A variant of severe combined immunodeficiency syndrome (SCID) with a selective inability to produce CD8 single positive T cells and a signal transduction defect in peripheral CD4+ cells has recently been shown to be the result of mutations in the ZAP-70 gene. T cell receptor (TCR) signaling requires the association of the ZAP-70 protein tyrosine kinase with the TCR complex. Human T cell leukemi...

We transduced chronic lymphocytic leukemia (CLL) cells lacking ZAP-70 with vectors encoding ZAP-70 or various mutant forms of ZAP-70 and monitored the response of transduced CLL cells to treatment with F(ab)(2) anti-IgM (anti-mu). CLL cells made to express ZAP-70, a kinase-defective ZAP-70 (ZAP-70-KA(369)), or a ZAP-70 unable to bind c-Cbl (ZAP-YF(292)) experienced greater intracellular calcium...

The nonreceptor protein tyrosine kinase ZAP-70 is a critical enzyme required for successful T lymphocyte activation. After antigenic stimulation, ZAP-70 rapidly associates with T cell receptor (TCR) subunits. The kinetics of its translocation to the cell surface, the properties of its specific interaction with the TCR z chain expressed as a chimeric protein (TT z and T zz ), and its mobility in...

T cell receptor (TCR) signaling involves CD4/CD8-p56lck recruitment of ZAP-70 to the TCR receptor, ZAP-70 phosphorylation of LAT that is followed by LAT recruitment of the GADS-SLP-76 complex. Back regulation of ZAP-70 by SLP-76 has not been documented. In this paper, we show that anti-CD3 induced ZAP-70 cluster formation is significantly reduced in the absence of SLP-76 (i.e., J14 cells) and i...

Our aim was to assess the inter links of the markers CD38 and ZAP-70 based on our materials, the attitude according to the disease stage, and to document which of them had leading meaning for prognosis and treatmend of the disease. In our study we have used flow cytometry for detection CD38 and ZAP-70+ markers expression. (58 patients to assessments their prognostic value in сhronic lymphocytic...

BACKGROUND Up to now, the immune status of chronic lymphocytic leukemia (CLL) patients in association with the expression of zeta-chain-associated protein kinase 70 (ZAP-70) in leukemic cells has not been evaluated. AIM The aim of this work was the study of the peripheral blood (PB) T-lymphocyte phenotypes in ZAP-70-positive (ZAP-70(+)) and ZAP-70-negative (ZAP-70(-)) untreated patients with ...

The nonreceptor protein tyrosine kinase ZAP-70 is a critical enzyme required for successful T lymphocyte activation. After antigenic stimulation, ZAP-70 rapidly associates with T cell receptor (TCR) subunits. The kinetics of its translocation to the cell surface, the properties of its specific interaction with the TCRzeta chain expressed as a chimeric protein (TTzeta and Tzetazeta), and its mob...

Oxidative stress in T cells induces signaling events similar to those initiated by T cell antigen receptor engagement, including tyrosine phosphorylation and activation of the critical protein-tyrosine kinase ZAP-70. Distal signaling events such as the activation of mitogen-activated protein kinases and downstream transcription factors are also initiated by oxidative stimuli. In this study P116...

BACKGROUND Chronic lymphocytic leukaemia (CLL) is a heterogeneous disease; many patients never need treatment, whereas some have poor outcomes. New treatments, which can induce complete remissions, allow patients with poor outlook to be treated while they are still asymptomatic. Whether or not the IgVH gene is mutated is the best predictor of clinical outcome, but this assay is unsuited to the ...

PURPOSE The ZAP-70 gene is normally expressed in T and natural killer cells, where it is required for the T-cell receptor (TCR) signaling. More recently, it has been described that ZAP-70 contributes to the B-cell development at early stages of B-cell differentiation in mice. The purpose was to investigate the presence of ZAP-70 in normal pro/pre B cells and mature B cells and in tumoral cells ...