Search results for "T cell"
showing 10 items of 2228 documents
Dendritic cell-based immunotherapy of malignant melanoma: success and limitations.
2007
Dendritic cells (DC) are professional antigen-presenting cells in the immune system which are able to induce primary T-cell responses. Because of their central role in the initiation of immune responses, DC are an important tool for tumor-antigen-specific immunotherapy of cancer. DC vaccination using tumor-antigen-loaded DC has led to tumor regression in individual advanced-stage cancer patients. However, there is a discrepancy between strong and antigen-specific T cell responses in vaccinated cancer patients detectable ex vivo and only weak clinical responses. In most cases the immune system of advanced stage IV cancer patients allows only a temporary anti-tumor response and increasing evi…
Dacarbazine-mediated upregulation of NKG2D ligands on tumor cells activates NK and CD8 T cells and restrains melanoma growth.
2013
International audience; Dacarbazine (DTIC) is a cytotoxic drug widely used for melanoma treatment. However, the putative contribution of anticancer immune responses in the efficacy of DTIC has not been evaluated. By testing how DTIC affects host immune responses to cancer in a mouse model of melanoma, we unexpectedly found that both natural killer (NK) and CD8(+) T cells were indispensable for DTIC therapeutic effect. Although DTIC did not directly affect immune cells, it triggered the upregulation of NKG2D ligands on tumor cells, leading to NK cell activation and IFNγ secretion in mice and humans. NK cell-derived IFNγ subsequently favored upregulation of major histocompatibility complex cl…
Parvovirus H-1-Induced Tumor Cell Death Enhances Human Immune Response In Vitro via Increased Phagocytosis, Maturation, and Cross-Presentation by Den…
2005
Oncotropic and oncolytic viruses have attracted high attention as antitumor agents because they preferentially kill cancer cells in vitro and reduce the incidence of spontaneous, induced, or implanted animal tumors. Some autonomous parvoviruses (H-1, minute virus of mice) and derived recombinant vectors are currently under preclinical evaluation. Still not fully understood, their antitumor properties involve more than just tumor cell killing. Because wild-type parvovirus-mediated tumor cell lysates (TCLs) may trigger antigen-presenting cells (APCs) to augment the host immune repertoire, we analyzed phagocytosis, maturation, and crosspresentation of H-1-induced TCLs by human dendritic cells …
UV Exposure Boosts Transcutaneous Immunization and Improves Tumor Immunity: Cytotoxic T-Cell Priming through the Skin
2010
Immunologic approaches to combat cancer aim at the induction of tumor-reactive immune responses to achieve long-term protection. In this context, we recently developed a transcutaneous immunization (TCI) method using the Toll-like receptor (TLR) 7 agonist imiquimod and a peptide epitope. Application onto intact skin induces potent cytotoxic T lymphocyte (CTL) responses and protection against transplanted tumors. The purpose of this study was to explore the effects of UV irradiation on imiquimod-based TCI. Here we show that skin exposure to low-dose UV light before TCI with imiquimod strongly boosts specific CTL responses leading to memory formation and enhanced tumor protection. Toward the …
AP-1 Transcription Factor Serves as a Molecular Switch between Chlamydia pneumoniae Replication and Persistence
2015
ABSTRACT Chlamydia pneumoniae is a Gram-negative bacterium that causes acute or chronic respiratory infections. As obligate intracellular pathogens, chlamydiae efficiently manipulate host cell processes to ensure their intracellular development. Here we focused on the interaction of chlamydiae with the host cell transcription factor activator protein 1 (AP-1) and its consequence on chlamydial development. During Chlamydia pneumoniae infection, the expression and activity of AP-1 family proteins c-Jun, c-Fos, and ATF-2 were regulated in a time- and dose-dependent manner. We observed that the c-Jun protein and its phosphorylation level significantly increased during C. pneumoniae development.…
FlowCT for the analysis of large immunophenotypic data sets and biomarker discovery in cancer immunology
2022
Key Points FlowCT is a new computational workspace for unveiling cellular diversity and objectively identifying biomarkers in large immune monitoring studies.FlowCT identified T-cell biomarkers predictive of malignant transformation and survival in SMM and active MM data sets.
A halocin acting on Na+/H+ exchanger of Haloarchaea as a new type of inhibitor in NHE of mammals
2006
10 páginas, 3 figuras.
Is ABA involved in tolerance responses to salinity by affecting cytoplasm ion homeostasis in rice cell lines?
2012
Abstract The ability of plant cells to maintain cytoplasm ion homeostasis under saline stress is among the main mechanisms involved in salt tolerance. To cope with excess Na + , cells extrude it from the cytoplasm, which requires expenditure of metabolic energy, provided by H + gradients generated by membrane-bound H + -pumps. ABA is well-known to be involved in physiological processes elicited or enhanced by stresses causing cell dehydration. In this work we studied the possible implication of this plant hormone in the control of salt-induced cellular mechanisms conducting to Na + extrusion from the cytoplasm. We used rice ( Oryza sativa L.) cell lines selected for their different toleranc…
Flow cytometric kinetic assay of the activity of Na+/H+ antiporter in mammalian cells.
2004
Background The Na+/H+ exchanger (NHE) of mammalian cells is an integral membrane protein that extrudes H+ ion in exchange for extracellular Na+ and plays a crucial role in the regulation of intracellular pH (pHi). Thus, when pHi is lowered, NHE extrudes protons at a rate depending of pHi that can be expressed as pH units/s. Methods To abolish the activity of other cellular pH-restoring systems, cells were incubated in bicarbonate-free Dulbecco's modified Eagle's medium buffered with HEPES. Flow cytometry was used to determine pHi with 2′,7′-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein acetoxymethyl ester or 5-(and-6)-carboxy SNARF-1 acetoxymethyl ester acetate, and the appropriate fluo…
4,5,6,7-Tetrahydro-isoxazolo-[4,5-c]-pyridines as a new class of cytotoxic Hsp90 inhibitors.
2014
Hsp90 is considered an interesting therapeutic target for anticancer drug development. Here we describe a new class of 4,5,6,7-tetrahydro-isoxazolo-[4,5-c]-pyridine compounds. A small library of derivatives has been synthesized and investigated. Some reported compounds show interesting properties combining both notable binding to Hsp90 and potent cell growth inhibitory activity. N-5 substitution with a 2,4 resorcinol carboxamide appears crucial for activity. Moreover, a derivative bearing a hydroxamic acid residue bound to C-3 amide portion was found to inhibit both Hsp90 and HDAC6.