title: Regulatory and effector T-cells are differentially modulated by Dexamethasone.
abstract: It is assumed that the ratio between effector T cells (Teff) and regulatory T cells (Tregs) controls the immune reactivity within the T-cell compartment. The purpose of this study was to investigate if Dexamethasone (Dex) affects Teff and Tregs subsets. Dex induced on Tregs a dose and time-dependent apoptosis which resulted in a relative increase of Teff. After TCR activation, Dex induced a strong proliferative inhibition of Teff, but a weaker proliferative inhibition on Tregs. These effects were modulated by IL-2, which not only restored the proliferative response, but also prevented Dex-induced apoptosis. The highest dose of IL-2 prevented apoptosis on all FOXP3+CD4+ T cells. Meanwhile, the lowest dose only rescued activated Tregs (aTregs), probably related to their CD25 higher expression. Because Dex did not affect the suppressor capacity of aTregs either, our results support the notion that under Dex treatment, the regulatory T-cell compartment maintains its homeostasis.
authors.affiliation: Institute of Immunology, Genetics and Metabolism (INIGEM), Clinical Hospital, University of Buenos Aires, National Council for Scientific and Technological Research, Buenos Aires, Argentina; Department of Microbiology, School of Medicine, University of Buenos Aires, Argentina.
authors.forename: Julieta
authors.initials: J
authors.lastname: Pandolfi
authors.forename: Plácida
authors.initials: P
authors.lastname: Baz
authors.forename: Pablo
authors.initials: P
authors.lastname: Fernández
authors.forename: Ailén
authors.initials: A
authors.lastname: Discianni Lupi
authors.forename: Florencia
authors.initials: F
authors.lastname: Payaslián
authors.forename: Luis Ariel
authors.initials: LA
authors.lastname: Billordo
authors.forename: Leonardo
authors.initials: L
authors.lastname: Fainboim
authors.forename: Lourdes
authors.initials: L
authors.lastname: Arruvito
mesh_terms: D000328:Adult; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects / Q000276:immunology; D003907:Dexamethasone / Q000494:pharmacology*; D005260:Female; D051858:Forkhead Transcription Factors / Q000378:metabolism; D015870:Gene Expression; D006706:Homeostasis; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D009928:Organ Specificity; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000187:drug effects* / Q000276:immunology
chemical_list: D000893:Anti-Inflammatory Agents; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C508017:IL2RA protein, human; D007376:Interleukin-2; D053645:Interleukin-2 Receptor alpha Subunit; D003907:Dexamethasone
keywords: APCs; Apoptosis; Cytokines; Dex; Dexamethasone; Effector T cells; GC; GR; Glucocorticoids; Regulatory T cells; Teff; Tregs; aTregs; activated Tregs; antigen presenting cells; effector T cells; geoMFI; geometric mean fluorescence intensity; glucocorticoid receptor; glucocorticoids; rTregs; regulatory T cells; resting Tregs