title: Plasticity of regulatory T cells under cytokine pressure.
abstract: CD4+ T helper (Th) cells have been divided into different subsets as defined by their cytokine products and functions after their activation. CD4+ T cell subsets are continuously discovered and until now Th1, Th2, Th9, Th17, and regulatory T (Treg) cells have been almost unanimously recognized but yet not completely characterized. The selective production of cytokines by each of the subsets is probably the master key of the mechanisms of immune regulation. The cytokine milieu is extremely important on deciding the fate of T cells. Generally, more than one cytokine is needed for differentiating to a particular lineage and just recently it was shown that this status quo of commitment could be challenged. It is well known that cytokines bind to Type I/II cytokine receptors signaling via Janus kinases (JAKs) followed by activation of Signal Transducer and Activator of Transcription (STAT). STAT molecules work together with other transcription factors (Foxp3, RORgammat and RORalpha, T-bet, GATA3, Runx 1, NFAT, etc.) also controlled by cytokines, in modulating the Th phenotype and functions. In this review, we analyze the plasticity of Treg population focusing on the most recent discoveries on how microenvironmental cytokines refine/modify Treg phenotype and function, thus changing their fate.
authors.affiliation: Antiviral Therapy Department, Stefan S. Nicolau Institute of Virology, Bucharest, Romania. ccdiaconu@yahoo.com
authors.forename: Carmen C
authors.initials: CC
authors.lastname: Diaconu
authors.forename: Ana I
authors.initials: AI
authors.lastname: Neagu
authors.forename: Răzvan
authors.initials: R
authors.lastname: Lungu
authors.forename: Graţiela
authors.initials: G
authors.lastname: Tardei
authors.forename: Irina
authors.initials: I
authors.lastname: Alexiu
authors.forename: Coralia
authors.initials: C
authors.lastname: Bleotu
authors.forename: Mihaela Chivu
authors.initials: MC
authors.lastname: Economescu
authors.forename: Roxana S
authors.initials: RS
authors.lastname: Bumbăcea
authors.forename: Irina
authors.initials: I
authors.lastname: Pele
authors.forename: Dragoş
authors.initials: D
authors.lastname: Bumbăcea
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D016207:Cytokines / Q000235:genetics / Q000276:immunology*; D044127:Epigenesis, Genetic; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000276:immunology; D006801:Humans; D051379:Mice; D050791:STAT Transcription Factors / Q000276:immunology; D015398:Signal Transduction / Q000276:immunology; D050378:T-Lymphocytes, Regulatory / Q000145:classification / Q000166:cytology / Q000276:immunology*
chemical_list: D016207:Cytokines; D051858:Forkhead Transcription Factors; D050791:STAT Transcription Factors