Search results for "Gens"
showing 10 items of 3762 documents
Stem Cell-Derived, microRNA-Carrying Extracellular Vesicles: A Novel Approach to Interfering with Mesangial Cell Collagen Production in a Hyperglycae…
2016
Extracellular vesicles (EVs) that are derived from stem cells are proving to be promising therapeutic options. We herein investigate the therapeutic potential of EVs that have been derived from different stem cell sources, bone-marrow (MSC) and human liver (HLSC), on mesangial cells (MCs) exposed to hyperglycaemia. By expressing a dominant negative STAT5 construct (ΔNSTAT5) in HG-cultured MCs, we have demonstrated that miR-21 expression is under the control of STAT5, which translates into Transforming Growth Factor beta (TGFβ) expression and collagen production. A number of approaches have been used to show that both MSC- and HLSC-derived EVs protect MCs from HG-induced damage via the trans…
Human molecular chaperones share with SARS-CoV-2 antigenic epitopes potentially capable of eliciting autoimmunity against endothelial cells: possible…
2020
Severe acute respiratory syndrome corona virus 2 (SARS-CoV-2), the cause of COVID-19 disease, has the potential to elicit autoimmunity because mimicry of human molecular chaperones by viral proteins. We compared viral proteins with human molecular chaperones, many of which are heat shock proteins, to determine if they share amino acid-sequence segments with immunogenic-antigenic potential, which can elicit cross-reactive antibodies and effector immune cells with the capacity to damage-destroy human cells by a mechanism of autoimmunity. We identified the chaperones that can putatively participate in molecular mimicry phenomena after SARS-CoV-2 infection, focusing on those for which endotheli…
Peptide Processing Is Critical for T-Cell Memory Inflation and May Be Optimized to Improve Immune Protection by CMV-Based Vaccine Vectors.
2016
Cytomegalovirus (CMV) elicits long-term T-cell immunity of unparalleled strength, which has allowed the development of highly protective CMV-based vaccine vectors. Counterintuitively, experimental vaccines encoding a single MHC-I restricted epitope offered better immune protection than those expressing entire proteins, including the same epitope. To clarify this conundrum, we generated recombinant murine CMVs (MCMVs) encoding well-characterized MHC-I epitopes at different positions within viral genes and observed strong immune responses and protection against viruses and tumor growth when the epitopes were expressed at the protein C-terminus. We used the M45-encoded conventional epitope HGI…
The Mouse Cytomegalovirus Gene m42 Targets Surface Expression of the Protein Tyrosine Phosphatase CD45 in Infected Macrophages
2016
The receptor-like protein tyrosine phosphatase CD45 is expressed on the surface of cells of hematopoietic origin and has a pivotal role for the function of these cells in the immune response. Here we report that following infection of macrophages with mouse cytomegalovirus (MCMV) the cell surface expression of CD45 is drastically diminished. Screening of a set of MCMV deletion mutants allowed us to identify the viral gene m42 of being responsible for CD45 down-modulation. Moreover, expression of m42 independent of viral infection upon retroviral transduction of the RAW264.7 macrophage cell line led to comparable regulation of CD45 expression. In immunocompetent mice infected with an m42 del…
Different rates of spontaneous mutation of chloroplastic and nuclear viroids as determined by high-fidelity ultra-deep sequencing
2017
[EN] Mutation rates vary by orders of magnitude across biological systems, being higher for simpler genomes. The simplest known genomes correspond to viroids, subviral plant replicons constituted by circular non-coding RNAs of few hundred bases. Previous work has revealed an extremely high mutation rate for chrysanthemum chlorotic mottle viroid, a chloroplastreplicating viroid. However, whether this is a general feature of viroids remains unclear. Here, we have used high-fidelity ultra-deep sequencing to determine the mutation rate in a common host (eggplant) of two viroids, each representative of one family: the chloroplastic eggplant latent viroid (ELVd, Avsunviroidae) and the nuclear pot…
The shared frameshift mutation landscape of microsatellite-unstable cancers suggests immunoediting during tumor evolution
2020
The immune system can recognize and attack cancer cells, especially those with a high load of mutation-induced neoantigens. Such neoantigens are abundant in DNA mismatch repair (MMR)-deficient, microsatellite-unstable (MSI) cancers. MMR deficiency leads to insertion/deletion (indel) mutations at coding microsatellites (cMS) and to neoantigen-inducing translational frameshifts. Here, we develop a tool to quantify frameshift mutations in MSI colorectal and endometrial cancer. Our results show that frameshift mutation frequency is negatively correlated to the predicted immunogenicity of the resulting peptides, suggesting counterselection of cell clones with highly immunogenic frameshift peptid…
Depleted uranium induces human carcinogenesis involving the immune and chaperoning systems: Realities and working hypotheses
2019
Abstract Cancer is caused by a combination of factors, genetic, epigenetics and environmental. Among the latter, environmental pollutants absorbed by contact, inhalation, or ingestion are major proven or suspected culprits. Depleted uranium (DU) is one of them directly pertinent to the military and civilians working in militarized areas. It is considered a weak carcinogen but its implication in cancer development in exposed individuals is supported by various data. Since not all subjects exposed to DU develop cancer, it is likely that DU-dependent carcinogenesis requires cofactors, such as genetic predisposition and deficiencies of the chaperoning and immune systems. It is of the essence to…
Involvement of Thyroid Hormones in Brain Development and Cancer
2021
Simple Summary Development and function of the mammalian brain clearly require precise regulation of gene expression at both the transcriptional and post-transcriptional level. Thyroid hormones have been recognized to play a fundamental role in these processes, by acting at multiple levels and in different brain cell types, through direct effects on transcription, mediated by nuclear receptors, and also by triggering transduction pathways at the plasma membrane. At the same time, due to their effects on proliferation, differentiation, and cell metabolism, thyroid hormones may have a critical role in different kinds of cancer, including brain cancer. Abstract The development and maturation o…
The Role of SVZ Stem Cells in Glioblastoma
2019
As most common primary brain cancer, glioblastoma is also the most aggressive and malignant form of cancer in the adult central nervous system. Glioblastomas are genetic and transcriptional heterogeneous tumors, which in spite of intensive research are poorly understood. Over the years conventional therapies failed to affect a cure, resulting in low survival rates of affected patients. To improve the clinical outcome, an important approach is to identify the cells of origin. One potential source for these are neural stem cells (NSCs) located in the subventricular zone, which is one of two niches in the adult nervous system where NSCs with the capacity of self-renewal and proliferation resid…
Assessment of intratumor immune-microenvironment in colorectal cancers with extranodal extension of nodal metastases
2018
Background: No data is available on the molecular background of the extra-nodal extension (ENE) of lymph node metastasis (LN) in colorectal cancer (CRC). Methods: A series of 22 ENE-positive CRCs was considered and three samples per case were selected (the primary CRC, an ENE-negative and an ENE-positive metastatic LN). Samples (n=66) were analysed by immunohistochemistry for PD-L1, CD4, CD8, CD68 and CD80. Fifteen out of twenty-two cases were further profiled through a hotspot multigene mutational custom panel, including 164 hotspot regions of AKT1, APC, BRAF, CTNNB1, KIT, KRAS, NRAS, PDGFRA, PIK3CA, PTEN and TP53 genes. Results: A significantly higher percentage of CD4-, CD8- and CD68-pos…