Made available in DSpace on 2016-01-26T12:51:30Z (GMT). No. of bitstreams: 1 heloisacaldas_tese.pdf: 13961449 bytes, checksum: adc041656d053c466bd2f0851119388c (MD5) Previous issue date: 2011-07-26 / Chronic renal failure (CRF) is characterized by progressive and irreversible loss of renal function and its treatment generates significant public spending for maintenance and care of patients on dialysis. Stem cell (SC) therapy, in its potential for treatment of chronic diseases, may be a promising strategy for repairing the damage from or slowing the progression of CRF. There are questions about cell type, quantity of cells, method and ideal place for deployment of SC and the role it plays in the repair of renal parenchyma. Objective: 1) To evaluate the effect of infusion of bone marrow derived cells (BMDC) in the treatment of experimental CRF; 2) Evaluate the combined effect of SC and biomaterial (BM) in the progression of CRF and study the effect of this therapy in different stages of CRF; 3) Evaluate the development of techniques for isolation and cultivation of human umbilical cord blood (HUCB) mesenchymal cells. Methods: Article 1: We used the 5/6 mass reduction model to induce experimental CRF. Kidney function was measured at the beginning of the experiment and 60 and 120 days after the surgery; Article 2: Animals were subdivided as to the amount of renal parenchyma injured (5/6 or 2/3), the use of BM as a scaffold to cell implantation, and cell type used (mononuclear or mesenchymal cells). Renal function was evaluated on days 0, 45, and 90 after surgery. Histological and immunohistochemical analyses were done in all groups at the end of the study; Article 3: Ten samples of HUCB were used and two different procedures for cultivation of mesenchymal stem cells (MSC) were tested: without Ficoll-Paque density gradient, to obtain nucleated cells; with Ficoll-Paque density gradient, for obtaining mononuclear cells. Results: Article 1: CRF progression analysis showed that treatment with BMDC significantly reduced the rate of decline of creatinine clearance (Clcr) when compared with the control group; Article 2:Treated animals showed significantly lower increases in serum creatinine and 24 hour proteinuria, and higher increases in Clcr after 90 days when compared to control animals in both models of CRF; Article 3: The MSC in culture from the method without Ficoll-Paque density gradient maintained growth forming confluent cell foci. Conclusions: Article 1: Progression of CRF can be delayed by injection of BMDC in the renal parenchyma; Article 2: a) Use of SC combined with BM can be an alternative way to administer BMDC; b) Cell therapy seems to be most effective when administered in less severe stages of CRF; Article 3: Nucleated cells without using Ficoll-Paque density gradient showed more efficiency in the cultivation of MSC from HUCB when compared with the procedure employing Ficoll-Paque density gradient / A insuficiência renal crônica (IRC) é caracterizada pela perda progressiva e irreversível da função renal e seu tratamento gera um gasto público significativo para manutenção de pacientes em tratamento dialítico. A terapia com células-tronco (CT), pelo seu potencial de tratamento das doenças crônicas, pode ser uma estratégia promissora para reparar ou retardar a progressão da IRC. Existem dúvidas sobre o tipo celular, a quantidade de células, o método e local ideal para implantação das CT e o papel por elas desempenhado na reparação do parênquima renal. Objetivos: 1) avaliar o efeito da infusão de células derivadas da medula óssea (CDMO) no tratamento da IRC experimental; 2) avaliar o efeito combinado das CT e biomaterial (BM) na progressão da IRC e estudar o efeito dessa terapia em diferentes estágios da IRC; 3) Avaliar o desenvolvimento de técnicas de isolamento e cultivo de células mesenquimais do sangue de cordão umbilical humano (SCU). Métodos: artigo 1: usamos o modelo de redução de massa 5/6 para induzir a IRC experimental. Função renal foi medida no início do experimento e 60 e 120 dias depois da cirurgia; artigo 2: animais foram subdivididos conforme a quantidade de parênquima renal lesado (5/6 ou 2/3), o uso de BM como arcabouço para o implante celular e o tipo de células utilizado (célula mononuclear ou mesenquimal). A função renal foi avaliada nos dias 0, 45 e 90 após cirurgia. Análise histológica e imunohistoquimica foram realizadas em todos os grupos ao final do estudo; artigo 3: Foram utilizadas dez amostras de SCU e testados dois diferentes procedimentos para cultivo de células-tronco mesenquimal (CTM): sem gradiente de densidade Ficoll-Paque, para obtenção de células nucleadas; por gradiente de densidade Ficoll-Paque, para obtenção de células mononucleares. Resultados: artigo 1: Análises da progressão da IRC mostraram que o tratamento com CDMO reduziu significativamente a taxa de declínio do clearance ( Clcr) quando comparados com o grupo controle; artigo 2: animais tratados apresentaram aumentos significativamente menores de creatinina sérica, proteinúria e Clcr maiores após 90 dias, quando comparado aos animais controles em ambos os modelos de IRC; artigo 3: as CTM em cultura provenientes do método sem gradiente de densidade Ficoll- Paque mantiveram o crescimento formando focos confluentes de células. Conclusões: artigo 1: a progressão da IRC pode ser retardada pela injeção de CDMO no parênquima renal; artigo 2: a) utilização da CT combinada com o BM pode ser uma via alternativa para administrar a CTMO; b) terapia celular parece ser mais eficaz quando administrada em estágios menos graves da IRC; artigo 3: As células nucleadas sem uso do gradiente de densidade Ficoll-Paque mostraram mais eficiente para o cultivo de CTM do SCU quando comparado ao procedimento com gradiente de densidade Ficoll-Paque.

Objetivos: Descrever o perfil e as complicações agudas mais importantes das crianças que receberam transplante de medula óssea (TMO) em nosso Serviço. Casuística e métodos: Análise retrospectiva de 41 pacientes menores de 21 anos transplantados entre Agosto de 1997 até Junho de 2002. Deste total 20 receberam transplante alogênico e 21 receberam transplante autogênico. Resultados: No TMO alogênico a média de idade foi de 8,9 + 5,4 anos, sendo 12 pacientes do sexo masculino. As fontes de células foram: medula óssea (MO) 12, sangue periférico (SP) 5, sangue de cordão umbilical não aparentado (SCU) 3. As doenças tratadas foram leucemia linfóide aguda (LLA) 7 pacientes, leucemia linfóide crônica (LMC) 2; leucemia mielóide aguda (LMA) 4; Síndrome mielodisplásica 2; Linfoma de Burkitt 1, Anemia aplástica grave 1; Anemia de Fanconi 1; Síndrome Chediak Higashi 1; Imunodeficiência congênita combinada grave 1. Um paciente desenvolveu doença do enxerto contra hospedeiro (DECH) aguda grau 2 e três DECH grau 4. Três pacientes desenvolveram DECH crônica. Todos haviam recebido SP como fonte de células. A sobrevida global foi de 70,0 + 10,3%. A principal causa do óbito foi DECH em 3 pacientes e sépse em outros 3. Todos os óbitos ocorreram antes do dia 100. Um dos pacientes que recebeu SCU está vivo em bom estado e sem uso de medicações 3 anos e 6 meses pós TMO. No TMO autogênico, a média de idade foi de 8,7 + 4,3 anos, sendo 11 pacientes do sexo masculino. As fontes de células foram SP 16, MO 3, SP + MO 2. As doenças tratadas foram: tumor de Wilms 5; tumores da família do sarcoma de Ewing 4; neuroblastomas 3; linfomas de Hodgkin 3; rabdomiossarcomas 2, tumor neuroectodérmico primitivo do SNC 2; Linfoma não Hodgkin 1; LMA 1. A sobrevida global está em 59,4 + 11,7 %. Cinco óbitos tiveram como causa a progressão da doença de base, um óbito ocorreu devido à infecção 20 meses pós TMO e dois óbitos foram precoces por sépse. As toxicidades mais comuns em ambos os grupos foram vômitos, mucosite, diarréia e dor abdominal. Infecções foram documentadas em 58,5% dos pacientes e 46,9% tiveram no mínimo um agente isolado na hemocultura. Os tempos de enxertia de neutrófilos e plaquetas correlacionaram-se com o número de células progenitoras infundidas. Conclusão: A sobrevida de nossos pacientes é semelhante à encontrada na literatura de outros serviços nacionais e internacionais. Não encontramos diferença entre os dois tipos de transplante com relação às toxicidades agudas e ás infecções. / Objectives: To describe the demografics and the most important acute clinical complications of the patients who underwent bone marrow transplantation (BMT) at our Service. Material and methods: A Retrospective analysis was performed including 41 patients treated between August 1997 and June 2002. Twenty patients had a allogeneic BMT and 21 autologous BMT. Results: Regarding allogeneic BMT the mean age was 8.9 + 5.4 years. Twelve patients were male. The stem cells sources were: bone marrow (BM) 12, peripheral blood (PB) 5, unrelated cord blood (UCB) 3. The diseases were acute lymphoid leukemia (ALL) in 7 patients, acute myeloid leukemia (AML) 4, Chronic myeloid leukemia (CML) 2, myelodysplastic syndrome 2, Burkitt’s lymphoma 1, severe combined immunodeficiency 1, Chediaki Higashi 1, Fanconi anemia 1, aplastic anemia 1. One patient developed grade 2 acute graft versus host disease (GVHD) and 3 had grade 4. Three patients developed chronic GVHD. All of them received PB as cell source. The overall survival was 70.0 + 10.3%. The main cause of death was GVHD in 3 patients and sepsis in the 3 other ones. All deaths occurred before day 100. One of the patients who received UCB is alive 3.5 years after the transplantation. Regarding autologous BMT, the mean age was 8,7 + 4,3 years. Eleven patients were male. The stem cell sources were: PB 16, BM 3, PB + BM 2. The diseases were: Wilms tumor 5, Ewing’s sarcoma family tumors 4, neuroblastoma 3, Hodgkin’s disease 3, non-Hodgkin’s lymphoma 1, rhabdomiossarcoma 2, Neuroectodermic tumor of the central nervous system 2, AML 1. The overall survival was 59.4 + 11.7%. Five patients died due to tumor relapse, 2 patients due to sepsis and one patient died in remission 20 months after BMT due to infection. In the whole group the most common toxicities were vomiting, mucositis, diarrhea and abdominal pain. Infections were documented in 58.5% of the patients and 46.9% had at least one agent isolated in the blood culture. The time to neutrophil and platelet engraftment were correlated to the number of hematopoietic stem cell infused. Conclusion: The overall survival in our patients is similar to the reported on the literature. We did not find differences between autologous and allogeneic BMT, regarding acute toxicities and infections.

Objetivos: Descrever o perfil e as complicações agudas mais importantes das crianças que receberam transplante de medula óssea (TMO) em nosso Serviço. Casuística e métodos: Análise retrospectiva de 41 pacientes menores de 21 anos transplantados entre Agosto de 1997 até Junho de 2002. Deste total 20 receberam transplante alogênico e 21 receberam transplante autogênico. Resultados: No TMO alogênico a média de idade foi de 8,9 + 5,4 anos, sendo 12 pacientes do sexo masculino. As fontes de células foram: medula óssea (MO) 12, sangue periférico (SP) 5, sangue de cordão umbilical não aparentado (SCU) 3. As doenças tratadas foram leucemia linfóide aguda (LLA) 7 pacientes, leucemia linfóide crônica (LMC) 2; leucemia mielóide aguda (LMA) 4; Síndrome mielodisplásica 2; Linfoma de Burkitt 1, Anemia aplástica grave 1; Anemia de Fanconi 1; Síndrome Chediak Higashi 1; Imunodeficiência congênita combinada grave 1. Um paciente desenvolveu doença do enxerto contra hospedeiro (DECH) aguda grau 2 e três DECH grau 4. Três pacientes desenvolveram DECH crônica. Todos haviam recebido SP como fonte de células. A sobrevida global foi de 70,0 + 10,3%. A principal causa do óbito foi DECH em 3 pacientes e sépse em outros 3. Todos os óbitos ocorreram antes do dia 100. Um dos pacientes que recebeu SCU está vivo em bom estado e sem uso de medicações 3 anos e 6 meses pós TMO. No TMO autogênico, a média de idade foi de 8,7 + 4,3 anos, sendo 11 pacientes do sexo masculino. As fontes de células foram SP 16, MO 3, SP + MO 2. As doenças tratadas foram: tumor de Wilms 5; tumores da família do sarcoma de Ewing 4; neuroblastomas 3; linfomas de Hodgkin 3; rabdomiossarcomas 2, tumor neuroectodérmico primitivo do SNC 2; Linfoma não Hodgkin 1; LMA 1. A sobrevida global está em 59,4 + 11,7 %. Cinco óbitos tiveram como causa a progressão da doença de base, um óbito ocorreu devido à infecção 20 meses pós TMO e dois óbitos foram precoces por sépse. As toxicidades mais comuns em ambos os grupos foram vômitos, mucosite, diarréia e dor abdominal. Infecções foram documentadas em 58,5% dos pacientes e 46,9% tiveram no mínimo um agente isolado na hemocultura. Os tempos de enxertia de neutrófilos e plaquetas correlacionaram-se com o número de células progenitoras infundidas. Conclusão: A sobrevida de nossos pacientes é semelhante à encontrada na literatura de outros serviços nacionais e internacionais. Não encontramos diferença entre os dois tipos de transplante com relação às toxicidades agudas e ás infecções. / Objectives: To describe the demografics and the most important acute clinical complications of the patients who underwent bone marrow transplantation (BMT) at our Service. Material and methods: A Retrospective analysis was performed including 41 patients treated between August 1997 and June 2002. Twenty patients had a allogeneic BMT and 21 autologous BMT. Results: Regarding allogeneic BMT the mean age was 8.9 + 5.4 years. Twelve patients were male. The stem cells sources were: bone marrow (BM) 12, peripheral blood (PB) 5, unrelated cord blood (UCB) 3. The diseases were acute lymphoid leukemia (ALL) in 7 patients, acute myeloid leukemia (AML) 4, Chronic myeloid leukemia (CML) 2, myelodysplastic syndrome 2, Burkitt’s lymphoma 1, severe combined immunodeficiency 1, Chediaki Higashi 1, Fanconi anemia 1, aplastic anemia 1. One patient developed grade 2 acute graft versus host disease (GVHD) and 3 had grade 4. Three patients developed chronic GVHD. All of them received PB as cell source. The overall survival was 70.0 + 10.3%. The main cause of death was GVHD in 3 patients and sepsis in the 3 other ones. All deaths occurred before day 100. One of the patients who received UCB is alive 3.5 years after the transplantation. Regarding autologous BMT, the mean age was 8,7 + 4,3 years. Eleven patients were male. The stem cell sources were: PB 16, BM 3, PB + BM 2. The diseases were: Wilms tumor 5, Ewing’s sarcoma family tumors 4, neuroblastoma 3, Hodgkin’s disease 3, non-Hodgkin’s lymphoma 1, rhabdomiossarcoma 2, Neuroectodermic tumor of the central nervous system 2, AML 1. The overall survival was 59.4 + 11.7%. Five patients died due to tumor relapse, 2 patients due to sepsis and one patient died in remission 20 months after BMT due to infection. In the whole group the most common toxicities were vomiting, mucositis, diarrhea and abdominal pain. Infections were documented in 58.5% of the patients and 46.9% had at least one agent isolated in the blood culture. The time to neutrophil and platelet engraftment were correlated to the number of hematopoietic stem cell infused. Conclusion: The overall survival in our patients is similar to the reported on the literature. We did not find differences between autologous and allogeneic BMT, regarding acute toxicities and infections.

Objetivos: Descrever o perfil e as complicações agudas mais importantes das crianças que receberam transplante de medula óssea (TMO) em nosso Serviço. Casuística e métodos: Análise retrospectiva de 41 pacientes menores de 21 anos transplantados entre Agosto de 1997 até Junho de 2002. Deste total 20 receberam transplante alogênico e 21 receberam transplante autogênico. Resultados: No TMO alogênico a média de idade foi de 8,9 + 5,4 anos, sendo 12 pacientes do sexo masculino. As fontes de células foram: medula óssea (MO) 12, sangue periférico (SP) 5, sangue de cordão umbilical não aparentado (SCU) 3. As doenças tratadas foram leucemia linfóide aguda (LLA) 7 pacientes, leucemia linfóide crônica (LMC) 2; leucemia mielóide aguda (LMA) 4; Síndrome mielodisplásica 2; Linfoma de Burkitt 1, Anemia aplástica grave 1; Anemia de Fanconi 1; Síndrome Chediak Higashi 1; Imunodeficiência congênita combinada grave 1. Um paciente desenvolveu doença do enxerto contra hospedeiro (DECH) aguda grau 2 e três DECH grau 4. Três pacientes desenvolveram DECH crônica. Todos haviam recebido SP como fonte de células. A sobrevida global foi de 70,0 + 10,3%. A principal causa do óbito foi DECH em 3 pacientes e sépse em outros 3. Todos os óbitos ocorreram antes do dia 100. Um dos pacientes que recebeu SCU está vivo em bom estado e sem uso de medicações 3 anos e 6 meses pós TMO. No TMO autogênico, a média de idade foi de 8,7 + 4,3 anos, sendo 11 pacientes do sexo masculino. As fontes de células foram SP 16, MO 3, SP + MO 2. As doenças tratadas foram: tumor de Wilms 5; tumores da família do sarcoma de Ewing 4; neuroblastomas 3; linfomas de Hodgkin 3; rabdomiossarcomas 2, tumor neuroectodérmico primitivo do SNC 2; Linfoma não Hodgkin 1; LMA 1. A sobrevida global está em 59,4 + 11,7 %. Cinco óbitos tiveram como causa a progressão da doença de base, um óbito ocorreu devido à infecção 20 meses pós TMO e dois óbitos foram precoces por sépse. As toxicidades mais comuns em ambos os grupos foram vômitos, mucosite, diarréia e dor abdominal. Infecções foram documentadas em 58,5% dos pacientes e 46,9% tiveram no mínimo um agente isolado na hemocultura. Os tempos de enxertia de neutrófilos e plaquetas correlacionaram-se com o número de células progenitoras infundidas. Conclusão: A sobrevida de nossos pacientes é semelhante à encontrada na literatura de outros serviços nacionais e internacionais. Não encontramos diferença entre os dois tipos de transplante com relação às toxicidades agudas e ás infecções. / Objectives: To describe the demografics and the most important acute clinical complications of the patients who underwent bone marrow transplantation (BMT) at our Service. Material and methods: A Retrospective analysis was performed including 41 patients treated between August 1997 and June 2002. Twenty patients had a allogeneic BMT and 21 autologous BMT. Results: Regarding allogeneic BMT the mean age was 8.9 + 5.4 years. Twelve patients were male. The stem cells sources were: bone marrow (BM) 12, peripheral blood (PB) 5, unrelated cord blood (UCB) 3. The diseases were acute lymphoid leukemia (ALL) in 7 patients, acute myeloid leukemia (AML) 4, Chronic myeloid leukemia (CML) 2, myelodysplastic syndrome 2, Burkitt’s lymphoma 1, severe combined immunodeficiency 1, Chediaki Higashi 1, Fanconi anemia 1, aplastic anemia 1. One patient developed grade 2 acute graft versus host disease (GVHD) and 3 had grade 4. Three patients developed chronic GVHD. All of them received PB as cell source. The overall survival was 70.0 + 10.3%. The main cause of death was GVHD in 3 patients and sepsis in the 3 other ones. All deaths occurred before day 100. One of the patients who received UCB is alive 3.5 years after the transplantation. Regarding autologous BMT, the mean age was 8,7 + 4,3 years. Eleven patients were male. The stem cell sources were: PB 16, BM 3, PB + BM 2. The diseases were: Wilms tumor 5, Ewing’s sarcoma family tumors 4, neuroblastoma 3, Hodgkin’s disease 3, non-Hodgkin’s lymphoma 1, rhabdomiossarcoma 2, Neuroectodermic tumor of the central nervous system 2, AML 1. The overall survival was 59.4 + 11.7%. Five patients died due to tumor relapse, 2 patients due to sepsis and one patient died in remission 20 months after BMT due to infection. In the whole group the most common toxicities were vomiting, mucositis, diarrhea and abdominal pain. Infections were documented in 58.5% of the patients and 46.9% had at least one agent isolated in the blood culture. The time to neutrophil and platelet engraftment were correlated to the number of hematopoietic stem cell infused. Conclusion: The overall survival in our patients is similar to the reported on the literature. We did not find differences between autologous and allogeneic BMT, regarding acute toxicities and infections.

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.

MicroRNA (miRNA) are small non-coding 21-23 nucleotides long one strand RNAs. They are among the major posttranscriptional regulators of gene expression that regulate both physiological and pathological processes. Some of microRNAs, amount of their expression respectively, are specific only for certain type of tissue or pathological condition. The hypothesis for my diploma thesis was that gene expression of 28 cardiovascular disease associated microRNAs (miR-1-3p, miR-16-5p, miR-17-5p, miR- 20a-5p, miR-20b-5p, miR-21-5p, miR-23a-3p, miR-24-3p, miR-26a-5p, miR-29a-3p, miR-92a-3p, miR-100-5p, miR-103a-3p, miR-125b-5p, miR-126-3p, miR-130b-3p, miR-133a-3p, miR-143-3p, miR-145-5p, miR-146a-5p, miR-181-5p, miR-195-5p, miR- 199a-5p, miR-210-3p, miR-221-3p, miR-342-3p, miR-499a-5p, miR-574-3p) would differ in umbilical cord blood between groups of women with physiological pregnancies (FG), gestational hypertension (GH), preeclampsia (PE) and fetal growth restriciton (FGR). The studied cohort consisted of 184 pregnant women involving 44 controls, 47 GH pregnancies, 56 PE pregnancies and 37 FGR pregnancies. Relative quantification of microRNAs was performed by quantitative real-time PCR. Results showed a trend to miR-195-5p down-regulation in umbilical cord blood of GH patients. On the other hand, mild PE...

L’hypoxo-ischémie (HI) cérébrale néonatale représente une des principales causes de mortalité et de morbidité chez les nouveau-nés. Sa physiopathologie implique différents processus délétères menant vers la perte neuronale et responsables de séquelles neuro-cognitives. L'hypothermie thérapeutique est le seul traitement actuel mais est insuffisant. Cette étude a caractérisé et comparé l’effet de deux types de cellules issues du sang de cordon humain, les cellules mononuclées (HUCBCs) et les progéniteurs endothéliaux tardifs (ECFCs) sur l’amélioration des scores neuro-comportementaux mais aussi à l’échelle moléculaire et fonctionnelle dans le modèle d’hypoxo-ischémie néonatale à court (7 jours après l’épisode ischémique) et long terme (12 semaines après l’épisode ischémique).L’injection intrapéritonéale d'ECFCs ou de HUCBCs, 2 jours après HI, améliore les capacités de motricité et de mémorisation précoce et tardive des animaux à l’âge adulte, et diminue les comportements anxieux. Ces résultats sont associés à une augmentation de la densité capillaire en temps précoce et tardif. L’imagerie de perfusion cérébrale SPECT/CT a objectivé une restauration complète de la perfusion cérébrale de l’hémisphère lésé à l’âge adulte par les deux types cellulaires. Ces observations tardives sont associées à un effet protecteur précoce de ces cellules sur l’augmentation de la survie neuronale et la diminution de l’astrogliose réactionnelle ou encore sur la composante inflammatoire par diminution de l’activation microgliale pro-inflammatoire au niveau striatal. Les résultats de cette étude ouvrent ainsi de nouvelles perspectives pour l’usage des ECFCs dans le traitement de l’HI néonatale. / Neonatal hypoxic-ischemic encephalopathy (NHIE) is a dramatic perinatal complication, associated with poor neurological prognosis despite neuroprotection by therapeutic hypothermia, in the absence of an available curative therapy. We evaluated and compared ready-to-use human umbilical cord blood cells (HUCBCs) and bankable but allogeneic endothelial progenitors (ECFCs) as cell therapy candidate for NHIE. We compared benefits of HUCBC and ECFC transplantation 48 hours after injury in male rat NHIE model, based on the Rice-Vannucci approach. Based on behavioral tests, immune-histological assessment and metabolic imaging of brain perfusion using SPECT, HUCBC or ECFC administration provided equally early and sustained functional benefits, up to 8 weeks after injury. These results were associated with total normalization of injured hemisphere cerebral blood flow assessed by SPECT/CT imaging. In conclusion, even if ECFCs represent an efficient candidate, HUCBCs’ autologous criteria and easier availability make them the ideal candidate for hypoxic-ischemic cell therapy.

Der ischämische Schlaganfall ist global eine der bedeutendsten Volkskrankheiten. Die derzeit verfügbaren kurativen Therapieoptionen werden vorrangig durch ein enges therapeutisches Zeitfenster limitiert. Ziel der aktuellen Schlaganfallforschung ist die Entwicklung von über dieses Zeitfenster hinaus wirksamen Therapien. Ein vielversprechender neuer Ansatz ist die experimentelle Behandlung mit humanen Nabelschnurblutzellen. Diese Arbeit erforscht das therapeutische Zeitfenster für die systemische Therapie des ischämischen Schlaganfalls mittels mononukleärer Nabelschnurblutzellen (hUCB MNC) in spontanhypertensiven Ratten nach permanentem Verschluss der Arteria cerebri media (pMCAO). Hierzu wurden die Therapiezeitpunkte 4, 24, 72, 120 Stunden und 14 Tage nach experimentellem Schlaganfall in einem komplexen Studiendesign inklusive neurofunktioneller Tests, magnetresonanztomographischer und immunhistochemischer Verfahren untersucht. In vitro wurde der Einfluss kokultivierter hUCB MNC auf Nekrose und Apoptose in neuralem Gewebe unter Sauerstoff-Glukose-Deprivation betrachtet. Die Studie ergab eine verbesserte funktionelle Rekonvaleszenz und eine geringere Ausprägung von Atrophie und Astroglianarbe bei Therapie innerhalb eines 72- Stunden-Zeitfensters. In vitro wurde eine signifikante Reduktion von Nekrose und Apoptose durch kokultivierte hUCB MNC beobachtet. Eine histologische Relokalisierung der intravenös applizierten Zellen war in keiner Therapiegruppe möglich. Die Integration der hUCB MNC ins Hirnparenchym stellt somit keine conditio sine qua non für die funktionelle Erholung nach Schlaganfall dar. Trotz des beobachteten erweiterten Zeitfensters ist die Translation dieses Therapieansatzes in die klinische Realität kritisch zu diskutieren, da weiterführende Studien unserer Arbeitsgruppe eine limitierte Wirksamkeit unter sehr praxisnahen Bedingungen (z.B. Einsatz kryokonservierter hUCB MNC) gezeigt haben. / Experimental treatment strategies using human umbilical cord blood mononuclear cells (hUCB MNCs) represent a promising option for alternative stroke therapies. An important point for clinical translation of such treatment approaches is knowledge on the therapeutic time window. Although expected to be wider than for thrombolysis, the exact time window for hUCB MNC therapy is not known. Our study aimed to determine the time window of intravenous hUCB MNC administration after middle cerebral artery occlusion (MCAO). Male spontaneously hypertensive rats underwent MCAO and were randomly assigned to hUCB MNC administration at 4h, 24h, 72h, 120h or 14d. Influence of cell treatment was observed by magnetic resonance imaging on days 1, 8 and 29 following MCAO and by assessment of functional neurological recovery. On day 30, brains were screened for glial scar development and presence of hUCB MNCs. Further, influence of hUCB MNCs on necrosis and apoptosis in post-ischemic neural tissue was investigated in hippocampal slices cultures. Transplantation within a 72h time window resulted in an early improvement of functional recovery, paralleled by a reduction of brain atrophy and diminished glial scarring. Cell transplantation 120h post MCAO only induced minor functional recovery without changes in the brain atrophy rate and glial reactivity. Later transplantation (14d) did not show any benefit. No evidence for intracerebrally localized hUCB MNCs was found in any treatment group. In vitro hUCB MNCs were able to significantly reduce post-ischemic neural necrosis and apoptosis. Our results for the first time indicate a time window of therapeutic hUCB MNC application of at least 72 hours. The time window is limited, but wider than compared to conventional pharmacological approaches. The data furthermore confirms that differentiation and integration of administered cells is not a prerequisite for poststroke functional improvement and lesion size reduction.

Les cellules souches hématopoïétiques (CSH) sont des cellules souches adultes, responsables du maintien du système sanguin tout au long de la vie des vertébrés. Les CSH sont des cellules multipotentes spécialisées qui possèdent deux propriétés principales : leur capacité à se différencier en de multiples lignées et leur capacité à créer d'autres cellules souches (c'est-à-dire l'autorenouvellement). Grâce à ces caractéristiques, les CSH ont un énorme potentiel thérapeutique. En effet, la transplantation de CSH constitue à ce jour une option de choix pour le traitement de plusieurs maladies et troubles hématologiques. Les CSH ne se retrouvent que dans certains échantillons biologiques comme la moelle osseuse, les cellules mobilisées de la moelle osseuse dans le sang périphérique ou les cellules de sang de cordon ombilical. Les applications cliniques des CSH sont souvent limitées en raison de leur faible fréquence dans les échantillons biologiques, c’est pourquoi leur expansion ex vivo est un domaine de recherche en plein essor. Des approches basées sur des petites molécules pour amplifier le nombre les cellules couches ex vivo ont été testées avec succès pour permettre la prolifération des cellules et freiner leur différentiation. Notre groupe a contribué à ce domaine en identifiant la petite molécule UM171 qui peut amplifier les CSH ex vivo par reprogrammation épigénétique. Dans le cadre des efforts d’expansion ex vivo des CSH, un obstacle majeur est la caractérisation des cellules qui ont proliféré ex vivo afin d’évaluer de façon exhaustive le potentiel des greffons pour des applications ultérieures. La caractérisation phénotypique des CSH amplifiées ex vivo est une approche prometteuse pour aider à isoler et à purifier les cellules souches. Les travaux de cette thèse explorent l'association de l'immunophénotype à la fonctionnalité des cellules souches pour nous aider à définir l'hétérogénéité des cellules amplifiées. Au chapitre 2, en utilisant un profilage de cellules amplifiées basée sur le transcriptome, nous avons pu identifier CEACAM1 comme un nouveau marqueur fonctionnel des CSH. Concomitamment, au chapitre 3, nous appliquons une approche alternative basée sur le protéome de la surface cellulaire pour aider à caractériser le phénotype des cellules souches et progénitrices hématopoïétiques (CSPH) amplifiées ex vivo afin d'identifier GPA33 en comme marqueur probable de CSH. Les marqueurs de surface compatibles avec la culture constituent un excellent outil pour un isolement prospectif rapide et des manipulations in vitro et in vivo supplémentaires pour permettre une meilleure compréhension de la biologie des cellules souches. La caractérisation des HSPC expansées ex vivo est donc une tentative de combler le fossé et de permettre des stratégies thérapeutiques améliorées. / Hematopoietic stem cells (HSCs) are responsible for maintaining the blood system throughout the lifespan of vertebrates. HSCs are specialized multipotent cells that have two main properties – their ability to differentiate into multiple lineages and their ability to create more stem cells (i.e. self-renewal). Due to these special abilities, HSCs have tremendous therapeutic potential. HSCs thus to date are the best curative measure against most hematological malignancies and disorders. HSCs occur in limited frequency and can be found only from certain conserved sources like the bone marrow or mobilized cells from the bone marrow in the peripheral blood or umbilical cord blood cells. Clinical applications of HSCs are often restricted due to their low occurring frequencies, therefore ex vivo expansion is a growing research field. Small molecule-based approaches to expand stem cells ex vivo have been successfully tested to allow for proliferation of cells by curbing their differentiation. Our group has contributed to this field by the identification of the small molecule UM171 which can expand hematopoietic stem and progenitor cells (HSPCs) ex vivo via epigenetic reprogramming. To expand HSPCs ex vivo a major hurdle is the proper characterization of the ex vivo expanded cells to evaluate the full potential of grafts for further downstream applications. Phenotypic dissociation of ex vivo expanded HSPCs is a prospective tool to help isolate and purify stem cells. Identification of culture-compatible surface markers is therefore the first step to help characterize the ex vivo expanded cells. The work in this thesis explores the association of immunophenotype to the functionality of stem cells to help us delineate the heterogeneity of expanded cells. In Chapter 2, using transcriptome-based interrogation of expanded cells, we were able to identify CEACAM1 as a novel functional marker of HSCs. Whereas, in Chapter 3 we apply an alternative cell surface proteome-based approach to help characterize the phenotype of ex vivo expanded HSPCs to identify GPA33 as a probable HSC marker. Culture-compatible surface markers make for an excellent tool for rapid prospective isolation and additional in vitro and in vivo manipulations to allow a better understanding of stem cell biology. Characterization of ex vivo expanded HSPCs is thus an attempt to help bridge the gap and allow for enhanced therapeutic strategies.

Introduction : La Vitamine A (rétinol, ROL) et son métabolite l’acide rétinoïque (AR) sont essentielles pour l’embryogénèse. L’excès comme l’insuffisance d’AR sont nocives. L’AR est régularisé dans l’embryon par des gènes spécifiques (ALDH, CRABP, CYP). Hypothèse : Les grandes variations d’AR dans le plasma des adultes normaux, nous ont orienté à mesurer les rétinoïdes (ROL et RA) dans le sang de cordon ombilical, pour évaluer des corrélations avec des polymorphismes des gènes impliquées dans le métabolisme de l’AR et le développement rénal-(RALDH2, CRABP2, CYP26A1; B1). Vérifier pour des corrélations entre ces rétinoïdes et/ou avec la taille de reins à la naissance. Méthodes : Extraction du ROL et RA du sang de cordon ombilical de 145 enfants et analyse par HPLC. Le volume des reins a été mesuré par ultrasonographie et l’ADN génomique leucocytaire extrait (FlexiGene DNA-Kit). 10 échantillons d’ADN ont été exclus (qualité). Les htSNP : ALDH1A2, CRABP2, CYP26A1;B1 du génome humain (HapMap) ont été séquencés et génotypés (Sequenom iPlex PCR).Des testes bio-statistiques des fréquences génotypiques et alléliques ont été effectués (Single-Locus, χ2, Kruskal-Wallis, Allelic-Exact).Des corrélations (ROL, RA, SNPs, V-reins) ont été analysés (Kendall-tau /Oakes). Résultats : La Δ RA (0.07-550.27 nmol/l) non corrélé avec la Δ ROL (51.39-3892.70 nmol/l). Il n’y a pas d’association ROL ou RA avec les volumes des reins ou avec les SNPs/ CYP21A1;B1. Corrélations trouvées : 1. (p=0.035), polymorphisme génétique ALDH1A2-SNP (rs12591551:A/C) hétérozygote/CA, (25enfants, 19%) avec moyennes d’AR (62.21nmol/l). 2. (p=0.013), polymorphisme CRABP2-SNP (rs12724719:A/G) homozygote/AA (4 enfants, 3%) avec hautes valeurs moyennes d’AR (141,3 nmol/l). Discussion-Conclusion : Les grandes ΔRA suggèrent une variabilité génique individuelle du métabolisme de ROL. Les génotypes (CA)-ALDH1A2/ SNP (rs12591551:A/C) et (AA) -CRABP2/SNP (rs12724719:A/G) sont associés à des valeurs moyennes hautes d’AR, pouvant protéger l’embryogénèse lors d’une hypovitaminose A maternelle. / Introduction: Vitamin A (retinol, ROL) modulate the embryogenesis thorough RA, its metabolite. Excess or deficiency being pathologic, the RA is tight regulated in the embryo thorough specific genes (ALDH, CRABP, CYP, etc.) important for Vitamin A metabolism. Hypothesis: High RA variations in healthy adults plasma, oriented to ROL, RA evaluation in human cord blood, in regard of possible correlations with polymorphisms of genes involved in RA metabolism and kidney development (RALDH2, CRABP2, CYP26A1,B1). Correlations between ROL and RA and/or with birth kidney size might also occur. Methods: Cord blood ROL and RA were extracted and HPLC analysed, from 145 Montreal healthy newborns. Kidney volumes already measured by ultrasonography. Genomic leucocytary DNA extraction was performed with FlexiGene DNA-Kit. 10 samples excluded (DNA quality). htSNP choices: ALDH1A2, CRABP2, CYP26A1;B1 were made on HapMap human genome. Sequencing, genotyping (Sequenom iPlex PCR) was made for these genes eventual SNPs. Biostatistics tests for genotype and allelic frequencies (Single-Locus, χ2, Kruskal-Wallis, Allelic-Exact) and Kendall-tau /Oakes analysis for eventual ROL, RA, SNPs, V-reins correlations, were performed. Results: No correlation found between Δ RA (0.07-550.27 nmol/L) and Δ ROL (51.39-3892.70 nmol/L). No association ROL or RA with kidney volumes nor with SNPs/ CYP21A1;B1. Found correlations: 1. (p=0.035), polymorphism ALDH1A2-SNP (rs12591551:A/C) heterozygous/CA, (25babies, 19%) with RA (mean ~62.21nmol/L). 2. (p=0.013), polymorphism CRABP2-SNP (rs12724719: A/G) homozygous/AA (4babies, 3%) with RA (mean~141, 3 nmol/L). Discussion/Conclusion: Big Δ RA not correlated with Δ ROL suggests individual genetic variance on RA metabolism. Genotypes (CA)-ALDH1A2/SNP (rs12591551:A/C) and (AA)-CRABP2/SNP (rs12724719: A/G) are associated with high cord blood RA mean and may be embryogenesis protective in a maternal hypovitaminosis-A, environment.