Search results for "CD"
showing 10 items of 4072 documents
Value of bone marrow biopsy in the diagnosis of essential thrombocythemia.
2004
Background and Objectives. Essential thrombocythemia (ET) is a Philadelphia chromosome-negative chronic myeloproliferative disorder (CMPD) whose diagnosis, according to the Polycythemia Vera Study Group (PVSG) criteria, does not include histopathological data. The new WHO classification of CMPD has supplied new diagnostic guidelines which highlight the value of histopathology and facilitate a more precise differentiation of ET from reactive conditions and other CMPD. Design and Methods. Bone marrow biopsies from 142 adult patients diagnosed with ET according to PVSG criteria were evaluated using the new WHO classification. Megakaryocyte morphology and arrangement, amount of fibrosis and a c…
A double-negative (IgD−CD27−) B cell population is increased in the peripheral blood of elderly people
2009
The T cell branch of the immune system has been extensively studied in the elderly and it is known that the elderly have impaired immune function, mainly due to the chronic antigenic load that ultimately causes shrinkage of the T cell repertoire and filling of the immunologic space with memory T cells. In the present paper, we describe the IgD(-)CD27(-) double-negative B cell population which (as we have recently described) is higher in the elderly. Most of these cells were IgG(+). Evaluation of the telomere length and expression of the ABCB1 transporter and anti-apoptotic molecule, Bcl2, shows that they have the markers of memory B cells. We also show that these cells do not act as antigen…
Study of T-cell activation in Type I diabetic patients and pre-Type I diabetic subjects by cytometric analysis: Antigen expression defectin vitro
1993
In Type I diabetes the observation of a decreased release of interleukin-2 (IL-2) and soluble IL-2 receptors by means of stimulated lymphocytes in vitro indicates that a primary immunoregulatory defect may be involved. To confirm this hypothesis we investigated the T-cell activation trend, evaluating the surface expression of IL-2 receptor (CD25), transferrin (CD71), HLA class II (DR), and CD69 phenotypes after in vitro stimulation with phytohemagglutinin (PHA; 1 and 10 micrograms/ml) and concanavalin A (12.5 micrograms/ml) in six newly diagnosed Type I diabetics and six islet cell- and insulin autoantibody-positive first-degree relatives. As controls were studied six long-standing Type I d…
T cell receptor gene rearrangements of T lymphocytes infiltrating the liver in chronic active hepatitis B and primary biliary cirrhosis (PBC): Oligoc…
1990
Immunological events are involved in the pathophysiology of chronic active hepatitis as indicated from the accumulation of T lymphocytes at the site of tissue damage. We generated T cell clones from liver biopsies of 3 patients with chronic active hepatitis B and 2 patients with primary biliary cirrhosis. These T cell clones (n = 84) were analyzed by means of T cell receptor (TcR) beta gene rearrangements to determine whether the infiltrate consists of a polyclonal or oligoclonal T cell population. The vast majority (62 of 64) of T cell clones from three different patients with chronic active hepatitis B showed no identical rearrangements of the TcR beta chain genes. In marked contrast, in …
CXCR5 identifies a subset of Vγ9Vδ2 T cells which secrete IL-4 and IL-10 and help B cells for antibody production
2006
Abstract Vγ9Vδ2 T lymphocytes recognize nonpeptidic Ags and mount effector functions in cellular immune responses against microorganisms and tumors, but little is known about their role in Ab-mediated immune responses. We show here that expression of CXCR5 identifies a unique subset of Vγ9Vδ2 T cells which express the costimulatory molecules ICOS and CD40L, secrete IL-2, IL-4, and IL-10 and help B cells for Ab production. These properties portray CXCR5+Vγ9Vδ2 T cells as a distinct memory T cell subset with B cell helper function.
T-cell activation in HLA-B8,DR3-positive individuals early antigen expression defect in vitro
1995
The HLA-B8, DR3 haplotype is overrepresented in several autoimmune diseases, implying that genes predisposing to these disorders are linked to this haplotype. In the patients affected by these diseases, as well as in healthy HLA-B8, DR3 individuals, various dysfunctions reflecting an impairment of T-cell activation have been found. To better characterize T-cell impairment of HLA-B8, DR3-positive healthy individuals, we analyzed the surface expression of early (CD69) and late (CD71) activation phenotypes. MNC cultures were stimulated with PHA and used for T-cell phenotyping by flow cytometry analysis. The results showed that the percentage of CD69+ T cells was significantly decreased in MNC …
The 9-O-acetylated disialosyl carbohydrate sequence of CDw60 is a marker on activated human B lymphocytes
1998
Gangliosides with a terminal 9-O-acetylated disialosyl group (CDw60 structures) show a restricted surface expression on human leukocytes. Hithereto, they have only been detected on subpopulations of human T lymphocytes. Using the defined CDw60 antibody UM4D4 and two new antibodies with preferential CDw60 activities, F6 and Z17, we demonstrate for the first time that CDw60 is an activation marker on human B lymphocytes. In vitro phorbol ester-stimulated human peripheral blood B lymphocytes as well as in vivo activated tonsillar B lymphocytes became CDw60 positive. CDw60 expression of these cells exceeds that of resting and activated T-lymphocytes.
Low bcl-2 expression and increased spontaneous apoptosis in T-lymphocytes from newly-diagnosed IDDM patients.
1995
The bcl-2 gene product has been shown to regulate apoptotic cell death, and its dysregulation has been shown to induce several abnormalities in the immune system. No data exist regarding bcl-2 expression in autoimmune diseases, such as human insulin-dependent diabetes mellitus (IDDM). We investigated bcl-2 protein expression by testing T lymphocytes from 15 newly-diagnosed (3 weeks) IDDM patients in comparison to 10 age-matched control subjects. The expression of bcl-2 on CD3+ lymphocyte subsets was investigated after membrane permeabilization by two- or three-colour immunofluorescence. When the percentage and mean fluorescence intensity (MFI) of bcl-2+/CD3+ cells from normal individuals an…
Newly diagnosed depression is associated with increased beta-thromboglobulin levels and increased expression of platelet activation markers and plate…
2013
Abstract Background Inflammation plays a key role in atherosclerotic disease. Up until now only limited evidence exists on the mechanism of cardiovascular complications in patients with depression. In addition depression was also linked to an increase in cardiovascular mortality. The present study was designed to evaluate the extent of platelet activation and platelet-derived markers of atherosclerotic disease in patients with newly diagnosed depression. Methods This study used whole blood aggregometry, flow cytometry and ELISA to investigate platelet CD62P (P-selectin) expression and atherosclerotic markers (CD40, CD40L) as well as serum platelet factor 4 (PF-4) and beta-thromboglobulin (β…
Spontaneous echo contrast caused by platelet and leukocyte aggregates?
2001
Background and Purpose —Spontaneous echocardiographic contrast (SEC) is correlated to clinical thromboembolic events. We sought to determine the origin of SEC by utilizing direct analysis of left atrial blood. Methods —We examined the blood of 13 patients with and 19 without SEC. Blood samples were taken from the femoral vein and artery and from the right and left atria after transseptal puncture. Samples were incubated with fluorescence-labeled antibodies directed against the platelet (CD41a-PE, CD42b-PE, and CD62p-FITC) and leukocyte membrane epitopes (CD45-APC and CD14-FITC). The expressed epitopes were analyzed by dual laser flow cytometry immediately after blood withdrawal. Results —I…