Search results for "Dendritic Cell"
showing 10 items of 447 documents
Cytotoxicity of tumor antigen specific human T cells is unimpaired by arginine depletion.
2013
Tumor-growth is often associated with the expansion of myeloid derived suppressor cells that lead to local or systemic arginine depletion via the enzyme arginase. It is generally assumed that this arginine deficiency induces a global shut-down of T cell activation with ensuing tumor immune escape. While the impact of arginine depletion on polyclonal T cell proliferation and cytokine secretion is well documented, its influence on chemotaxis, cytotoxicity and antigen specific activation of human T cells has not been demonstrated so far. We show here that chemotaxis and early calcium signaling of human T cells are unimpaired in the absence of arginine. We then analyzed CD8(+) T cell activation…
Mouse langerhans cells differentially express an activated T cell-attracting CC chemokine.
1999
Epidermal Langerhans cells represent an immature population of dendritic cells, not yet able to prime naive T cells. Following in vitro culture Langerhans cells mature into potent immunostimulatory cells. We constructed a representative cDNA library of in vitro matured murine Langerhans cells. Applying a differential screening procedure 112 differentially expressed cDNA clones were isolated. Thirty-six clones represented cDNA fragments of the same gene, identifying it to be the most actively expressed gene induced in maturing Langerhans cells. A full-length cDNA was sequenced completely. The open reading frame codes for a protein of 92 amino acids containing a leader peptide of 24 amino aci…
Dermal dendritic cells, but not Langerhans cells, are critical in murine single epicutaneous sensitization
2014
A murine repeated protein-patch model has been established to study epicutaneous sensitization in atopic dermatitis. This model has shown a predominant Th2 and a weak Th1 response in both BALB/c and C57BL/6 mice. However, Th responses induced in the repeated model are not consistent with the generally accepted theory that BALB/c and C57BL/6 mice are Th2 and Th1 prone and are representatives of human atopy and non-atopy, respectively. In this study, a single protein-patch model was established, which showed in addition to the Th2 response, a remarkable Th1 response in C57BL/6 mice, but not in BALB/c mice. Moreover, using muLangerin-DTR mice, we demonstrated that dermal dendritic cells, but n…
Molecular profiling of blastic plasmacytoid dendritic cell neoplasm reveals a unique pattern and suggests selective sensitivity to NF-kB pathway inhi…
2014
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare disease of controversial origin recently recognized as a neoplasm deriving from plasmacytoid dendritic cells (pDCs). Nevertheless, it remains an orphan tumor with obscure biology and dismal prognosis. To better understand the pathobiology of BPDCN and discover new targets for effective therapies, the gene expression profile (GEP) of 25 BPDCN samples was analyzed and compared with that of pDCs, their postulated normal counterpart. Validation was performed by immunohistochemistry (IHC), whereas functional experiments were carried out ex vivo. For the first time at the molecular level, we definitely recognized the cellular derivati…
MAPK3 deficiency drives autoimmunity via DC arming.
2010
DC are professional APC that instruct T cells during the inflammatory course of EAE. We have previously shown that MAPK3 (Erk1) is important for the induction of T-cell anergy. Our goal was to determine the influence of MAPK3 on the capacity of DC to arm T-cell responses in autoimmunity. We report that DC from Mapk3(-/-) mice have a significantly higher membrane expression of CD86 and MHC-II and--when loaded with the myelin oligodendrocyte glycoprotein--show a superior capacity to prime naive T cells towards an inflammatory phenotype than Mapk3(+/+) DC. Nonetheless and as previously described, Mapk3(-/-) mice were only slightly but not significantly more susceptible to myelin oligodendrocyt…
Dendritic cells, engineered to secrete a T-cell receptor mimic peptide, induce antigen-specific immunosuppression in vivo
2003
A T-cell receptor mimic peptide (TCRpep) consisting of an 8-amino-acid peptide, homologous to the transmembrane region of the T-cell receptor (TCR) alpha chain, blocks T-cell activation after systemic application. When dendritic cells (DCs) were transduced to secrete the TCRpep and injected into mice, evidence of immunosuppression was observed. In a CD8-driven allergy model, the injection of DCs transduced with the TCRpep reduced inflammation markedly and in a CD4+ T cell-dependent model of multiple sclerosis (experimental autoimmune encephalitis, EAE), injection of TCRpep-secreting DCs abrogated EAE symptoms and prolonged survival. These effects were antigen specific, because transduced DC…
Dendritic Cells Ameliorate Autoimmunity in the CNS by Controlling the Homeostasis of PD-1 Receptor+ Regulatory T Cells
2012
SummaryMature dendritic cells (DCs) are established as unrivaled antigen-presenting cells (APCs) in the initiation of immune responses, whereas steady-state DCs induce peripheral T cell tolerance. Using various genetic approaches, we depleted CD11c+ DCs in mice and induced autoimmune CNS inflammation. Unexpectedly, mice lacking DCs developed aggravated disease compared to control mice. Furthermore, when we engineered DCs to present a CNS-associated autoantigen in an induced manner, we found robust tolerance that prevented disease, which coincided with an upregulation of the PD-1 receptor on antigen-specific T cells. Additionally, we showed that PD-1 was necessary for DC-mediated induction o…
CD1a and antitumour immune response
2004
Primary immune response is based on the capacity of local professional antigen-presenting cells (whose prototype is represented by dendritic cells, DCs) to take up and present antigens to selected clones of T cells, but also to non-specific effector cells such as macrophages or natural killer cells. The four CD1 proteins, all of which share a limited homology to class I MHC proteins, are differently expressed in various cell types, of both mesenchymal and, as recently described, epithelial lineage. Regarding the role of CD1 molecules in the anti-tumour response, it has been reported that CD1+ dendritic cells are involved in the first steps of the primary immune response in a number of malig…
How do dendritic cells prevent autoimmunity: what is a mature dendritic cell in the mouse?
2001
We appreciate the comment by Morel and Feili-Hariri with regard to our most-recent publication in Trends in Immunology 1xDendritic cells as a tool to induce anergic and regulatory T cells. Jonuleit, H. et al. Trends Immunol. 2001; 7: 394–400Abstract | Full Text | Full Text PDF | Scopus (384)See all References1. We certainly do not argue that other subtypes of dendritic cell (DC) might not be suitable for the induction of tolerance also, but certain experimental differences should be considered, particularly with regard to the maturational status of the murine DCs used by Feili-Hariri et al. 2xImmunotherapy of NOD mice with bone-marrow-derived dendritic cells. Feili-Hariri, M. et al. Diabete…
Differential gene expression analysis identifies murine Cacnb3 as strongly upregulated in distinct dendritic cell populations upon stimulation
2011
Langerhans cells (LCs) represent the dendritic cell (DC) population in the epidermis. Among the set of genes induced in primary mouse LCs in response to stimulation, both isoforms of the voltage-dependent Ca²(+) channel (VDCC) regulatory subunit Cacnb3 as well as the DC maturation marker Fscn1 were upregulated most strongly. Comparable results were obtained for a recently described myeloid DC line (SP37A3). Other antigen presenting cell populations, namely, bone marrow-derived DCs, macrophages and primary B cells, showed no stimulation-associated upregulation of Cacnb3 expression. Pharmacological inhibition of Ca²(+) channel activity during the stimulation of SP37A3 cells enhanced their T c…