Foxp3+ regulatory T (Treg) cells are crucial for restraining inflammation in a variety of autoimmune diseases, including type 1 diabetes (T1D). However, the transcriptional and functional phenotypes of Treg cells within the pancreatic lesion remain poorly understood. Here we characterized pancreas-infiltrating Treg cells in the NOD mouse model of T1D and uncovered a substantial enrichment of th...

The immune system includes a subpopulation of CD8(+) T cells equipped to inhibit the expansion of follicular T helper (T(FH)) cells, resulting in suppression of autoantibody production and associated lupus-like disease. These CD8(+) T regulatory (Treg) cells recognize Qa-1/peptide complexes on target T(FH) cells and depend on the IL-15 cytokine for development and function. Here we show that th...

Regulatory T cells (Treg) are key players in the maintenance of peripheral tolerance. As a result of suppressive effects on CD4 and CD8 effector T cells, Treg control the adaptive immune system and prevent autoimmunity. In addition, they inhibit B lymphocytes, dendritic cells, and monocytes/macrophages. It is interesting that several recent papers show that CD4 CD25 Treg are also able to inhibi...

Ocular pigment epithelium (PE) cells promote the generation of T regulators (PE-induced Treg cells). Moreover, T cells exposed to PE acquire the capacity to suppress the activation of bystander T cells via TGFbeta. Membrane-bound TGFbeta on iris PE cells interacts with TGFbeta receptors on T cells, leading to the conversion of T cells to CD8(+) Treg cells via a cell contact-dependent mechanism....

An important unresolved question with regard to T regulatory (Treg) cell specificity and suppressive activity is whether allogeneic Treg cells inhibit self-reactive T cells. In the present study, this issue was addressed using IL-2Rbeta-deficient mice that develop rapid lethal autoimmunity due to impaired production of Treg cells. We show that adoptive transfer of completely MHC-mismatched Treg...

Neurons have been neglected as cells with a major immune-regulatory function because they do not express major histocompatibility complex class II. Our data show that neurons are highly immune regulatory, having a crucial role in governing T-cell response and central nervous system (CNS) inflammation. Neurons induce the proliferation of activated CD4+ T cells through B7-CD28 and transforming gr...

BACKGROUND Fingolimod (FTY720) is an immunomodulating drug that inhibits sphingosine-1-phosphate binding and blocks T-cell egress from lymph nodes. We analyzed the effect of FTY720 on the autoimmune T- and B-cell response in autoimmune arthritis and studied the mechanisms by which it alters the function of T cells. METHODS Human leukocyte antigen (HLA)-DR1 humanized mice were immunized with t...

In solid tumors, leukemias, and lymphomas, increased frequencies of functional CD4 CD25high regulatory T cells (Treg cells) have been previously demonstrated. In healthy individuals, Treg cells consist not only of memory but also of naive T cells, which can undergo peripheral expansion and are characterized by a relative enrichment for autoreactive T-cell receptors. Here, we demonstrate in pati...

An active role of T regulatory cells (Treg) and tolerogenic dendritic cells (Tol-DC) is believed important for the induction and maintenance of transplantation tolerance. However, interactions between these cells remain unclear. We induced donor-specific tolerance in a fully MHC-mismatched murine model of cardiac transplantation by simultaneously targeting T cell and DC function using anti-CD45...

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 ...