Protein kinase C activity in activated human T-lymphocytes stimulated by interleukin-2.
Interleukin-2 and phorbol 12-myristate 13-acetate (PMA) are shown to induce DNA-synthesis in human T-lymphocytes activated with phytohaemagglutinin. However, whereas PMA induced a rapid and persistent translocation of protein kinase C from cytosol to particulate fraction, no translocation was observed upon stimulation with interleukin-2. Treatment with PMA for 72 h caused a slow down-regulation of protein kinase C activity to less than 10% of unstimulated T-lymphocytes and was mainly located in the particulate fraction. In contrast, stimulation with phytohaemagglutinin increased the total cellular protein kinase C activity by approx. 100% but with an unaltered subcellular distribution. However, interleukin-2-induced DNA synthesis in PMA- and phytohaemagglutinin-stimulated T-lymphocytes was comparable. Further, maximal DNA synthesis was shown to be dependent on the continuous presence of interleukin-2. These results indicate that interleukin-2-induced proliferation of activated human T-lymphocytes can occur without a translocation of protein kinase C from the cytosol to the particulate fraction and that interleukin-2 most likely functions as a progression factor.
Larsen
C S
CS
Department of Medicine and Infectious Diseases, Marselisborg Hospital, Aarhus C, Denmark.
Christiansen
N O
NO
Esmann
V
V
D002451:Cell Compartmentation; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D008213:Lymphocyte Activation; D011493:Protein Kinase C / Q000097:blood* / Q000378:metabolism; D013601:T-Lymphocytes / Q000201:enzymology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors
D007376:Interleukin-2; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate