Background: Asthma is the most common disease in children, and its pathogenesis is highly complicated.
Methods: CD4+ cells and CD4+ IL-17+ cells were analysed by flow cytometry, and the ratio of CD4+ cells to the pe-riph¬eral blood mononuclear cells (PBMCs) and CD4+ IL-17+ cells to PMBCs were calculated from the control group, acute group, and moder-ate group. The levels of protein expression of IL-6, IL-17, and IL-21 were detected by ELISA in the plasma and culture supernatants of PBMCs of the three groups. The correlations between IL-7 and IL-6, IL-7 and IL-21 were analysed in culture super-natants of PBMCs of the three groups.
Results: The mean ratio of CD4+ IL-17+ cells/peripheral blood mononuclear cells (PBMCs) was 4.32% in the acute group, which was higher than in the control group and moderate group. The levels of IL-6 and IL-17 were elevated, and the levels of IL-21 were decreased in the acute group. The levels of IL-17 and IL-6 were positive-ly correlated (r = 0.182, p = 0.03), and the levels of IL-17 and IL-21 were nega-tively correlated (r = -0.834, p = 0.02).
Conclusions: The results suggest that the levels of IL-17 and IL-6 are related to the severity of asthma. Furthermore, IL-17 may play a role in the development of childhood asthma.