Project description:Oligodendrocytes undergo extensive changes as they differentiate from progenitors into myelinating cells. To better understand the; molecular mechanisms underlying this transformation, we performed a comparative analysis using gene expression profiling of A2B5+; oligodendrocyte progenitors and O4+ oligodendrocytes. Cells were sort-purified ex vivo from postnatal rat brain using flow cytometry. Using Affymetrix microarrays, 1707 transcripts were identified with a more than twofold increase in expression inO4+oligodendrocytes. Many genes required for oligodendrocyte differentiation were upregulated in O4+ oligodendrocytes, including numerous genes encoding; myelin proteins. Transcriptional changes included genes required for cell adhesion, actin cytoskeleton regulation, and fatty acid and; cholesterol biosynthesis. At the O4+ stage, there was an increase in expression of a novel proline-rich transmembrane protein (Prmp). Localized to the plasma membrane, Prmp displays adhesive properties that may be important for linking the extracellular matrix to the; actin cytoskeleton. Together, our results highlight the usefulness of this discovery-driven experimental strategy to identify genes relevant; to oligodendrocyte differentiation and myelination. Experiment Overall Design: Whole brain dissociates were prepared from one litter of 10 male postnatal day 7 rat pups for each of the 5 A2B5 bioligcal replicates and the 4 O4+ bioligical replicates. Total RNA was extracted from single A2B5+ and single O4+ cells sorted directly from postnatal day7 rat whole brain dissociates using flow cytometry.
Project description:This study provides an overview of the transcriptional signature of oligodendrocyte progenitor cells (OPCs) exposed to the CSF collected from multiple sclerosis patients with either a relapsing remitting disease course (RRMS) or a confirmed primary progressive diagnosis (PPMS). Using an Affymetrix microarray we were able to detect a set of common and unique genes for each treatment group. Gene ontology analysis revealed a common group of genes involved in protein transport, actin dynamics and response to stress and DNA damage, while the RRMS-specific genes were grouped according to protein complex biogenesis, nuclear transport and RNA processing. The transcriptional signature of progenitors exposed to PPMS was characterized by an up-regulation of the pro-differentiation adhesion molecule Lgals3. We confirmed increased protein levels of its gene product,product; galectin-3 in proliferating OPCs incubated with CSF from PPMS patients and also found a four-fold increase in mRNA transcript levels of galectin-3 in human post-mortem normal-appearing white matter samples of primary progressive MS patients when compared to non-neurological controls. This study will help to better understand the common and specific transcriptional changes induced in the different subtypes of MS and therefore find more specific molecular targets for each disease subtype. Comparison of transcriptional signature by microarray analysis of OPCs treated with RRMS and PPMS CSF.
Project description:Objective: To investigate how anti-CD20 B cell-depleting monoclonal antibodies (ɑCD20 mAb) alter the composition and gene expression of immune cells in meningeal ectopic lymphoid tissue (mELT) and the CSF in a murine model of Multiple Sclerosis (MS). Methods: We utilized a spontaneous chronic experimental autoimmune encephalomyelitis (EAE) model of mice with mutant T and B cell receptors specific for myelin oligodendrocyte glycoprotein (MOG), which develop meningeal inflammatory infiltrates resembling those described in Multiple Sclerosis (MS). We studied the changes in cell composition and gene expression after anti-CD20 treatment in mELT and CSF.
Project description:This study provides an overview of the transcriptional signature of oligodendrocyte progenitor cells (OPCs) exposed to the CSF collected from multiple sclerosis patients with either a relapsing remitting disease course (RRMS) or a confirmed primary progressive diagnosis (PPMS). Using an Affymetrix microarray we were able to detect a set of common and unique genes for each treatment group. Gene ontology analysis revealed a common group of genes involved in protein transport, actin dynamics and response to stress and DNA damage, while the RRMS-specific genes were grouped according to protein complex biogenesis, nuclear transport and RNA processing. The transcriptional signature of progenitors exposed to PPMS was characterized by an up-regulation of the pro-differentiation adhesion molecule Lgals3. We confirmed increased protein levels of its gene product,product; galectin-3 in proliferating OPCs incubated with CSF from PPMS patients and also found a four-fold increase in mRNA transcript levels of galectin-3 in human post-mortem normal-appearing white matter samples of primary progressive MS patients when compared to non-neurological controls. This study will help to better understand the common and specific transcriptional changes induced in the different subtypes of MS and therefore find more specific molecular targets for each disease subtype.
Project description:Inflammation is a key component of pathological angiogenesis. Here we induce cornea neovascularisation using sutures placed into the cornea, and sutures are removed to induce a regression phase. We used whole transcriptome microarray to monitor gene expression profies of several genes