Induced pluripotent stem cells (iPSCs) derived from somatic cells of patients by viral vector-mediated factor transduction represent a powerful tool for biomedical research and may provide a source for cell replacement therapies. However, the proviruses encoding the reprogramming factors represent a major limitation of the current technology because even low vector expression may alter the differentiation potential of the iPSCs and induce malignant transformation. Here we show that fibroblasts from five patients with idiopathic Parkinsons disease (PD) can be efficiently reprogrammed into hiPSCs and subsequently differentiated into dopaminergic neurons. Moreover, we derived PD specific hiPSCs free of reprogramming factors using Cre-recombinase excisable viruses. Upon factor deletion these cells maintain a pluripotent state and intact karyotype. Importantly, these factor-free hiPSCs show a global gene expression profile, which is more closely related to hESCs than to hiPSCs carrying the transgenes. Our results indicate that residual transgene expression in conventional virus-carrying hiPSCs can affect their molecular characteristics and that factor-free hiPSCs therefore represent a more suitable source of cells for modeling of human disease.
Parkinson's disease patient-derived induced pluripotent stem cells free of viral reprogramming factors.
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View SamplesSelection of B cells subjected to hypermutation in germinal centres (GC) during T-dependent (TD) antibody responses yields memory cells and long-lived plasma cells that produce high affinity antibodies biased to foreign antigens rather than self-antigens. GC also form in T-independent (TI) responses to polysaccharide antigens but failed selection results in GC involution and memory cells are not generated. To date there are no markers that allow phenotypic distinction of T-dependent and T-independent germinal centre B cells. We have now compared the global gene expression of GC B cells purified from mice immunized with either TD or TI antigens and identified eighty genes that are differentially expressed in TD GC.
Axon growth and guidance genes identify T-dependent germinal centre B cells.
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View SamplesPancreatic ductal adenocarcinoma (PDA) carries a dismal prognosis and current treatments are only modestly effective. We present evidence that this variation is caused in part by recurrent, pervasive molecular differences between tumors. mRNA expression profiles measured using microdissected PDA clinical samples reveal three dominant subtypes of disease; epithelial, mesenchymal and acinar-like. The classical and quasi-mesenchymal subtypes are observed in human and mouse PDA cell lines. Importantly, responses to cytotoxics and KRAS depletion in human PDA cell lines differ substantially between subtypes, and in opposing directions. Integrated genomics implicate and functional studies support overexpression of the trancription factor GATA6 as a driver of the epithelial subtype. These results provide a molecular framework for evaluating the prospects of personalized treatment in PDA.
Subtypes of pancreatic ductal adenocarcinoma and their differing responses to therapy.
Specimen part, Cell line
View SamplesManuka honey has been shown to inhibit growth in EMRSA-15 by inhibiting cell division, the mode of actin is currently unclear.
Synergy between oxacillin and manuka honey sensitizes methicillin-resistant Staphylococcus aureus to oxacillin.
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View SamplesUsing RNA-seq, we characterize the global AS regulation of the eight Drosophila SR protein family members Overall design: RNA-seq experiments on two replicate samples from 8 individual SR protein knockdown (exptGroup=S), two replicates of simultaneous SR protein knockdown (XL6:B52 & SC35:B52) (exptGroup=D). Each exptGroup includes duplicate of its own non-specific (NS) controls.
SR proteins control a complex network of RNA-processing events.
Specimen part, Subject
View SamplesObjective: to identify the early molecular processes involved in osseointegration associated with a micro roughened and nanosurface featured implants.
Comparative molecular assessment of early osseointegration in implant-adherent cells.
Sex, Specimen part
View SamplesNeuronal differentiation of PC12 cells in response to NGF is a prototypical model in which signal duration determines a biological response. Sustained ERK activity induced by NGF, as compared to transient activity induced by EGF, is critical to the differentiation of these cells. To characterize the transcriptional program activated preferentially by NGF, we compared global gene expression profiles between cells treated with NGF and EGF for 2-4 hrs, when sustained ERK signaling in response to NGF is most distinct from the transient signal elicited by EGF. This analysis identified 69 genes that were preferentially upregulated in response to NGF.
Global expression analysis identified a preferentially nerve growth factor-induced transcriptional program regulated by sustained mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) and AP-1 protein activation during PC12 cell differentiation.
Specimen part, Cell line, Time
View SamplesThe skin is a protective barrier against external insults and any lesion must be rapidly and efficiently repaired. Dermal fibroblasts are the major source of extracellular connective tissue matrix and play an important role in wound healing. Vitamin C is an important water-soluble free radical scavenger and an essential cofactor for collagen synthesis by dermal fibroblasts and, consequently, may contribute to the maintenance of healthy skin. Using microarray analysis, we investigated the effects of long-term exposure to a stable vitamin C derivative, ascorbic acid 2-phosphate (AA2P), in contact-inhibited populations of primary human dermal fibroblasts. Compared with "scorbutic" cells, cells exposed to AA2P increased the expression of genes associated with DNA replication and repair and with the G(2)/M phase of the cell cycle. Consistent with the gene expression changes, AA2P increased the mitogenic stimulation of quiescent fibroblasts by serum factors and cell motility in the context of wound healing. Furthermore, AA2P-treated fibroblasts showed faster repair of oxidatively damaged DNA bases. We propose that vitamin C may protect the skin by promoting fibroblast proliferation, migration, and replication-associated base excision repair of potentially mutagenic DNA lesions, and we discuss the putative involvement of hypoxia-inducible transcription factor-1 and collagen receptor-related signaling pathways.
Gene expression profiling reveals new protective roles for vitamin C in human skin cells.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Impact of brief exercise on circulating monocyte gene and microRNA expression: implications for atherosclerotic vascular disease.
Sex, Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Impact of brief exercise on peripheral blood NK cell gene and microRNA expression in young adults.
Sex, Specimen part
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