In March 2006, murine Bone Marrow Stromal Cells (BMSC) were flown in the Soyuz 12S to the International Space Station to investigate the effects of microgravity on their osteogenic potential in a three-dimensional environment. BMSC were grown in porous bioceramic Skelite disks ( 9 mm x T 1.2 mm). The constructs were exposed to microgravity for ca. 8 days, then fixed for RNA extraction. While the flight experiment was performed in fully automated hardware inside the KUBIK incubator, one group of control samples were incubated inside manually operated hardwares (flight control), and the other control group was incubated under routine laboratory conditions (lab control). The altered gene expression profile was analyzed by Mouse Gene 1.0 ST array (Affymetrix) representing whole-transcript coverage. Each one of the 28853 genes is represented on the array by approximately 26 probes spread across the full length of the gene, providing a more complete and more accurate picture of gene expression than the 3 based expression array design.
Activation of nervous system development genes in bone marrow derived mesenchymal stem cells following spaceflight exposure.
Specimen part, Disease
View SamplesEGR3 expression is upregulated in human prostate cancer compared to normal prostate tissue and is associated with absence of relapse, while low EGR3 expression in tumors is predicitive of disease relapse (Pio et al., PLOS One 2013; 8(1):e54096). However the function of EGR3 in prostate cancer is unknown. Human prostate cancer cells M12 containing high levels of EGR3 were used for shRNA-mediated silencing of EGR3. Gene expression analysis of EGR3 knockdown cells reveals a role in inflammation and the existence of a crosstalk with the NFkB pathway.
Early growth response 3 (Egr3) is highly over-expressed in non-relapsing prostate cancer but not in relapsing prostate cancer.
Cell line, Treatment
View SamplesStem and progenitor cells are the critical units for tissue maintenance, regeneration, and repair. The activation of regenerative events in response to tissue injury has been correlated with mobilization of tissue-resident progenitor cells, which is functional to the wound healing process. However, until now there has been no evidence for the presence of cells with a healing capacity circulating in healthy conditions. We identified a rare cell population present in the peripheral blood of healthy mice that actively participates in tissue repair. These Circulating cells, with a Homing ability and involved in the Healing process (CH cells), were identified by an innovative flowcytometry strategy as small cells not expressing CD45 and lineage markers. Their transcriptome profile revealed that CH cells are unique and present a high expression of key pluripotency- and epiblast-associated genes. More importantly, CH-labeled cells derived from healthy Red Fluorescent Protein (RFP)-transgenic mice and systemically injected into syngeneic fractured wild-type mice migrated and engrafted in wounded tissues, ultimately differentiating into tissue-specific cells. Accordingly, the number of CH cells in the peripheral blood rapidly decreased following femoral fracture. These findings uncover the existence of constitutively circulating cells that may represent novel, accessible, and versatile effectors of therapeutic tissue regeneration.
Identification of a New Cell Population Constitutively Circulating in Healthy Conditions and Endowed with a Homing Ability Toward Injured Sites.
Sex, Specimen part
View SamplesThe classical concept of bone marrow-derived mesenchymal stem cells (BM-MSC), intended as a uniform, broad potent population, is progressively being substituted by the idea that the bone marrow harbors heterogeneous populations of non-hematopoietic stem cells. This in vivo heterogeneity is also amplified by the different experimental strategies used to isolate/culture them. Among the exogenous factors described to affect MSC in vitro growth, basic-fibroblast growth factor (bFGF) is one of the most common growth factors used to expand stem cells. Moreover, it has been reported that its signaling is associated with the mainteinance of stemness of a variety of stem cells, included MSC. Using an ectopic model of bone regeneration, we have previously described that the implantation of cells with different commitment levels, differentially influences the capacity to recruit host cells, activating endogenous regenerative mechanisms. Due to its properties, we here demonstrate that the addition of bFGF to primary BM cultures, leads to the selection of specific subpopulations able to induce a different host regenerative response, when in vivo implanted in association with suitable ceramic scaffolds. Moreover, taking advantage of a multiparametric and comparative genomic and proteomic approach, it has been evaluated how different culture conditions combine to bring about appreciable changes in the secretome of the cells, that consequently influence their in vivo regenerative behaviour. The full comprehension of the regulatory mechanisms that rule the host response depending on the type and differentiative stage of the transplanted cells could help us to develop novel clinical strategies where host cells could directly contribute to regenerate the appropriate tissue.
The role of bFGF on the ability of MSC to activate endogenous regenerative mechanisms in an ectopic bone formation model.
Specimen part, Disease
View SamplesThe anthracycline, doxorubicin (Dox), is widely used in oncology, but it may it may cause a cardiomyopathy which has dismal prognosis and cannot be effectively prevented. The secretome of multipotent human amniotic fluid-derived stem cells (hAFS) has previously been demonstrated to reduce ischemic cardiac damage. Here, it is shown that the hAFS conditioned medium (hAFS-CM) antagonizes senescence and apoptosis of cardiomyocytes and cardiac progenitor cells, two major features of Dox cardiotoxicity. Mechanistic studies with primary mouse neonatal cardiomyocytes reveal that hAFS-CM inhibition of Dox-elicited senescence and apoptosis is paralleled by decreased DNA damage and is associated with nuclear translocation of NF-kB and upregulation of a set of genes controlled by NF-kB, namely Il6 and Cxcl1, which promote cardiomyocyte survival, and Cyp1b1 and Abcb1, which encode for proteins involved in Dox metabolism and efflux, respectively. The PI3K/Akt signaling cascade, upstream of NF-kB, is potently activated by the hAFS-CM and pre-treatment with a PI3K inhibitor abrogates NF-kB accumulation into the nucleus, modulation of its target genes, and prevention of Dox-initiated senescence and apoptosis in response to the hAFS-CM. This work may lay the ground for the development of a stem cell-based paracrine therapy of chemotherapy-related cardiotoxicity.
The human amniotic fluid stem cell secretome effectively counteracts doxorubicin-induced cardiotoxicity.
Specimen part
View SamplesFocal adhesion kinase (FAK) is a non-receptor tyrosine kinase that plays an important role in proliferation, motility, adhesion, invasion, angiogenesis, and survival signaling. Focal adhesion kinase has been shown to be overexpressed in many types of tumors, including breast cancer at early stages of tumorigenesis. To study the biological role of FAK in breast tumorigenesis, we used FAKsiRNA to down-regulate FAK in MCF-7 cell lines.
The direct effect of focal adhesion kinase (FAK), dominant-negative FAK, FAK-CD and FAK siRNA on gene expression and human MCF-7 breast cancer cell tumorigenesis.
No sample metadata fields
View SamplesThe origin and nature of recently discovered age-associated B cells (ABCs) is under investigation.
Age-Associated B Cells Express a Diverse Repertoire of V<sub>H</sub> and Vκ Genes with Somatic Hypermutation.
Sex, Age, Specimen part
View SamplesIn order to study the microglia contribution in neurodegeneration more specifically we established a mouse model of prion disease in which the 79A murine prion strain was introduced by an intraperitoneal route into BALB/cJFms-EGFP/- mice, which express Enhanced Green Fluorescent Protein (EGFP) under control of the C-fms operon. Samples were taken at time points during disease progression and histological analysis of the brain and transcriptional analysis of isolated microglia was carried out. The analysis of isolated microglia revealed a disease specific, highly pro-inflammatory signature in addition to an up-regulation of genes associated with metabolism, respiratory stress and DNA repair. This study strongly supports the growing recognition of the importance of microglia within the prion disease process and identifies the nature of the response through gene expression analysis of isolated microglia.
Defining the Microglia Response during the Time Course of Chronic Neurodegeneration.
Sex, Specimen part
View SamplesMLL-AF9 expression in normal human umbilical cord blood CD34+ cells leads to long-term proliferation of a myeloid progenitor cell with leukemogenic potential. Expression of a Core Binding Factor leukemia fusion (AML1-ETO or CBFbeta-SMMHC) in human CD34+ cells results in self-renewal of primitive progenitor cells with multilineage potential and stem cell ability, but these cells do not induce leukemia in immunodeficient mice. This comparative microarray study was initiated to determine how faithful these cell cultures are to the transcriptome of patient samples expressing each of these different fusion proteins, and to analyze the signaling pathways that are unique to CBF cultures and MLL-fusion cultures, with the hope of determining why the MLL-fusion cells are leukemogenic while the CBF cells are not.
Microenvironment determines lineage fate in a human model of MLL-AF9 leukemia.
No sample metadata fields
View SamplesThe Kruppel-like factor 5 (Klf5) regulates pluripotent stem cell self-renewal but its role in somatic stem cells is unknown. Klf5 deficient hematopoietic stem cells and progenitors (HSC/P) fail to engraft after transplantation. This HSC/P defect was associated with impaired bone marrow (BM) homing and lodging and decreased retention in BM. The Klf5/ HSC/P homing defect associated with decreased adhesion to fibronectin and expression of membrane-bound 1/2-integrins. In vivo inducible gain-of-function of Klf5 in HSC translated into increased HSC/P adhesion. The expression of Rab5 family members, mediators of 1/2-integrin recycling in the early endosome, was decreased in Klf5/ HSC/P. Klf5 binds directly to the promoter of Rab5a/b and overexpression of Rab5b rescued the expression of activated 1/2-integrins, adhesion and BM homing of Klf5/ HSC/P. Altogether, these data indicate that Klf5 is indispensable for adhesion, homing, lodging and retention of HSC/P in the BM through Rab5-dependent post-translational regulation of Beta1/Beta2 integrins.
Klf5 controls bone marrow homing of stem cells and progenitors through Rab5-mediated β1/β2-integrin trafficking.
Specimen part
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