Delineation of the Role of a Na+/Ca2+ Exchanger in Regulating Intracellular Ca2+ in T Cells
| Autor: | Edward J. Cragoe, Mary C. Wacholtz, Peter E. Lipsky |
|---|---|
| Rok vydání: | 1993 |
| Předmět: |
CD3 Complex
T-Lymphocytes T cell Sodium Bepridil Immunology Mitosis chemistry.chemical_element Lithium Calcium Biology Lymphocyte Activation Jurkat cells Sodium-Calcium Exchanger Cell Line Amiloride medicine Extracellular Humans Na+/K+-ATPase Inositol phosphate Cells Cultured chemistry.chemical_classification Antibodies Monoclonal medicine.anatomical_structure chemistry Biochemistry Biophysics Carrier Proteins Intracellular |
| Zdroj: | Cellular Immunology. 147:95-109 |
| ISSN: | 0008-8749 |
| Popis: | One of the metabolic events that results from ligation of the CD3-TCR is an increase in [Ca2+]i. The mechanisms that generate this rise in [Ca2+]i are poorly understood, but involve mobilization of intracellular Ca2+ stores and the movement of extracellular Ca2+ into the cell. To examine the role of Na+/Ca2+ exchange in the increase in [Ca2+]i after CD3-TCR engagement, the effects of specific inhibitors of Na+/Ca2+ exchange, DCB, CBDMB, and bepridil, were examined. Inhibitors of Na+/Ca2+ exchange suppressed IL2 production and the rise in [Ca2+]i in Jurkat cells stimulated by anti-CD3 mAb. Mobilization of intracellular Ca2+ stores and mitogen-stimulated inositol phosphate production were not inhibited by these agents. Inhibitors of Na+/Ca2+ exchange also inhibited mitogen responses of normal T cells and the sustained increase in [Ca2+]i resulting from cross-linking class I MHC molecules, addition of PHA, or anti-CD3 mAb. Additional evidence for an important role of a Na+/Ca2+ exchanger in generating increases in [Ca2+]i after CD3 ligation was the finding that replacing extracellular Na+ with Li+, that cannot be transported by the Na+/Ca2+ exchanger, nearly abrogated the rise in [Ca2+]i induced by cross-linking CD3. These results are consistent with the conclusion that a Na+/Ca2+ exchanger is important in regulating changes in [Ca2+]i that are critical for T cell activation. |
| Databáze: | OpenAIRE |
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