Search results for " CD"
showing 10 items of 587 documents
Probable disseminated Mycobacterium abscessus subspecies bolletii infection in a patient with idiopathic CD4+ T lymphocytopenia: a case report.
2012
Abstract Introduction Rapidly growing mycobacteria are opportunistic pathogens in patients with underlying risk factors. Mycobacterium abscessus subsp. bolletii is a newly recognized member of rapidly growing mycobacteria, isolated from respiratory tract and cutaneous infections. Case presentation We describe a case of chronic disseminated infection caused by M. abscessus subsp. bolletii in a 38-year-old Sri Lankan man with idiopathic CD4+ T lymphocytopenia. Idiopathic CD4+ T lymphocytopenia is a rare cause of immunodysfunction that, similar to human immunodeficiency virus infection, causes a depletion of CD4+ T lymphocytes. M. abscessus subsp. bolletii infection was diagnosed by culture is…
Selective Uptake of Cylindrical Poly(2-Oxazoline) Brush-AntiDEC205 Antibody-OVA Antigen Conjugates into DEC-Positive Dendritic Cells and Subsequent T…
2014
To achieve specific cell targeting by various receptors for oligosaccharides or antibodies, a carrier must not be taken up by any of the very many different cells and needs functional groups prone to clean conjugation chemistry to derive well-defined structures with a high biological specificity. A polymeric nanocarrier is presented that consists of a cylindrical brush polymer with poly-2-oxazoline side chains carrying an azide functional group on each of the many side chain ends. After click conjugation of dye and an anti-DEC205 antibody to the periphery of the cylindrical brush polymer, antibody-mediated specific binding and uptake into DEC205(+) -positive mouse bone marrow-derived dendri…
Suppressor activity of anergic T cells induced by IL-10-treated human dendritic cells: association with IL-2- and CTLA-4-dependent G1 arrest of the c…
2003
We have previously shown that human IL-10-treated dendritic cells (DC) induce an antigen-specific anergy in CD4+ T lymphocytes. These anergic T cells are characterized by an inhibited proliferation, a reduced production of IL-2, and additionally display antigen-specific suppressor activity. In this study we investigated the mechanisms underlying the anergic state and regulatory function of these T cells. We did not observe enhanced rates of programmed cell death of anergic CD4+ suppressor T cells compared to T cells stimulated with mature DC. Cell cycle analysis by DNA staining and Western blot experiments revealed an arrest of anergic CD4+ T suppressor cells in the G1 phase. High levels of…
Tuning tumor-specific T-cell activation: a matter of costimulation?
2002
Abstract The stimulation of a specific antitumor immune response, involving the recruitment of T cells and induction of T-cell effector functions, is an attractive possibility for cancer immunotherapy. In the past few years, advances in our understanding of the mechanisms of T-cell activation and costimulation have provided the basis for strategies to enhance antitumor immunity and break tolerance. These strategies include the equipment of tumor cells with costimulatory molecules such as B7, blockade of inhibitory signals on T cells (e.g. through cytotoxic T-lymphocyte antigen 4) and grafting of T cells with antigen-triggered, recombinant costimulatory receptors. Combining antigen-triggered…
Identification and Functional Characterization of Human Cd4+Cd25+ T Cells with Regulatory Properties Isolated from Peripheral Blood
2001
A subpopulation of peripheral human CD4(+)CD25(+) T cells that expresses CD45RO, histocompatibility leukocyte antigen DR, and intracellular cytotoxic T lymphocyte-associated antigen (CTLA) 4 does not expand after stimulation and markedly suppresses the expansion of conventional T cells in a contact-dependent manner. After activation, CD4(+)CD25(+) T cells express CTLA-4 on the surface detectable for several weeks. These cells show a G1/G0 cell cycle arrest and no production of interleukin (IL)-2, IL-4, or interferon (IFN)-gamma on either protein or mRNA levels. The anergic state of CD4(+)CD25(+) T cells is not reversible by the addition of anti-CD28, anti-CTLA-4, anti-transforming growth fa…
Human CD4+CD25+ T cells derived from the majority of atopic donors are able to suppress TH1 and TH2 cytokine production
2003
Abstract Background: Recently, it has been established that CD4 + CD25 + T cells with regulatory capacity are present in human peripheral blood, inhibiting allogeneic proliferation and cytokine production of preactivated CD4 + CD25 − respond-er T cells. Objective: The aim of this study was to analyze in an allergen-specific setting whether such regulatory CD4 + CD25 + T cells also exist and function normally in atopic individuals, especially concerning the inhibition of T H 2 cytokines. Methods: For this purpose, CD4 + CD25 − or CD4 + CD25 + T cells from donors allergic to grass or birch pollen (mainly with rhinitis) or from healthy nonatopic donors were stimulated in the presence of autolo…
Over 30% of patients with splenic marginal zone lymphoma express the same immunoglobulin heavy variable gene: ontogenetic implications.
2012
We performed an immunogenetic analysis of 345 IGHV-IGHD-IGHJ rearrangements from 337 cases with primary splenic small B-cell lymphomas of marginal-zone origin. Three immunoglobulin (IG) heavy variable (IGHV) genes accounted for 45.8% of the cases (IGHV1-2, 24.9%; IGHV4-34, 12.8%; IGHV3-23, 8.1%). Particularly for the IGHV1-2 gene, strong biases were evident regarding utilization of different alleles, with 79/86 rearrangements (92%) using allele *04. Among cases more stringently classified as splenic marginal-zone lymphoma (SMZL) thanks to the availability of splenic histopathological specimens, the frequency of IGHV1-2*04 peaked at 31%. The IGHV1-2*04 rearrangements carried significantly lo…
The Challenge of Using CB-HSCs As Source for Gene Therapy: Lentiviral Vector Transduction, Phenotypic Characterization and Global Gene Expression Pro…
2015
Abstract Introduction: Genetic modification of autologous hematopoietic stem and progenitor cells (HSPC) is a promising clinical intervention to cure inherited monogenic diseases. Successful gene therapy trials have already been conducted using CD34+ cells from bone marrow and from mobilized peripheral blood. In this regard, cord blood (CB) represents an attractive source of HSCs due to its high concentration of high proliferative HSPC and increased susceptibility to be transduced by lentiviral vectors. Unfortunately, the major disadvantage is the limited number of HSC in the CB collection. Consequently, ex-vivo expansion of CB-HSC is desirable to extend clinical applications. Purposes: To …
Inhibition of human allergic T-helper type 2 immune responses by induced regulatory T cells requires the combination of interleukin-10-treated dendri…
2006
Summary Background In grass pollen-allergic individuals, T cell anergy can be induced by IL-10-treated dendritic cells (IL-10-DC) resulting in the suppression of T helper type 1 (Th1) as well as Th2 cells. This study was performed to analyse whether such IL-10-DC-treated T cells are able to act as regulatory T cells (Treg) suppressing the function of other T cells in the periphery. As transforming growth factor (TGF)-β is also a potential inducer of Treg, we additionally analysed the inhibitory capacity of TGF-β-treated T cells in this system. Materials and Methods Freshly isolated CD4+ or CD4+CD25− T cells from grass pollen-allergic donors were stimulated with autologous mature monocyte-de…
Human papillomavirus infection requires cell surface heparan sulfate.
2001
ABSTRACT Using pseudoinfection of cell lines, we demonstrate that cell surface heparan sulfate is required for infection by human papillomavirus type 16 (HPV-16) and HPV-33 pseudovirions. Pseudoinfection was inhibited by heparin but not dermatan or chondroitin sulfate, reduced by reducing the level of surface sulfation, and abolished by heparinase treatment. Carboxy-terminally deleted HPV-33 virus-like particles still bound efficiently to heparin. The kinetics of postattachment neutralization by antiserum or heparin indicated that pseudovirions were shifted on the cell surface from a heparin-sensitive into a heparin-resistant mode of binding, possibly involving a secondary receptor. Alpha-6…