Role of dendritic cells in consistency between upper and lower airway inflammatory responses: animal experimental studies

In recent years, studies on the consistency between upper and lower airway inflammation have been receiving more attention; however, the function and mechanism of dendritic cells (DCs) in this context are still not clear. In the present research, we studied the function and mechanism of DCs in the consistency between the upper and lower airway inflammatory responses. CD80, CD86, interferon gamma (IFN-γ), and interleukin 4 (IL-4) expression levels in nasal mucosa and lung tissues in a rat model of allergic rhinitis (AR) and asthma (AS) were detected to analyze the relationship between CD80 and CD86 expression levels and upper and lower airway inflammation and IL-4 and IFN-γ expression. The numbers of CD80, CD86, and IL-4-positive cells in the nasal mucosa and lung tissues in the AR and AS experimental groups were significantly higher; however, the number of IFN-γ-positive cells was significantly lower. CD80 and CD86 expression levels in the nasal mucosa positively correlated with their expression in lung tissues. CD80 and CD86 in the nasal mucosa and lung tissues positively correlated with IL-4 and negatively correlated with IFN-γ. DCs participated in the development of upper and lower airway inflammation. Then, DCs and the upper and lower airway inflammatory responses were consistent. The mechanism underlying of DCs in the consistency between the upper and lower airway inflammatory responses might be associated with its induction of the helper T (Th)2 cytokine-dominant expression, thus breaking the original expression balance between Th1 and Th2 cytokines.