Search results for "CD8"
showing 10 items of 682 documents
Nanosecond pulsed electric field inhibits malignant melanoma growth by inducing the change of systemic immunity
2019
Background Nanosecond pulsed electric fields (nsPEFs) showed an inhibitory effect on proliferation of malignant melanoma. In this study, the growth of melanoma were inhibited by changing the systemic immunity. Material and Methods C57BL/6 mice with B16 malignant were exposed to 200 pulses of 100 ns duration, 30kV/cm. The mice were executed four days later. T lymphocyte has been extracted from spleen. Cell viability was evaluated by CCK-8 assay. CD3+CD4+ T cells, CD3+CD8+ T cells, regulatory T cells (Treg) and myeloid-derived suppressor cells (MDSC) were analyzed by flow cytometry. TNF-α, IL-2, IL-10, TGF-β, IFN– γ levels in supernatants were assessed by ELISA. Results C57 malignant melanoma…
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…
Cutaneous Exposure to the Superantigen Staphylococcal Enterotoxin B Elicits a T-Cell-Dependent Inflammatory Response
1996
We analyzed the impact of superantigens secreted by skin-colonizing Staphylococci on the skin and the associated lymphoid tissue following epicutaneous application and intracutaneous injection of small amounts of staphylococcal enterotoxin B (SEB). A single intracutaneous injection of 50 ng of SEB elicited a strong inflammatory response in the skin of BALB/c mice. Three to 6 h later, we observed langerhans cell activation, mast cell degranulation, vasodilation, upregulation of ICAM-1, and induction of VCAM-1 on dermal blood vessels, with vascular adhesion of granulocytes. by 12 to 24 h, cell infiltration of the dermis increased, reaching the epidermis. Among the infiltrating leukocytes, a s…
An MHC class II-expressing T cell clone presenting conventional antigen lacks the ability to present bacterial superantigen.
1995
We have analyzed the response of rat T cells to myelin basic protein (MBP) and the bacterial superantigen, staphylococcal enterotoxin E (SEE). Rat T cells reactive with MBP can respond to SEE presented by spleen cells but not to SEE presented by LOA, a rat T cell clone that expresses both I-A and I-E MHC class II molecules, even though LOA is much more efficient than splenic APC in the presentation of MBP. The inability of LOA to present superantigen is not due to a structural difference in MHC II molecules between LOA and the splenic APC or to differential expression of major accessory/adhesion molecules, including CD2, CD5, CD4 and CD44, on LOA. The non-responsiveness of SEE/LOA-induced T…
Regulation of the tolerogenic function of steady-state DCs
2014
Dendritic cells (DCs) are master regulators of T-cell responses. After sensing pathogen-derived molecular patterns (PAMPs), or signals of inflammation and cellular stress, DCs differentiate into potent activators of naive CD4(+) and CD8(+) T cells through a process that is termed DC maturation. By contrast, DCs induce and maintain peripheral T-cell tolerance in the steady state, that is in the absence of overt infection or inflammation. However, the immunological steady state is not devoid of DC-activating stimuli, such as commensal microorganisms, subclinical infections, or basal levels of proinflammatory mediators. In the presence of these activating stimuli, DC maturation must be calibra…
Evidence against a key role for transforming growth factor-beta1 in cytomegalovirus-induced bone marrow aplasia.
1998
During immunodeficiency after sublethal haematoablative treatment, cytomegalovirus (CMV) infection interferes with haematopoietic reconstitution and can cause lethal bone marrow (BM) aplasia. The in vivo model of murine CMV infection has identified the BM stroma as the principal target site of CMV in the haematopoietic cord. The infected cell type is the reticular stromal cell which forms the stromal network and produces essential haemopoietins, such as stem-cell factor (SCF). The expression of SCF was found to be reduced in the infected stroma, but the stromal network was not disrupted and the number of infected stromal cells was too low to explain the functional deficiency. These facts ca…
BNT162b2 induces SARS-CoV-2-neutralising antibodies and T cells in humans
2020
BNT162b2, a lipid nanoparticle (LNP) formulated nucleoside-modified messenger RNA (mRNA) encoding the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein (S) stabilized in the prefusion conformation, has demonstrated 95% efficacy to prevent coronavirus disease 2019 (COVID-19). Recently, we reported preliminary BNT162b2 safety and antibody response data from an ongoing placebo-controlled, observer-blinded phase 1/2 vaccine trial1. We present here antibody and T cell responses from a second, non-randomized open-label phase 1/2 trial in healthy adults, 19-55 years of age, after BNT162b2 prime/boost vaccination at 1 to 30 µg dose levels. BNT162b2 elicited strong antibody …
IL-23 receptor regulates unconventional IL-17-producing T cells that control bacterial infections.
2010
AbstractIL-23 plays an important role in autoimmune tissue inflammation and induces the generation of not fully characterized effector cells that mediate protection against pathogens. In this paper, we established the essential role of IL-23R in the host response against intracellular pathogens. IL-23 was critical for the expansion or maintenance of γδ and double negative (DN) αβ T cells. These cells were rapidly recruited to the site of infection and produced large amounts of IL-17, IFN-γ, and TNF-α. Notably, DN T cells transferred into L. monocytogenes-infected RAG2−/− mice prevented bacterial growth, confirming their protective role against intracellular pathogens. Our results show that …
Induction of tumor peptide-specific cytotoxic T cells under serum-free conditions by mature human dendritic cells
2000
Tumor vaccination strategies using antigen-pulsed dendritic cells (DC) are currently under development. We established an in vitro system using cultured DC from HLA-typed volunteers for the induction of tumor peptide-specific CD8+ T cells. The strength and specificity of the resulting CTL responses were investigated. For stimulation of syngeneic CD8+ T cells two well-defined DC populations were generated: CD1a+ immature DC cultured in the presence of GM-CSF and IL-4 and mature CD83+ DC generated by additional stimulation with a cytokine cocktail. Stimulations were performed under serum-free conditions and in the absence of exogenous cytokines. Analysis of T cell responses showed that mature…
Identification of HLA-A*0201-Restricted T Cell Epitopes Derived from the Novel Overexpressed Tumor Antigen Calcium-Activated Chloride Channel 2
2002
Abstract Vaccination against tumor Ags may become a promising treatment modality especially in cancer types where other therapeutic approaches fail. However, diversity of tumors requires that a multitude of Ags become available. Differential expression in normal vs cancerous tissues, both at the mRNA and the protein level, may identify Ag candidates. We have previously compared transcripts from squamous cell lung cancer and normal lung tissue using differential display analysis, and found a transcript that was overexpressed in malignant cells and was identical with the calcium-activated chloride channel 2 (CLCA2) gene. We have now selected HLA-A2-restricted peptides from CLCA2, and have gen…