title: The synergistic effect of phytohemagglutinin and interferon-gamma on the expression of tumor necrosis factor-alpha from RAW 264.7 cells.
abstract: 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.
authors.affiliation: Department of Immunology, College of Medicine, Konkuk University, Danwol dong, Chungju 380-701, Republic of Korea.
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Chang
authors.forename: Se Hwan
authors.initials: SH
authors.lastname: Mun
authors.forename: Na Young
authors.initials: NY
authors.lastname: Ko
authors.forename: Jun Ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Myung Ha
authors.initials: MH
authors.lastname: Jun
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Seo
authors.forename: Young Mi
authors.initials: YM
authors.lastname: Kim
authors.forename: Wahn Soo
authors.initials: WS
authors.lastname: Choi
authors.forename: Erk
authors.initials: E
authors.lastname: Her
mesh_terms: 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*
chemical_list: D010835:Phytohemagglutinins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma