Search results for "CD8"
showing 10 items of 682 documents
Refractory coeliac disease: one step closer to the origin of aberrant lymphocytes.
2012
Aberrant intraepithelial lymphocytes (IELs) are the key feature of refractory coeliac disease type II (RCDII), but the cellular origin of these aberrant IELs remains unclear. In a recent paper Schmitz et al 1 further explored previously characterised aberrant IEL cell lines from four patients with RCDII by using a broad spectrum of cell specific markers, RNA array and immunological techniques, to compare these cell lines to IELs from the fetal intestine, the intestine of children and adults and the thymus. IELs are a heterogeneous population of lymphocytes with innate and adaptive features that inhabit the small and large intestine. IELs are important for the maintenance of tolerance to com…
The CD38-Positive and CD38-Negative Subsets of CD34(high)-Positive Primary Acute Myeloid Leukemia Blasts Differ Considerably in the Expression of Imm…
2008
Abstract Acute myeloid leukemia (AML) is thought to arise from a rare putative ‘leukemic stem cell’ that is capable of self-renewal and formation of leukemic blasts. Serial xenotransplantation studies in immunodeficient mice have shown that this leukemia-initiating cell resides at very low numbers within CD34(high)-positive CD38-negative AML cells. Thus, immunotherapeutic approaches successfully eradicating this cell compartment should result in cure from disease. The objective of our study was to characterize the immune phenotype of the CD38-negative and CD38-positive subsets of primary CD34(high)-positive AML blasts ex vivo. We obtained therapeutic leukapheresis products from 17 AML patie…
Antigen dose-dependent suppression of murine IgE responses is mediated by CD4−CD8− double-negative T cells
2010
Background The IgE response against protein antigens is profoundly influenced by the dose used for sensitization. Objective The aim of the study was to identify immune cells that are involved in antigen dose-dependent regulation of IgE formation. Methods Wild-type mice as well as T helper (Th)1-deficient IL-12p40(-/-) and IFN-gamma(-/-) mice were immunized by repeated intraperitoneal injection of either low doses (K01 mice) or high doses (K100 mice) of keyhole limpet haemocyanin adsorbed to aluminium hydroxide. Splenocytes of immunized mice were restimulated in vitro and antigen-dependent T cell proliferation and cytokine production were measured. The frequency of regulatory T cell subsets …
In Vitro Stimulation and Expansion of Human Tumour-Reactive CD8+ Cytotoxic T Lymphocytes by Anti-CD3/CD28/CD137 Magnetic Beads
2011
Adoptive immunotherapy with tumour-reactive CD8(+) cytotoxic T lymphocytes (CTLs) requires efficient in vitro approaches allowing the expansion of CTLs to large numbers prior infusion. Here, we investigated the antigen-independent activation and the expansion of human T cells in peripheral blood mononuclear cells (PBMCs) and in tumour-reactive CTLs using Dynabeads coated with monoclonal antibodies to CD3 and to the costimulatory molecules CD28 and CD137 (4-1BB). T cells in PBMCs showed an increased expansion rate of 15- to 17-fold during a 2-week culture period using antibody-conjugated beads with interleukin-2 (IL-2) added versus IL-2 alone. No significant difference between CD3/CD28 beads…
IL-27 enhances the lymphocyte mediated innate resistance to primary hookworm infection in the lungs
2020
AbstractInterleukin-27 (IL-27) is a heterodimeric cytokine of the IL-12 family, formed by non-covalent association of the promiscuous EBI3 subunit and selective p28 subunit. IL-27 is produced by mononuclear phagocytes and unfolds pleiotropic immune-modulatory functions through high affinity ligation to IL-27 receptor alpha (IL-27RA). While IL-27 is known to contribute to immunity and to end inflammation following numerous types of infections, its relevance for host defense against multicellular parasites is still poorly defined. Here, we investigated the role of IL-27 during infection with the soil-transmitted hookworm, Nippostrongylus brasiliensis, in its early intrapulmonary life cycle. I…
Nucleoprotein-specific nonneutralizing antibodies speed up LCMV elimination independently of complement and FcγR
2013
CD8(+) T cells have an essential role in controlling lymphocytic choriomeningitis virus (LCMV) infection in mice. Here, we examined the contribution of humoral immunity, including nonneutralizing antibodies (Abs), in this infection induced by low virus inoculation doses. Mice with impaired humoral immunity readily terminated infection with the slowly replicating LCMV strain Armstrong but showed delayed virus elimination after inoculation with the faster replicating LCMV strain WE and failed to clear the rapidly replicating LCMV strain Docile, which is in contrast to the results obtained with wild-type mice. Thus, the requirement for adaptive humoral immunity to control the infection was dep…
A2.34 Specific deletion of β-catenin signalling in dendritic cells results in lower Treg expression without influencing the severity of collagen-indu…
2015
Background and objectives Rheumatoid arthritis (RA) is an autoimmune disease characterised by chronic inflammation and synovial infiltration of immune cells. T-cell priming by activated dendritic cells (DCs) contributes to the pathogenesis of RA. DCs are professional antigen presenting cells that have the dual ability to stimulate immunity and maintain tolerance. However, the signalling pathways mediating the tolerogenic DC function in vivo remain largely unknown. Recently, the b-catenin pathway has been suggested to promote a regulatory DC phenotype in vitro . While activation of β-catenin causes the phenotypic maturation of bone marrow-derived DCs, these cells fail to produce immunogenic …
Impact of DLI after In Vivo T-Cell-Depletion: Prophylactic CD8 Depleted or Preemptive CD3pos DLI?
2016
Abstract Introduction: The combination of reduced-intensity conditioning (RIC) with in vivo T-cell depletion by alemtuzumab prior to hematopoietic stem cell transplantation (HSCT) has demonstrated efficient engraftment and reduced graft-versus-host disease (GVHD). However, this regimen is associated with slow lymphocyte recovery leading to a delayed anti-infectious and anti-malignant immunity. DLI can be used to improve immune reconstitution. Here we investigate on the impact of different DLI: prophylactic CD8-depleted DLI vs preemptive non-depleted DLI. Methods: 256 patients with different hematologic malignancies were planned for treatment with DLI after allogeneic HSCT following reduced …
SARS-CoV-2-reactive interferon-γ-producing CD8+ T cells in patients hospitalized with Coronavirus viral disease-2019
2020
There is limited information on SARS-CoV-2 T-cell immune responses in patients with Covid-19. Both CD4+ and CD8+ T cells may be instrumental in the resolution of and protection from SARS-CoV-2 infection. Here, we tested 25 hospitalized patients with either microbiologically documented Covid-19 (n=19) or highly suspected of having the disease (n=6) for the presence of SARS-CoV-2-reactive- CD69+-expressing interferon-gamma;-producing-(IFN-gamma;) CD8+ T cells by a flow-cytometry for intracelular cytokine staining assay. Two sets of overlapping peptides encompassing the SARS-CoV-2 Spike glycoprotein N-terminal 1-643 amino acid sequence and the entire sequence of SARS-CoV-2 M protein were used …
Improved detection of melanoma antigen-specific T cells expressing low or high levels of CD8 by HLA-A2 tetramers presenting a Melan-A/Mart-1 peptide …
2001
MHC class I tetramers containing peptide epitopes are sensitive tools for detecting antigen-specific CD8(+) T-cell responses. We demonstrate here that binding of HLA-A2 tetramers to CD8(+) T cells specific for the melanoma-associated antigen Melan-A/MART-1 can be fine-tuned by altering either the bound peptide epitope or residues in the alpha 3 domain of HLA-A2, which is important for CD8 binding. Antigen-specific T cells expressing high levels of CD8 could be detected using HLA-A2 tetramers containing the peptide AAGIGILTV, an epitope which is naturally processed and presented from Melan-A/MART-1. In contrast, low CD8-expressing, antigen-specific T cells could be detected efficiently only …