Macrophage-activating factor extracted from mycoplasmas.
Mycoplasmas (M. gallisepticum, chicken mycoplasmas), in concert with interferon gamma (IFN gamma), were effective in activating macrophages (M theta) to be tumoricidal. The M theta-activating capacity of mycoplasmas was maintained after treatment with heat. 0.1 M NaOH, 1 M HCl, or trypsin. M theta-activating factor was extracted from mycoplasmas with chloroform/methanol and water (Mf-B). Mf-B was also effective in activating M theta in the presence of IFN gamma. The threshold dose of Mf-B for M theta of ordinary C3H/He mice and that for those of C3H/HeJ mice, the latter being known to be low responders to bacterial lipopolysaccharide, were actually the same. This seems to indicate that the effectiveness of Mf-B was not attributable to possibly contaminating lipopolysaccharides, and that the pathway of activity of Mf-B is different from that of lipopolysaccharides. Since the M theta-activating principle was only a very small part of Mf-B, we have not yet succeeded in identifying it, but there was no evidence that it was protein, nucleic acid, sugar, or lipid. The cytotoxicity of M theta activated by Mf-B plus IFN gamma was dependent on L-arginine in the culture, suggesting that arginine metabolites are involved in M theta cytotoxicity. Mf-B induced a small amount of tumor necrosis factor in M theta, and this induction was markedly enhanced by IFN gamma.
Takema
M
M
Department of Zoology, Faculty of Science, Kyoto University, Japan.
Oka
S
S
Uno
K
K
Nakamura
S
S
Arita
H
H
Tawara
K
K
Inaba
K
K
Muramatsu
S
S
D000818:Animals; D001120:Arginine / Q000494:pharmacology; D002645:Chickens / Q000382:microbiology; D003602:Cytotoxicity, Immunologic / Q000187:drug effects; D005260:Female; D007371:Interferon-gamma / Q000494:pharmacology; D008262:Macrophage Activation / Q000187:drug effects; D016215:Macrophage-Activating Factors / Q000302:isolation & purification* / Q000494:pharmacology; D051379:Mice; D008809:Mice, Inbred C3H; D008811:Mice, Inbred DBA; D009174:Mycoplasma / Q000276:immunology*; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000378:metabolism
D016215:Macrophage-Activating Factors; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D001120:Arginine