Search results for " Differentiation"

IL-21 Regulates the Differentiation of a Human γδ T Cell Subset Equipped with B Cell Helper Activity

2012

Vγ9Vδ2 T lymphocytes recognize nonpeptidic antigens without presentation by MHC molecules and display pleiotropic features. Here we report that coculture of Vγ9Vδ2 cells with phosphoantigen and IL-21 leads to selective expression of the transcription repressor Bcl-6 and polarization toward a lymphocyte subset displaying features of follicular B-helper T (T(FH)) cells. T(FH) like Vγ9Vδ2 cells have a predominant central memory (CD27(+)CD45RA(-)) phenotype and express ICOS, CD40L and CXCR5. Upon antigen activation, they secrete IL-4, IL-10 and CXCL13, and provide B-cell help for antibody production in vitro. Our findings delineate a subset of human Vγ9Vδ2 lymphocytes, which, upon interaction w…

Facilitated Anion Transport Induces Hyperpolarization of the Cell Membrane That Triggers Differentiation and Cell Death in Cancer Stem Cells

2015

Facilitated anion transport potentially represents a powerful tool to modulate various cellular functions. However, research into the biological effects of small molecule anionophores is still at an early stage. Here we have used two potent anionophore molecules inspired in the structure of marine metabolites tambjamines to gain insight into the effect induced by these compounds at the cellular level. We show how active anionophores, capable of facilitating the transmembrane transport of chloride and bicarbonate in model phospholipid liposomes, induce acidification of the cytosol and hyperpolarization of plasma cell membranes. We demonstrate how this combined effect can be used against canc…

Macrophage Migration Inhibitory Factor Induces Inflammation and Predicts Spinal Progression in Ankylosing Spondylitis

2017

Objective: To investigate the role of macrophage migration inhibitory factor (MIF) in the pathogenesis of ankylosing spondylitis (AS). Methods: Patients who met the modified New York criteria for AS were recruited for the study. Healthy volunteers, rheumatoid arthritis patients, and osteoarthritis patients were included as controls. Based on the annual rate of increase in modified Stoke AS Spine Score (mSASSS), AS patients were classified as progressors or nonprogressors. MIF levels in serum and synovial fluid were quantitated by enzyme-linked immunosorbent assay. Predictors of AS progression were evaluated using logistic regression analysis. Immunohistochemical analysis of ileal tissue was…

Electromagnetic Sensitivity Analysis and Shape Optimization Using Method of Moments and Automatic Differentiation

2009

Sensitivity analysis is an important part of gradient-based optimization of electromagnetic devices. We demonstrate how sensitivity analysis can be incorporated into an existing in-house method of moments solver with a relatively small amount of labor by using a technique called automatic differentiation (AD). This approach enables us to obtain (geometrical) sensitivities of the discrete solution with accuracy up to numerical precision. We compare the assembly time and memory usage of the modified and original solvers. Moreover, we optimize the shape of a dipole antenna and the dimensions of a Yagi-Uda array using the presented AD technique, traditional response level finite difference sens…

Embryonic neural cell adhesion molecules on human natural killer cells

1989

The neural cell adhesion molecules (NCAM) are surface glycoproteins that were first described in brain tissue. NCAM mediate adhesion in a variety of cell-cell interactions. In the present study we show that the so-called "embryonic" NCAM, i.e., the highly polysialylated forms of these proteins, are expressed on natural killer cells and some CD3+ cells in man. Homotypic binding of NCAM, believed to be of importance for cell-cell adhesion in neural tissues, appears not to be essential for NK cell-mediated killing. Yet, NCAM might be involved in NK cell migration, homing or related functions.

Requirements for the growth of TH1 lymphocyte clones.

1990

Besides the signal generated in a T lymphocyte after triggering the T cell receptor (TcR), most lymphocytes need a "second signal" to become fully activated. The necessity and nature of the "second signal" differs between different types of T cells. At the level of CD4-positive T helper lymphocytes interleukin 1 (IL 1) serves as "second signal" for those of the TH2 subtype (IL4, 5, 6 producer) but not for those of the TH1 subtype (IL 2, IFN-gamma producer). This correlates with the absence of the IL 1 receptor at the surface of TH1 clones. We report herein the further purification of T cell stimulating factor (TSF), a soluble mediator involved in the proliferation of TH1 lymphocytes. A prep…

Different response of TH1 cells for stimulation with anti-CD3 antibodies.

1990

In this report, evidence is provided for a further subdivision of CD4+ T helper cell lines. The earlier definition of the TH1 and TH2 subtypes was confirmed by their differential response to interleukin (IL) 1. An additional subdivision of the TH1 subset was revealed when TH1 cell lines were costimulated with anti-CD3 antibodies and IL2. The IL2-induced proliferation of three of the resulting TH1 lines was blocked by anti-CD3 antibodies. By contrast, no such block was observed in a fourth TH1 cell line. In all four lines anti-CD3 triggering caused production of IL2. The block of proliferation was reversed neither by antigen-presenting cells nor by phorbol 12-myristate 13-acetate, a protein …

Depletion of alloreactive T cells via CD69: implications on antiviral, antileukemic and immunoregulatory T lymphocytes

2005

Selective depletion of alloreactive T cells from stem-cell allografts should abrogate graft-versus-host disease while preserving beneficial T cell specificities to facilitate engraftment and immune reconstitution. We therefore explored a refined immunomagnetic separation strategy to effectively deplete alloreactive donor lymphocytes expressing the activation antigen CD69 upon stimulation, and examined the retainment of antiviral, antileukemic, and immunoregulatory T cells. In addition to the CD69high T cell fraction, our studies retrieved two T cell subsets based on residual CD69 expression. Whereas, truly CD69(neg) cells were devoid of detectable alloresponses to original stimulators, CD69…

NF-ATp plays a prominent role in the transcriptional induction of Th2-type lymphokines

1997

Components of an antigen-/T cell receptor-independent pathway of lymphokine production

1991

The general way to induce the synthesis of lymphokines by T cells is the stimulation through the T cell receptor (TcR) complex which results in an increase of intracellular [Ca2+] and in the activation of a tyrosine kinase as well as of protein kinase C. Lymphokine production induced via the TcR is inhibited by the immunosuppressive drug cyclosporin A (CsA). However, an alternative pathway of lymphokine production exists. Several T lymphocyte clones can synthesize interferon-gamma (IFN-gamma), granulocyte-monocyte colony-stimulating factor, and small amounts of interleukin (IL3) when stimulated with syngeneic or allogeneic accessory cells (AC) plus IL2. In contrast to the TcR pathway the al…