ETHNOPHARMACOLOGICAL RELEVANCE: In Asia, Qi-Wei-Du-Qi-Wan (QWDQW) is a 
traditional Chinese medicine that has been used to treat chest tightness, cough, 
shortness of breath, night sweats, frequent urination and asthma. QWDQW is 
recorded in Yi Zong Yi Ren Pian (Medical Physician's Compilation), which was 
written by Yang Cheng Liu during the Qing Dynasty.
AIM OF THE STUDY: The traditional Chinese medicine QWDQW is composed of 7 
ingredients and has been used in the treatment of asthma in Asia for hundreds of 
years. However, the mechanism through which QWDQW affects the immune system in 
the treatment of asthma is not known. Therefore, this study aimed to investigate 
whether QWDQW alleviates asthmatic symptoms in mice with chronic asthma induced 
by repeated stimulation with Dermatophagoides pteronyssinus (Der p) and to 
explore the underlying immune modulatory mechanism.
MATERIALS AND METHODS: BALB/c mice were stimulated intratracheally (i.t.) with 
Der p (40 μl, 2.5 μg/μl) once weekly for 6 weeks. Thirty minutes prior to Der p 
stimulation, the mice were treated with QWDQW (0.5 g/kg and 0.17 g/kg) orally. 
Three days after the last stimulation, the mice were sacrificed, and 
infiltration of inflammatory cells, lung histological characteristics, gene 
expression of lung and serum total IgE were assessed. In other experiments, 
RBL-2H3 cells were stimulated with DNP-IgE/DNP-BSA and then treated with QWDQW, 
quercetin, β-carotene, luteolin or a mixture of the three chemicals (Mix13) for 
30 min, and the effects of the drugs on RBL-2H3 cell degranulation after DNP 
stimulation were determined.
RESULTS: QWDQW significantly reduced Der p-induced airway hyperreactivity (AHR) 
and decreased total serum IgE and Der p-specific IgE levels. Histopathological 
examination showed that QWDQW reduced inflammatory cell infiltration and sputum 
secretion from goblet cells in the lungs. Gene expression analysis indicated 
that QWDQW reduced overproduction of IL-12、IFN-γ、IL-13、IL-4、RNATES、Eotaxin and 
MCP-1in lung. Additionally, QWDQW and Mix13 suppressed DNP induced RBL-2H3 
degranulation, and the effect was maximal when quercetin, β-carotene and 
luteolin were administered together.
CONCLUSION: These results indicate that QWDQW plays a role in suppressing 
excessive airway reaction and in specific immune modulation in a mouse model of 
chronic asthma and that QWDQW suppresses mast cell degranulation at defined 
doses of quercetin, β-carotene and luteolin.