2023
Remission of severe myasthenia gravis after autologous stem cell transplantation
Schlatter M, Yandamuri S, O'Connor K, Nowak R, Pham M, Obaid A, Redman C, Provost M, McSweeney P, Pearlman M, Tees M, Bowen J, Nash R, Georges G. Remission of severe myasthenia gravis after autologous stem cell transplantation. Annals Of Clinical And Translational Neurology 2023, 10: 2105-2113. PMID: 37726935, PMCID: PMC10646993, DOI: 10.1002/acn3.51898.Peer-Reviewed Original ResearchConceptsHematopoietic cell transplantationRefractory myasthenia gravisAutologous hematopoietic cell transplantationMyasthenia gravisCell transplantationAcetylcholine receptorsAutologous stem cell transplantationPhase 2 clinical trialAmerica (MGFA) clinical classificationMultiple immunomodulatory agentsRabbit antithymocyte globulinSevere myasthenia gravisAutoimmune neurological disordersHigh-dose chemotherapyMyasthenia Gravis FoundationNeuromuscular junction disordersStem cell transplantationTherapeutic plasma exchangeImmune cell subtypesDays of treatmentEffect of treatmentAntithymocyte globulinDisease activityComplete responseUnderwent treatmentIndividual myasthenia gravis autoantibody clones can efficiently mediate multiple mechanisms of pathology
Pham M, Masi G, Patzina R, Obaid A, Oxendine S, Oh S, Payne A, Nowak R, O’Connor K. Individual myasthenia gravis autoantibody clones can efficiently mediate multiple mechanisms of pathology. Acta Neuropathologica 2023, 146: 319-336. PMID: 37344701, PMCID: PMC11380498, DOI: 10.1007/s00401-023-02603-y.Peer-Reviewed Original ResearchConceptsMyasthenia gravisAntigenic modulationPathogenic mechanismsAutoimmune myasthenia gravisCurrent therapeutic approachesΑ-bungarotoxin bindingNicotinic acetylcholine receptorsReceptor blockadeSerum autoantibodiesAutoreactive clonesMonoclonal levelTherapeutic approachesMonoclonal autoantibodiesAcetylcholine receptorsComplement activationAutoantibodiesAChR subunitsJurkat cell lineDistinct molecular mechanismsPathogenic profilePathogenic capacityPathologyCell-based assaysMAbsPatientsClinicoserological insights into patients with immune checkpoint inhibitor‐induced myasthenia gravis
Masi G, Pham M, Karatz T, Oh S, Payne A, Nowak R, Howard J, Guptill J, Juel V, O'Connor K. Clinicoserological insights into patients with immune checkpoint inhibitor‐induced myasthenia gravis. Annals Of Clinical And Translational Neurology 2023, 10: 825-831. PMID: 36924454, PMCID: PMC10187728, DOI: 10.1002/acn3.51761.Peer-Reviewed Original ResearchMeSH KeywordsAutoantibodiesComplement ActivationHumansImmune Checkpoint InhibitorsMyasthenia GravisReceptors, Cholinergic
2022
Reemergence of pathogenic, autoantibody-producing B cell clones in myasthenia gravis following B cell depletion therapy
Fichtner ML, Hoehn KB, Ford EE, Mane-Damas M, Oh S, Waters P, Payne AS, Smith ML, Watson CT, Losen M, Martinez-Martinez P, Nowak RJ, Kleinstein SH, O’Connor K. Reemergence of pathogenic, autoantibody-producing B cell clones in myasthenia gravis following B cell depletion therapy. Acta Neuropathologica Communications 2022, 10: 154. PMID: 36307868, PMCID: PMC9617453, DOI: 10.1186/s40478-022-01454-0.Peer-Reviewed Original ResearchConceptsB cell depletion therapyB cell clonesMuSK-MG patientsMyasthenia gravisB cellsMG patientsDepletion therapyCell clonesAutoantibody-producing B cellsMuscle-specific tyrosine kinaseComplete stable remissionB cell receptor repertoireCell receptor repertoireValuable candidate biomarkersB cell receptorMG relapseClinical relapseStable remissionDisease relapseAutoimmune disordersRelapsePatientsAcetylcholine receptorsCandidate biomarkersReceptor repertoireNovel pathophysiological insights in autoimmune myasthenia gravis
Masi G, O’Connor K. Novel pathophysiological insights in autoimmune myasthenia gravis. Current Opinion In Neurology 2022, 35: 586-596. PMID: 35942663, PMCID: PMC9458626, DOI: 10.1097/wco.0000000000001088.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsAutoimmune myasthenia gravisMyasthenia gravisMG patientsClinical responseMuscle-specific tyrosine kinaseSpecific therapeutic strategiesNovel pathophysiological insightsMG pathologyMG subtypesAutoantibody repertoireTreatment optionsCancer immunotherapyPredictive biomarkersSuch therapyImmunological heterogeneityPathophysiological insightsMG phenotypeTherapeutic strategiesClinical observationsTherapeutic outcomesAcetylcholine receptorsDisease subtypesTherapeutic perspectivesSubtypesDevelopment of assaysMyasthenia gravis complement activity is independent of autoantibody titer and disease severity
Fichtner ML, Hoarty MD, Vadysirisack DD, Munro-Sheldon B, Nowak RJ, O’Connor K. Myasthenia gravis complement activity is independent of autoantibody titer and disease severity. PLOS ONE 2022, 17: e0264489. PMID: 35290370, PMCID: PMC8923450, DOI: 10.1371/journal.pone.0264489.Peer-Reviewed Original ResearchMeSH KeywordsAutoantibodiesComplement System ProteinsHumansMyasthenia GravisReceptors, CholinergicSeverity of Illness IndexConceptsAutoantibody titersComplement activityDisease activityMyasthenia gravisComplement pathwayAcetylcholine receptor autoantibodiesAutoimmune myasthenia gravisSecondary complement deficiencyClassical complement pathwayAChR autoantibodiesReceptor autoantibodiesClinical statusAutoimmune diseasesHealthy controlsComplement deficiencyPatients associatesStudy subjectsCandidate biomarkersDisease statusDisease severitySignificant associationDisease pathologyTitersAutoantibodiesPatients
2020
Affinity maturation is required for pathogenic monovalent IgG4 autoantibody development in myasthenia gravis
Fichtner ML, Vieni C, Redler RL, Kolich L, Jiang R, Takata K, Stathopoulos P, Suarez PA, Nowak RJ, Burden SJ, Ekiert DC, O’Connor K. Affinity maturation is required for pathogenic monovalent IgG4 autoantibody development in myasthenia gravis. Journal Of Experimental Medicine 2020, 217: e20200513. PMID: 32820331, PMCID: PMC7953735, DOI: 10.1084/jem.20200513.Peer-Reviewed Original ResearchConceptsMyasthenia gravisUnmutated common ancestorPathogenic capacityMuscle-specific tyrosine kinaseAffinity maturationMuSK myasthenia gravisAutoimmune myasthenia gravisMonovalent antigen-binding fragmentsUnique autoantibodiesIgG4 autoantibodiesAutoantibody developmentAutoantibodiesFab-arm exchangeMonoclonal autoantibodiesAntigen-binding fragmentsGravisSomatic mutationsSubnanomolar affinityMAbsMonovalent FabTyrosine kinaseMaturationImmunopathologyAutoimmunityAutoimmune Pathology in Myasthenia Gravis Disease Subtypes Is Governed by Divergent Mechanisms of Immunopathology
Fichtner ML, Jiang R, Bourke A, Nowak RJ, O’Connor K. Autoimmune Pathology in Myasthenia Gravis Disease Subtypes Is Governed by Divergent Mechanisms of Immunopathology. Frontiers In Immunology 2020, 11: 776. PMID: 32547535, PMCID: PMC7274207, DOI: 10.3389/fimmu.2020.00776.Peer-Reviewed Original ResearchConceptsLipoprotein receptor-related protein 4Chronic inflammatory demyelinating polyneuropathyMuSK myasthenia gravisMyasthenia gravisDisease subtypesPathogenic autoantibodiesNeuromyelitis opticaPemphigus vulgarisFab-arm exchangeNeuromuscular junctionAChR myasthenia gravisDistinct immune mechanismsInflammatory demyelinating polyneuropathyAutoimmune myasthenia gravisContribution of complementMuscle-specific kinaseNicotinic acetylcholine receptorsSubtype of diseaseDemyelinating polyneuropathyMG subtypesMG patientsAutoantibody productionClinical benefitAutoimmune diseasesAutoimmune pathology
2019
Characterization of pathogenic monoclonal autoantibodies derived from muscle-specific kinase myasthenia gravis patients
Takata K, Stathopoulos P, Cao M, Mané-Damas M, Fichtner ML, Benotti ES, Jacobson L, Waters P, Irani SR, Martinez-Martinez P, Beeson D, Losen M, Vincent A, Nowak RJ, O’Connor K. Characterization of pathogenic monoclonal autoantibodies derived from muscle-specific kinase myasthenia gravis patients. JCI Insight 2019, 4: e127167. PMID: 31217355, PMCID: PMC6629167, DOI: 10.1172/jci.insight.127167.Peer-Reviewed Original ResearchConceptsMyasthenia gravisMonoclonal autoantibodiesNeuromuscular junctionMuscle-specific tyrosine kinaseMuSK-MG patientsChronic autoimmune disorderMyasthenia gravis patientsSubset of patientsMouse neuromuscular junctionHuman monoclonal autoantibodiesMuSK autoantibodiesAutoimmune mechanismsGravis patientsMG patientsMost patientsPathogenic autoantibodiesAutoimmune disordersMuscle weaknessNeuromuscular transmissionMuSK phosphorylationAutoantibodiesB cellsAcetylcholine receptorsSynaptic differentiationPatients
2017
B cells in the pathophysiology of myasthenia gravis
Yi JS, Guptill JT, Stathopoulos P, Nowak RJ, O’Connor K. B cells in the pathophysiology of myasthenia gravis. Muscle & Nerve 2017, 57: 172-184. PMID: 28940642, PMCID: PMC5767142, DOI: 10.1002/mus.25973.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsMyasthenia gravisB cellsMuscle-specific tyrosine kinaseArchetypal autoimmune diseaseMuscle end platesProduction of autoantibodiesMost patientsPathogenic autoantibodiesAutoimmune diseasesAdaptive immunityHuman studiesAcetylcholine receptorsFunctional AChRsNeuromuscular junctionPostsynaptic proteinsAutoantibodiesCellular immunologyMolecular immunologyGravisImmunopathologyPathologyAChRImmunologyTyrosine kinaseEnd platesAutoantibody-producing plasmablasts after B cell depletion identified in muscle-specific kinase myasthenia gravis
Stathopoulos P, Kumar A, Nowak RJ, O’Connor K. Autoantibody-producing plasmablasts after B cell depletion identified in muscle-specific kinase myasthenia gravis. JCI Insight 2017, 2: e94263. PMID: 28878127, PMCID: PMC5621905, DOI: 10.1172/jci.insight.94263.Peer-Reviewed Original ResearchMeSH KeywordsAdultAgedAged, 80 and overAnimalsAutoantibodiesB-LymphocytesCohort StudiesFemaleHumansImmunologic FactorsLymphocyte DepletionMaleMiceMiddle AgedMyasthenia GravisReceptor Protein-Tyrosine KinasesReceptors, CholinergicRecurrenceRemission InductionRituximabTumor Necrosis Factor Receptor Superfamily, Member 7ConceptsB-cell depletionMuSK-MG patientsMyasthenia gravisCell depletionMG patientsAutoantibody productionDisease relapseB cellsB-cell-mediated autoimmune disordersMuscle-specific kinase myasthenia gravisAntigen-driven affinity maturationCell-mediated autoimmune disordersMuscle-specific tyrosine kinaseAChR myasthenia gravisAutoantibody-producing plasmablastsMuSK myasthenia gravisRituximab-induced remissionSustained clinical improvementB cell compartmentMuSK autoantibodiesClinical improvementPathogenic autoantibodiesSuch relapsesSerum autoantibodiesClinical featuresDurability of the Rituximab Response in Acetylcholine Receptor Autoantibody–Positive Myasthenia Gravis
Robeson KR, Kumar A, Keung B, DiCapua DB, Grodinsky E, Patwa HS, Stathopoulos PA, Goldstein JM, O’Connor K, Nowak RJ. Durability of the Rituximab Response in Acetylcholine Receptor Autoantibody–Positive Myasthenia Gravis. JAMA Neurology 2017, 74: 60-66. PMID: 27893014, DOI: 10.1001/jamaneurol.2016.4190.Peer-Reviewed Original ResearchConceptsDurability of responseMyasthenia gravisRituximab treatmentAnti-AChR antibody levelsB cell-targeted therapiesLong-term clinical responseRetrospective case series studyTreatment of MGEvidence-based practice parametersLast rituximab treatmentRefractory myasthenia gravisSerum cytokine levelsComplete stable remissionSubset of patientsCase series studyMyasthenia Gravis FoundationMG clinicPharmacologic remissionRituximab cyclesSustained remissionAutoantibody levelsInflammatory markersRituximab therapyClinical improvementClinical response