Search results for "T-Lymphocytes"
showing 10 items of 1380 documents
Reciprocal regulation of the Il9 locus by counteracting activities of transcription factors IRF1 and IRF4.
2017
The T helper 9 (Th9) cell transcriptional network is formed by an equilibrium of signals induced by cytokines and antigen presentation. Here we show that, within this network, two interferon regulatory factors (IRF), IRF1 and IRF4, display opposing effects on Th9 differentiation. IRF4 dose-dependently promotes, whereas IRF1 inhibits, IL-9 production. Likewise, IRF1 inhibits IL-9 production by human Th9 cells. IRF1 counteracts IRF4-driven Il9 promoter activity, and IRF1 and IRF4 have opposing function on activating histone modifications, thus modulating RNA polymerase II recruitment. IRF1 occupancy correlates with decreased IRF4 abundance, suggesting an IRF1-IRF4-binding competition at the I…
Activation of silent mating type information regulation 2 homolog 1 by human chorionic gonadotropin exerts a therapeutic effect on hepatic injury and…
2017
Incidence and prevalence of inflammatory liver diseases has increased over the last years, but therapeutic options are limited. Pregnancy induces a state of immune tolerance, which can result in spontaneous improvement of clinical symptoms of certain autoimmune diseases including autoimmune hepatitis (AIH). We investigated the immune-suppressive mechanisms of the human pregnancy hormone, chorionic gonadotropin (hCG), in the liver. hCG signaling activates silent mating type information regulation 2 homolog 1 (SIRT1), which deacetylates forkhead box o3 (FOXO3a), leading to repression of proapoptotic gene expression, because the immunosuppressive consequence attributed to the absence of caspas…
Caloric Restriction Mimetics Enhance Anticancer Immunosurveillance
2016
International audience; Caloric restriction mimetics (CRMs) mimic the biochemical effects of nutrient deprivation by reducing lysine acetylation of cellular proteins, thus triggering autophagy. Treatment with the CRM hydroxycitrate, an inhibitor of ATP citrate lyase, induced the depletion of regulatory T cells (which dampen anticancer immunity) from autophagy-competent, but not autophagy-deficient, mutant KRAS-induced lung cancers in mice, thereby improving anticancer immunosurveillance and reducing tumor mass. Short-term fasting or treatment with several chemically unrelated autophagy-inducing CRMs, including hydroxycitrate and spermidine, improved the inhibition of tumor growth by chemoth…
Checkpoint Inhibition in Non-Hodgkin's Lymphoma.
2017
As patients continue to die from malignant lymphoma, novel treatment options continue to be warranted. To successfully grow and spread, tumor cells need to escape the immune system; therefore, the augmentation or restoration of immune effectors against the malignant cell could be of great value, as shown, e.g., for allogeneic transplantation. A deepened understanding of the regulation of activation and inhibition of the T cell-based effector mechanisms has led to the development of drugs that are able to modify specific checkpoints of this system and thereby raise an immune response against tumor cells. With dramatic responses observed in Hodgkin's disease (HD), interest has risen to explor…
HMG-CoA reductase promotes protein prenylation and therefore is indispensible for T-cell survival.
2017
AbstractStatins are a well-established family of drugs that lower cholesterol levels via the competitive inhibition of the enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR). In addition, the pleiotropic anti-inflammatory effects of statins on T cells make them attractive as therapeutic drugs in T-cell-driven autoimmune disorders. Since statins do not exclusively target HMGCR and thus might have varying effects on different cell types, we generated a new mouse strain allowing for the tissue-specific deletion of HMGCR. Deletion of HMGCR expression in T cells led to a severe decrease in their numbers with the remaining cells displaying an activated phenotype, with an increased pro…
Trabectedin Overrides Osteosarcoma Differentiative Block and Reprograms the Tumor Immune Environment Enabling Effective Combination with Immune Check…
2016
Abstract Purpose: Osteosarcoma, the most common primary bone tumor, is characterized by an aggressive behavior with high tendency to develop lung metastases as well as by multiple genetic aberrations that have hindered the development of targeted therapies. New therapeutic approaches are urgently needed; however, novel combinations with immunotherapies and checkpoint inhibitors require suitable preclinical models with intact immune systems to be properly tested. Experimental Design: We have developed immunocompetent osteosarcoma models that grow orthotopically in the bone and spontaneously metastasize to the lungs, mimicking human osteosarcoma. These models have been used to test the effica…
Melanoma Lesions Independently Acquire T-cell Resistance during Metastatic Latency
2016
Abstract Melanoma often recurs after a latency period of several years, presenting a T cell–edited phenotype that reflects a role for CD8+ T cells in maintaining metastatic latency. Here, we report an investigation of a patient with multiple recurrent lesions, where poorly immunogenic melanoma phenotypes were found to evolve in the presence of autologous tumor antigen–specific CD8+ T cells. Melanoma cells from two of three late recurrent metastases, developing within a 6-year latency period, lacked HLA class I expression. CD8+ T cell–resistant, HLA class I–negative tumor cells became clinically apparent 1.5 and 6 years into stage IV disease. Genome profiling by SNP arrays revealed that HLA …
Chimeric Antigen Receptor-Engineered T-Cells - A New Way and Era for Lymphoma Treatment.
2019
Background: Patients with refractory or relapsed diffuse large B-cell lymphoma have a poor prognosis with the current standard of care. Objective: Chimeric Antigen Receptor T-cells (CAR T-cells) are functionally reprogrammed lymphocytes, which are able to recognize and kill tumor cells. The aim of this study is to make progress in this area. Method: A mini-review was achieved using the articles published in Web of Science and PubMed in the last year and the new patents were made in this field. Results: The responses to CAR T-cell products axicabtagene ciloleucel and tisagenlecleucel are promising; the objective response rate can reach up to 83%, and the complete response rate ranges betwee…
Immunomodulatory activity of microRNAs: potential implications for multiple myeloma treatment
2015
Multiple myeloma (MM) is an incurable plasma cell neoplasm accounting for about 10% of all hematologic malignancies. Recently, emerging evidence is disclosing the complexity of bone marrow interactions between MM cells and infiltrating immune cells, which have been reported to promote proliferation, survival and drug resistance of tumor cells. MicroRNAs (miRNAs) are small non-coding RNA molecules with regulatory functions in the cell, whose expression has predictive and prognostic value in different malignancies. MiRNAs are gaining increasing interest due to their capability to polarize the immune-response through different mechanisms, which include the molecular reprogramming of immune cel…
Beauvericin and enniatin B effects on a human lymphoblastoid Jurkat T-cell model
2018
Abstract Several mycotoxins exert their effect on the immunological system; some are classified as immunotoxic. Jurkat T-cells were used to study toxic effects of beauvericin (BEA) and enniatin B (ENN B). Both are not legislated mycotoxins with increasing presence in feed and food. Concentrations studied were from 1 to 15 μM at 24, 48 and 72 h. Cell death by increasing the percentage of apoptotic/necrotic cells was: BEA > ENN B. IC50 values ranged from 3 to 7.5 μM for BEA. ENN B 15 μM decreased viability (21-29%). The percentage of apoptotic/necrotic cells was BEA > ENN B at 24 h but not at 48 h. Caspase-3&7 activation profile varied, although both mycotoxins increased this activation. No d…