Search results for "Lymphocytes"

Minimal Lesions of the Small Intestinal Mucosa: More than Morphology

2020

Minimal lesions of the small bowel are mucosal changes characterized by an increased number of intraepithelial lymphocytes (with or without crypt hyperplasia) and normal villous architecture. Such changes are associated with a wide spectrum of conditions, ranging from food intolerances to infections, and from drugs to immune diseases, with different clinical profiles and manifestations, which complicates the formulation of a differential diagnosis. Patient history, symptom evaluation, and histopathology are the diagnostic features needed to establish a correct diagnosis. Physicians should assist pathologists in formulating a precise morphological evaluation by taking well-oriented small int…

Synergistic effects of fluticasone propionate and salmeterol on in vitro T-cell activation and apoptosis in asthma

2004

Background In asthma T cells are characterized by an increased activation state and by reduced apoptosis. Objective Because the clinical efficacy of inhaled corticosteroids combined with long-acting β 2 -agonists has been widely demonstrated in asthma, we studied, in vitro , the effect of fluticasone propionate (FP) and salmeterol alone and in combination on the activation and apoptosis of peripheral blood T cells (PBTs), on the expression of phosphorylated nuclear factor κB inhibitor (IκBα), and on the nuclear translocation of glucocorticoid receptor (GR) in PBTs from asthmatic subjects. Methods Apoptosis was evaluated on the basis of annexin V binding, whereas the expression of caspases 8…

Repression of Cyclic Adenosine Monophosphate Upregulation Disarms and Expands Human Regulatory T Cells

2011

Abstract The main molecular mechanism of human regulatory T cell (Treg)-mediated suppression has not been elucidated. We show in this study that cAMP represents a key regulator of human Treg function. Repression of cAMP production by inhibition of adenylate cyclase activity or augmentation of cAMP degradation through ectopic expression of a cAMP-degrading phosphodiesterase greatly reduces the suppressive activity of human Treg in vitro and in a humanized mouse model in vivo. Notably, cAMP repression additionally abrogates the anergic state of human Treg, accompanied by nuclear translocation of NFATc1 and induction of its short isoform NFATc1/αA. Treg expanded under cAMP repression, however,…

Granulocyte-macrophage colony-stimulating factor-cultured bone marrow-derived macrophages reveal accessory cell function and synthesis of MHC class I…

1988

The antigen-mediated activation of a number of T cell clones by bone marrow (BM) cells cultivated in the presence of various colony-stimulating factor (CSF) preparations was investigated. BM macrophages (BMM phi) grown in L929 cell supernatant as a crude source of macrophage colony-stimulating factor (M-CSF) as well as BM cells propagated in the presence of recombinant M-CSF exhibited transient antigen presentation potential to some T cell clones, being maximal on day 7 and having declined to a low level by day 19 of in vitro culture. Treatment of these long-term-cultivated BMM phi populations with recombinant interferon-gamma (IFN-gamma) resulted in predominant antigen presentation capacit…

Retarded thymic involution and massive germinal center formation in NF-ATp-deficient mice.

1998

NF-ATp and NF-ATc are the most prominent nuclear NF-AT transcription factors in peripheral T lymphocytes. After T cell activation both factors bind to and control the promoters and enhancers of numerous lymphokine and receptor ligand genes. In order to define a specific role for NF-ATp in vivo we have inactivated the NF-ATp gene by gene targeting in mice. We show that NF-ATp deficiency leads to the accumulation of peripheral T cells with a “preactivated” phenotype, enhanced immune responses of T cells after secondary stimulation in vitro and severe defects in the proper termination of antigen responses, as shown by a reduced deletion of superantigen-reactive CD4+ T cells. These alterations …

Responses to self and non-self intestinal microflora in health and inflammatory bowel disease.

1997

Functional roles of the sweet taste receptor in oral and extraoral tissues

2014

International audience; Purpose of review: This review summarizes and discusses the current knowledge about the physiological roles of the sweet taste receptor in oral and extraoral tissues. Recent findings: The expression of a functional sweet taste receptor has been reported in numerous extragustatory tissues, including the gut, pancreas, bladder, brain and, more recently, bone and adipose tissues. In the gut, this receptor has been suggested to be involved in luminal glucose sensing, the release of some satiety hormones, the expression of glucose transporters, and the maintenance of glucose homeostasis. More recently, the sweet taste receptor was proposed to regulate adipogenesis and bon…

Diagnostic efficacy of the fluorometric determination of enzyme activity for Pompe disease from dried blood specimens compared with lymphocytes-possi…

2009

Pompe disease is a rare, autosomal-recessive disorder which results from a defect in the lysosomal enzyme acid alpha-glucosidase (GAA). The onset of this disease is highly variable, with infantile types being the most severe. Traditionally, lymphocytes, fibroblasts or muscle biopsies were necessary for enzyme activity measurement, because these materials do not express maltase-glucoamylase (MGA) that interferes with the assay. Recently, acarbose was found to inhibit MGA activity selectively, so that dried blood became accessible for GAA assessment.To evaluate the diagnostic efficacy of GAA measurement in dried blood specimens (DBSs) in comparison with lymphocytes. If DBSs provided reliable …

Adipose tissue lymphocytes: types and roles

2009

Besides adipocytes, specialized in lipid handling and involved in energy balance regulation, white adipose tissue (WAT) is mainly composed of other cell types among which lymphocytes represent a non-negligible proportion. Different types of lymphocytes (B, alphabetaT, gammadeltaT, NK and NKT) have been detected in WAT of rodents or humans, and vary in their relative proportion according to the fat pad anatomical location. The lymphocytes found in intra-abdominal, visceral fat pads seem representative of innate immunity, while those present in subcutaneous fat depots are part of adaptive immunity, at least in mice. Both the number and the activity of the different lymphocyte classes, except …

Comparative effects of UVA and UVB irradiation on the immune system of fish.

2000

Aquatic organisms can be harmed by the current levels of solar ultraviolet radiation. We have recently shown that exposure of fish to UVB irradiation alters the functioning of the fish immune system, but the effects of UVA radiation are unknown. The present study continues this work by characterizing UVA irradiation-induced immunological changes in fish. Roach, a cyprinid fish, were exposed to a single dose of either UVA (3.6 J/cm2) or UVB (0.5 J/cm2) irradiation. Both irradiations suppressed transiently mitogen-stimulated proliferation of blood lymphocytes. UVA, but not UVB, decreased hematocrit, plasma protein, and plasma immunoglobulin levels and increased the proportions of blood cells …