The forkhead family transcriptional factor (Foxp3) is an important lineage marker for regulatory T (Treg) cells. Foxp3 expression is primarily restricted to CD4+CD25+ cell population. Recently, an intriguing phenomenon is highlighted that there is a considerable amount of CD4(+)CD25(-)Foxp3(+) T cells present in the peripheral blood of patients with systemic lupus erythematosus (SLE). Up to now...

PURPOSE Regulatory T cells (Tregs) have been implicated as inhibitors of antitumoral immunity, and evidence suggests that elimination of Tregs may augment natural and pharmacologic immunity. We tested for the presence of putative Tregs within renal cell carcinoma (RCC) tumors. EXPERIMENTAL DESIGN We identified 170 patients who underwent radical or partial nephrectomy for clear cell RCC betwee...

Immunological tolerance is maintained by specialized subsets of T cells including CD4(+)CD25(+)FOXP3(+) regulatory cells (Treg). Previous studies established that Treg thymic differentiation or peripheral conversion depend on CD28 and Lck signaling. Moreover, foxp3 gene transfer in murine CD4(+)CD25(-) T lymphocytes results in the acquisition of suppressive functions. However, molecular pathway...

Copolymer-I (COP-I) has unique immune regulatory properties and is a treatment option for multiple sclerosis (MS). This study revealed that COP-I induced the conversion of peripheral CD4+CD25- to CD4+CD25+ regulatory T cells through the activation of transcription factor Foxp3. COP-I treatment led to a significant increase in Foxp3 expression in CD4+ T cells in MS patients whose Foxp3 expressio...

PURPOSE To evaluate the proportional changes of CD4+CD25+Foxp3+ regulatory T cells (Tregs) in maternal peripheral blood during pregnancy and labor at term and preterm. METHODS Peripheral blood was collected from 20 non-pregnant controls and 139 pregnant women (60 at different gestational ages, 48 at term with or without labor, and 31 in threatened or actual preterm labor). CD4+CD25+Foxp3+ Tre...

Naturally occurring CD4+CD25+ regulatory T cells (T reg) are pivotal in suppressing immune responses and maintaining tolerance. The identification of molecules controlling T reg differentiation and function is important in understanding host immune responses in malignancy and autoimmunity. In this study we show that PGE2 enhances the in vitro inhibitory function of human purified CD4+CD25+ T re...

LT-R192G, a mutant of the thermolabile enterotoxin of E. coli, is a potent adjuvant of immunization. Immune responses are generally analyzed at the end of protocols including at least 2 administrations, but rarely after a prime. To investigate this point, we compared B and T cell responses in mice after one and two intrarectal immunizations with 2/6 rotavirus-like particles (2/6-VLP) and LT-R19...

Mice lacking interleukin-7 (IL-7-/- mice) have no signs of autoimmune disease, contrary to other models of lymphopenia. We investigated whether the absence of disease was due to the fact that IL-7 is dispensable for the ontogeny, function, and homeostasis of regulatory CD4+ T cells. We show here that the establishment of the peripheral pool of Foxp3-expressing regulatory cells is IL-7 independe...

The molecular mechanism of the extrathymic generation of adaptive, or inducible, CD4(+)Foxp3(+) regulatory T cells (iTregs) remains incompletely defined. We show that exposure of splenic CD4(+)CD25(+)Foxp3(-) cells to IL-2, but not other common γ-chain cytokines, resulted in Stat5 phosphorylation and induced Foxp3 expression in ∼10% of the cells. Thus, IL-2/Stat5 signaling may be critical for F...