The synergistic effect of phytohemagglutinin and interferon-gamma on the expression of tumor necrosis factor-alpha from RAW 264.7 cells.
Tumor necrosis factor-alpha (TNF-alpha) is a major cytokine of host immune reaction by foreign agents. Phytohemagglutinin (PHA) is a dynamic contributor to mitogenic stimulation and augmentation of host immune defense. Interferon-gamma (IFN-gamma) induces induction of cytokines in macrophages and lymphocytes. The aim of this study was to examine the synergistic effects of PHA plus low dose IFN-gamma on TNF-alpha mRNA production, cytosolic levels, and secretion in RAW 264.7 cells. The cells were stimulated with PHA or IFN-gamma using various concentrations for various times. The effects of PHA on TNF-alpha expression appeared in dose- and time-dependent manners. The maximum doses of PHA and IFN-gamma to produce them were 300 microg/ml PHA and 10 ng/ml IFN-gamma. The optimum time of PHA for the TNF-alpha mRNA production and release were 6 and 7 h after stimulation, respectively, whereas the time of IFN-gamma on them was achieved at 3 and 8 h. Although the TNF-alpha mRNA production, cytosolic levels, and secretion from the cells were slightly detected under 10 microg/ml PHA and 1 ng/ml IFN-gamma, the combination of PHA (10 microg/ml) and IFN-gamma (1 ng/ml) greatly increased them, indicating the synergistic effect of PHA plus low dose IFN-gamma on TNF-alpha expression.
Chang
Sung Ho
SH
Department of Immunology, College of Medicine, Konkuk University, Danwol dong, Chungju 380-701, Republic of Korea.
Mun
Se Hwan
SH
Ko
Na Young
NY
Lee
Jun Ho
JH
Jun
Myung Ha
MH
Seo
Jin Young
JY
Kim
Young Mi
YM
Choi
Wahn Soo
WS
Her
Erk
E
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D007371:Interferon-gamma / Q000378:metabolism / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000378:metabolism; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D018613:Microscopy, Confocal; D010835:Phytohemagglutinins / Q000378:metabolism / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D013601:T-Lymphocytes / Q000378:metabolism; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism*
D010835:Phytohemagglutinins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma