Background: Drugs used in cancer treatment specifically kill T regulatory cells. Objective: To determine different phenotypes of T regulatory cells during the maintenance phase chemotherapy for pediatric acute lymphoblastic leukemia (ALL). Materials: We evaluated the percentages of regulatory T cells by flow cytometry. Soluble CTLA-4 (sCTLA-4) ...

CD4+CD25+ regulatory T (Treg) cells are immunosuppressive and help maintain peripheral immune tolerance. The forkhead/winged helix family member, Foxp3, has been shown to be a critical regulator of CD4+CD25+ Treg cells. We demonstrate by quantitative real-time PCR that CD4+CD25+ T cells express higher levels of Foxp3 mRNA than other T cell populations. Recombinant adeno-associated virus vector ...

CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) regulate disease-associated immunity and excessive inflammatory responses, and numbers of CD4(+)CD25(+)Foxp3(+) Tregs are increased during malaria infection. The mechanisms governing their generation, however, remain to be elucidated. In this study we investigated the role of commonly accepted factors for Foxp3 induction, TCR stimulation and cyto...

The suppressive function of regulatory T cells (Tregs) is critical to the maintenance of immune homeostasis in vivo and yet, the specific identification of Tregs by phenotypic markers is not perfect. Tregs were originally identified in the CD4+CD25+ fraction of T cells, but FoxP3 expression was later included as an additional marker of Tregs as FoxP3 expression was identified as being critical ...

Chronic activity of hepatitis B is thought to involve aberrant immune tolerance of unknown mechanism. In this study, we examined the role of CD4(+)CD25(+)Foxp3(+) regulatory T cells in disease activity and viral clearance in hepatitis B. Patients with chronic active hepatitis B (CAH) and asymptomatic HBV carriers (AsC) exhibited a significantly high frequency of CD4(+)CD25(+)Foxp3(+) T cells as...

CD4+CD25+high Foxp3 regulatory T (Treg) cells are known to play a key role in balancing immune response to maintain peripheral tolerance against harmless antigens or allergens. Defective immunological suppression by CD4+CD25+high Foxp3 Treg cells can be a cause of the inflammation that leads to an allergic condition such as asthma. The aims of the study are to (1) determine CD4+CD25+high Foxp3 ...

Foxp3 is a master gene of Treg cells, a novel subset of CD4(+) T cells primarily expressing CD25. We describe here different features in Foxp3 expression profile between normal and leukemic CD4(+)CD25(+) T cells, using peripheral blood samples from healthy controls (HCs), human T-cell leukemia virus type-1 (HTLV-1)-infected asymptomatic carriers (ACs), patients with adult T-cell leukemia (ATL),...

CD4+CD25+ regulatory T cells (CD4+CD25+ Tregs) have been shown to play a regulatory or suppressive role in the immune response and are possibly relevant to the pathogenesis of autoimmune diseases. In the present study, we attempted to investigate the frequency of CD4+CD25+ Tregs in peripheral blood (PB) of collagen-induced arthritis (CIA) rats during the development of arthritis, to determine w...

Foxp3 expression was initially thought to be restricted to the CD4(+)CD25(+) regulatory T-cell population. However, recent studies suggest that forkhead box P3 (Foxp3) is expressed in CD4(+)CD25(-) T cells in aged mice. In the present study in B-cell non-Hodgkin lymphoma (NHL), we found that a subset of intratumoral but not peripheral blood CD4(+)CD25(-) T cells, comprising about 15% of intratu...

Intestinal inflammation can be induced by the reconstitution of T/B cell-deficient mice with low numbers of CD4(+) T lymphocytes depleted of CD25(+)Foxp3(+) regulatory T cells (Treg). Using RAG-knockout mice as recipients of either splenocytes exclusively depleted of CD25(+) cells or FACS-purified CD4(+)CD25(-)Foxp3(-) T cells, we found that the augmentation of potentially colitogenic naïve T c...