Search results for "CD8"
showing 10 items of 682 documents
Processing and MHC class I presentation of human cytomegalovirus pp65-derived peptides persist despite gpUS2–11-mediated immune evasion
2007
Immune control of human cytomegalovirus (HCMV) infection can be mediated by CD8+cytolytic T lymphocytes (CTL). Adoptive transfer of antiviral CTL confers protection against HCMV reactivation and disease. The tegument protein pp65 and the immediate-early 1 protein (IE1) are recognized to be major CTL targets, even though during productive infection the viral immunoevasion proteins gpUS2–11 act to suppress major histocompatibility complex (MHC) class I-restricted antigen presentation. Thus it was not clear how infected cells could be labelled with antigenic peptides in the face of immunoevasion. We show here that the immunodominant peptide pp65NLVwas presented by MHC class I in cells infected…
Increased innate and adaptive immune responses in induced sputum of young smokers
2015
Background and objectives: It is known that chronic obstructive pulmonary disease (COPD) development process is imperceptible and can be asymptomatic for 20 or more years. It is of great importance to diagnose early inflammatory changes that can lead to COPD in young asymptomatic cigarette smokers. The aim of our study was to analyze the cell spectrum of induced sputum (IS) of young cigarette smokers, with emphasis on T-regulatory cells. Materials and methods: A total of 20 healthy nonallergic smokers, 20 nonsmokers and 20 COPD patients were enrolled in the study. After lung function measurements were taken, we performed sputum induction and analyzed sputum cells. We evaluated the cell coun…
Identification of an Immunogenic Medulloblastoma-Specific Fusion Involving EPC2 and GULP1
2021
Medulloblastoma is the most common malignant brain tumor in children. Immunotherapy is yet to demonstrate dramatic results in medulloblastoma, one reason being the low rate of mutations creating new antigens in this entity. In tumors with low mutational burden, gene fusions may represent a source of tumor-specific neoantigens. Here, we reviewed the landscape of fusions in medulloblastoma and analyzed their predicted immunogenicity. Furthermore, we described a new in-frame fusion protein identified by RNA-Seq. The fusion involved two genes on chromosome 2 coding for the enhancer of polycomb homolog 2 (EPC2) and GULP PTB domain containing engulfment adaptor 1 (GULP1) respectively. By qRT-PCR …
Interleukin-7 (IL-7) knockout mice. Implications for lymphopoiesis and organ-specific immunity.
1998
Interleukin-7 (IL-7) is produced by both immune and non-immune cells including stromal cell lines, B-cells, monocytes/macrophages, follicular dendritic cells, keratinocytes, and gut epithelial cells. The development of IL-7 knockout mice aided to elucidate the role of this multifaceted cytokine in lymphopoiesis. Additionally, IL-7 gene-deleted mice may represent an excellent model in order to define the functional role of locally secreted IL-7 in organ-specific immunity and in anti-microbial responses as well. For instance, analysis of IL-7 gene-deleted mice revealed reduced numbers of total T-lymphocytes with preservation of the CD4/CD8 ratio and increased ratio of alpha beta + T-cells com…
β-Catenin in dendritic cells exerts opposite functions in cross-priming and maintenance of CD8+ T cells through regulation of IL-10
2015
Recent studies have demonstrated that β-catenin in DCs serves as a key mediator in promoting both CD4(+) and CD8(+) T-cell tolerance, although how β-catenin exerts its functions remains incompletely understood. Here we report that activation of β-catenin in DCs inhibits cross-priming of CD8(+) T cells by up-regulating mTOR-dependent IL-10, suggesting blocking β-catenin/mTOR/IL-10 signaling as a viable approach to augment CD8(+) T-cell immunity. However, vaccination of DC-β-catenin(-/-) (CD11c-specific deletion of β-catenin) mice surprisingly failed to protect them against tumor challenge. Further studies revealed that DC-β-catenin(-/-) mice were deficient in generating CD8(+) T-cell immunit…
Direct Evidence for Viral Antigen Presentation during Latent Cytomegalovirus Infection
2021
Murine models of cytomegalovirus (CMV) infection have revealed an immunological phenomenon known as “memory inflation” (MI). After a peak of a primary CD8+ T-cell response, the pool of epitope-specific cells contracts in parallel to the resolution of productive infection and the establishment of a latent infection, referred to as “latency.” CMV latency is associated with an increase in the number of cells specific for certain viral epitopes over time. The inflationary subset was identified as effector-memory T cells (iTEM) characterized by the cell surface phenotype KLRG1+CD127−CD62L−. As we have shown recently, latent viral genomes are not transcriptionally silent. Rather, viral genes are …
Monocyte and lymphocyte apoptosis resistance in acute and chronic brucellosis and its possible implications in clinical management.
2003
This study evaluated the level of susceptibility of monocytes and lymphocytes to spontaneously induced and CH11-induced apoptosis in 16 patients with Brucella infection. The expression of some immunological and apoptotic markers was evaluated. Before therapy, monocytes showed a high level of resistance to spontaneously induced or CH11-induced apoptosis in all patients. In patients with acute infection, this resistance persisted for 10-20 days after treatment was initiated, then decreased; in chronically infected patients, it persisted after 45 days of treatment. Lymphocytes were also more resistant to CH 11-induced apoptosis. The level of activated CD8++ T lymphocytes was high in patients w…
Performance of the QuantiFERON-cytomegalovirus (CMV) assay for detection and estimation of the magnitude and functionality of the CMV-specific gamma …
2012
ABSTRACTThe performance of the QuantiFERON-cytomegalovirus (CMV) assay was compared to that of a flow cytometry intracellular cytokine staining (ICS) method for the detection of CMV-specific gamma interferon (IFN-γ)-producing CD8+T-cell responses in allogeneic stem cell transplant (allo-SCT) recipients and for estimations of their magnitude and functionality. A total of 90 whole-blood specimens from 23 allo-SCT recipients was analyzed by both methods. Overall, the percentage of specimens that yielded concordant results by both methods was 68.8% (κ = 0.691; 95% confidence interval [CI], 0.548 to 0.835), and the sensitivity of the QuantiFERON-CMV assay for the detection of positive IFN-γ T-ce…
Role of bacteria-specific T cells in the immunopathogenesis of reactive arthritis.
1994
Reactive arthritis is a usually self-limited sterile inflammation of joints that follows certain bacterial gastrointestinal or urogenital infections. The immunopathogenesis involves CD4+ T cells, which mediate an antigen-specific TH1 response to bacterial constituents within the joint. Properties of the arthritogenic bacteria and the physicochemical characteristics of the bacterial antigens may contribute to the development of reactive arthritis.
Improved assessment of T-cell receptor (TCR) VB repertoire in clinical specimens: combination of TCR-CDR3 spectratyping with flow cytometry-based TCR…
2002
ABSTRACTAntigen-specific T-cell responses may be described by combining three categories: (i) the specificity and effector functions of a T-cell population, (ii) the quantity of T-cell responses (i.e., the number of responding T cells within the CD4/CD8 population), and (iii) the “quality” of T cells (defined by the T-cell receptor [TCR] structure). Several methods to measure T-cell responses are now available including evaluation of T-cell precursors using limiting dilution, the enzyme-linked immunospot assay, ex vivo TCR variable (v)-segment analysis determined by flow cytometry, and TCR-CDR3 length analysis (spectratyping), as well as identification of peptide-specific T cells using majo…