057 Regulation of lipid-specific T cell activation in human skin

Specific cutaneous manifestations in adult T cell leukemia/lymphoma

Background and aim: Adult T cell leukemia/lymphoma (ATLL) is an aggresive malignancy which may occur in human T lymphotropic virus1(HTLV1) infected persons. HTLV1 is endemic in Khorasan with prevalence of 2.3% in general population. Since specific cutaneous manifestations of lymphoma may occur in a significant number of patients, we studied ATLL patients in Mashhad.Mate...

Negative regulation of T-cell receptor activation by the cAMP-PKA-Csk signalling pathway in T-cell lipid rafts.

Spatial organization of signal proteins in specialized cholesterol and glycosphingolipid-enriched microdomains (lipid rafts) provide specificity in lymphocyte signalling. Src kinases associate with lipid rafts on the basis of their dual acylation in the N-terminus and initiate T cell signalling. The immunomodulatory signal enzyme protein kinase A (PKA) is a serine/threonine kinase that controls...

Regulation of T cell activation by Hypoxia

Negative regulation of T cell activation.

T cell activation is negatively regulated by cytotoxic T lymphocyte antigen 4 (CTLA-4) and the killer cell inhibitory receptors. Endocytosis and signaling of CTLA-4 are regulated by tyrosine phosphorylation. While T cell activation is mediated by phosphorylation of immunoreceptor tyrosine-based activation motifs and tyrosine kinases, inhibitory signals are delivered by tyrosine phosphatases. Un...

Phosphorylation-dependent regulation of T-cell activation by PAG/Cbp, a lipid raft-associated transmembrane adaptor.

PAG/Cbp (hereafter named PAG) is a transmembrane adaptor molecule found in lipid rafts. In resting human T cells, PAG is tyrosine phosphorylated and associated with Csk, an inhibitor of Src-related protein tyrosine kinases. These modifications are rapidly lost in response to T-cell receptor (TCR) stimulation. Overexpression of PAG was reported to inhibit TCR-mediated responses in Jurkat T cells...