Characterization of Dendritic Cells that Induce Tolerance and T Regulatory 1 Cell Differentiation In Vivo

Abstract

Active suppression is mediated by a subpopulation of CD4(+) T cells that prevents autoimmunity. However, the mechanisms involved in their differentiation in vivo are currently under intensive research. Here we show that in vitro culture of bone marrow cells in the presence of IL-10 induces the differentiation of a distinct subset of dendritic cells with a specific expression of CD45RB. These CD11c(low)CD45RB(high) DCs are present in the spleen and lymph nodes of normal mice and are significantly enriched in the spleen of IL-10 Tg mice. These natural or in vitro-derived DCs display plasmacytoid morphology and an immature-like phenotype, and secrete high levels of IL-10 after activation. OVA peptide-pulsed CD11c(low)CD45RB(high) DCs specifically induce tolerance through the differentiation of Tr1 cells in vitro and in vivo. Our findings identify a natural DC subset that induces the differentiation of Tr1 cells and suggest their therapeutic use.

Identification and hormonal regulation of a novel form of NKp30 in human endometrial epithelium

“…NKp30 has also been shown to be important for dendritic cell (DC) maturation [18,19]. Recently, it has been proposed that the appropriate control of the co-stimulation of DC in the peripheral tissues may also induce immune tolerance [20,21]. Endometrial epithelium has been shown to have antigen-presenting ability, a capability that is under hormonal control [22][23][24].…”

Requirement of HMGB1 and RAGE for the maturation of human plasmacytoid dendritic cells

“…Based on their ability to induce IFN-a secretion by PDC, two types of CpG have been described: CpG 2216 (CpG-A), which induces high amounts of IFN-a, and CpG 2006 (CpG-B), which promotes survival, maturation and migration of PDC to the lymph nodes, but induces lower amounts of IFN-a [11][12][13][14]. PDC sustain the priming of naive T cells and their differentiation into Th1/Th2 effectors [15][16][17] or into regulatory T cells [16,[18][19][20][21][22].…”

“…Based on their ability to induce IFN-a secretion by PDC, two types of CpG have been described: CpG 2216 (CpG-A), which induces high amounts of IFN-a, and CpG 2006 (CpG-B), which promotes survival, maturation and migration of PDC to the lymph nodes, but induces lower amounts of . PDC sustain the priming of naive T cells and their differentiation into Th1/Th2 effectors [15][16][17] or into regulatory T cells [16,[18][19][20][21][22].Recent studies shed light on the events involved in the recognition of microbial DNA by human PDC, the only subset of human DC that expresses the Toll-like receptor 9 (TLR9) [12]. Both CpG-A and CpG-B have been shown to activate PDC via TLR9 [23].…”

Pulmonary stromal cells induce the generation of regulatory DC attenuating T‐cell‐mediated lung inflammation

“…Recently, several types of DC with negative regulatory functions, designated as regulatory DC (DCreg), have been reported [3][4][5]. Up to now, regulatory DCreg were generated by culturing imDC in the presence of immunosuppressive cytokines such as IL-10 and TGF-b or immunomodulatory drugs [4][5][6], which does not represent the in vivo physiologic conditions of DCreg in the organ microenvironment. More and more data show that the microenvironment in certain tissues has the ability to induce DC development [7][8][9][10] and also affects the function of DC; for example, DC in brain and kidney display regulatory functions but not T-cell-activating functions [11,12].…”