title: Activation of human eosinophils by monokines and lymphokines: source and biochemical characteristics of the eosinophil cytotoxicity-enhancing activity produced by blood mononuclear cells.
abstract: We and others have previously reported that human blood mononuclear cells release in culture certain substances that enhance the capacity of purified human blood eosinophils to kill the antibody-coated larvae of Schistosoma mansoni. The present study shows that this eosinophil cytotoxicity-enhancing activity (ECEA) is released by monocytes and T lymphocytes. Monocytes produce ECEA in resting and in LPS-stimulated cultures; T lymphocytes release such activity when stimulated by mitogens such as concanavalin A. Furthermore, the human monocytic line U-937 also releases ECEA-like activity when stimulated by LPS. The enhancing activity produced by monocytes has been partially characterized: it is sensitive to proteolysis by trypsin, relatively heat stable, and associated with molecules that have an apparent molecular weight of 14,000 to 65,000 daltons and isoelectric points of 3.8-3.9, 4.2, 4.5, 4.8-4.9. This shows that while ECEA produced by monocytes is heterogeneous in size and charge, it is probably different from interleukin 1.
mesh_terms: D002850:Chromatography, Gel; D003208:Concanavalin A / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D004804:Eosinophils / Q000187:drug effects* / Q000276:immunology; D006801:Humans; D007525:Isoelectric Focusing; D008222:Lymphokines / Q000302:isolation & purification* / Q000494:pharmacology*; D009000:Monocytes / Q000276:immunology*; D015846:Monokines; D011506:Proteins / Q000494:pharmacology*; D012550:Schistosoma mansoni / Q000276:immunology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D008222:Lymphokines; D015846:Monokines; D011506:Proteins; C022227:eosinophil stimulating promoter; D003208:Concanavalin A; D013755:Tetradecanoylphorbol Acetate