2019
Lack of correlation of virulence gene profiles of Staphylococcus aureus bacteremia isolates with mortality
Park K, Greenwood-Quaintance K, Cunningham S, Rajagopalan G, Chia N, Jeraldo P, Mandrekar J, Patel R. Lack of correlation of virulence gene profiles of Staphylococcus aureus bacteremia isolates with mortality. Microbial Pathogenesis 2019, 133: 103543. PMID: 31102653, DOI: 10.1016/j.micpath.2019.103543.Peer-Reviewed Original ResearchMeSH KeywordsAgedAged, 80 and overAnimalsBacteremiaBacterial AdhesionBase SequenceCell ProliferationDrug Resistance, BacterialFemaleHLA-DR3 AntigenHumansImmune EvasionMaleMethicillin-Resistant Staphylococcus aureusMiceMice, TransgenicMiddle AgedMinnesotaPolymerase Chain ReactionStaphylococcal InfectionsStaphylococcus aureusSuperantigensVirulenceVirulence FactorsConceptsMethicillin-susceptible S. aureusS. aureus bacteremiaAureus bacteremiaMedical CenterHLA-DR3 transgenic miceStaphylococcus aureus bacteremiaMinnesota Medical CenterLarge medical centerImmune evasion genesVirulence genesVirulence gene profilesNumber of deathsClinical dataClinical valueTransgenic miceClinical practiceIndividual PCR assaysWhole-genome sequencing analysisMortalitySAg genesSurvivorsLack of correlationBacteremiaWGS analysisFunctional assays
2017
Concomitant Disruption of CD4 and CD8 Genes Facilitates the Development of Double Negative αβ TCR+ Peripheral T Cells That Respond Robustly to Staphylococcal Superantigen
Chowdhary VR, Krogman A, Tilahun AY, Alexander MP, David CS, Rajagopalan G. Concomitant Disruption of CD4 and CD8 Genes Facilitates the Development of Double Negative αβ TCR+ Peripheral T Cells That Respond Robustly to Staphylococcal Superantigen. The Journal Of Immunology 2017, 198: 4413-4424. PMID: 28468970, PMCID: PMC5471834, DOI: 10.4049/jimmunol.1601991.Peer-Reviewed Original ResearchConceptsDNT cellsDKO miceClass II moleculesΑβ TCRT cellsBacterial superantigensCD8 coreceptorIntact MHC class ILupus-like autoimmune diseaseEnterotoxin BHLA-DQ8 moleculesMHC class II moleculesAnti-nuclear AbsPeripheral T cellsDouble knockout miceMurine MHC class II moleculesMHC class IThymic positive selectionStaphylococcal enterotoxin BCD4/CD8 coreceptorsRegulatory cellsHLA-DR3Splenic CD3WT miceAutoimmune diseasesPassive therapy with humanized anti-staphylococcal enterotoxin B antibodies attenuates systemic inflammatory response and protects from lethal pneumonia caused by staphylococcal enterotoxin B-producing Staphylococcus aureus
Karau M, Tilahun M, Krogman A, Osborne B, Goldsby R, David C, Mandrekar J, Patel R, Rajagopalan G. Passive therapy with humanized anti-staphylococcal enterotoxin B antibodies attenuates systemic inflammatory response and protects from lethal pneumonia caused by staphylococcal enterotoxin B-producing Staphylococcus aureus. Virulence 2017, 8: 1148-1159. PMID: 27925510, PMCID: PMC5711449, DOI: 10.1080/21505594.2016.1267894.Peer-Reviewed Original ResearchConceptsHLA-DR3 transgenic miceSystemic inflammatory responseOnset of infectionLethal pneumoniaTransgenic miceInflammatory responseB antibodiesHLA class II transgenic miceStrong systemic immune responsePolyclonal human IgGII transgenic miceRobust T cell activationSystemic immune responsesPro-inflammatory cytokinesLethal toxic shockAnti-toxin antibodiesToxigenic Staphylococcus aureusHuman IgGS. aureusStaphylococcus aureusT cell activationAnti-SEB antibodiesStaphylococcal enterotoxin BConventional mouse strainsProphylactic administration
2016
Influence of HLA‐DR polymorphism and allergic sensitization on humoral immune responses to intact pneumococcus in a transgenic mouse model
Sheen Y, Rajagopalan G, Snapper C, Kita H, Wi C, Umaretiya P, Juhn Y. Influence of HLA‐DR polymorphism and allergic sensitization on humoral immune responses to intact pneumococcus in a transgenic mouse model. HLA 2016, 88: 25-34. PMID: 27506953, PMCID: PMC6326101, DOI: 10.1111/tan.12851.Peer-Reviewed Original ResearchConceptsHouse dust miteHumoral immune responseAnti-pneumococcal polysaccharideHLA-DR polymorphismImmune responseHDM sensitizationIntact pneumococciHLA-DR3IgG responsesSerum titersTransgenic miceIntranasal house dust miteAnti-phosphorylcholine IgMHLA-DR3 miceLower humoral immune responseHalf of miceTransgenic mouse modelAllergic sensitizationPneumococcal diseaseIgM responseDR3 miceDust mitePneumococcal polysaccharideMouse modelA-IgG
2015
Superantigen-Producing Staphylococcus aureus Elicits Systemic Immune Activation in a Murine Wound Colonization Model
Kim C, Karau M, Greenwood-Quaintance K, Tilahun A, Krogman A, David C, Pritt B, Patel R, Rajagopalan G. Superantigen-Producing Staphylococcus aureus Elicits Systemic Immune Activation in a Murine Wound Colonization Model. Toxins 2015, 7: 5308-5319. PMID: 26670252, PMCID: PMC4690136, DOI: 10.3390/toxins7124886.Peer-Reviewed Original ResearchConceptsSystemic immune activationImmune activationT cellsS. aureusSerum IL-17 levelsSystemic immunologic effectsIL-17 levelsSpleens of miceWound infection modelImmunologic effectsInflammatory changesHLA-DR3Wound infectionCommon causeTransgenic miceUninfected woundsDay 8Immune systemClinical implicationsInfection modelMiceSkin woundsWoundsMicrobial challengeStaphylococcus aureusSuperantigens produced by catheter-associated Staphylococcus aureus elicit systemic inflammatory disease in the absence of bacteremia
Chung J, Greenwood-Quaintance K, Karau MJ, Tilahun A, Khaleghi SR, Chowdhary VR, David CS, Patel R, Rajagopalan G. Superantigens produced by catheter-associated Staphylococcus aureus elicit systemic inflammatory disease in the absence of bacteremia. Journal Of Leukocyte Biology 2015, 98: 271-281. PMID: 25979434, PMCID: PMC4501677, DOI: 10.1189/jlb.4a1214-577rr.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsCatheter-Related InfectionsCatheters, IndwellingCD4-Positive T-LymphocytesEnterotoxinsGene DeletionHistocompatibility AntigensHumansKidneyLiverLungLymphocyte ActivationMiceMice, TransgenicReceptors, Antigen, T-Cell, alpha-betaSpleenStaphylococcal InfectionsStaphylococcus aureusSuperantigensConceptsS. aureusHLA-DR3 transgenic miceLong intravenous catheterSystemic immune activationSerum cytokine levelsSystemic inflammatory diseaseAbsence of bacteremiaMHC class II moleculesInvasive staphylococcal diseaseToxigenic S. aureusClinical S. aureus isolatesS. aureus isolatesClass II moleculesIsogenic S. aureusCytokine levelsHLA-DR3Immune activationInflammatory diseasesIntravenous cathetersStaphylococcal diseaseRole of SAgsDevice-associated infectionsT cellsClinical consequencesForeign body
2014
Superantigens in Staphylococcus aureus isolated from prosthetic joint infection
Kim C, Karau M, Greenwood-Quaintance K, Tilahun A, David C, Mandrekar J, Patel R, Rajagopalan G. Superantigens in Staphylococcus aureus isolated from prosthetic joint infection. Diagnostic Microbiology And Infectious Disease 2014, 81: 201-207. PMID: 25619753, PMCID: PMC4336809, DOI: 10.1016/j.diagmicrobio.2014.11.007.Peer-Reviewed Original ResearchSystemic Inflammatory Response Elicited by Superantigen Destabilizes T Regulatory Cells, Rendering Them Ineffective during Toxic Shock Syndrome
Tilahun AY, Chowdhary VR, David CS, Rajagopalan G. Systemic Inflammatory Response Elicited by Superantigen Destabilizes T Regulatory Cells, Rendering Them Ineffective during Toxic Shock Syndrome. The Journal Of Immunology 2014, 193: 2919-2930. PMID: 25092888, PMCID: PMC4157092, DOI: 10.4049/jimmunol.1400980.Peer-Reviewed Original ResearchMeSH KeywordsAdoptive TransferAnimalsAntibodiesAntigen-Antibody ComplexEnterotoxinsGlucocorticoid-Induced TNFR-Related ProteinGlucocorticoidsHLA-DR alpha-ChainsHLA-DR beta-ChainsHLA-DR3 AntigenInterferon-gammaInterleukin-17Interleukin-2Lymphocyte ActivationMethicillin-Resistant Staphylococcus aureusMiceMice, TransgenicReceptors, Tumor Necrosis FactorShock, SepticStaphylococcal InfectionsSuperantigensT-Lymphocytes, RegulatoryUp-RegulationConceptsToxic shock syndromeEndogenous TregsRegulatory cellsShock syndromeT cellsGlucocorticoid-induced TNFR family-related receptorCommunity-acquired methicillin-resistant strainsEx vivoHLA-DR3 transgenic miceSerum IFN-γ levelsFailure of TregsSystemic inflammatory responseIL-2/T regulatory (Treg) cellsIFN-γ levelsConventional T cellsLife-threatening infectionsMethicillin-resistant strainsT cell activationS. aureus strainsTreg numbersAdoptive transferIL-17Immune activationInflammatory responseThe Impact of Staphylococcus aureus‐Associated Molecular Patterns on Staphylococcal Superantigen‐Induced Toxic Shock Syndrome and Pneumonia
Tilahun A, Karau M, Ballard A, Gunaratna M, Thapa A, David C, Patel R, Rajagopalan G. The Impact of Staphylococcus aureus‐Associated Molecular Patterns on Staphylococcal Superantigen‐Induced Toxic Shock Syndrome and Pneumonia. Mediators Of Inflammation 2014, 2014: 468285. PMID: 25024509, PMCID: PMC4082930, DOI: 10.1155/2014/468285.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsHLA-DQ AntigensHLA-DR3 AntigenLymphocyte ActivationMice, TransgenicPneumoniaShock, SepticStaphylococcus aureusSuperantigensConceptsPathogen-associated molecular patternsHLA-DQ8 transgenic miceHeat-killed Staphylococcus aureusToxic shock syndromeStaphylococcal superantigensHLA-DR3Shock syndromeMolecular patternsTransgenic miceS. aureus-derived peptidoglycanSerious S. aureus infectionsCytokine/chemokine responsesLipoteichoic acidStaphylococcal toxic shock syndromeS. aureusLife-threatening systemic diseaseAnti-inflammatory roleT cell expansionS. aureus infectionT cell proliferationToxigenic S. aureusStaphylococcus aureusAdaptive immune systemChemokine responsesSystemic diseaseSuperantigen profiling of Staphylococcus aureus infective endocarditis isolates
Chung J, Karau M, Greenwood-Quaintance K, Ballard A, Tilahun A, Khaleghi S, David C, Patel R, Rajagopalan G. Superantigen profiling of Staphylococcus aureus infective endocarditis isolates. Diagnostic Microbiology And Infectious Disease 2014, 79: 119-124. PMID: 24745820, PMCID: PMC4031024, DOI: 10.1016/j.diagmicrobio.2014.03.009.Peer-Reviewed Original ResearchConceptsSuperantigen genesSplenocyte proliferationS. aureusStaphylococcus aureus infective endocarditisMethicillin-susceptible S. aureusMethicillin-resistant S. aureusInfective endocarditis casesEnzyme-linked immunosorbent assayStaphylococcal enterotoxin AInfective endocarditisEndocarditis casesSuperantigen productionMouse splenocyte proliferationPCR-positive isolatesTSST-1EndocarditisImmunosorbent assayEnterotoxin AStaphylococcus aureusAureusProliferationIsolatesMortalityGenes
2012
Chronic Exposure to Staphylococcal Superantigen Elicits a Systemic Inflammatory Disease Mimicking Lupus
Chowdhary VR, Tilahun AY, Clark CR, Grande JP, Rajagopalan G. Chronic Exposure to Staphylococcal Superantigen Elicits a Systemic Inflammatory Disease Mimicking Lupus. The Journal Of Immunology 2012, 189: 2054-2062. PMID: 22798666, PMCID: PMC3462343, DOI: 10.4049/jimmunol.1201097.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAutoantibodiesAutoantigensAutoimmune DiseasesCD28 AntigensCD4-Positive T-LymphocytesEnzyme-Linked Immunosorbent AssayFlow CytometryFluorescent Antibody TechniqueHLA-DQ AntigensHumansInfusions, SubcutaneousLupus Erythematosus, SystemicMiceMice, TransgenicStaphylococcus aureusSuperantigensConceptsSystemic lupus erythematosusT cellsChronic exposureStaphylococcal enterotoxin BLupus erythematosusMouse MHC class II moleculesHLA-DQ8 transgenic miceMultisystem autoimmune inflammatory diseaseEnterotoxin BHLA-DQ8 miceAutoimmune inflammatory diseaseMHC class II moleculesTh1-type cytokinesMini-osmotic pumpsMononuclear cell infiltrationAnti-nuclear AbsClass II moleculesAbsence of diseaseChronic nasalIL-12Inflammatory infiltrateAutoimmune diseasesCell infiltrationInflammatory diseasesPathogenic roleLinezolid Is Superior to Vancomycin in Experimental Pneumonia Caused by Superantigen-Producing Staphylococcus aureus in HLA Class II Transgenic Mice
Karau M, Tilahun A, Schmidt S, Clark C, Patel R, Rajagopalan G. Linezolid Is Superior to Vancomycin in Experimental Pneumonia Caused by Superantigen-Producing Staphylococcus aureus in HLA Class II Transgenic Mice. Antimicrobial Agents And Chemotherapy 2012, 56: 5401-5405. PMID: 22850509, PMCID: PMC3457354, DOI: 10.1128/aac.01080-12.Peer-Reviewed Original ResearchConceptsHLA class II transgenic miceTransgenic miceDR3 transgenic miceII transgenic miceHuman leukocyte antigenS. aureusC57BL/6 miceLeukocyte antigenStaphylococcus aureus virulenceExperimental pneumoniaImmune systemSuperantigensPneumoniaAureus virulenceMiceBacterial protein synthesis inhibitorsProtein synthesis inhibitorStaphylococcus aureusLinezolidPotent activatorSynthesis inhibitorVancomycinAureusGreater protectionSuperior responseThe impact of tacrolimus on the immunopathogenesis of staphylococcal enterotoxin-induced systemic inflammatory response syndrome and pneumonia
Tilahun A, Karau M, Clark C, Patel R, Rajagopalan G. The impact of tacrolimus on the immunopathogenesis of staphylococcal enterotoxin-induced systemic inflammatory response syndrome and pneumonia. Microbes And Infection 2012, 14: 528-536. PMID: 22273732, DOI: 10.1016/j.micinf.2012.01.001.Peer-Reviewed Original ResearchConceptsStaphylococcal superantigensT cell activationChemokine levelsCell activationSystemic inflammatory response syndromeDR3 transgenic miceEfficacy of tacrolimusInflammatory response syndromeHuman leukocyte antigenImpact of tacrolimusPotent immunosuppressive agentPost-exposure treatmentT cell proliferationS. aureus strainsSystemic cytokinesGut dysfunctionSerum cytokinesResponse syndromeImmunosuppressive agentsLeukocyte antigenSystemic pathologyTacrolimusLethal pneumoniaPneumoniaTransgenic mice
2011
Chimeric Anti-Staphylococcal Enterotoxin B Antibodies and Lovastatin Act Synergistically to Provide In Vivo Protection against Lethal Doses of SEB
Tilahun M, Kwan A, Natarajan K, Quinn M, Tilahun A, Xie C, Margulies D, Osborne B, Goldsby R, Rajagopalan G. Chimeric Anti-Staphylococcal Enterotoxin B Antibodies and Lovastatin Act Synergistically to Provide In Vivo Protection against Lethal Doses of SEB. PLOS ONE 2011, 6: e27203. PMID: 22102880, PMCID: PMC3216929, DOI: 10.1371/journal.pone.0027203.Peer-Reviewed Original ResearchConceptsToxic shock syndromeLethal toxic shock syndromeHLA-DR3 transgenic miceStaphylococcal enterotoxin BChimeric human-mouse antibodyShock syndromeT cellsVivo protectionTransgenic micePartial protectionComplete protectionLethal dosesT cell populationsClass II MHCSignificant partial protectionAnti-SEB antibodiesHuman T cellsOnly partial protectionInflammatory cytokinesClinical safetyII MHCB antibodiesVivo modelChimeric antibodyEnterotoxin BHLA-DR3 restricted T cell epitope mimicry in induction of autoimmune response to lupus-associated antigen SmD
Deshmukh U, Sim D, Dai C, Kannapell C, Gaskin F, Rajagopalan G, David C, Fu S. HLA-DR3 restricted T cell epitope mimicry in induction of autoimmune response to lupus-associated antigen SmD. Journal Of Autoimmunity 2011, 37: 254-262. PMID: 21868195, PMCID: PMC3372418, DOI: 10.1016/j.jaut.2011.07.002.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsAntibody FormationAutoantibodiesAutoantigensAutoimmunityEpitopes, T-LymphocyteFemaleHLA-DR3 AntigenHumansHybridomasImmunizationLupus Erythematosus, SystemicLymphocyte ActivationMiceMice, TransgenicMolecular MimicryPeptidesProtein BindingSnRNP Core ProteinsStreptococcus agalactiaeT-LymphocytesVibrio choleraeConceptsSystemic lupus erythematosusHLA-DR3 transgenic miceT cell epitopesHLA-DR3T cellsEpitope levelCell epitopesTransgenic miceMolecular mimicryPathogenesis of SLET cell epitope mimicryAutoreactive T cell clonesT hybridomasHLA-DR3 miceMicrobial peptidesAutoreactive T cellsProduction of autoantibodiesT cell responsesT cell clonesLupus erythematosusLupus autoantigensAutoimmune responseAutoimmune disordersImmunized miceEpitope mimicryHuman Leukocyte Antigen Class II Transgenic Mouse Model Unmasks the Significant Extrahepatic Pathology in Toxic Shock Syndrome
Tilahun A, Marietta E, Wu T, Patel R, David C, Rajagopalan G. Human Leukocyte Antigen Class II Transgenic Mouse Model Unmasks the Significant Extrahepatic Pathology in Toxic Shock Syndrome. American Journal Of Pathology 2011, 178: 2760-2773. PMID: 21641398, PMCID: PMC3124354, DOI: 10.1016/j.ajpath.2011.02.033.Peer-Reviewed Original ResearchConceptsToxic shock syndromeShock syndromeTransgenic miceSmall intestineHLA-DR3 transgenic miceHLA class II moleculesMultiple organ inflammationPotent T cell activatorsKey pathogenic eventClass II moleculesT cell activatorsGut dysfunctionKawasaki diseaseLiver failureHeavy infiltrationHigh morbidityD-GalN.Pathologic changesT lymphocytesExtrahepatic pathologyPathogenic eventsAbsorptive functionD-galactosamineSensitization modelMouse strainsHLA‐DR polymorphism modulates response to house dust mites in a transgenic mouse model of airway inflammation
Rajagopalan G, Tilahun A, Iijima K, David C, Kita H, Juhn Y. HLA‐DR polymorphism modulates response to house dust mites in a transgenic mouse model of airway inflammation. HLA 2011, 77: 589-592. PMID: 21447115, DOI: 10.1111/j.1399-0039.2010.01617.x.Peer-Reviewed Original ResearchConceptsHLA-DR3 transgenic miceHouse dust miteDust miteTransgenic miceTh2-predominant immune responseHouse dust mite extractInterleukin-13 levelsInflammatory cell countsBronchoalveolar lavage fluidTh2-type inflammationTransgenic mouse modelHLA-DR polymorphismAirway inflammationCytokine levelsBAL fluidEosinophil countHLA-DR3Childhood asthmaHLA-DR2Lavage fluidMite extractHLA-DRB1Immune responseInterleukin-4Mouse modelInterferon Gamma-Dependent Intestinal Pathology Contributes to the Lethality in Bacterial Superantigen-Induced Toxic Shock Syndrome
Tilahun A, Holz M, Wu T, David C, Rajagopalan G. Interferon Gamma-Dependent Intestinal Pathology Contributes to the Lethality in Bacterial Superantigen-Induced Toxic Shock Syndrome. PLOS ONE 2011, 6: e16764. PMID: 21304813, PMCID: PMC3033413, DOI: 10.1371/journal.pone.0016764.Peer-Reviewed Original ResearchConceptsToxic shock syndromeTransgenic miceShock syndromePathogenesis of TSSSmall intestineLethal toxic shock syndromeHLA-DR3 transgenic miceSystematic histopathological examinationSystemic cytokine stormMultiple organ dysfunctionRobust T cell activationSevere inflammatory changesSmall bowel pathologyT cell expansionAnti-inflammatory propertiesSignificant pathological changesT cell activationIFN-γ geneGut permeabilityCytokine stormSEB challengeBowel pathologyInflammatory changesOrgan dysfunctionIntestinal pathology
2010
Detrimental Effect of the Proteasome Inhibitor, Bortezomib in Bacterial Superantigen- and Lipopolysaccharide-induced Systemic Inflammation
Tilahun A, Theuer J, Patel R, David C, Rajagopalan G. Detrimental Effect of the Proteasome Inhibitor, Bortezomib in Bacterial Superantigen- and Lipopolysaccharide-induced Systemic Inflammation. Molecular Therapy 2010, 18: 1143-1154. PMID: 20372109, PMCID: PMC2889741, DOI: 10.1038/mt.2010.53.Peer-Reviewed Original ResearchConceptsToxic shock syndromeStaphylococcal enterotoxin BNF-kappaB activationSystemic inflammationSerum levelsBacterial superantigensKappaB activationElevated TNF-alpha levelsTNF-alpha levelsAcute liver failureProteasome inhibitorsSevere systemic inflammationNuclear factor-kappaBSerum biochemical parametersTNF-alpha-induced cell deathSerum TNFLiver failureHistopathological findingsUntreated miceShock syndromeProphylactic useMurine modelImportant cytokineBortezomibFactor-kappaBPotent Neutralization of Staphylococcal Enterotoxin B by Synergistic Action of Chimeric Antibodies
Tilahun M, Rajagopalan G, Shah-Mahoney N, Lawlor R, Tilahun A, Xie C, Natarajan K, Margulies D, Ratner D, Osborne B, Goldsby R. Potent Neutralization of Staphylococcal Enterotoxin B by Synergistic Action of Chimeric Antibodies. Infection And Immunity 2010, 78: 2801-2811. PMID: 20308304, PMCID: PMC2876561, DOI: 10.1128/iai.01121-09.Peer-Reviewed Original ResearchConceptsStaphylococcal enterotoxin BT cell receptorT cell populationsT cell activationHLA-DR3 transgenic miceMouse mAbsHuman peripheral blood mononuclear cellsPeripheral blood mononuclear cellsEnterotoxin BCross-linking T-cell receptorsAntigen-independent proliferationClass II major histocompatibility complex moleculesBlood mononuclear cellsAntigen-presenting cellsChimeric human-mouse antibodyMajor histocompatibility complex moleculesT cell proliferationAntigen-independent activationHistocompatibility complex moleculesAnti-SEB antibodiesCytokine productionMononuclear cellsCytokine secretionMHC-IIPotent neutralization