An ability to monitor cell cycle progression in real time has numerous applications in pluripotent stem cell-based models and therapeutics development. Fluorescence Ubiquitination-based Cell Cycle Indicator (FUCCI) systems enable live monitoring of the cell cycle in stem cells and their differentiated progenies in a non-invasive manner. We describe the generation and characterisation of a cell line with a doxycycline-inducible reporter system, iFUCCI, in the human embryonic stem cell (hESC) line MEL-1.
View Article and Find Full Text PDFPhenylketonuria is a rare autosomal recessive metabolic disorder mainly due to a significant reduction in the enzyme phenylalanine hydroxylase, resulting in elevation of phenylalanine in the blood. Here, we have established two fibroblast-derived induced pluripotent stem cell lines using Sendai virus-based reprogramming. The established induced pluripotent stem cell lines exhibited a normal karyotype and expressed markers of pluripotency assessed through quantitative PCR, flow cytometry and immunocytochemistry.
View Article and Find Full Text PDFWe employed a Sendai virus-based reprogramming method to transform human lymphoblastoid cell lines (LCL) derived from two individuals diagnosed with phenylketonuria (PKU) into induced pluripotent stem cells (iPSC). This reprogramming process involved the expression of the four Yamanaka factors: KLF4, OCT4, SOX2, and C-MYC. The resulting patient-specific iPSCs exhibited a normal karyotype and expressed endogenous pluripotent markers NANOG and OCT-4.
View Article and Find Full Text PDFDespite advances in coronary artery disease treatment and prevention, myocardial damage due to acute myocardial infarction (MI) remains a major cause of morbidity and mortality in the population. Cell-based clinical trials to treat MI have focused on cells derived from the bone marrow or those potentially possessing functional similarities such as skeletal myoblasts or cardiac progenitors isolated from heart biopsies. Any benefits provided by these cells in improving heart function, left ventricular ejection fraction, or extending life expectancy after MI have been credited mostly to paracrine effects.
View Article and Find Full Text PDFThe development of robust suspension cultures of human embryonic stem cells (hESCs) without the use of cell membrane disrupting enzymes or inhibitors is critical for future clinical applications in regenerative medicine. We have achieved this by using long, flexible, and thermoresponsive polymer worms decorated with a recombinant vitronectin subdomain that bridge hESCs, aiding in hESC's natural ability to form embryoid bodies (EBs) and satisfying their inherent requirement for cell-cell and cell-extracellular matrix contact. When the EBs reached an optimal upper size where cytokine and nutrient penetration becomes limiting, these long and flexible polymer worms facilitated EB breakdown via a temperature shift from 37 to 25 °C.
View Article and Find Full Text PDFHuman embryonic stem cell (hESC) derivatives show promise as viable cell therapy options for multiple disorders in different tissues. Recent advances in stem cell biology have lead to the reliable production and detailed molecular characterisation of a range of cell-types. However, the role of mitochondria during differentiation has yet to be fully elucidated.
View Article and Find Full Text PDFUse of stem cells, whether adult or embryonic for clinical applications to treat diseases such as Parkinson's, macular degeneration or Type I diabetes will require a homogenous population of mature, terminally differentiated cells. A current area of intense interest is the development of defined surfaces for stem cell derivation, maintenance, proliferation and subsequent differentiation, which are capable of replicating the complex cellular environment existing in vivo. During development many cellular cues result from integrin signalling induced by the local extracellular matrix.
View Article and Find Full Text PDFHuman embryonic stem cells (hESC) are expected to provide revolutionary therapeutic applications and drug discovery technologies. In order for this to be achieved a reproducible, defined animal component free culture system is required for the scale-up production of undifferentiated hESC. In this work we have investigated the applicability of a recombinantly produced domain of human vitronectin as an extracellular matrix alternative to the common standards Geltrex or Matrigel.
View Article and Find Full Text PDFUnlocking the clinical potential of stem cell based therapies requires firstly elucidation of the biological mechanisms which direct stem cell fate decisions and thereafter, technical advances which allow these processes to be driven in a fully defined culture environment. Strategies for the generation of defined surfaces for human embryonic stem cell (hESC) and mesenchymal stem cell (MSC) culture remain in their infancy. In this paper we outline a simple, effective and efficient method for presenting proteins or peptides on an otherwise non-fouling Layer-by-Layer (LbL) self-assembled surface of hyaluronic acid (HA) and chitosan (CHI).
View Article and Find Full Text PDFUse of flow cytometry to detect pluripotency markers on or in human embryonic stem cells (hESCs) is a powerful analytical tool. However, current staining methodologies for high-content analysis of large numbers of samples utilize large quantities of primary and secondary antibodies, are time consuming, and may suffer from sample-to-sample variability. To circumvent these issues, we have developed a reproducible, quick, and cost-effective method of staining 12 populations of hESCs grown under different conditions by labeling each with a unique optical signature (UOS).
View Article and Find Full Text PDFThe unique pluripotential characteristic of human embryonic stem cells heralds their use in fields such as medicine, biotechnology, biopharmaceuticals, and developmental biology. However, the current availability of sufficient quantities of embryonic stem cells for such applications is limited, and generating sufficient numbers for downstream therapeutic applications is a key concern. In the absence of feeder layers or their conditioned media, human embryonic stem cells readily differentiate to form embryoid bodies, indicating that trophic factors secreted by the feeder layers are required for long-term proliferation and maintenance of pluripotency.
View Article and Find Full Text PDFThe pathways involved in the maintenance of human embryonic stem (hES) cells remain largely unknown, although some signaling pathways have been identified in mouse embryonic stem (mES) cells. Fibroblast feeder layers are used to maintain the undifferentiated growth of hES cells and an examination of the conditioned media (CM) of human neonatal fibroblasts (HNFs) could provide insights into the maintenance of hES cells. The neonatal foreskin fibroblast line (HNF02) used in this study was shown to have a normal 2n = 46, XY chromosomal complement and to support the undifferentiated growth of the Embryonic Stem Cell International Pte.
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