Semi-quantitative analysis of cytokine mRNA expression induced by the herbal medicine Sho-saiko-to (TJ-9) using a Gel Doc system

The RT-PCR method was employed to determine the cytokine mRNA expression of human peripheral lymphocytes induced by the Japanese herbal medicine Sho-s aiko-to (TJ-9). The results showed that the mRNA expression of IL-12, IL-1 beta, IL-10, TNF-alpha, G-CSF, and IFN-gamma increased after 6 hr in cultur e. This is the first reported finding that TJ-9 is an IFN-gamma inducer. Ne xt, cytokine mRNA expression was semi-quantitatively measured using the Gel Doc system with a CCD camera and then statistically analyzed in order to d etermine which component of TJ-9 was the true cytokine inducer. The results showed that the scutellaria root is the main component inducing the cytoki nes, while the glycyrrhiza root is the secondary component. When the cytoki ne concentrations in the supernatants of cell cultures were measured by ELI SA, the levels of IL-12, IL-1 beta, IL-10, TNF-alpha, and G-CSF reflected m RNA expression levels in the cell fraction. However, the level of IFN-gamma was below the detectable limit. The effects of various reagents on many di fferent kinds of cytokine mRNA expression could be analyzed objectively in a short time using the Gel Doc system. Many important findings could be dem onstrated by this simple, easy, sensitive, and cheap method. After the clin ical significance of cytokine analysis is confirmed, this method may become a useful clinical examination tool. (C) 2001 Wiley-Liss. Inc.