Search results for "CD8"

Inhibition of anti-GD3-ganglioside antibody-induced proliferation of human CD8+ T cells by CD16+ natural killer cells

1994

The ganglioside GD3 has been described as a membrane component of human T cells which is involved in T cell growth. In the present study the activating function of GD3 for human CD4+ and CD8+ T cells was analyzed by five different monoclonal antibodies (mAb) directed against the GD3 molecule. Three mAb U5, Z21 and R24 induced strong proliferation of peripheral blood mononuclear cells and purified CD8+ and CD4+ T cells of normal donors containing less than 5% CD16+ natural killer (NK) cells. In contrast to CD4+ T cells, CD8+ T cells proliferated only weakly in the presence of 15% CD16+ NK cells. The proliferative response of purified CD4+ and CD8+ T cells (< 5% NK cells) correlated with the …

Analysis of memory and effector CD8+ T cell subsets in chronic graft-versus-host disease

2009

In Naive mice in vivo localization of WI specific CD8+CD28- induced cells

2008

Efficient Targeting of Protein Antigen to the Dendritic Cell Receptor DEC-205 in the Steady State Leads to Antigen Presentation on Major Histocompati…

2002

To identify endocytic receptors that allow dendritic cells (DCs) to capture and present antigens on major histocompatibility complex (MHC) class I products in vivo, we evaluated DEC-205, which is abundant on DCs in lymphoid tissues. Ovalbumin (OVA) protein, when chemically coupled to monoclonal alphaDEC-205 antibody, was presented by CD11c+ lymph node DCs, but not by CD11c- cells, to OVA-specific, CD4+ and CD8+ T cells. Receptor-mediated presentation was at least 400 times more efficient than unconjugated OVA and, for MHC class I, the DCs had to express transporter of antigenic peptides (TAP) transporters. When alphaDEC-205:OVA was injected subcutaneously, OVA protein was identified over a …

Expresión de las moléculas del Complejo Mayor de Histocompatibilidad clase II y moléculas co-estimuladoras en carcinomas orales in vitro

2005

El descubrimiento de que el epitelio escamoso estratificado que cubre la mucosa oral podia expresar moleculas del Complejo Mayor de Histocompatibilidad clase II en varias condiciones patologicas de tipo inflamatorio abrio la posibilidad de que los queratinocitos orales sean celulas inmunologicamente activas, las cuales pueden funcionar con .celulas presentadoras de antigenos'ñ. Para una efectiva activacion de los linfocitos T, las celulas presentadoras de antigenos requieren, ademas de la expresion de moleculas del Complejo Mayor de Histocompatibilidad clase II, senales co-estimuladoras. El proposito del presente estudio fue determinar la expresion de moleculas del Complejo Mayor de Histoco…

CD40 signalling induces IL-10-producing, tolerogenic dendritic cells

2010

Dendritic cells (DC) are potent antigen-presenting cells capable to induce efficient antigen-specific T cell responses in vitro and in vivo. Herein, the maturation process is of great significance, as immature DC (iDC) are known to induce rather regulatory than effector T cell differentiation. This study was designed to characterize the role of the CD40-CD40L pathway for differentiation and function of human DC. Therefore, iDC were stimulated through CD40-CD40L interaction by transduction of DC with adenoviral vectors encoding for CD40L (Ad-CD40L). Resulting DC (CD40L-DC) were analysed concerning their phenotype, cytokine profile and T cell stimulatory capacity. Transduction induced a DC ph…

B7-1 and B7-2 act differentially in the induction of a T cell response: their impact for a HLA-matched and HLA-mismatched anti-tumor immunotherapy.

2005

The efficacy of T cell-based immunotherapy is primarily due to efficient cellular activation that requires the engagement of 2 separate signals, i.e., via the T cell receptor complex and via co-stimulatory molecules the prototype of which is CD28. In cellular activation, the CD28 ligands B7-1 (CD80) and B7-2 (CD86) are thought to play nearly identical roles in T cell activation. We monitored the T cell response upon co-culture with HLA Class I-matched and mismatched renal carcinoma cells, respectively, that express different levels of B7-1 and B7-2, respectively. In a HLA Class I-mismatched co-culture, T cell proliferation, IFN-γ and GM-CSF secretion equally depend on the levels of B7-1 and…

Isolation of Differentially Expressed Genes in Epidermal Langerhans Cells

1997

Epidermal Langerhans cells (LC) represent immature dendritic cells (DC) resident in the skin, which are not yet able to prime naive T cells1. In vitro cultivation of LC in the presence of keratinocytes, supplying survival and differentiation signals, induces maturation events in LC2. These are highlighted by the downregulation of the biosynthesis of MHC class II molecules3, by the upregulation of the surface expression of adhesion and costimulatory molecules like CD80, CD86, CD54 and CD584,5, and by the acquisition of a potent immunostimulatory capacity for T cells6. Mature LC are potent inducers of naive T cells. Thus LC represent an ideal model system to investigate the maturation of DC (…

ICOS and CD28 reversely regulate IL-10 on re-activation of human effector T cells with mature dendritic cells

2002

With newly generated ICOS-ligand (ICOS-L)-specific monoclonal antibodies we determined that human Langerhans cells in situ express similar levels of ICOS-L, CD80, and CD86, compared to immature dendritic cells (DC) derived from monocytes in vitro. Maturation of DC strongly up-regulated CD80 and CD86 but did not significantly change ICOS-L levels. On coculture of "naive"CD4(+) T cells with mature DC in the presence of superantigen, ICOS was highly up-regulated on T cells, but played only a secondary role in the CD28-dominated release of TNF-alpha and IFN-gamma, and did not participate in the induction of IL-2. Cocultures of "effector" CD4(+) T cells with mature DC revealed CD28 as the drivin…

Tumor-Derived Lactic Acid Modulates Dendritic Cell Activation and Differentiation.

2004

Abstract The tumor milieu can influence DC differentiation in vivo and in vitro. We analyzed DC differentiation in a 3-dimensional tumor model and propose a new mechanism of DC modulation by the tumor environment. Monocytes were cultured in the presence of IL-4 and GM-CSF within multicellular tumor spheroids (MCTS) generated from urothelial carcinoma (J82, UMUC3) and melanoma cell lines (MelIm, Mel108). Monocytes invaded the tumor spheroids and differentiated into tumor-associated dendritic cells (TADC) that displayed an altered phenotype compared to DC generated without tumor contact. The expression of CD1a was reduced on TADC whereas CD80, CD86 and CD16 were upregulated. In addition, TADC…