Browsing by Subject "Oligodendrocyte"

Now showing 1 - 4 of 4
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    Differentiation of Human Induced Pluripotent Stem Cells to OLIG2 Positive Ventral Neural Tube Progenitors
    (2020-12) Ravichandran Damodaran, Jeyaram
    Established protocols to generate OPCs from pluripotent stem cells still have several critical drawbacks including being cumbersome, time consuming, and incompatible for autologous stem cell therapies, that have impeded the translation of stem cell derived OPCs in cell transplantation therapies. The 3D culture system employed in these protocols introduces many undefined variables modulating growth factor response by cells. These include variability in culture environment among cells in a batch, differences in cell number and cell density batch to batch, and site to site variations, all of which impact the identity, number and purity of the cells being generated. By constraining to a 2D monolayer system and systematically experimenting with the growth factors and inhibitors currently used to induce OPC differentiation, a shorter, adherent protocol for generating iPSC-derived OLIG2+ ventral neural tube progenitors via an intermediate neuromesodermal progenitor has been developed in the Dutton laboratory.
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    Differentiation of human induced pluripotent stem cells to oligodendrocyte progenitor cells
    (2013-01) Subramaniam, Sandhya
    The similarity between induced Pluripotent Stem Cells (iPSCs) and Embryonic Stem (ES) cells motivated the use of the Keirstead protocol in the differentiation of iPSCs to Oligodendrocyte Progenitor Cells (OPCs). The overall concept of the protocol was successful in differentiating the iPSCs to OPCs with modification at each stage to better suit the survival of the aggregates made from iPSCs. The OPCs generated from the iPSCs were primarily confirmed using immunostaining for Olig2 and NG2. The OPCs produced using this protocol, were expanded on matrigel in Glial Restrictive Medium (GRM) supplemented with Epidermal Growth Factor (EGF) and passaged for further expansion.
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    Direct reprogramming of mouse embryonic fibroblasts to oligodendrocyte progenitor cells using various transcription factors
    (2013-12) Johnston, Alura Lynn
    Spinal cord injury (SCI) is a debilitating disorder that affects numerous aspects of a person's health. After injury, oligodendrocytes (myelinating glial cells) in the damaged spinal cord undergo cell death leading to additional loss of function. Transplantation of oligodendrocyte progenitor cells (OPCs) into injured spinal cords has been shown to increase myelination of axons and improve function in animal models of SCI. Differentiation of human embryonic stem cells (ESCs) and induced pluripotent stem cells (IPSCs) has been proposed to generate OPCs for clinical use. However, using hESCs poses ethical issues and IPSC methods take many weeks to produce OPCs. Various groups have proposed that using direct reprogramming will create a faster method for producing OPCs. Using combinations of transcription factors it was initially found that co-expression of exogenous FoxG1, Sox2, and Brn2 in embryonic fibroblasts can produce a tripotent neural cell lineage that gives rise to neurons and glial cells including oligodendrocytes. It was also shown that FoxG1 and Brn2 alone could produce OPCs. Following these findings it was shown that one transcription factor, Sox2 could produce induced neural stem cells that could differentiate into glial cell types. In this project we attempted to create a population of OPCs using these transcription factors by direct reprogramming of Olig2:CreER mT/mG transgenic mouse embryonic fibroblasts.
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    An improved method for generating oligodendrocyte progenitor cells from murine induced pluripotent stem cells
    (2014-01) Terzic, Dino
    Cell based therapies aiming to restore myelin in the central nervous system offer great hope for treatment of numerous conditions, ranging from multiple sclerosis and the leukodystrophies, to traumatic CNS injury. The oligodendrocyte progenitor cell (OPC) gives rise to functional oligodendrocytes following transplantation into dysmyelinated regions of the central nervous system, and as such represents a candidate for potential therapeutic applications. It can be generated by directed differentiation of a variety of pluripotent stem cells, including embryonic stem cells and induced pluripotent stem cells. The iPS cell is an ideal source for derivation of OPCs, as it offers the advantage of autologous transplants, and a model to study the biology and pathology of OPCs and oligodendrocytes. Existing protocols for deriving OPCs from mouse iPS cells, although a valuable model, are inefficient and not easily reproducible. We improved upon the existing differentiation protocols to increase their consistency and yield of OPCs, by modifying and combining several published methods. We demonstrate robustness of our new method by generating OPCs from several different pluripotent stem cell lines and demonstrating that the OPCs further develop to form functional oligodendrocytes in vivo.