title: Calcium signalling in T-lymphocytes.
abstract: Calcium signalling is essential for most of the biological T-cell activities, including in Th2 lymphocytes, a T-cell subset that produce interleukin 4, 5 and 13 and which is involved in allergic diseases. T-cell receptor engagement induces the production of inositol trisphosphate that binds to its receptor, releasing intracellular Ca(2+) stores. STIM in the endo (sarco) plasmic reticulum (ER/SR) is a Ca(2+) sensor that perceives the depletion of intracellular Ca(2+) stores, localizes near the cell membrane and allows the activation of ORAI, the main calcium channels at the cell membrane. However, other calcium channels at the membrane of intracellular compartments and at the cell membrane can also contribute to the TCR-driven intracellular Ca(2+) rise. Among them, voltage-dependent calcium (Ca(v)1) channels have been reported in several types of T-lymphocytes, although how they are gated in these non-excitable cells remains unsolved. We have shown that Cav1 channel expression was selectively up regulated in Th2 lymphocytes. In this review, we will discuss about the diversity of the Ca(2+) channels responsible for Ca(2+) homeostasis in the different cell subsets and the interactions between these molecules, which can account for the variety of the calcium responses depending upon the functions of effector T-cells.
authors.affiliation: INSERM U1043, Centre de Physiopathologie de Toulouse Purpan, France.
authors.forename: V
authors.initials: V
authors.lastname: Robert
authors.forename: E
authors.initials: E
authors.lastname: Triffaux
authors.forename: M
authors.initials: M
authors.lastname: Savignac
authors.forename: L
authors.initials: L
authors.lastname: Pelletier
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000378:metabolism; D020013:Calcium Signaling; D002462:Cell Membrane / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D013601:T-Lymphocytes / Q000378:metabolism*
chemical_list: D015220:Calcium Channels; D047908:Intracellular Signaling Peptides and Proteins; D002118:Calcium