Xiaoqinglong decoction reduces dendritic cell differentiation and regulates the Th1/Th2 balance in a mouse model of allergic asthma

Abstract

Abstract Background Xiaoqinglong decoction (XQLD) is a classic Chinese medicinal formula that is widely used to treat allergic asthma. Recently, the use of XQLD to treat allergic asthma has inspired research to determine its mechanism of action. Because dendritic cells (DCs) and the T helper 1 (Th1)/Th2 cytokine balance play important roles in allergic asthma, the present work aimed to assess how these immune system components are affected by XQLD. Methods Thirty-six female BALB/C mice were randomly divided into three groups: an ovalbumin-based allergic asthma model group, a XQLD treatment group, and a control group. Histology was performed with haematoxylin and eosin staining and immunohistochemical staining. Bronchoalveolar lavage fluid and blood were collected from the animals and used to analyze the composition of inflammatory cells and expression levels of the cytokines interleukin (IL)-5 and IL-13. The thymic stromal lymphopoietin (TSLP) protein expression was assessed by western blot analysis, and the Gata3 and Tbx21 mRNA levels were assessed by polymerase chain reaction. Results Compared with the OVA group, the levels of TSLP expression, IL-5, IL-13, and immunoglobulin E in the XQLD group were lower (all P Conclusion These findings suggest that XQLD may ameliorate the course of allergic asthma by regulating the Gata3/Tbx21 balance and inhibiting TSLP expression, changes which are indicative of an altered Th1/Th2 balance. Thus, the clinical effectiveness of XQLD in treating allergic asthma may be due to its regulation of Th1/Th2 balance.