Helios, an Ikaros family transcription factor, is preferentially expressed at the mRNA and protein level in regulatory T cells. Helios expression previously appeared to be restricted to thymic-derived Treg. Consistent with recent data, we show here that Helios expression is inducible in vitro under certain conditions. To understand phenotypic and functional differences between Helios(+) and Hel...

Regulatory T cells (Treg) are commonly identified by CD25 (IL-2R alpha) surface expression and/or intracellular expression of the FOXP3 transcription factor. In addition, Treg are also characterized by low CD127 (IL-7R alpha) expression when compared to conventional T cells and their biology in the periphery is considered essentially independent of IL-7. We further investigated CD127 expression...

Whereas regulatory T (Treg) cells play an important role in the prevention of autoimmunity, increasing evidence suggests that their down-regulatory properties negatively affect immune responses directed against tumors. Treg cells selectively express chemokine receptors CCR4 and CCR8, and specific migration occurs following the release of various chemokines. Neoplastic meningitis (NM) resulting ...

BACKGROUND Dendritic cells (DC) play a key role in initiation and regulation of immune responses. Plasmacytoid DC (pDC), a small subset of DC, characterized as type-I interferon producing cells, are critically involved in anti-viral immune responses, but also mediate tolerance by induction of regulatory T cells (Treg). In this study, we compared the capacity of human pDC and conventional DC (cD...

Regulatory T cell (Treg) from mice bearing a breast tumor were elevated (tumor Treg). In vitro, whereas tumor Treg ability to inhibit tumor-primed CD4(+) T cell activity is comparable to Treg from naive mice (naive Treg), only tumor Treg suppress naive CD8(+) T cell activation and DC function. Neither tumor Treg nor naive Treg can suppress antitumor immunity at the effector phase of the immune ...

Background: Type 1 diabetes (T1D) is a T cell mediated autoimmune disease targeting the insulin-producing β cells within pancreatic islets. Autoimmune diseases may develop as a consequence of altered balance between regulatory (Tregs) and autoreactive T cells. Objectives: To evaluate Treg cells frequency and suppressive function in the peripheral blood of newly diagnosed T1D patients in compari...

Autologous stem cell transplantation (ASCT) is a last resort treatment for refractory juvenile idiopathic arthritis (JIA). It has been shown to induce dramatic and long-term improvements, but the underlying mechanisms remain to be elucidated. We investigated the potential role of regulatory T cells (Treg) in the processes of immune reconstitution and re-establishment of immune tolerance followi...

BACKGROUND CD4(+)CD25(+)FOXP3(+) Regulatory T cells (Treg) play a central role in the immune balance to prevent autoimmune disease. One outstanding question is how Tregs suppress effector immune responses in human. Experiments in mice demonstrated that Treg restrict effector T cell (Teff) responses by deprivation of the growth factor IL-2 through Treg consumption, resulting in apoptosis of Teff...

It is emerging that CD4+Foxp3+ regulatory T (Treg) cells can produce the proinflammatory cytokine IFN-γ when stimulated in a Th1 cytokine environment. In this study, we report that Foxp3+ Treg cells readily produced IFN-γ in vivo in a highly inflammatory model of graft-versus-host disease (GVHD) and during a Th1-dominated immune response to intracellular bacteria. Moreover, stimulation in vitro...

BACKGROUND Regulatory T (Treg) cells play an important role in the maintenance of immune system homeostasis. Multiple myeloma (MM) is a plasma cell disorder frequently associated with impaired immune cell numbers and functions. METHODS We analyzed Treg cells in peripheral blood (n = 207) and bone marrow (n = 202) of pre-malignant and malignant MM patients using flow cytometry. Treg cells and ...