Search results for "Cytotoxic T cell"
showing 10 items of 953 documents
Exogenous TNFR2 activation protects from acute GvHD via host T reg cell expansion
2015
Activation of TNFR2 with a novel agonist expands T reg cells in vivo and protects allo-HCT recipients from acute GvHD while sparing antilymphoma and antiinfectious properties of transplanted donor T cells.
Anticancer potential of novel α,β-unsaturated γ-lactam derivatives targeting the PI3K/AKT signaling pathway.
2021
Abstract Six recently synthesized alkyl (Z)-2-(2-oxopyrrolidin-3-ylidene)acetates were evaluated for their potential as cytotoxic and anticancer agents. All compounds were tested in the ERα positive MCF-7, triple negative MDA-MB-231, and Her2+ SKBR-3 breast cancer cell lines. The most lipophilic derivatives, bearing the 4-isopropylphenyl (2) or 4-tert-butylphenyl (3) group at the γ-lactam nitrogen, proved to be cytotoxic against all the cancer cell lines tested (IC50 values ranging from 18 to 63 μM), exerting their greatest activity in SKBR-3 cells, with IC50 values of 33 and 18 μM, respectively. Biological studies showed that the cytotoxic effects of 2 and 3 are accompanied by apoptotic de…
Dermal CD207-Negative Migratory Dendritic Cells Are Fully Competent to Prime Protective, Skin Homing Cytotoxic T-Lymphocyte Responses
2018
Dendritic cells (DCs) are important inducers and regulators of T-cell responses. They are able to activate and modulate the differentiation of CD4+ and CD8+ T cells. In the skin, there are at least five phenotypically distinct DC subpopulations that can be distinguished by differential expression of the cell surface markers CD207, CD103, and CD11b. Previous studies have suggested that dermal CD11b−CD207+ conventional type 1 DCs are indispensable for the priming of a skin homing cytotoxic T-lymphocyte response. However, conventional type 1 DCs are also the only skin DC subset capable of cross-presenting exogenous antigens on major histocompatibility complex class I. Thus, it remained unclear…
Langerhans Cells Suppress CD8+ T Cells In Situ during Mucocutaneous Acute Graft-Versus-Host Disease
2021
Acute graft-versus-host disease (aGVHD) induced by allogenic hematopoietic stem cell transplantation is an immunological disorder in which donor lymphocytes attack recipient organs. It has been proven that recipient nonhematopoietic tissue cells, such as keratinocytes, are sufficient as immunological targets for allogenic donor T cells, whereas Langerhans cells (LCs) are potent professional hematopoietic antigen-presenting cells existing in the target epidermis and eliminated during the early phase of mucocutaneous aGVHD. Moreover, LCs have been reported to negatively regulate various types of immune responses. Here, we present data showing that initial depletion of recipient LCs exacerbate…
Cytotoxic activity of Holothuria tubulosa (Echinodermata) coelomocytes.
2017
Abstract The immune system of marine invertebrates, in particular that of holothurians, still requires further study. Our research showed that coelomocyte cells contained in the coelomic fluid of the sea cucumber, Holothuria tubulosa, are able to lyse, in vitro, red blood cells in rabbits and sheep. A plaque-forming assay showed spherule cells to be the effector cells, able to release cytotoxic molecules after xenogenic cell contact. The coelomocyte lysate supernatant, analysed by polyacrylamide gel electrophoresis overlay technique, using rabbit and sheep erythrocytes, showed two different haemolytic protein patterns: one calcium dependent and the other calcium independent. The fractions o…
Cross-Talk between Myeloid-Derived Suppressor Cells and Mast Cells Mediates Tumor-Specific Immunosuppression in Prostate Cancer.
2018
Abstract Immunotherapy, including the use of checkpoint inhibitors, is a potent therapeutic approach for some cancers, but has limited success with prostate tumors, in which immune suppression is instigated by the tumor. The immunosuppressive capacity of mast cells, which promote adenocarcinoma development in the prostate, prompted our investigation on whether mast cells promote tolerance to SV40 Large-T antigen, the transforming oncogene in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice. The incidence of adenocarcinoma was reduced in the offspring of a cross between TRAMP mice and mast cell–deficient KitWsh mice. TRAMP mice are tolerant to the SV40 Large T antigen, which is o…
NKp46-expressing human gut-resident intraepithelial Vδ1 T cell subpopulation exhibits high antitumor activity against colorectal cancer
2019
γδ T cells account for a large fraction of human intestinal intraepithelial lymphocytes (IELs) endowed with potent anti-tumor activities. However, little is known about their origin, phenotype and clinical relevance in colorectal cancer (CRC). To determine γδ IEL gut-specificity, homing and functions, γδ T cells were purified from human healthy blood, lymph nodes, liver, skin, intestine either disease-free or affected by CRC or generated from thymic precursors. The constitutive expression of NKp46 specifically identifies a new subset of cytotoxic Vδ1 T cells representing the largest fraction of gut-resident IELs. The ontogeny and gut-tropism of NKp46pos/Vδ1 IELs depends both on distinctive …
Analysis of the immune microenvironment in resected non-small cell lung cancer: the prognostic value of different T lymphocyte markers
2016
[EN] The prognosis of non-small cell lung cancer (NSCLC) remains poor and heterogeneous and new biomarkers are needed. As the immune system plays a pivotal role in cancer, the study of immune-related markers may provide valuable prognostic information of NSCLC. In 122 formalin-fixed, paraffin-embedded tumor tissue samples from early-stage NSCLC, tumor and tumor-near stromal areas were microdissected and gene expression levels of conventional and regulatory T cell markers were assessed by quantitative polymerase chain reaction. Also, the presence of infiltrating CD4+, CD8+, and FOXP3+ cells in tumor samples was assessed by immunohistochemistry. The relative proportion of conventional and reg…
Could formaldehyde induce mutagenic and cytotoxic effects in buccal epithelial cells during anatomy classes?
2017
Background Due to increased formaldehyde exposure, carcinogenic to humans, several researches have been studying the potential toxicity and the safe levels for human beings. The aim of this study was to investigate mutagenicity and cytotoxicity in buccal epithelial exfoliated cells (BEC) of students subjected to formaldehyde (FA) during anatomy classes. Material and Methods BEC were collected periodically from 17 volunteers of undergraduate programs, who had participated in practical anatomy classes, before and after FA exposure. Cells were stained according to Feulgen method and then micronucleus test was applied. A total of 1,500 cells were assessed per individual in this study for the mi…
Microenvironment in neuroblastoma: isolation and characterization of tumor-derived mesenchymal stromal cells
2018
Background It has been proposed that mesenchymal stromal cells (MSCs) promote tumor progression by interacting with tumor cells and other stroma cells in the complex network of the tumor microenvironment. We characterized MSCs isolated and expanded from tumor tissues of pediatric patients diagnosed with neuroblastomas (NB-MSCs) to define interactions with the tumor microenvironment. Methods Specimens were obtained from 7 pediatric patients diagnosed with neuroblastoma (NB). Morphology, immunophenotype, differentiation capacity, proliferative growth, expression of stemness and neural differentiation markers were evaluated. Moreover, the ability of cells to modulate the immune response, i.e. …