Immunological activities of RU-41740, a glycoproteic extract from Klebsiella pneumoniae. II.--Activation of macrophage cytotoxicity against tumour cells and production of a cytotoxic factor.
RU-41740, a glycoprotein extract from Klebsiella pneumoniae, is an immunomodulating agent with a broad spectrum of activities. It enhances several macrophage functions, including interleukin-1 (IL-1) secretion. Present data show that RU-41740 was able to promote murine macrophage cytotoxicity against tumour cells. A soluble cytotoxic factor (CF) was found in supernatants from macrophage cultures stimulated with RU-41740. These supernatants were shown to contain IL-1. CF was detected on L-929 cells sensitized by actinomycin D. CF was analysed on the basis of MW and pHi: after gel filtration on "Ultrogel Aca54", a single peak of CF was found in the range of 50-60 Kd and was then distinct from IL-1, which was eluted at 15 Kd. After chromatofocusing, CF was found in a narrow peak of pH 4.8. CF was detected in supernatants 2 h after macrophage stimulation by RU-41740, and its release was abolished by pretreatment of macrophages with cycloheximide (2 micrograms/ml). CF described here shares several properties with tumour necrosis factor (TNF).
D000818:Animals; D001426:Bacterial Proteins / Q000494:pharmacology*; D003513:Cycloheximide / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D005260:Female; D006023:Glycoproteins / Q000494:pharmacology; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D007375:Interleukin-1 / Q000378:metabolism; D007711:Klebsiella pneumoniae; D008213:Lymphocyte Activation / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D012515:Mast-Cell Sarcoma / Q000276:immunology; D051379:Mice; D008809:Mice, Inbred C3H; D008811:Mice, Inbred DBA; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D001426:Bacterial Proteins; D006023:Glycoproteins; D007375:Interleukin-1; D014409:Tumor Necrosis Factor-alpha; C037567:glycoprotein, Klebsiella pneumoniae; D003513:Cycloheximide; D007213:Indomethacin