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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Roles of CRBP1, N-cadherin and SOX11 in differentiation and migration of bone marrow-derived mesenchymal stem cells.

January 2012 (has links)
前言:間充質幹細胞容易擴增並且能分化為成骨細胞、軟骨細胞和脂肪細胞,並且能對炎症、感染和損傷做出反應,並且遷移到相應的組織部位。這些特性使間充質幹細胞成為骨骼組織工程學中非常重要的細胞來源。外周血間充質幹細胞是一種存在於血液中的間充質幹細胞,而主要的間充質幹細胞存在與骨髓中,被稱之為骨髓間充質幹細胞。在我們實驗室之前的研究中通過DNA微陣列發現外周血間充質幹細胞中很多基因的表達與骨髓間充質幹細胞有很大區別。這其中的一些基因可能參與調控間充質幹細胞的分化和歸巢,我們從中挑選了三個變化比較明顯的基因--CRBP1, N-cadherin和 SOX11做進一步研究。本研究的目的在於研究CRBP1, N-cadherin和 SOX11在骨髓間充質幹細胞分化和遷移中的作用及相關機理。 / 方法:培養的骨髓間充質幹細胞來源於6-8周大小的SD大鼠。細胞的表型經過多分化潛能測試(成骨分化,成脂分化和成軟骨分化)和流式細胞儀檢驗。克隆大鼠的CRBP1, N-cadherin和SOX11基因到慢病毒載體。而且還設計了針對CRBP1和 N-cadherin的shRNA及非特異性對照shRNA。慢病毒由暫態轉染293FT細胞產生。細胞遷移實驗採用了BD Falcon的細胞遷移系統(cell culture insert)。實驗採用了定量PCR、免疫共沉澱、western雜交和雙螢光報告檢驗。對於體內實驗,細胞經感染帶有不同基因的病毒後,種植到Si-TCP材料並移植到裸鼠皮下。8周後,收集樣品進行組織學和免疫組織學分析。最後,我們建立了大鼠的股骨開放式骨折模型,並在4天后將SOX11基因修飾的間充質幹細胞通過心臟注射打到大鼠體內。4周後,收集股骨骨折樣品並進行microCT、力學測試和組織學分析。 / 結果:CRBP1過表達能夠促進骨髓間充質幹細胞的成骨分化潛能,並能抑制其成脂分化。進一步的機理研究表明CRBP1可以通過與RXRα的蛋白相互作用抑制RXRα誘導的β-catenin降解,從而維持β-catenin和磷酸化-ERK1/2在較高的水準,導致間充質幹細胞成骨能力增強;N-cadherin過表達可以促進間充質幹細胞的遷移,但是卻通過下調β-catenin和磷酸化ERK1/2抑制其成骨分化。過表達SOX11可以通過增強BMP信號通路促進三系分化。SOX11還可以通過啟動CXCR4的表達來促進細胞遷移。最後,在大鼠的股骨開放骨折模型上通過系統注射,我們證明穩定過表達SOX11的間充質幹細胞遷移到骨折部位的數量明顯增加。這些細胞到達骨折部位以後可以起始骨痂的鈣化,促進骨折的修復。 / 結論:本研究證明CRBP1, N-cadherin 和SOX11具有調節骨髓間充質幹細胞遷移和/或分化的功能。這些基因也許會成為幹細胞治療的新靶點。系統注射SOX11基因修飾的骨髓間充質幹細胞對於骨折修復可能具有較好的療效。本研究初步研究了CRBP1, N-cadherin 和SOX11在間充質幹細胞中的作用,為探討以間充質幹細胞為基礎的組織工程的某些新臨床應用提供了一些線索。 / Introduction: Mesenchymal stem cells (MSCs) can be easily harvested, expanded, and have the capability of differentiating into osteoblasts, chondrocytes and adipocytes, and they can home to various tissues in response to stimuli such as inflammation, infection and injuries. MSCs are therefore valuable cell source for musculoskeletal tissue engineering. Peripheral blood-derived MSCs (PB-MSCs) are one kind of MSCs that reside in peripheral blood, whereas the main source of MSCs is bone marrow-derived MSCs (BM-MSCs). In our previous study, we found many genes were differentially expressed in the PB-MSCs compared to their counterpart BM-MSCs demonstrated by microarray analysis, among which the effects of CRBP1, SOX11 and N-cadherin on MSCs in terms of migration and differentiation are studied. / Methods: BM-MSCs and PB-MSCs were cultured from 6-8 weeks SD rats. The phenotypes of MSCs were characterized by tri-lineage (adipo-, osteo- and chondrogenic) differentiation and flow cytometry analysis. The genes encoding rat CRBP1, SOX11 and N-cadherin were cloned into lentiviral vectors respectively. shRNAs targeting CRBP1, N-cadherin, and one nonspecific shRNA were designed. Pseudo-lentivirus was produced by transient transfection of 293FT cells. Cell migration was examined using transwell insert culture system. Quantitative RT-PCR, CO-IP, western blot and dual-luciferase assay were employed in the studies. For in vivo study, MSCs transduced with different genes were seeded on Si-TCP scaffolds and implanted subcutaneously in nude mice. 8 weeks later, the samples were collected for histological and immunohistological analysis. Finally, an open femoral fracture model was established in 8-week old SD rats, SOX11-modified MSCs were injected at four days after fracture. At 4-week after MSCs injection, the femurs were collected for microCT, mechanical test and histological analysis. / Results: For CRBP1gene, our results showed that CRBP1 overexpression promoted osteogenic differentiation of BM-MSCs, while inhibited their adipogenic differentiation. We demonstrated that CRBP1 promoted osteogenic differentiation by inhibiting RXRα-induced β-catenin degradation through physical interactions, and maintaining β-catenin and pERK1/2 at higher levels. For N-cadherin gene, we found that N-cadherin overexpression promoted MSCs migration, and suppressed osteogenic potential of MSCs through inhibiting ERK and β-catenin signaling pathways. For SOX11 gene, we demonstrated that SOX11 overexpression enhanced the adipo-, osteo- and chondrogenic differentiation of BM-MSCs, through enhancing BMP signaling pathways. The migration capacity of BM-MSCs was also enhanced when Sox-11 was overexpressed, through activating CXCR4 expression. Finally, in the open femur fracture model we demonstrated that a larger number of SOX11-overexpressing BM-MSCs migrated to the fracture site, initiated earlier callus ossification and improved bone fracture healing quality. / Conclusions: This study demonstrated that CRBP1, N-cadherin and SOX11 gene can regulate the migration and/or differentiation potentials of BM-MSCs. These genes may become new therapeutic targets in stem cell therapy applications. Systemic administration of genetically modified SOX11-overexpressing BM-MSCs may be useful in promoting fracture healing. Overall, this study defined some unknown functions of CRBP1, N-cadherin and SOX11 in MSCs and shed the lights on some novel therapeutic implications for MSCs-based tissue engineering. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Xu, Liangliang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 128-144). / Abstract also in Chinese. / Declaration --- p.i / Abstract --- p.ii / 摘要 --- p.v / Acknowledgements --- p.vii / Chapter 1 --- p.1 / Introduction --- p.1 / Chapter 1.1 --- Mesenchymal stem cells --- p.2 / Chapter 1.1.1 --- Characteristics of mesenchymal stem cells --- p.2 / Chapter 1.1.2 --- Bone marrow- and peripheral blood-derived MSCs --- p.4 / Chapter 1.1.3 --- Other tissue-derived MSCs --- p.5 / Chapter 1.2 --- Adipogenesis of MSCs --- p.6 / Chapter 1.3 --- Chondrogenesis of MSCs --- p.7 / Chapter 1.4 --- Osteogenesis of MSCs --- p.8 / Chapter 1.4.1 --- Regulators of osteogenesis --- p.9 / Chapter 1.4.2 --- Stratergies for improving bone tissue engineering --- p.11 / Chapter 1.5 --- Signaling pathways involved in osteogenesis --- p.13 / Chapter 1.5.1 --- ERK signaling pathway --- p.14 / Chapter 1.5.2 --- Wnt signaling pathway --- p.15 / Chapter 1.5.3 --- BMP signaling pathway --- p.17 / Chapter 1.6 --- Migration of MSCs --- p.20 / Chapter 1.7 --- Fracture healing --- p.22 / Chapter 1.8 --- Clinical application of MSCs --- p.23 / Chapter 1.8.1 --- BM-MSCs vs. PB-MSCs --- p.24 / Chapter 1.8.2 --- Autologous vs. Allogeneic MSCs transplantation --- p.25 / Chapter 1.9 --- Scope of the present study --- p.26 / Chapter 1.9.1 --- CRBP1 --- p.26 / Chapter 1.9.2 --- N-cadherin --- p.27 / Chapter 1.9.3 --- SOX11 --- p.27 / Chapter 1.10 --- Experimental scheme --- p.29 / Chapter 2 --- p.31 / Comparison between PB-MSCs and BM-MSCs --- p.31 / Chapter 2.1 --- Chapter introduction --- p.32 / Chapter 2.2 --- Materials and methods --- p.33 / Chapter 2.2.1 --- Cell culture --- p.33 / Chapter 2.2.2 --- Flow cytometry --- p.33 / Chapter 2.2.3 --- Adipogenic differentiation --- p.34 / Chapter 2.2.4 --- Osteogenic differentiation --- p.34 / Chapter 2.2.5 --- RNA Extraction and Real-time PCR --- p.34 / Chapter 2.3 --- Results --- p.35 / Chapter 2.3.1 --- Morphology of PB-MSCs --- p.35 / Chapter 2.3.2 --- Cellular surface markers of BM-MSCs and PB-MSCs --- p.36 / Chapter 2.3.3 --- Multi-differentiation potential of BM-MSCs and PB-MSCs --- p.38 / Chapter 2.3.4 --- Target genes expression in BM-MSCs and PB-MSCs --- p.39 / Chapter 2.4 --- Discussion and future work --- p.40 / Chapter 3 --- p.41 / Role of CRBP1 in Differentiation and Migration of MSCs --- p.41 / Chapter 3.1 --- Chapter introduction --- p.42 / Chapter 3.2 --- Materials and methods --- p.46 / Chapter 3.2.1 --- Chemicals --- p.46 / Chapter 3.2.2 --- Isolation and culture of BM-MSCs --- p.46 / Chapter 3.2.3 --- RNA Extraction and Real-time PCR --- p.47 / Chapter 3.2.4 --- Plasmid construction, transfection, production of lentivirus and infection --- p.48 / Chapter 3.2.5 --- Osteogenic differentiation --- p.50 / Chapter 3.2.6 --- Adipogenic differentiation --- p.50 / Chapter 3.2.7 --- Western blot --- p.51 / Chapter 3.2.8 --- Immunofluorescence labeling and fluorescence microscopy --- p.52 / Chapter 3.2.9 --- Cell migration assay --- p.52 / Chapter 3.2.10 --- Ectopic bone formation assay --- p.52 / Chapter 3.2.11 --- Statistical analysis --- p.53 / Chapter 3.3 --- Results --- p.53 / Chapter 3.3.1 --- Transducing BM-MSCs with lentivirus carrying CRBP1 or shRNAs --- p.53 / Chapter 3.3.2 --- CRBP1 accelerates osteogenesis of BM-MSCs via enhancing ERK1/2 and β-catenin pathways --- p.56 / Chapter 3.3.3 --- CRBP1 stabilizes β-catenin by inhibiting RXRα-induced degradation --- p.58 / Chapter 3.3.4 --- CRBP1 inhibits adipogenesis of BM-MSCs --- p.61 / Chapter 3.3.5 --- CRBP1 overexpression has no effect on MSCs migration potential --- p.63 / Chapter 3.3.6 --- CRBP1 promotes ectopic bone formation in vivo --- p.64 / Chapter 3.4 --- Discussion --- p.66 / Chapter 3.5 --- Future work --- p.73 / Chapter 4 --- p.74 / Role of N-cadherin in Differentiation and Migration of MSCs --- p.74 / Chapter 4.1 --- Chapter introduction --- p.75 / Chapter 4.2 --- Materials and methods --- p.78 / Chapter 4.2.1 --- Chemicals --- p.78 / Chapter 4.2.2 --- Isolation and culture of BM-MSCs --- p.78 / Chapter 4.2.3 --- Plasmid construction, transfection, production of lentivirus and infection --- p.79 / Chapter 4.2.4 --- Osteogenic differentiation and ALP activity assay --- p.81 / Chapter 4.2.5 --- Western blot --- p.81 / Chapter 4.2.6 --- Ectopic bone formation assay --- p.82 / Chapter 4.2.7 --- Statistical analysis --- p.82 / Chapter 4.3 --- Results --- p.83 / Chapter 4.3.1 --- Expression of N-cadherin during osteogenesis in MSCs --- p.83 / Chapter 4.3.2 --- N-cadherin overexpression inhibits osteogenesis through suppressing β-catein and ERK1/2 signaling pathways --- p.84 / Chapter 4.3.3 --- N-cadherin silencing increases osteogenesis through enhancing β-catenin and ERK1/2 signaling pathways --- p.86 / Chapter 4.3.4 --- N-cadherin promotes migration of MSCs --- p.87 / Chapter 4.3.5 --- Cellular surface markers of SV40-immortalized MSCs --- p.89 / Chapter 4.3.6 --- N-cadherin inhibits ectopic bone formation in vivo --- p.89 / Chapter 4.4 --- Discussion --- p.91 / Chapter 4.5 --- Future work --- p.94 / Chapter 5 --- p.96 / Role of SOX11 in Differentiation and Migration of MSCs --- p.96 / Chapter 5.1 --- Chapter introduction --- p.97 / Chapter 5.2 --- Materials and methods --- p.105 / Chapter 5.2.1 --- Plasmid construction, transfection, production of lentivirus and infection --- p.105 / Chapter 5.2.2 --- Cell culture --- p.106 / Chapter 5.2.3 --- Luciferase reporter gene assay --- p.106 / Chapter 5.2.4 --- Osteogenic differentiation and ALP activity assay --- p.106 / Chapter 5.2.5 --- Adipogenic differentiation --- p.107 / Chapter 5.2.5 --- Chondrogenic diffferentiation --- p.107 / Chapter 5.2.6 --- Western blot --- p.108 / Chapter 5.2.7 --- RNA Extraction and Real-time PCR --- p.108 / Chapter 5.2.8 --- Cell migration --- p.110 / Chapter 5.2.9 --- Ectopic bone formation --- p.110 / Chapter 5.2.10 --- Fracture healing model and analysis --- p.111 / Chapter 5.2.11 --- Statistical Analysis --- p.112 / Chapter 5.3 --- Results --- p.112 / Chapter 5.3.1 --- SOX11 is upregulated during osteogenesis of BM-MSCs --- p.112 / Chapter 5.3.2 --- SOX11 promotes adipogenesis in BM-MSCs --- p.113 / Chapter 5.3.3 --- SOX11 promotes migration of BM-MSCs --- p.114 / Chapter 5.3.4 --- SOX11 promotes osteogenesis in BM-MSCs --- p.115 / Chapter 5.3.5 --- SOX11 promotes chondrogenesis of MSCs --- p.117 / Chapter 5.3.6 --- Mechanisms of how SOX11 regulates differentiation and migration of MSCs --- p.118 / Chapter 5.3.7 --- SOX11-modified MSCs promote bone fracture healing in an open femur fracture rat model --- p.122 / Chapter 5.4 --- Discussion --- p.126 / Chapter 5.5 --- Future work --- p.131 / Appendix --- p.153
22

Consequences of in vitro and in vivo environmental cues on localized delivery of MSCs

Burand Jr., Anthony John 01 January 2019 (has links)
Mesenchymal stromal cells (MSCs) are being explored for treatment of inflammatory, ischemic, autoimmune, and degenerative diseases. More and more of these diseases require MSCs to be delivered locally to the diseased site rather than systemically injected into patients. However, little is understood about whether cell cryopreservation or prelicensing will affect the efficacy of the locally injected product or how the local injection environment affects MSC expression of trophic factors and interactions with patient immune cells. Several groups have disagreed on whether cryopreservation hinders MSC potency and therefore it is important to understand the effects of cryopreservation on MSC function and in what contexts cryopreservation can be used. Therefore, a better understanding of MSC phenotype after local injection is needed so that cryopreservation and prelicensing can be optimized to modulate cell potency for more efficacious MSC products. Currently, it has been shown that in vivo there are rapid drastic shifts in gene expression by MSCs which have been locally injected. One of the most prominent gene changes is in the enzyme COX-2 which leads to the production of bioactive lipids called prostaglandins, namely PGE2. PGE2 has several functions depending on the context in which other cells encounter it. In order to model the gene changes that occur in vivo, in vitro cell aggregates termed spheroids have been utilized to study the effects of local injection of MSCs. MSC spheroids have shown more potency than their 2D counterparts in shifting macrophage polarization and rescue of cells from ischemic damage. This thesis examines how process variables like cryopreservation and prelicensing affect the efficacy of the MSC product in the context of local injection. Additionally, it shows how spheroid formation alters therapeutic factor expression and activity and how drug treatment and biomaterials can be utilized to modify potency of these cells. In Chapter 2, we demonstrate that cryopreservation in the context of an ischemia/reperfusion injury in the eye does not significantly decrease MSCs effectiveness in salvaging neuronal cells. However, IFN-γ, a commonly used prelicensing cytokine to increase MSC potency, led to a decrease in the effectiveness of MSCs in this model. Chapters 3 and 4 define the changes that occur to several of MSCs’ trophic factors including immunomodulatory and growth factors and how these alterations affect MSC interactions with macrophages and T cells. Because validation and tracking of locally injected products can be cost-prohibitive for many research groups, Chapter 5 lays out a low-cost method to track fluorescently labeled cells in local injections to skin to aid in minimization of variability in results obtained from animal wound healing models. These findings demonstrate that initial preparation of MSC therapeutics is critical to their efficacy in local injection. Therefore, careful testing of potency for large-scale MSC production pipelines should be evaluated to ensure the efficacy of the resulting product. Additionally, spheroids exhibit differences in the mechanisms of action due to alterations in their secretome which can be partly overcome with co-administration of steroids such as budesonide. Therefore, steroid co-administration with MSCs being considered for local application should be further explored for use in local delivery of MSCs for the treatment of inflammatory conditions. Finally, this research demonstrates the need to further understand the mechanisms by which spheroids alter their gene and trophic factor production to better tailor MSC therapies for disease specific localized injection.
23

The bone marrow microenvironment in myelodysplastic syndromes : functional and molecular study / Le microenvironnement médullaire au cours des syndromes myélodysplasiques : étude fonctionnelle et moléculaire

Goulard, Marie 28 September 2017 (has links)
Les syndromes myélodysplasiques (MDS) sont un groupe de pathologies myéloïdes caractérisées par une hématopoïèse inefficace. Le rôle du microenvironnement médullaire (MM) dans l’histoire naturelle de ces pathologies reste incertain. Des anomalies du MM ont été décrites au cours des myélodysplasies et des modèles murins récemment publiés font penser qu’une altération du MM pourrait jouer un rôle dans le déclenchement et/ou l’évolution de ces maladies.Nous avons tenté de développer un modèle in vivo récapitulant l’histoire naturelle des myélodysplasies par des xénogreffes chez des souris NSG et NSG-S. Le faible taux de prise de greffe nous a amenés à développer un modèle in vitro de co-culture en 2D. Ce modèle est une bonne alternative pour les études de nouvelles stratégies thérapeutiques pour les patients atteints de myélodysplasies.Au cours de ce travail, nous avons également réalisé une étude systématique du stroma médullaire de patients atteints de syndromes myélodysplasiques dans le but d’identifier les anomalies fonctionnelles et moléculaires des cellules souches mésenchymateuses (CSMs), cellules centrales du MM pour leur interaction avec les cellules souches hématopoïétiques (CSHs).Les CSMs de MDS ont une clonogénécité diminuée. Nous n’avons pas observé de modification significative de leurs capacités de différenciation en ostéoblastes, adipocytes et chondrocytes ni dans leur capacité à supporter une hématopoïèse normale. Les CSMs de MDS présentent des modifications au niveau épigénétique et transcriptionnel pouvant expliquer l’altération des relations observées grâce à de l’imagerie enregistrée entre les CSMs de MDS et les CSHs dans un modèle de co-culture en 3D.Ces résultats montrent que les CSMs de MDS ont des modifications fonctionnelles et moléculaires et que ces anomalies perturbent leur relation avec les CSHs. / Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal myeloid pathologies characterized by an impaired hematopoiesis. The role of the bone marrow microenvironment (BMM) remains unclear in the natural history of these diseases. Abnormalities of the BMM have been observed in myelodysplasia and a recent published murine model implies that alterations of the BMM could play a role in the trigger/progression of these diseases.Firstly, we tried to develop an in vivo model of MDS in NSG and NSG-S mice. The low rate of engraftment pushed us to develop a 2D co-culture model in vitro. This model is a good alternative to test new therapeutic strategies for MDS patients.In this study, we analysed mesenchymal stromal cells (MSCs) from the bone marrow of pretreated MDS patients in order to identify the functional and molecular abnormalities in those cells of the BMM, central for their interactions with the hematopoietic stem cells (HSCs).MDS MSCs have an impaired clonogenic capacity. We didn’t observed modifications of their differentiation toward osteogenic, adipogenic and chondrogenic pathways and capacity to support of a normal hematopoiesis. MDS MSCs display epigenetic and transcriptomic modifications that could explain the alteration of the relationships between these cells and HSCs observed in imagery in a 3D co-culture model.These results showed that MDS MSCs have functional and molecular abnormalities and that these alterations could impair their relationship with HSCs.
24

Formation of Composite Islet Grafts : A novel strategy to promote islet survival and revascularization

Johansson, Ulrika January 2009 (has links)
The islets of Langerhans are small and delicate spheroid organs scattered in the pancreas responsible for insulin production. Transplantation of isolated islets is a beneficial therapy for patients with a severe form of type 1 diabetes. The islets, which normally are richly vascularized in the pancreas, are completely disconnected from the vascular support by the enzymatic digestion during the isolation procedure. Islet viability is affected throughout all steps in this process, from donor death and isolation of islets to culturing and the transplantation process itself. In this thesis a novel strategy to promote islet survival and to re-establish islet vasculature is presented. We show endogenous expression of 51 different genes related to inflammation in cultured islets. Among these genes high expression of MCP-1, MIF, VEGF, thymosin b-10 and IL-8, IL-1β, IL-5R-a, IFN-γ antagonist were found in all donors during the 5- and the 2-day cultures, respectively. Protein expression of these genes can stimulate inflammatory immune responses but also promote tissue repair by attracting curative cells such as endothelial cells (EC) leading to re-establishment of the vasculature. We have established a novel technique by formation of composite islets using EC and mesenchymal stem cells (MSC). EC adhered on the surface of the islets and created a potential blood tolerant surface. The EC-islets showed a degree of protection from the detrimental effects of instant blood-mediated inflammatory reaction (IBMIR) with the major components of IBMIR being decreased in in vitro assays. We combined MSC to the EC-islets with success. The MSC were found to have proliferative effect on EC and the combination of these two cell types on the islets further increased the EC covered surface compared to EC-islets. The EC-MSC-islets in co-culture formed vessel-like structures both into the islets and out to the surrounding matrix. The MSC enhanced the exogenous EC to form vessel-like network in the EC-MSC-islets indicating vascular support by the MSC. The novel strategy and conditions presented herein could alleviate problems related to survival of the islets by promoting revascularization. This would open up a new era in islet transplantation and allow more patients to benefit from this therapy. / Clinical immunology, islet group
25

Mesenchymal stromal cells of human umbilical cord Wharton's jelly accelerate wound healing by paracrine mechanisms

Ueda, Minoru, Kikkawa, Fumitaka, Hibi, Hideharu, Iwase, Akira, Takikawa, Sachiko, Yamamoto, Akihito, Shohara, Ryutaro 09 1900 (has links)
名古屋大学博士学位論文 学位の種類 : 博士(医学)(課程) 学位授与年月日:平成25年1月31日 匠原龍太郎氏の博士論文として提出された
26

Characterization of Genetically Modified HUCPVCs as an Osteogenic Cell Source.

Estrada-Vallejo, Catalina 09 January 2014 (has links)
Tissue engineering and ex vivo gene therapy can be used synergically as tool to regenerate bone, which overcome the problems of currently available bone replacements. Recently, a new source of mesenchymal stromal cells (MSCs) has been found in the umbilical cord; human umbilical cord perivascular cells (HUCPVCs) provide an alternative to bone marrow derived MSCs and due to their easy harvest, fast expansion, and non-immunogeneic and immunomodulatory phenotype we hypothesized that HUCPVCs are a putative candidate cell source for osteogenic ex vivo gene therapy. This work proposes the generation of cocktails of genetically modified HUCPVCs and their cryopreservation as an “off the shelf” therapeutic. This approach involves the engineering of osteogenic cell populations, by genetically modifying HUCPVCs using recombinant adenoviruses to deliver four fundamental genes for bone formation: bone morphogenetic protein 2 (BMP-2), runt-related transcription factor 2 (Runx2), Osterix (OSX/SP7) transcription factor and vascular endothelial growth factor (VEGF). Our results show that HUCPVCs can be efficiently modified by adenoviruses and can be cryopreserved without affecting the production efficiency and bioactivity of proteins of interest produced by the cells. Moreover, overexpression of BMP2, Runx2 and SP7 enhances ALP activity levels in HUCPVCs and upregulates ALP, OPN, COL1A1 and OCN gene expression; data that provides the first evidence of the effects of combinational expression of BMP2, Runx2 and SP7. Furthermore, we report for the first time the genetic modification of human BMSCs to express SP7 and Runx2, which enhances their ALP activity and matrix mineralization capacity.
27

Characterization of Genetically Modified HUCPVCs as an Osteogenic Cell Source.

Estrada-Vallejo, Catalina 09 January 2014 (has links)
Tissue engineering and ex vivo gene therapy can be used synergically as tool to regenerate bone, which overcome the problems of currently available bone replacements. Recently, a new source of mesenchymal stromal cells (MSCs) has been found in the umbilical cord; human umbilical cord perivascular cells (HUCPVCs) provide an alternative to bone marrow derived MSCs and due to their easy harvest, fast expansion, and non-immunogeneic and immunomodulatory phenotype we hypothesized that HUCPVCs are a putative candidate cell source for osteogenic ex vivo gene therapy. This work proposes the generation of cocktails of genetically modified HUCPVCs and their cryopreservation as an “off the shelf” therapeutic. This approach involves the engineering of osteogenic cell populations, by genetically modifying HUCPVCs using recombinant adenoviruses to deliver four fundamental genes for bone formation: bone morphogenetic protein 2 (BMP-2), runt-related transcription factor 2 (Runx2), Osterix (OSX/SP7) transcription factor and vascular endothelial growth factor (VEGF). Our results show that HUCPVCs can be efficiently modified by adenoviruses and can be cryopreserved without affecting the production efficiency and bioactivity of proteins of interest produced by the cells. Moreover, overexpression of BMP2, Runx2 and SP7 enhances ALP activity levels in HUCPVCs and upregulates ALP, OPN, COL1A1 and OCN gene expression; data that provides the first evidence of the effects of combinational expression of BMP2, Runx2 and SP7. Furthermore, we report for the first time the genetic modification of human BMSCs to express SP7 and Runx2, which enhances their ALP activity and matrix mineralization capacity.
28

Administration of adipose-derived stromal vascular fraction and platelet rich plasma in dogs with coxofemoral osteoarthritis

Upchurch, David A. January 1900 (has links)
Master of Science / Department of Clinical Sciences / Walter Renberg / Objective: To evaluate the safety and effect of a single simultaneous intra-articular and intravenous injection of autologous adipose-derived stromal vascular fraction (SVF) and platelet rich plasma (PRP) on coxofemoral osteoarthritis (OA) in dogs. Methods: This was a randomized, double-blind, placebo-controlled prospective pilot trial of simultaneous intra-articular and intravenous SVF and PRP for coxofemoral OA. Dogs with coxofemoral OA causing signs of lameness or discomfort were evaluated by orthopedic exam, visual lameness score, Canine Brief Pain Inventory (CBPI), goniometry, visual analogue scale (VAS), and pressure-sensitive walkway (PSW) at week 0 (baseline), and at 4, 8, 12 and 24 weeks after injection. Joint radiographs were scored at 0 and 24 weeks. Results: Twenty two client-owned dogs with naturally occurring OA of the coxofemoral joints were enrolled (12 placebo-control, 10 SVF-treated). CBPI pain severity scores were lower in the treatment group at 24 weeks compared to the placebo group (p=0.042). The VAS score for the treatment group was significantly greater at 0 weeks than at 4, 8, or 24 weeks (p<0.05). When dogs with low quartile baseline PVF (25th percentile) were compared, the treatment group had statistically higher PVF at all post-injection time points when compared to the placebo group. After SVF injection, fewer dogs in the treated group were lame compared to the control group. Clinical Significance: This study is the first to utilize objective data from PSW as an outcome measure for dogs treated with SVF and PRP for coxofemoral OA. No adverse events were noted. Improvements in some measured parameters in the treated dogs compared to those in the placebo group.
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Avaliação do potencial terapêutico de pericitos e de células mesenquimais no camundongo SOD1, modelo animal para esclerose lateral amiotrófica / Evaluation of the therapeutic potential of pericytes and mesenchymal stromal cells in SOD1 mice, animal model for amyotrophic lateral sclerosis

Giuliana Castello Coatti 14 August 2015 (has links)
A Esclerose Lateral Amiotrófica (ELA), também conhecida como Doença de Lou Gehrig, é a forma mais comum de doença do neurônio motor. Tem início geralmente tardio (4ª/5ª década de vida), afetando tanto os neurônios motores superiores quanto os inferiores. A degeneração provocada pela ELA é progressiva e irreversível. Em geral, a evolução da doença é rápida, levando os pacientes ao óbito entre 3 e 5 anos após o início dos sintomas, devido principalmente à falência respiratória. Atualmente, o único medicamento liberado pelo FDA (Food and Drug Administration) para o uso em ELA é o Riluzol, que tem um efeito mínimo na expectativa de vida dos pacientes. Neste cenário, a terapia celular vem sendo avaliada como uma possível alternativa. Estudos pré-clínicos indicam efeitos benéficos do tratamento de camundongos SOD1 (modelo animal para ELA) com células estromais mesenquimais ou simplesmente células mesenquimais (MSCs), atribuída principalmente à ação de fatores solúveis. Aqui propusemos o uso de pericitos, uma linhagem celular ainda não testada para tratamento pré-clinico em modelo murinho de ELA. Pericitos são células perivasculares que circundam células endoteliais e que desempenham importantes funções celulares como por exemplo participação da formação e manutenção da barreira hematoencefálica, essencial para proteger o sistema nervoso central de danos em doenças neurodegenerativas. Dessa forma, este trabalho pretendeu comparar o potencial terapêutico de células mesenquimais e pericitos obtidos do tecido adiposo humano de um mesmo doador, em camundongos SOD1. Para tal, testes físicos (peso, PaGE, motor score, rotarod) foram aplicados semanalmente e a sobrevida dos animais foi avaliada. Os resultados demonstram que, com exceção dos benefícios observados nos testes do PaGE e do motor score em uma fase mais inicial da doença, o tratamento com MSCs ou pericitos não resulta em efeitos significativos no quadro clínico de camundongos SOD1 do sexo feminino. Para os machos, o tratamento com pericitos se destaca em relação aos tratamentos com MSCs ou HBSS (veículo), resultando em efeitos benéficos na sobrevida e em determinadas funções motoras dos animais, com destaque para os testes do motor score e do rotarod, onde há uma melhora na fase inicial da doença. A análise da expressão gênica no cérebro e na medula de animais em fase final da doença sugere que o tratamento de machos com pericitos é capaz de estimular as defesas antioxidantes do animal. Ainda nestes órgãos, não foram encontrados vestígios das células humanas injetadas, indicando um possível efeito sistêmico das mesmas / Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig\'s disease, is the most common form of motor neuron disease. Most cases are characterized by an adult onset of symptoms, usually in the fourth or fifth decade of life, affecting both upper and lower motor neurons. The degeneration caused by ALS is progressive and irreversible. On average, the survival ranges from 3 to 5 years after onset, mainly due to respiratory failure. Currently, the only Food and Drug Administration (FDA)-approved medication for this disorder is Riluzole, but its effects on survival are minimal. In this scenario, cell therapy is being evaluated as a possible alternative. Preclinical studies indicate beneficial effects of treatment of SOD1 mice (animal model for ALS) with mesenchymal stromal cells or simply mesenchymal cells (MSCs), mainly attributed to the action of soluble factors. Here we propose the use of pericytes, a cell line not yet tested for preclinical treatment in of ALS. Pericytes are perivascular cells surrounding endothelial cells and play important cellular roles such as assistance of formation and maintenance of the blood-brain barrier, which is essential to protect the central nervous system from damage in neurodegenerative diseases. Thus, this study sought to compare the therapeutic potential of mesenchymal cells and pericytes, both obtained from the same human adipose tissue, in SOD1 mice. For this purpose, survival and physical performance (weight, PaGE, motor score and rotarod) were evaluated. Except for the benefits observed in PaGE and the motor score tests in an early stage of the disease, treatment with MSCs and pericytes does not result in significant effects on disease progression of SOD1 female mice. For males, treatment with pericytes stands out compared to treatment with MSCs or HBSS (vehicle), resulting in beneficial effects on survival and in certain physical functions of the animals, particularly for the motor score and rotarod tests, where improvement was observed in the initial stage of the disease. The analysis of gene expression in the brain and spinal cord in end-stage animals suggests that treatment of males with pericytes can stimulate the animals\' antioxidant defense. No traces of injected human cells were observed in brain or spinal cord of mice, indicating a possible systemic effect of the transplant
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Caracterização do secretoma de células multipotentes mesenquimais estromais de diferentes fontes / Characterization of the secretome of multipotent mesenchymal stromal cells from various tissues

Amanda Faria Assoni 11 September 2015 (has links)
Células multipotentes mesenquimais estromais (CTM) são células adultas multipotentes que podem ser isoladas a partir de diferentes tecidos e são capazes de atingir sítios danificados, exercer papéis na regeneração tecidual e modular a resposta imune. Estas células demonstraram resultados discrepantes em estudos in vivo dependentes de sua fonte de obtenção. Há na literatura hipóteses de que o mecanismo predominante pelo qual as CTMs atuam no reparo tecidual estaria relacionado à sua atividade parácrina, criando um microambiente com sinais tróficos. Nesse sentido, a avaliação do conteúdo do secretoma destas células é de grande interesse. Portanto, este projeto teve como objetivo analisar o meio condicionado de CTMs obtidas de diferentes fontes (tecido adiposo, músculo esquelético e tubas uterinas) de mesmos indivíduos. A abordagem experimental consistiu em proteômica shotgun (nanocromatografia líquida acoplada a espectrometria de massas em tandem) com o intuito de identificar alvos diferentemente expressos entre as culturas que possam sugerir funções específicas de cada linhagem celular. Os dados espectrais foram obtidos pelo modo de aquisição dependente de dados (Top15). Os dados adquiridos foram processados pelas plataformas MaxQuant e TPP (Trans-Proteomic Pipeline). Foi realizada análise qualitativa de vias enriquecidas por meio do programa Ingenuity utilizando as proteínas em comum nos secretoma de todas as CTMs analisadas. Essa análise permitiu observar vias enriquecidas de proliferação celular, migração celular e desenvolvimento do sistema cardiovascular, demonstrando que as proteínas secretadas por quaisquer das CTMs analisadas podem ser relacionadas a resultados encontrados na literatura utilizando estas células para terapias para patologias. As análises estatísticas para determinar se haveria dependência da composição do secretoma em função do indivíduo doador ou tecido fonte das CTMs revelaram proteínas diferencialmente expressas entre todos os grupos. Estas proteínas diferencialmente expressas são relacionadas à proliferação, sinalização e interação celular, além de modulação do sistema imune e da angiogênese. Neste contexto, podemos concluir que o secretoma das CTMs é muito semelhante, que as CTMs isoladas de quaisquer tecidos ou indivíduos são capazes de secretar moléculas que possivelmente exercem benefícios em determinado tratamento. Entretanto, estes benefícios podem ser exacerbados ou suprimidos pelas moléculas diferencialmente expressas, as quais são dependentes tanto dos tecidos quanto dos indivíduos dos quais as CTMs foram obtidas / Multipotent Mesenchymal Stromal Cells (MSCs) are multipotent adult cells that can be isolated from different tissues and are able to reach damaged sites, play a role in tissue regeneration and modulate immune response. These cells showed conflicting results in studies in vivo depending on their tissue origin. It is hypothesised that the predominant mechanism by which MSCs function could be related to its paracrine activity, creating a microenvironment with trophic signals. Accordingly, the evaluation of the content of the secretome of these cells is of great interest. Towards this end, this project analyzed the proteins of conditioned medium of MSCs obtained from different sources from the same donors (adipose tissue, uterine tubes and skeletal muscle). The MSCs were characterized by flow cytometry for the presence of membrane markers and by differentiation in vitro into adipocytes, chondrocytes, and osteoblasts. The conditioned media were obtained and the protein profile was analysed by liquid nanochromatography coupled to tandem mass spectrometry. Spectral data were obtained by full-acquisition mode MS / dd-MS2 (Top15). The acquired data were processed by MaxQuant software and TPP (Trans-Proteomic Pipeline). Qualitative analysis of enriched pathways through the Ingenuity program using the shared proteins between the cell lineages was performed.It showed enriched pathways related to cell proliferation, cell migration and development of the cardiovascular system. This allows considering that the secreted proteins from the analyzed MSCs might be related to findings in the literature using these cells for therapies. After this, the proteins were analyzed for differential expression by comparing the MSCs into groups of different sources or different donors. In which were observed differentially expressed proteins related to proliferation, cell signaling and interaction, modulation of the immune system and angiogenesis. In this context, we can conclude that MSC\'s secretome is very similar in the analyzed lineages, and that any MSCs are able to secrete molecules which potentially exert for certain treatment benefits. However, these benefits can be exacerbated or annulled by differentially expressed molecules, which are dependent both as the individual and tissues from which MSCs were obtained

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