Biomaterial Database

A serine phosphatase is involved in CD2-mediated activation of human T lymphocytes and natural killer cells. 1991

Y Samstag, and A Bader, and S C Meuer

Abteilung Angewandte Immunologie, Deutsches Krebsforschungszentrum, Heidelberg, FRG.

We investigated early activation events after T cell triggering via the Ag receptor (TCR/CD3) complex as compared to activation via the CD2 surface molecule. To this end, resting peripheral human T lymphocytes were preincubated with 32P-orthophosphate and subsequently exposed to mitogenic mAb directed at either TCR/CD3 or CD2 for varying time periods. Cells were lysed and postnuclear lysates subjected to two-dimensional-gel electrophoresis (IEF and SDS-PAGE). As early as 10 min after stimulation through CD2, dephosphorylation of a cytosolic 19-kDa protein was observed. In contrast, this protein remained phosphorylated in unstimulated as well as CD3 activated T cells. Phosphoprotein (pp) 19 dephosphorylation was transient because, at later time points (2-4 h) after CD2 triggering, this protein was phosphorylated again. Phosphoaminoacid analysis indicated that pp19 is dephosphorylated on serine residues. Identical results were obtained using a CD2+ but TCR/CD3- human NK cell clone indicating that pp19 dephosphorylation occurs independent of surface expression of a TCR/CD3 complex. These data show that, in addition to protein phosphorylation events, serine dephosphorylation is involved in T cell triggering. More important, a selective signaling mechanism appears to be linked to T cell activation through the CD2 pathway.

UI	MeSH Term	Description	Entries
D007371	Interferon-gamma	The major interferon produced by mitogenically or antigenically stimulated LYMPHOCYTES. It is structurally different from TYPE I INTERFERON and its major activity is immunoregulation. It has been implicated in the expression of CLASS II HISTOCOMPATIBILITY ANTIGENS in cells that do not normally produce them, leading to AUTOIMMUNE DISEASES.	Interferon Type II,Interferon, Immune,gamma-Interferon,Interferon, gamma,Type II Interferon,Immune Interferon,Interferon, Type II
D007694	Killer Cells, Natural	Bone marrow-derived lymphocytes that possess cytotoxic properties, classically directed against transformed and virus-infected cells. Unlike T CELLS; and B CELLS; NK CELLS are not antigen specific. The cytotoxicity of natural killer cells is determined by the collective signaling of an array of inhibitory and stimulatory CELL SURFACE RECEPTORS. A subset of T-LYMPHOCYTES referred to as NATURAL KILLER T CELLS shares some of the properties of this cell type.	NK Cells,Natural Killer Cells,Cell, NK,Cell, Natural Killer,Cells, NK,Cells, Natural Killer,Killer Cell, Natural,NK Cell,Natural Killer Cell
D008213	Lymphocyte Activation	Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.	Blast Transformation,Blastogenesis,Lymphoblast Transformation,Lymphocyte Stimulation,Lymphocyte Transformation,Transformation, Blast,Transformation, Lymphoblast,Transformation, Lymphocyte,Activation, Lymphocyte,Stimulation, Lymphocyte
D010749	Phosphoprotein Phosphatases	A group of enzymes removing the SERINE- or THREONINE-bound phosphate groups from a wide range of phosphoproteins, including a number of enzymes which have been phosphorylated under the action of a kinase. (Enzyme Nomenclature, 1992)	Phosphoprotein Phosphatase,Phosphoprotein Phosphohydrolase,Protein Phosphatase,Protein Phosphatases,Casein Phosphatase,Ecto-Phosphoprotein Phosphatase,Nuclear Protein Phosphatase,Phosphohistone Phosphatase,Phosphoprotein Phosphatase-2C,Phosphoseryl-Protein Phosphatase,Protein Phosphatase C,Protein Phosphatase C-I,Protein Phosphatase C-II,Protein Phosphatase H-II,Protein-Serine-Threonine Phosphatase,Protein-Threonine Phosphatase,Serine-Threonine Phosphatase,Threonine Phosphatase,Ecto Phosphoprotein Phosphatase,Phosphatase C, Protein,Phosphatase C-I, Protein,Phosphatase C-II, Protein,Phosphatase H-II, Protein,Phosphatase, Casein,Phosphatase, Ecto-Phosphoprotein,Phosphatase, Nuclear Protein,Phosphatase, Phosphohistone,Phosphatase, Phosphoprotein,Phosphatase, Phosphoseryl-Protein,Phosphatase, Protein,Phosphatase, Protein-Serine-Threonine,Phosphatase, Protein-Threonine,Phosphatase, Serine-Threonine,Phosphatase, Threonine,Phosphatase-2C, Phosphoprotein,Phosphatases, Phosphoprotein,Phosphatases, Protein,Phosphohydrolase, Phosphoprotein,Phosphoprotein Phosphatase 2C,Phosphoseryl Protein Phosphatase,Protein Phosphatase C I,Protein Phosphatase C II,Protein Phosphatase H II,Protein Phosphatase, Nuclear,Protein Serine Threonine Phosphatase,Protein Threonine Phosphatase,Serine Threonine Phosphatase
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D011948	Receptors, Antigen, T-Cell	Molecules on the surface of T-lymphocytes that recognize and combine with antigens. The receptors are non-covalently associated with a complex of several polypeptides collectively called CD3 antigens (CD3 COMPLEX). Recognition of foreign antigen and the major histocompatibility complex is accomplished by a single heterodimeric antigen-receptor structure, composed of either alpha-beta (RECEPTORS, ANTIGEN, T-CELL, ALPHA-BETA) or gamma-delta (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA) chains.	Antigen Receptors, T-Cell,T-Cell Receptors,Receptors, T-Cell Antigen,T-Cell Antigen Receptor,T-Cell Receptor,Antigen Receptor, T-Cell,Antigen Receptors, T Cell,Receptor, T-Cell,Receptor, T-Cell Antigen,Receptors, T Cell Antigen,Receptors, T-Cell,T Cell Antigen Receptor,T Cell Receptor,T Cell Receptors,T-Cell Antigen Receptors
D011971	Receptors, Immunologic	Cell surface molecules on cells of the immune system that specifically bind surface molecules or messenger molecules and trigger changes in the behavior of cells. Although these receptors were first identified in the immune system, many have important functions elsewhere.	Immunologic Receptors,Immunologic Receptor,Immunological Receptors,Receptor, Immunologic,Receptors, Immunological
D004988	Ethers, Cyclic	Compounds of the general formula R-O-R arranged in a ring or crown formation.	Cyclic Ether,Cyclic Ethers,Ether, Cyclic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000911	Antibodies, Monoclonal	Antibodies produced by a single clone of cells.	Monoclonal Antibodies,Monoclonal Antibody,Antibody, Monoclonal