Phorbol esters regulate CD2- and CD3-mediated calcium responses in peripheral blood-derived human T cells.
The purpose of the present study was to examine the effect of protein kinase C (pkC) activation on calcium responses generated through the CD3 and CD2 Ag in both normal peripheral blood-derived T lymphocytes and the leukemic T cell line Jurkat. The data reveal a major difference with respect to the regulation of receptor-mediated calcium responses in these two cells. Thus, the pkC activator phorbol-12,13-dibutyrate (Pdbu) enhances calcium responses induced via CD3 and CD2 molecules in normal T cells by accelerating the rate of elevation of intracellular calcium levels and increasing the maximum change in calcium concentration achieved. In contrast, Pdbu inhibits both CD3- and CD2-induced calcium responses in Jurkat cells. Pdbu does not influence calcium responses generated by the guanine nucleotide-binding protein activator, aluminium fluoride, indicating that the effect of pkC occurs at a point proximal to a guanine nucleotide-binding protein regulation of T cell calcium responses.
Cantrell
D A
DA
Lymphocyte Activation Laboratory, Imperial Cancer Research Fund, London, UK.
Lucas
S C
SC
Ward
S
S
Westwick
J
J
Gullberg
M
M
D000535:Aluminum / Q000494:pharmacology; D017607:Aluminum Compounds; D000945:Antigens, Differentiation, T-Lymphocyte / Q000502:physiology*; D018801:CD2 Antigens; D017252:CD3 Complex; D002118:Calcium / Q000378:metabolism* / Q000502:physiology; D002460:Cell Line; D005459:Fluorides / Q000494:pharmacology; D006801:Humans; D015458:Leukemia, T-Cell / Q000276:immunology / Q000378:metabolism; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D010703:Phorbol Esters / Q000494:pharmacology*; D011493:Protein Kinase C / Q000502:physiology; D011948:Receptors, Antigen, T-Cell / Q000502:physiology*; D011971:Receptors, Immunologic / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects; D013601:T-Lymphocytes / Q000187:drug effects* / Q000201:enzymology / Q000502:physiology
D017607:Aluminum Compounds; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D017252:CD3 Complex; D010703:Phorbol Esters; D011948:Receptors, Antigen, T-Cell; D011971:Receptors, Immunologic; D015240:Phorbol 12,13-Dibutyrate; D000535:Aluminum; D011493:Protein Kinase C; D005459:Fluorides; D002118:Calcium; C032311:aluminum fluoride