2022
Dimethyl Fumarate Reduces Inflammation in Chronic Active Multiple Sclerosis Lesions
Zinger N, Ponath G, Sweeney E, Nguyen TD, Lo CH, Diaz I, Dimov A, Teng L, Zexter L, Comunale J, Wang Y, Pitt D, Gauthier SA. Dimethyl Fumarate Reduces Inflammation in Chronic Active Multiple Sclerosis Lesions. Neurology Neuroimmunology & Neuroinflammation 2022, 9: e1138. PMID: 35046083, PMCID: PMC8771666, DOI: 10.1212/nxi.0000000000001138.Peer-Reviewed Original ResearchConceptsChronic active lesionsGlatiramer acetateRim lesionsHuman microgliaDimethyl fumarateMultiple sclerosisActive lesionsChronic active multiple sclerosis lesionsEffects of DMFActive multiple sclerosis lesionsClass III evidenceMarkers of inflammationRelapsing-remitting MSRetrospective observational studyQuantitative susceptibility mappingMultiple sclerosis lesionsActivation stateTreatment-induced changesMRI quantitative susceptibility mappingMicroglial activityGlial activityInflammatory activationMicroglial cellsObservational studyMS lesions
2021
QSM is an imaging biomarker for chronic glial activation in multiple sclerosis lesions
Gillen KM, Mubarak M, Park C, Ponath G, Zhang S, Dimov A, Levine‐Ritterman M, Toro S, Huang W, Amici S, Kaunzner UW, Gauthier SA, Guerau‐de‐Arellano M, Wang Y, Nguyen TD, Pitt D. QSM is an imaging biomarker for chronic glial activation in multiple sclerosis lesions. Annals Of Clinical And Translational Neurology 2021, 8: 877-886. PMID: 33704933, PMCID: PMC8045922, DOI: 10.1002/acn3.51338.Peer-Reviewed Original ResearchConceptsNormal-appearing white matterMyeloid cellsLesion rimReactive oxygen speciesQuantitative susceptibility mappingChronic active lesionsChronic glial activationPro-inflammatory cytokinesBlood-brain barrierWhite matter lesionsAdjacent normal-appearing white matterMultiple sclerosis lesionsGlial activationActivated microgliaHistopathological correlatesChronic inflammationActive lesionsCytokine productionMatter lesionsMS lesionsWhite matterHuman-induced pluripotent stem cellsSclerosis lesionsLesionsLesion perimeter
2018
Enhanced astrocyte responses are driven by a genetic risk allele associated with multiple sclerosis
Ponath G, Lincoln MR, Levine-Ritterman M, Park C, Dahlawi S, Mubarak M, Sumida T, Airas L, Zhang S, Isitan C, Nguyen TD, Raine CS, Hafler DA, Pitt D. Enhanced astrocyte responses are driven by a genetic risk allele associated with multiple sclerosis. Nature Communications 2018, 9: 5337. PMID: 30559390, PMCID: PMC6297228, DOI: 10.1038/s41467-018-07785-8.Peer-Reviewed Original ResearchConceptsMultiple sclerosisAstrocyte responseRisk variantsLocal autoimmune inflammationPeripheral immune cellsCentral nervous system cellsPeripheral immune systemCultured human astrocytesNervous system cellsNF-κB signalingCNS accessDysfunctional lymphocytesAstroglial functionAutoimmune inflammationLymphocytic infiltrateLymphocyte recruitmentImmune cellsGenetic risk allelesGenetic risk variantsMS lesionsMS susceptibilityHuman astrocytesLesion sizeImmune systemSystem cells
2017
Podoplanin is a negative regulator of Th17 inflammation
Nylander AN, Ponath GD, Axisa PP, Mubarak M, Tomayko M, Kuchroo VK, Pitt D, Hafler DA. Podoplanin is a negative regulator of Th17 inflammation. JCI Insight 2017, 2: e92321. PMID: 28878118, PMCID: PMC5621890, DOI: 10.1172/jci.insight.92321.Peer-Reviewed Original ResearchConceptsT cellsIL-17IL-17 secretionDistinct cytokine profilesInflammatory gene signatureTh17-polarizing conditionsTh17 cellsCytokine profileCell subsetsInflammatory responseSkin biopsiesMouse modelPDPN expressionMultiple organsSkin diseasesGene signatureInflammationLymphatic systemCLEC-2PDPNRecent dataDifferent subpopulationsCellsTranscriptional profilesShRNA gene
2016
Myelin phagocytosis by astrocytes after myelin damage promotes lesion pathology
Ponath G, Ramanan S, Mubarak M, Housley W, Lee S, Sahinkaya FR, Vortmeyer A, Raine CS, Pitt D. Myelin phagocytosis by astrocytes after myelin damage promotes lesion pathology. Brain 2016, 140: 399-413. PMID: 28007993, PMCID: PMC5841057, DOI: 10.1093/brain/aww298.Peer-Reviewed Original ResearchMeSH KeywordsAdultAgedAnimalsAnimals, NewbornAstrocytesCell ProliferationCells, CulturedChild, PreschoolCultureCytokinesDemyelinating Autoimmune Diseases, CNSEndocytosisFemaleHumansHydrazonesMacrophagesMaleMiddle AgedMyelin SheathPhagocytosisRatsRats, Sprague-DawleyStrokeTime FactorsTransforming Growth Factor betaConceptsMyelin injuryMyelin phagocytosisMyelin debrisMultiple sclerosis lesionsMultiple sclerosisLesion pathologySclerosis lesionsAcute multiple sclerosis lesionsCentral nervous system pathologyProgressive multifocal leukoencephalopathyNervous system pathologySecretion of chemokinesNF-κB activationElevated chemokine expressionHypertrophic astrocytesMost astrocytesMyelin uptakeMultifocal leukoencephalopathyFirst-line responseAcute lesionsMyelin damageReactive astrocytesChemokine expressionAstroglial responseImmune cells
2003
Glutamate uptake by oligodendrocytes
Pitt D, Nagelmeier IE, Wilson HC, Raine CS. Glutamate uptake by oligodendrocytes. Neurology 2003, 61: 1113-1120. PMID: 14581674, DOI: 10.1212/01.wnl.0000090564.88719.37.Peer-Reviewed Original ResearchMeSH KeywordsAdultAgedAstrocytesAutoradiographyBiological TransportCell SurvivalCells, CulturedDose-Response Relationship, DrugExcitatory Amino Acid Transporter 1Excitatory Amino Acid Transporter 2FemaleGene ExpressionGlutamic AcidHumansIn Situ HybridizationMaleMiddle AgedMultiple SclerosisNeurotoxinsOligodendrogliaRNA, MessengerSpinal CordTritiumTumor Necrosis Factor-alphaConceptsMS white matterEAAT-2EAAT-1White matterExtracellular glutamateGlutamate uptakePredominant cellsHuman oligodendrocytesGlutamate removalProinflammatory cytokine tumor necrosisHuman white matterNormal human white matterCommon pathologic eventGlutamate transporter expressionGlutamate receptor expressionCytokine tumor necrosisExcess extracellular glutamateInhibited glutamate uptakeHigh extracellular glutamateSubsequent overstimulationExcitotoxic damageGlutamate excitotoxicityGlutamate clearanceTumor necrosisReceptor expression