title: IL-4 regulation of a protein kinase C independent pathway for the generation of alpha CD3-induced activated killer cells.
abstract: alpha CD3 induced the generation of activated killer cells from resting T cells. Pretreatment of the splenic responders with PMA, a phorbol ester, depleted protein kinase C and induced unresponsiveness to the generation of alpha CD3-induced activated killer (CD3-AK) cells. Addition of exogenous IL-4 (1 U/ml) restored the cytotoxic response, with the maximal effect achieved with 30 to 100 U/ml. The phenotypes of CD3-AK cells maintained in IL-2 or in IL-4, with or without PMA, were the same: Thy1+ and CD8+. These results were reproduced with purified T cells and purified CD8+ cells, indicating that both the effectors and precursors were CD8+ cells and IL-4 had a selective effect to upregulate the CD8+ cells. Similar results were obtained by using SSP (staurosporine), another PKC inhibitor. At 2 days prior to testing, switching the lymphokine added to 2-week PMA- and IL-2-maintained CD3-AK cells reversed their cytolytic activity: switching from IL-2 to IL-4 restored cytolytic activity, and switching from IL-4 to IL-2 reduced cytolytic activity. The cytolytic activity of these CD3-AK cells correlated with their ability to produce BLT-esterase. In the absence of PMA, CD3-AK cells cultured in either IL-2 or IL-4 were cytolytic and contained high levels of BLT-esterase. In contrast, in the presence of PMA, only the IL-4-maintained CD3-AK cells were cytolytic and produced significant amounts of BLT-esterase. The effect of IL-4 was abrogated by the alpha IL-4 antibody 11B11, which reduced the cytolytic activity of CD3-AK and the ability to produce BLT-esterase. The requirement of IL-2 was less stringent and its major role appeared to be maintaining the cell growth. These findings indicate that IL-4 may participate in the regulation of a PKC-independent pathway for the generation of CD3-AK cells by regulating the production of cytolytic granules.
authors.affiliation: Division of Cancer Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892.
authors.forename: C C
authors.initials: CC
authors.lastname: Ting
authors.forename: M E
authors.initials: ME
authors.lastname: Hargrove
mesh_terms: D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D000906:Antibodies / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology*; D017252:CD3 Complex; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured / Q000187:drug effects; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D005260:Female; D053804:Granzymes; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology*; D015979:Killer Cells, Lymphokine-Activated / Q000187:drug effects / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D011493:Protein Kinase C / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology*; D012697:Serine Endopeptidases / Q000032:analysis; D013154:Spleen / Q000166:cytology; D019311:Staurosporine; D013602:T-Lymphocytes, Cytotoxic / Q000187:drug effects / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014407:Tumor Cells, Cultured / Q000276:immunology
chemical_list: D000470:Alkaloids; D000906:Antibodies; D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D007376:Interleukin-2; D011948:Receptors, Antigen, T-Cell; D015847:Interleukin-4; D011493:Protein Kinase C; D053804:Granzymes; D012697:Serine Endopeptidases; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate