Like natural CD4(+)CD25(+) Treg cells, TGF-beta-induced Treg cells also prevent allograft rejection in MHC-mismatched organ transplantation models. In analyzing this effect with greater detail, we determined that injection of TGF-beta-induced, alloactivated CD4(+)CD25(+) cells induces antigen-specific immune tolerance in vivo. Increased CD4(+)CD25(+) cells in recipients contribute to this immun...

A subpopulation of peripheral human CD4(+)CD25(+) T cells that expresses CD45RO, histocompatibility leukocyte antigen DR, and intracellular cytotoxic T lymphocyte-associated antigen (CTLA) 4 does not expand after stimulation and markedly suppresses the expansion of conventional T cells in a contact-dependent manner. After activation, CD4(+)CD25(+) T cells express CTLA-4 on the surface detectabl...

The factors that influence the functionality of human CD4(+)CD25(+) regulatory T cells are not well understood. We sought to characterize the effects of dendritic cells (DCs) on the in vitro regulatory activity of CD4(+)CD25(+) T cells obtained from peripheral blood of healthy human donors. Flow cytometry showed that a higher proportion of CD4(+)CD25(+(High)) T cells expressed surface glucocort...

Active suppression by T regulatory (Tr) cells plays an important role in the downregulation of T cell responses to foreign and self-antigens. Mouse CD4(+) Tr cells that express CD25 possess remarkable suppressive activity in vitro and in autoimmune disease models in vivo. Thus far, the existence of a similar subset of CD25(+)CD4(+) Tr cells in humans has not been reported. Here we show that hum...

Antigen-specific immunotherapy, an approach to selectively block autoimmune diabetes, generally declines in nonobese diabetic (NOD) mice as disease progresses. To define the parameters influencing the efficacy of antigen-specific immunotherapy once diabetes is established, plasmid DNA (pDNA) vaccination was used to suppress autoimmune-mediated destruction of syngeneic islet grafts in diabetic N...

Biomarkers that can identify tuberculosis (TB) disease and serve as markers for efficient therapy are requested. We have studied T cell cytokine production [interferon (IFN)-γ, interleukin (IL)-2, tumour necrosis factor (TNF)-α] and degranulation (CD107a) as well as subsets of CD4(+) T regulatory cells (Tregs ) after in-vitro Mycobacterium tuberculosis (Mtb) antigen stimulation [early secretory...

CD8+CD25+ cells, which expressed high levels of Foxp3, glucocorticoid-induced tumor necrosis factor receptor (GITR), CCR8, tumor necrosis factor receptor 2 (TNFR2), and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) mRNAs, were identified in the fibrous septa and medullary areas of human thymus. Activated CD8+CD25+ thymocytes did not produce cytokines, but most of them expressed surface C...

The IL-2/IL-2Ralpha (CD25) axis is of central importance for the interplay of effector and regulatory T cells. Nevertheless, the question how different antigen loads are translated into appropriate IL-2 production to ensure adequate responses against pathogens remains largely unexplored. Here we find that at single cell level, IL-2 is binary (digital) and CD25 is graded expressed whereas at pop...

It has been known for years that rodents harbor a unique population of CD4(+)CD25(+) "professional" regulatory/suppressor T cells that is crucial for the prevention of spontaneous autoimmune diseases. Here we demonstrate that CD4(+)CD25(+)CD45RO(+) T cells (mean 6% of CD4(+) T cells) are present in the blood of adult healthy volunteers. In contrast to previous reports, these CD4(+)CD25(+) T cel...

Till min familj 4 5 ABSTRACT Regulatory mechanisms are necessary to avoid the misdirected aggressive immune responses responsible for the pathology seen in autoimmunity and allergy. Thymic-derived CD4 + CD25 + regulatory T cells are indispensible for this regulation. We investigated if CD4 + CD25 + Treg prevents auto-reactive responses in adult peripheral blood and cord blood. Mononuclear cells...