In vitro effects of Saiboku-to on cytokine production from peripheral blood mononuclear cells of bronchial asthma patients

Objective: This study aimed to evaluate the efficacy of Saiboku-to, a Japanese traditional herbal medicine (Kampo), on the production of interleukin-3 (IL-3), interleukin-4 (IL-4), interleukin-5 (IL-5), interferon-gamma (IFN-gamma) and interleukin-2 (IL-2) by peripheral blood mononuclear cells in bronchial asthma patients following antigenic stimulus by the house dust mite. Design: Twelve bronchial asthma patients with IgE RAST (radio-allergosorbent test) scores to mites of 3 and over were enrolled in the study. Separated mononuclear cells from the patients' blood were suspended in a 24-hole plate with 10% fetal calf serum (FCS) and RPMI-1640 medium. Mite antigen was added to the above cell-suspension (final concentration 10 mg/ml) and cultured for 72 hours at 37 degrees C in 5% CO2. Saiboku-to (TJ-96, Tsumura & Co.) was added to the above sample system at the same time as mite antigen and cultured for 72 hours under the same conditions. After 72 hours of incubation, the amount of various cytokines (IL-2, IL-3, IL-4, IL-5, INF-gamma) was measured using enzyme-linked immunoabsorbent assay kits. Results: Saiboku-to 500 mg/L significantly inhibited the production of IL-3 and IL-4 from peripheral blood mononuclear cells. Moreover, it significantly increased the production of INF-gamma from peripheral blood mononuclear cells. Conclusion: These preliminary findings suggest that Saiboku-to could be considered as one of a new class of anti-asthmatic drugs because of its influence on cytokine production.