Secretion of TNF-alpha, IL-8 and nitric oxide by macrophages activated with polyanions, and involvement of interferon-gamma in the regulation of cytokine secretion.
When macrophages derived from rat bone marrow were cultured in the presence of polyanions such as acetyl lignin (EP3), sulfonyl lignin (LS) or dextran sulfate (DS), the cells secreted TNF-alpha, IL-8 and nitric oxide (NO). EP3 had a dose-dependent effect on the secretion of TNF-alpha, IL-8 and NO. EP3 significantly affected secretion at concentrations greater than 5 microg/ml. The EP3 effect was at its maximum between concentrations of 50 and 100 microg/ml. LS and DS induced a slight increase in the secretion of cytokines and NO at a concentration of 100 microg/ml. The use of the reverse-transcription polymerase chain reaction (RT-PCR) showed that the increases in cytokine and NO secretion were due to an increase in cytokine mRNAs or NO synthase mRNA. Anti-TNF-alpha antibodies partially inhibited NO secretion by EP3-activated macrophages, although IL-8 secretion was independent of antibody treatment. The secretion of TNF-alpha and NO was also unaffected by the addition of anti-IL-8 antibodies. The addition of interferon-gamma (IFN-gamma) to the culture medium did not alter TNF-alpha and NO secretion by the EP3-activated macrophages, however, IL-8 secretion was increased when a low concentration of IFN-gamma (0.2 U/ml) was added, but was reduced in the presence of a high concentration of IFN-gamma (2000 U/ml). IFN-gamma produced similar effects on cytokine and NO secretion in macrophages activated with lipopolysaccharide (LPS). Therefore, it is concluded that macrophages treated with polyanions secrete cytokines and NO, and that INF-gamma is involved in the regulatory mechanism of cytokine and NO secretion.
Sorimachi
K
K
Department of Microbiology, Dokkyo University School of Medicine, Mibu, Tochigi, 321-0293, Japan.
Akimoto
K
K
Hattori
Y
Y
Ieiri
T
T
Niwa
A
A
D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D001854:Bone Marrow Cells / Q000166:cytology; D002478:Cells, Cultured; D016264:Dextran Sulfate / Q000494:pharmacology; D006706:Homeostasis; D007371:Interferon-gamma / Q000502:physiology*; D007375:Interleukin-1 / Q000276:immunology; D016209:Interleukin-8 / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D008031:Lignin / Q000031:analogs & derivatives / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008262:Macrophage Activation / Q000276:immunology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D009569:Nitric Oxide / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics* / Q000276:immunology / Q000378:metabolism
D000906:Antibodies; D007375:Interleukin-1; D016209:Interleukin-8; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D007371:Interferon-gamma; D008031:Lignin; D016264:Dextran Sulfate