifluoresceína succinimidil ester). Foi realizada cocultura de células LSK e osteoblastos (MC3T3-E1) na presença e ausência de anti-CD44. Após uma semana, verificamos menor proliferação das LSK dos desnutridos. O bloqueio de CD44 das LSK do grupo controle diminuiu a proliferação destas em três gerações. Entretanto, nos desnutridos, esse bloqueio não afetou a proliferação. Concluímos que a DP promoveu alterações no tecido ósseo e nas CTH. Entretanto, não podemos afirmar que as alterações observadas no sistema hemopoético foram decorrentes de alterações exclusivas do nicho endosteal. / The bone marrow endosteal niche hosts hematopoietic stem cells (HSC) in quiescence/self-renewal. HSC can be classified into two groups: cells capable of renewing indefinitely (LT-HSC) or repopulating in the short term (ST-HSC). In this work, we investigated the effects of protein malnutrition (PM) on bone tissue and the involvement of the endosteal niche in osteoblast-CTH signaling. Therefore, we used mice subjected to PM induced by the consumption of hypoproteic feed. Malnourished animals presented pancytopenia and decreased concentration of serum protein and albumin. We quantified the HSC by flow cytometry and found that the malnourished ones had lower percentage of LT-HSC, ST-HSC and multipotent progenitors (MPP). We assessed the expression of the CD44, CXCR4, Tie-2 and Notch-1 proteins in LT-HSC. We observed decreased expression of CD44 protein with the malnourished ones. We isolated the LT-HSC cells by means of cell sorting and assessed the gene expression of CD44, CXCR4 and NOTCH-1. We found that malnutrition had lower expression of CD44. Regarding the cell cycle, we see greater amount of LT-HSC in the G0 and G1 phases. We characterized the changes of the femoral bone tissue in vivo. We observed a decrease in the bone mineral density and medullar density in malnourished animals. As for malnourished animals, the femoral cortical region showed a significant decrease in tissue area, periosteal and endosteal perimeter. The femoral trabecular region of malnourished animals showed decreased bone volume/tissue volume ratio, decreased trabecular number, increased trabecular separation and prevalence of rod-like trabeculae. We investigated the expression of collagen, osteonectin (ON) and osteocalcin (OC) by means of immunohistochemistry and the expression of osteopontin (OPN) by immunofluorescence and we found that malnourished animals showed decreased labeling for OPN, type I collagen, OC and ON in the cortical region of the femur. Picrosirius staining was used to analyze disorganization of collagen fibers and presence of type III fibers in the femurs of the malnourished. Cortical and trabecular regions of malnourished animals presented a higher number of osteoclasts as shown by tartrate-resistant acid phosphatase reaction. Moreover, osteoblasts were isolated from the femoral region by immunomagnetic depletion and immunophenotyped by flow cytometry and cultured in osteogenic induction medium. Results proved less positive for alkaline phosphatase and alizarin red in the cultures of osteoblasts of malnourished animals. We assessed, by means of Western blotting, type I collagen expression, OPN, osterix, Runx2, RANKL and osteoprotegerin (OPG) and, by real time PCR, the expression of COL1A2, SP7, CXCL12, ANGPT1, SPP1, JAG2 and CDH2 with the isolated osteoblasts. We found that malnutrition led to osterix and OPG decreased protein expression and lower ANGPT1 gene expression. We evaluated LSK cell (Lin-Sca1+c-Kit+) proliferation by CFSE (carboxyfluorescein succinimidyl ester). LSK cells and osteoblasts (MC3T3-E1) cocultures were performed in the presence and absence of anti-CD44. After a week, we found lower proliferation of LSK in the malnourished. The LSK CD44 blocking in the control group decreased the proliferation of these three generations. However, as for the malnourished, such blockage did not affect proliferation. We concluded that the PM has promoted changes in bone tissue and the CTH. However, we can\'t claim that the alterations observed in hematopoietic system were due to endosteal niche-only changes.

Chiu Lai-Ching. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 137-152). / Abstracts in English and Chinese. / Acknowledgement --- p.II / Abstract --- p.IV / Contents --- p.VIII / Abbreviations --- p.XIV / Chapter Chapter One --- General introduction / Chapter 1.1 --- Haemopoiesis --- p.1 / Chapter 1.1.1 --- Background --- p.1 / Chapter 1.1.2 --- Regulation --- p.2 / Chapter 1.1.2.1 --- Stromal cells --- p.2 / Chapter 1.1.2.2 --- Haemopoietic regulator --- p.3 / Chapter 1.1.2.3 --- Haemopoietic regulator receptors and signal transduction --- p.5 / Chapter 1.2 --- Disorder of haemopoiesis --- p.9 / Chapter 1.2.1 --- Causes --- p.9 / Chapter 1.2.2 --- Types of leukemia --- p.9 / Chapter 1.2.3 --- Treatment of leukemia --- p.10 / Chapter 1.3 --- Prostaglandins --- p.13 / Chapter 1.3.1 --- Introduction --- p.13 / Chapter 1.3.2 --- Types and biosynthesis --- p.14 / Chapter 1.3.3 --- Prostaglandin receptors --- p.15 / Chapter 1.3.4 --- Prostaglandins and cell differentiation --- p.17 / Chapter 1.3.4.1 --- PGD2 and cell differentiation --- p.19 / Chapter 1.3.4.2 --- PGE2 and cell differentiation --- p.20 / Chapter 1.3.4.3 --- PGJ2 and cell differentiation --- p.22 / Chapter 1.4 --- WEHI-3B JCS cells --- p.25 / Chapter 1.5 --- Aims of study --- p.27 / Chapter Chapter Two --- Roles of Prostaglandin D2，E2 and J2 in WEHI-3B JCS myeloid leukemia cell differentiation / Chapter 2.1 --- Introduction --- p.28 / Chapter 2.1.1 --- Morphological studies of JCS cells --- p.28 / Chapter 2.1.2 --- Methods in determining cell proliferation --- p.29 / Chapter 2.1.3 --- Methods in determining differentiated cells --- p.31 / Chapter 2.2 --- Materials --- p.33 / Chapter 2.2.1 --- Cell line --- p.33 / Chapter 2.2.2 --- Chemicals --- p.33 / Chapter 2.2.3 --- Solutions and buffers --- p.34 / Chapter 2.3 --- Methods --- p.36 / Chapter 2.3.1 --- Microscopic studies of the JCS cells --- p.36 / Chapter 2.3.1.1 --- Histochemical staining of JCS --- p.36 / Chapter 2.3.1.2 --- Transmission electronic microscopic --- p.36 / Chapter 2.3.2 --- [3H]-thymidine incorporation assay --- p.37 / Chapter 2.3.3 --- MTT assay --- p.37 / Chapter 2.4 --- Results --- p.38 / Chapter 2.4.1 --- Histochemical staining of JCS cells --- p.38 / Chapter 2.4.2 --- Electron microscopy --- p.40 / Chapter 2.4.3 --- "Effect of PGD2, E2 and J2 on JCS cells proliferation" --- p.44 / Chapter 2.4.4 --- "Effect of PGD2, E2 and J2 on JCS cells differentiation" --- p.48 / Chapter 2.5 --- Discussion --- p.53 / Chapter 2.5.1 --- Morphological differentiation of JCS cells --- p.53 / Chapter 2.5.2 --- The ultra-structures of JCS cells --- p.53 / Chapter 2.5.3 --- "Effect of PGD2, E2 and J2 on JCS cells proliferation" --- p.54 / Chapter 2.5.4 --- "Effect of PGD2, E2 and J2 on JCS cells differentiation" --- p.55 / Chapter Chapter Three --- Roles of Prostaglandin E2 in normal haemopoiesis and the detection of PGE2 receptors expression in JCS and bone marrow cells / Chapter 3.1 --- Introduction --- p.57 / Chapter 3.1.1 --- Colony assay --- p.57 / Chapter 3.1.2 --- The use of RT-PCR --- p.58 / Chapter 3.1.3 --- Prostaglandin E receptors --- p.59 / Chapter 3.2 --- Materials --- p.62 / Chapter 3.2.1 --- Bone marrow cells --- p.62 / Chapter 3.2.2 --- Cell line --- p.62 / Chapter 3.2.3 --- Chemicals --- p.62 / Chapter 3.2.4 --- Primers --- p.63 / Chapter 3.2.5 --- Solutions and buffers --- p.64 / Chapter 3.2.6 --- Enzymes and reagents --- p.65 / Chapter 3.3 --- Methods --- p.66 / Chapter 3.3.1 --- Titration of mouse IL-3 --- p.66 / Chapter 3.3.2 --- Determination of suitable IL-3 concentration for growth of bone marrow cells in colony assay --- p.66 / Chapter 3.3.2.1 --- Preparation of bone marrow cells --- p.66 / Chapter 3.3.2.2 --- Preparation of culture medium for colony assay --- p.67 / Chapter 3.3.3 --- Investigation of the effect of PGE2 on normal haemopoiesis by colony assay --- p.68 / Chapter 3.3.4 --- Detection of PGE2 receptors expression on JCS cells and bone marrow cells --- p.68 / Chapter 3.3.4.1 --- Preparation of cell lysates --- p.68 / Chapter 3.3.4.2 --- Preparation of total RNA of JCS cells and bone marrow cells --- p.68 / Chapter 3.3.4.3 --- RT-PCR --- p.69 / Chapter 3.4 --- Results --- p.71 / Chapter 3.4.1 --- Titration of mouse IL-3 --- p.71 / Chapter 3.4.2 --- Effect of mouse IL-3 on normal haemopoiesis --- p.73 / Chapter 3.4.3 --- Effect of PGE2 on mouse IL-3 driven normal bone marrow cell differentiation --- p.76 / Chapter 3.4.4 --- Analysis of total RNA prepared from uninduced JCS cells and bone marrow cells --- p.79 / Chapter 3.4.5 --- "Expression of gapdh in heart, liver, spleen, JCS and bone marrow cells" --- p.81 / Chapter 3.4.6 --- "Expression of PGE2 receptors in heart, liver, spleen, JCS and bone marrow cells" --- p.82 / Chapter 3.5 --- Discussion --- p.84 / Chapter 3.5.1 --- Effect of PGE2 on IL-3 driven normal bone marrow cells differentiation --- p.84 / Chapter 3.5.2 --- "Expression of PGE2 receptors in heart, liver, spleen, JCS and bone marrow cells" --- p.85 / Chapter Chapter Four --- Gene expression profile of JCS cells under 5 hours of PGE2 induction / Chapter 4.1 --- Introduction --- p.88 / Chapter 4.1.1 --- Review of methods studying differential gene expression --- p.88 / Chapter 4.1.2 --- The choice of method studying differential gene expression --- p.92 / Chapter 4.1.3 --- The microarray --- p.93 / Chapter 4.2 --- Materials --- p.95 / Chapter 4.2.1 --- Cell line --- p.95 / Chapter 4.2.2 --- Kits --- p.95 / Chapter 4.2.3 --- Chemicals --- p.95 / Chapter 4.2.4 --- Solutions and buffers --- p.96 / Chapter 4.2.5 --- Reagents --- p.97 / Chapter 4.3 --- Methods --- p.98 / Chapter 4.3.1 --- Preparation of total RNA from PGE2 induced JCS cells --- p.98 / Chapter 4.3.2 --- Preparation of cDNA probes --- p.98 / Chapter 4.3.2.1 --- Probe synthesis from total RNA --- p.98 / Chapter 4.3.2.2 --- Column chromatography --- p.99 / Chapter 4.3.3 --- Hybridizing cDNA probes to the Atlas Array --- p.99 / Chapter 4.4 --- Results --- p.101 / Chapter 4.4.1 --- Spectrophotometric analysis of total RNA after ethanol precipitation --- p.101 / Chapter 4.4.2 --- Hybridization of cDNA probes to Atlas Array --- p.102 / Chapter 4.5 --- Discussion --- p.121 / Chapter 4.5.1 --- Genes with increased expression --- p.121 / Chapter 4.5.2 --- Genes with decrease expression --- p.127 / Chapter 4.5.3 --- Study of gene expression profile by microarray --- p.128 / Chapter Chapter Five --- General discussion / Chapter 5.1 --- Introduction --- p.131 / Chapter 5.2 --- Roles of PGE2 in JCS cells differentiation --- p.131 / Chapter 5.3 --- Roles of PGE2 in normal haemopoiesis --- p.134 / Chapter 5.4 --- Further studies --- p.135 / References --- p.137

A caracterização fenotípica e o isolamento de células-tronco hematopoiéticas (CTH) podem fornecer informações relevantes quanto ao desenvolvimento biológico do sistema hematopoiético. A habilidade em detectar e purificar essas células implica no desenvolvimento de condições para manutenção e expansão dessas células em culturas in vitro. Na medicina veterinária, a purificação de células-tronco hematopoiéticas caninas (CTHc) vem de encontro com interesses em estabelecer métodos para o desenvolvimento de terapias celulares, principalmente em doenças que levam à aplasia medular ou anemia aplástica nesta espécie animal. Neste cenário, a escassez de informação acerca da caracterização fenotípica bem como sobre a capacidade de proliferação e pluripotência celular de CTHc precisa ser superada. O presente projeto visou o isolamento, a caracterização e a expansão, por meio da análise imunofenotípica e de ensaios CFU de células-tronco/progenitoras hematopoiéticas provenientes da fração estromal vascular (FEV) do tecido adiposo de cães. Os resultados demonstraram que o painel de imunofenotipagem CD45-/CD117+/CD34+constitui uma melhor estratégia de isolamento destas células em comparação ao painel CD45-/CD38-/low/CD34+. Além disso, a detecção da atividade da enzima aldeído desidrogenase (ALDH) também pode representar uma grande aliada no enriquecimento desta fração celular. Por meio das técnicas empregadas no presente projeto foi possível verificar que a freqüência de CTH é baixa em tecido adiposo canino. / Phenotypic characterization and isolation of hematopoietic stem cells (HSC) provide relevant information to allow us to elucidate the biological development of the hematopoietic system. The ability to detect and purify these cells involves the development of conditions for maintenance and expansion of these cells in in vitro cultures. In veterinary medicine, purification of canine hematopoietic stem cells (CTHc) is of interesting to provide methods for the development of cell-based therapies, particularly in diseases causing bone marrow aplasia or aplastic anemia in this species. In this scenario, the lack of information about the phenotypic characterization as well as on the ability of cell proliferation and pluripotency of CTHc needs to be overcome. The present study aimed at the isolation, characterization, and expansion, by means of immunophenotyping and CFU assays of stem cells/ progenitor hematopoietic from stromal vascular fraction (SVF) from adipose tissue of dogs. The results showed that immunophenotyping panel CD45-/CD117+/CD34+ is a better strategy for isolation of these cells compared to CD45-/CD38&#X2d/low/CD34+. Furthermore, the detection of the enzyme aldehyde dehydrogenase (ALDH) activity may also represent a great enrichment coupled to this cell fraction. By the techniques employed in this project we found that the frequency of CTH is low in canine adipose tissue.

Camundongos AIRmax e AIRmin exibem diferenças significativas no número médio de leucócitos migrantes e no conteúdo protéico do exsudato inflamatório produzido por partículas de poliacrilamida. Um dos fatores preponderantes para a maior capacidade inflamatória da linhagem AIRmax é a maior produção de neutrófilos maduros pela medula óssea. Assim, considerando a diferente capacidade de produção leucocitária, entre as linhagens AIRmax e AIRmin, nos propomos a estudar comparativamente nestas linhagens, o processo de mielopoese in vitro em resposta ao GM-CSF e ATRA. Verificamos que as células da medula óssea dos animais AIRmax apresentaram maior potencial proliferativo e maiores níveis de expressão de genes envolvidos nos estágios iniciais da mielopoese, do que os animais AIRmin. Além disso, o conteúdo protéico das células em cultura revelou diferenças quantitativas e qualitativas de proteínas provavelmente envolvidas no processo de mielopoese. / Mice AIRmax and AIRmin exhibit significant differences in the average number of migrating leukocytes and in the protein content of inflammatory exudate produced by polyacrylamide particles. This higher inflammatory capacity of the AIRmax mice is due to three convergent factors: higher local production of chemotactic factors, increased resistance of locally infiltrated neutrophils to spontaneous apoptosis and larger production of mature neutrophils by the bone marrow. Thus, considering the differential capacity of leukocyte production between AIRmax and AIRmin mice, we are studying comparatively the myelocytic differentiation process in vitro. We verified that the BM cells of AIRmax mice showed higher proliferation levels. In addition by qPCR technique it was verified a larger expression of genes involved in the initial stages of myelopoiesis in the AIRmax BM cultures. The analysis of BM cellular protein content by 2D gel electrophoresis revealed quantitative and qualitative differences between two mouse lines.

Chez les mammifères adultes, les cellules souches et les progéniteurs hématopoïétiques (CSPH) présents dans la moelle osseuse sont à l'origine de la production des cellules sanguines tout au long de la vie. L'auto-renouvellement, la prolifération et la différenciation des CSPH sont sous le contrôle d'un microenvironnement cellulaire spécifique appelé " niche ". Deux niches sont identifiés dans la moelle osseuse : une niche endostéale et vasculaire. Les processus moléculaires contrôlant les communications cellulaires entre les niches et les HSPC sont complexes et demeurent mal connues. Du fait de la conservation des facteurs de transcription et des voies de signalisations entre les mammifères et la drosophile, l'organe hématopoïétique de la drosophile : la glande lymphatique s'est avéré être un excellent modèle pour étudier les communications cellulaires entre les niches et les CSPH. La glande lymphatique est accolée au tube cardiaque (système vasculaire), qui contrôle la morphologie et la fonction du PSC (Posterior Signaling Center), un centre de signalisation contrôlant la différenciation des cellules immunitaires/sanguines dans la glande lymphatique. Au cours de mes travaux de thèse, j'ai réalisé un crible fonctionnel in vivo, pour déterminer si indépendamment de son effet sur le PSC, les cellules du tube cardiaque étaient capables de contrôler directement l'homéostasie de la glande lymphatique. La réalisation de ce crible m'a permis d'identifier quatre ligands produits par les cellules du tube cardiaque et requis au maintien des progéniteurs hématopoïétiques dans la glande lymphatique, notamment le ligand Branchless de la voie de signalisation FGF (Fibroblast Growth Factor). La perte de fonction du ligand FGF/Branchless dans le tube cardiaque ou du récepteur FGF/Breathless dans les progéniteurs hématopoïétiques entraine une différenciation accrue et une diminution du pool de progéniteurs dans la glande lymphatique. Mes résultats indiquent que le tube cardiaque a un rôle équivalent à une niche pour contrôler l'hématopoïèse dans la glande lymphatique et que la voie de signalisation FGF joue un rôle clé dans ces communications cellulaires. [...] / In adult mammals, hematopoietic stem cell and progenitors (HSPC) are present in the bone marrow and produce all blood cell type along the life. Renewal, proliferation and differentiation of the HSPC are tightly control by a specific microenvironment called the "niche", composed by an endosteal and a vascular niche. Molecular processes controlling cellular communications between niches and HSPC are complex and remain poorly understood. Since many transcription factors and signalization pathway are conserved in controlling hematopoiesis both in mammals and Drosophila, the Drosophila hematopoietic organ: the lymph gland became an excellent model to decipher cellular communications between the niche and HSPC. The lymph gland is aligned the cardiac tube (vascular system), which control the size and the function of the PSC (Posterior Signaling Center). The PSC is a signaling center controlling the differentiation of immune/blood cells in the lymph gland. During my PhD, I performed an in vivo functional screen to determine whether independently of its role on the PSC, cardiac cells were able to control directly the lymph gland homeostasis. The realization of this screen, allowed me to identify four ligands produced by cardiac tube cells and required to maintain lymph gland hematopoietic progenitors. One of this ligand is a FGF (Fibroblast Growth Factor) ligand Branchless. Knock down of FGF/branchless ligand in cardiac tube cells or FGF/Breathless receptor in hematopoietic progenitors lead to an increase in immune cells differentiation at the expense of the progenitor pool. My results establish that the cardiac tube plays a role similar to a niche in controlling lymph gland homeostasis and the FGF pathway plays a key role in this cellular communication. [...]

Les mitochondries sont des organelles qui jouent un rôle clé dans le métabolisme cellulaire en centralisant la production d'ATP à partir de nombreux substrats via la phosphorylation oxydative (OXPHOS). Les réactions enzymatiques impliquées dans ce processus régulent la prolifération, la différenciation, l'activation et l'auto renouvellement cellulaire. Le but de mon travail a été d'identifier le rôle de l'OXPHOS dans l'hématopoïèse et les mécanismes d'adaptation métabolique des cellules sanguines de la moelle, des lymphocytes B et des thymocytes à la dysfonction mitochondriale. L'atout majeur de cette étude est la génération de deux modèles murins déficients pour les protéines mitochondriales AIF ou NDUFS4 dans le système hématopoïétique. Nous avons observé que l'absence de ces protéines entraine des dysfonctions de l'OXPHOS sévère (AIF KO) ou modérée (NDUFS4 KO), entrainant des anomalies dans le développement hématopoïétique. Dans les deux modèles, en réponse au stress métabolique induit par la dysfonction de l'OXPHOS, les cellules de moelle activent la glycolyse anaérobie et la biogenèse mitochondriale tandis que les thymocytes favorisent l'assimilation et la dégradation des acides gras. Cette étude multiparamétrique, incluant des approches in vivo, ex vivo et in vitro, souligne l'importance de l'OXPHOS et du métabolisme mitochondrial dans le développement hématopoïétique. / By integrating different biochemical pathways and generating energy in form of ATP, through the electron transfer associated to oxidative phosphorylation (OXPHOS), mitochondria play a key role in cellular metabolism. In the hematopoietic cells, the mitochondrial metabolism appears implicated in proliferation, differentiation, activation and self-renewal regulation. In this context, the aim of my PhD work was to unravel the response of bone marrow (BM) cells, B-cells and thymocytes to OXPHOS dysfunction. To do that, we have developed two original hematopoietic cell-specific murine models deficient in the mitochondrial proteins AIF or NDUFS4. Severe (AIF KO) or moderate (NDUFS4 KO) OXPHOS dysfunction leads to pleiotropic consequences on hematopoietic development, including pancytopenia, BM aplasia, alterations in the development of the B-cell and erythroid lineages and T-cell developmental blockade at the immature stage. Strikingly, in response to OXPHOS dysfunction, BM cells stimulate anaerobic glycolysis and mitochondrial biogenesis, whereas thymocytes favor the assimilation and degradation of fatty acids. Overall my work, which included in vivo, ex vivo and in vitro approaches, underlines the relevance of OXPHOS and mitochondrial metabolism in the development of the hematopoietic cells.

"December 2001." Includes bibliographical references (leaves 178-225) Focuses on the ex vivo growth of human haemopoietic progenitor cells with the objective of defining culture conditions for generating myeloid post-progenitor cells for therapy

Uroplakin 1B (UPKIB) is an integral structural protein interacting with uroplakins 1A, 2 and 3 to form hexameric plaques along the bladder lumen in the asymmetric unit membrane of urothelial umbrella cells in humans and other mammals. UPKIB mRNA expression is deregulated in transitional cell carcinomas (TCCs), however the mechanisms of regulation of UPKIB have not been established. Using genome databases, a Xenopus UPKIB homologue was identified. Maximum Parsimony and BAMBE (Bayesian Analysis in Molecular Biology and Evolution) data support a close evolutionary relationship between mammalian and amphibian UPKIB mRNA. Using Unigene, UPKIB human expressed sequence tags were identified in tissues including brain, skeletal muscle and liver, suggesting the relatively widespread distribution of this membrane protein. The UPKIB genomic structure was also deduced using genome databases. Contig AC083800, identified in a high throughput genomic sequence database, spanned UPKIB and 9 exons and 8 introns were defined. A 67bp 5' untranslated region was identified using 5' rapid amplification of cDNA ends. This product was sequenced and a putative UPKIB promoter and transcription start site was deduced. Contig AC083800 spanned the transcription start site and putative promoter. Transcription factor binding motif prediction programs detected no TATA box, but did predict a CCAAT box and several binding motifs including 4 Sp-1 sites and a NFKB site. A weak CpG island was identified within a 0.5kb region including the putative promoter, exon 1 and intron 1, which was 54% GC rich with CpG:GpC ratio of 0.46, containing 15 CpG dinucleotides. Seven TCC cell lines and five peripheral blood lymphocyte samples were analysed for UPKIB expression using RT-PCR and two cell lines expressed UPKIB transcripts. Eleven CpG sites in the putative promoter were investigated for methylation using bisulfite modification analysis in normal PBL, TCC cell lines and patient TCC samples. An inverse correlation was established in TCC cell lines between UPKIB mRNA expression and degree of methylation. 5-Aza-2'deoxycytidine induced UPKIB mRNA expression in T24 cells, previously observed not to express UPKIB. Sequence analysis of patient samples revealed more complex CpG methylation patterns, reflecting tumour heterogeneity. In summary, the uroplakin 1B gene has been characterised and one mechanism of regulation of gene expression involves methylation. / Thesis (Ph.D.)--Dept of Surgery, 2003.

Includes nine pages of amendments. / Bibliography: leaves 140-211. / 211, [200] leaves, [12] leaves of plates : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Aims to determine the reason for the lack of ability of many myeloid leukaemic cell populations to stimulate allogeneic lymphocytes in mixed leucocyte culture (MLC), with a view to manipulating the immunogenicity of these cells for therapeutic purposes. / Thesis (Ph.D.)--University of Adelaide, Dept. of Microbiology and Immunology, 1995

"December 2001." / Includes bibliographical references (leaves 178-225) / xviii, 225 leaves : ill. (some col.), plates, charts ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Focuses on the ex vivo growth of human haemopoietic progenitor cells with the objective of defining culture conditions for generating myeloid post-progenitor cells for therapy / Thesis (Ph.D.)--University of Adelaide, Dept. of Molecular Biosciences, 2001